Science.gov

Sample records for 30th space wing

  1. The 30th AAS Goddard Memorial Symposium. World space programs and fiscal reality: Synopsis

    NASA Astrophysics Data System (ADS)

    A full proceedings of the symposium will be issued later in the year. This synopsis consists of summations of three sessions by appointed rapporteurs. International figures in space and in politics spoke at the sessions. Themes of international cooperation and fiscal reality pervaded the conference. International speakers from Canada, the European Space Agency, Russia, Japan and China and other countries addressed the topic of the symposium. American representation included Senator Barbara Mikulski, former NASA administrator James Beggs and other speakers.

  2. The 30th AAS Goddard Memorial Symposium. World space programs and fiscal reality: Synopsis

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A full proceedings of the symposium will be issued later in the year. This synopsis consists of summations of three sessions by appointed rapporteurs. International figures in space and in politics spoke at the sessions. Themes of international cooperation and fiscal reality pervaded the conference. International speakers from Canada, the European Space Agency, Russia, Japan and China and other countries addressed the topic of the symposium. American representation included Senator Barbara Mikulski, former NASA administrator James Beggs and other speakers.

  3. 30th Arniversary Press Conference

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Marking the occasion of the Apollo 11 30th Anniversary, members of the Apollo and Saturn astronaut programs attended festivities at Marshall Space Flight Center in Huntsville, AL. A press conference was held at the U. S. Space and Rocket Center for the visiting astronauts. Pictured are (L/R): Edgar Mitchell, Walt Cunningham, Charlie Duke, Buzz Aldrin, Dick Gordon and Owen Garriott.

  4. 30th Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Bradley, Obie H., Jr. (Compiler); Rogers, John F. (Compiler)

    1996-01-01

    The proceedings of the 30th Aerospace Mechanisms Symposium are reported. NASA Langley Research Center hosted the proceedings held at the Radisson Hotel in Hampton, Virginia on May 15-17, 1996, and Lockheed Martin Missiles and Space Company, Inc. co-sponsored the symposium. Technological areas covered include bearings and tribology; pointing, solar array, and deployment mechanisms; orbiter/space station; and other mechanisms for spacecraft.

  5. Thermal Stresses In Space-Shuttle Wing

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Jenkins, Jerald M.

    1989-01-01

    Combined thermal deformations of wing-skin panel and TPS would not tear SIP layer. Report presents analysis of thermal stresses induced in skin panel, thermal-protection system (TPS), and strain-isolation pad (SIP) of Space Shuttle orbiter. Purpose of analysis to determine whether any part of above mentioned structures overstressed and overdeformed under reentry heating, assuming one TPS tile lost at end of reentry heating.

  6. 30th Apollo Lunar Landing Celebration

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The evening skies over the U. S. Space and Rocket Center in Huntsville, AL burst into life as members of the Huntsville community gathered to celebrate the 30th arniversary of the Lunar Landing. Commerating this historical achievement for NASA and the US Space Program, a replica of the original Saturn V rocket was built on the grounds of the U. S. Space and Rocket Center in Huntsville, AL. On the evening of the anniversary thousands of onlookers cheered as fireworks lit up the night sky behind the massive Saturn V rocket.

  7. Dynamic characteristics of a space-station solar wing array

    SciTech Connect

    Dorsey, J.T.; Bush, H.G.

    1984-06-01

    Describes a solar-wing-array concept which meets space-station requirements for minimum fundamental frequency, component modularity, and growth potential. The basic wing-array design parameters are varied, and the resulting effects on the array vibration frequencies and mode shapes are assessed. The transient response of a free-free space station (incorporating a solar-wing-array point design) to a load applied at the space-station center is studied. The use of the transient response studies in identifying critically loaded structural members is briefly discussed.

  8. Interior view of space in north wing, showing main entry; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of space in north wing, showing main entry; camera facing east. - Mare Island Naval Shipyard, Smithery, California Avenue, west side at California Avenue & Eighth Street, Vallejo, Solano County, CA

  9. Vallejo family sleeping space, west wing, upper floor, looking north ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Vallejo family sleeping space, west wing, upper floor, looking north from the south end. The doorway at far right connects with the dining area. - Vallejo Adobe, Adobe Road at Casa Grande, Petaluma, Sonoma County, CA

  10. Space-time computational analysis of MAV flapping-wing aerodynamics with wing clapping

    NASA Astrophysics Data System (ADS)

    Takizawa, Kenji; Tezduyar, Tayfun E.; Buscher, Austin

    2015-06-01

    Computational analysis of flapping-wing aerodynamics with wing clapping was one of the classes of computations targeted in introducing the space-time (ST) interface-tracking method with topology change (ST-TC). The ST-TC method is a new version of the deforming-spatial-domain/stabilized ST (DSD/SST) method, enhanced with a master-slave system that maintains the connectivity of the "parent" fluid mechanics mesh when there is contact between the moving interfaces. With that enhancement and because of its ST nature, the ST-TC method can deal with an actual contact between solid surfaces in flow problems with moving interfaces. It accomplishes that while still possessing the desirable features of interface-tracking (moving-mesh) methods, such as better resolution of the boundary layers. Earlier versions of the DSD/SST method, with effective mesh update, were already able to handle moving-interface problems when the solid surfaces are in near contact or create near TC. Flapping-wing aerodynamics of an actual locust, with the forewings and hindwings crossing each other very close and creating near TC, is an example of successfully computed problems. Flapping-wing aerodynamics of a micro aerial vehicle (MAV) with the wings of an actual locust is another example. Here we show how the ST-TC method enables 3D computational analysis of flapping-wing aerodynamics of an MAV with wing clapping. In the analysis, the wings are brought into an actual contact when they clap. We present results for a model dragonfly MAV.

  11. The effect of phase angle and wing spacing on tandem flapping wings

    NASA Astrophysics Data System (ADS)

    Broering, Timothy M.; Lian, Yong-Sheng

    2012-12-01

    In a tandem wing configuration, the hindwing often operates in the wake of the forewing and, hence, its performance is affected by the vortices shed by the forewing. Changes in the phase angle between the flapping motions of the fore and the hind wings, as well as the spacing between them, can affect the resulting vortex/wing and vortex/vortex interactions. This study uses 2D numerical simulations to investigate how these changes affect the leading dege vortexes (LEV) generated by the hindwing and the resulting effect on the lift and thrust coefficients as well as the efficiencies. The tandem wing configuration was simulated using an incompressible Navier-Stokes solver at a chord-based Reynolds number of 5 000. A harmonic single frequency sinusoidal oscillation consisting of a combined pitch and plunge motion was used for the flapping wing kinematics at a Strouhal number of 0.3. Four different spacings ranging from 0.1 chords to 1 chord were tested at three different phase angles, 0°, 90° and 180°. It was found that changes in the spacing and phase angle affected the timing of the interaction between the vortex shed from the forewing and the hindwing. Such an interaction affects the LEV formation on the hindwing and results in changes in aerodynamic force production and efficiencies of the hindwing. It is also observed that changing the phase angle has a similar effect as changing the spacing. The results further show that at different spacings the peak force generation occurs at different phase angles, as do the peak efficiencies.

  12. Thermal response of Space Shuttle wing during reentry heating

    NASA Technical Reports Server (NTRS)

    Gong, L.; Ko, W. L.; Quinn, R. D.

    1984-01-01

    A structural performance and resizing (SPAR) finite element thermal analysis computer program was used in the heat transfer analysis of the space shuttle orbiter that was subjected to reentry aerodynamic heatings. One wing segment of the right wing (WS 240) and the whole left wing were selected for the thermal analysis. Results showed that the predicted thermal protection system (TPS) temperatures were in good agreement with the space transportation system, trajectory 5 (STS-5) flight-measured temperatures. In addition, calculated aluminum structural temperatures were in fairly good agreement with the flight data up to the point of touchdown. Results also showed that the internal free convection had a considerable effect on the change of structural temperatures after touchdown.

  13. Thermal response of Space Shuttle wing during reentry heating

    NASA Technical Reports Server (NTRS)

    Gong, L.; Ko, W. L.; Quinn, R. D.

    1984-01-01

    A structural performance and resizing (SPAR) finite element thermal analysis computer program was used in the heat transfer analysis of the Space Shuttle Orbiter that was subjected to reentry aerodynamic heatings. One wing segment of the right wing (WS 240) and the whole left wing were selected for the thermal analysis. Results showed that the predicted thermal protection system (TPS) temperatures were in good agreement with the space transportation system, trajectory 5 (STS-5) flight-measured temperatures. In addition, calculated aluminum structural temperatures were in fairly good agreement with flight data up to the point of touchdown. Results also showed that the internal free convection has a considerable effect on the change of structural temperatures after touchdown.

  14. Computer-aided space shuttle orbiter wing design study

    NASA Technical Reports Server (NTRS)

    Phillips, W. P.; Decker, J. P.; Rau, T. R.; Glatt, C. R.

    1974-01-01

    An analytical and experimental investigation has been made to provide a space shuttle orbiter wing design that met the guideline requirements of landing performance, stability, and hypersonic trim for a specified center-of-gravity envelope. The analytical study was facilitated by the use of the Optimal Design Integration system (ODIN) and the experimental part of the investigation was conducted in the Langley low-turbulence pressure tunnel and the Langley continuous-flow hypersonic tunnel.

  15. Atmospheric reentry flight test of winged space vehicle

    NASA Astrophysics Data System (ADS)

    Inatani, Yoshifumi; Akiba, Ryojiro; Hinada, Motoki; Nagatomo, Makoto

    A summary of the atmospheric reentry flight experiment of winged space vehicle is presented. The test was conducted and carried out by the Institute of Space and Astronautical Science (ISAS) in Feb. 1992 in Kagoshima Space Center. It is the first Japanese atmospheric reentry flight of the controlled lifting vehicle. A prime objective of the flight is to demonstrate a high speed atmospheric entry flight capability and high-angle-of-attack flight capability in terms of aerodynamics, flight dynamics and flight control of these kind of vehicles. The launch of the winged vehicle was made by balloon and solid propellant rocket booster which was also the first trial in Japan. The vehicle accomplishes the lfight from space-equivalent condition to the atmospheric flight condition where reaction control system (RCS) attitude stabilization and aerodynamic control was used, respectively. In the flight, the vehicle's attitude was measured by both an inertial measurement unit (IMU) and an air data sensor (ADS) which were employed into an auto-pilot flight control loop. After completion of the entry transient flight, the vehicle experienced unexpected instability during the atmospheric decelerating flight; however, it recovered the attitude orientation and completed the transonic flight after that. The latest analysis shows that it is due to the ADS measurement error and the flight control gain scheduling; what happened was all understood. Some details of the test and the brief summary of the current status of the post flight analysis are presented.

  16. Rapid State Space Modeling Tool for Rectangular Wing Aeroservoelastic Studies

    NASA Technical Reports Server (NTRS)

    Suh, Peter M.; Conyers, Howard J.; Mavris, Dimitri N.

    2014-01-01

    This paper introduces a modeling and simulation tool for aeroservoelastic analysis of rectangular wings with trailing edge control surfaces. The inputs to the code are planform design parameters such as wing span, aspect ratio and number of control surfaces. A doublet lattice approach is taken to compute generalized forces. A rational function approximation is computed. The output, computed in a few seconds, is a state space aeroservoelastic model which can be used for analysis and control design. The tool is fully parameterized with default information so there is little required interaction with the model developer. Although, all parameters can be easily modified if desired.The focus of this paper is on tool presentation, verification and validation. This process is carried out in stages throughout the paper. The rational function approximation is verified against computed generalized forces for a plate model. A model composed of finite element plates is compared to a modal analysis from commercial software and an independently conducted experimental ground vibration test analysis. Aeroservoelastic analysis is the ultimate goal of this tool. Therefore the flutter speed and frequency for a clamped plate are computed using V-g and V-f analysis. The computational results are compared to a previously published computational analysis and wind tunnel results for the same structure. Finally a case study of a generic wing model with a single control surface is presented. Verification of the state space model is presented in comparison to V-g and V-f analysis. This also includes the analysis of the model in response to a 1-cos gust.

  17. Rapid State Space Modeling Tool for Rectangular Wing Aeroservoelastic Studies

    NASA Technical Reports Server (NTRS)

    Suh, Peter M.; Conyers, Howard J.; Mavris, Dimitri N.

    2015-01-01

    This paper introduces a modeling and simulation tool for aeroservoelastic analysis of rectangular wings with trailing-edge control surfaces. The inputs to the code are planform design parameters such as wing span, aspect ratio, and number of control surfaces. Using this information, the generalized forces are computed using the doublet-lattice method. Using Roger's approximation, a rational function approximation is computed. The output, computed in a few seconds, is a state space aeroservoelastic model which can be used for analysis and control design. The tool is fully parameterized with default information so there is little required interaction with the model developer. All parameters can be easily modified if desired. The focus of this paper is on tool presentation, verification, and validation. These processes are carried out in stages throughout the paper. The rational function approximation is verified against computed generalized forces for a plate model. A model composed of finite element plates is compared to a modal analysis from commercial software and an independently conducted experimental ground vibration test analysis. Aeroservoelastic analysis is the ultimate goal of this tool, therefore, the flutter speed and frequency for a clamped plate are computed using damping-versus-velocity and frequency-versus-velocity analysis. The computational results are compared to a previously published computational analysis and wind-tunnel results for the same structure. A case study of a generic wing model with a single control surface is presented. Verification of the state space model is presented in comparison to damping-versus-velocity and frequency-versus-velocity analysis, including the analysis of the model in response to a 1-cos gust.

  18. Rapid State Space Modeling Tool for Rectangular Wing Aeroservoelastic Studies

    NASA Technical Reports Server (NTRS)

    Suh, Peter M.; Conyers, Howard Jason; Mavris, Dimitri N.

    2015-01-01

    This report introduces a modeling and simulation tool for aeroservoelastic analysis of rectangular wings with trailing-edge control surfaces. The inputs to the code are planform design parameters such as wing span, aspect ratio, and number of control surfaces. Using this information, the generalized forces are computed using the doublet-lattice method. Using Roger's approximation, a rational function approximation is computed. The output, computed in a few seconds, is a state space aeroservoelastic model which can be used for analysis and control design. The tool is fully parameterized with default information so there is little required interaction with the model developer. All parameters can be easily modified if desired. The focus of this report is on tool presentation, verification, and validation. These processes are carried out in stages throughout the report. The rational function approximation is verified against computed generalized forces for a plate model. A model composed of finite element plates is compared to a modal analysis from commercial software and an independently conducted experimental ground vibration test analysis. Aeroservoelastic analysis is the ultimate goal of this tool, therefore, the flutter speed and frequency for a clamped plate are computed using damping-versus-velocity and frequency-versus-velocity analysis. The computational results are compared to a previously published computational analysis and wind-tunnel results for the same structure. A case study of a generic wing model with a single control surface is presented. Verification of the state space model is presented in comparison to damping-versus-velocity and frequency-versus-velocity analysis, including the analysis of the model in response to a 1-cos gust.

  19. Wind-tunnel roll-damping measurements of a winged space shuttle configuration in launch attitude

    NASA Technical Reports Server (NTRS)

    Hess, R. W.; Davenport, E. E.

    1973-01-01

    Ground-wind load studies were conducted on three model configurations to assess the importance of aeroelastic instabilities of erected space shuttle vehicles. Roll damping was measured on a fuselage-alone model, which had a D cross section, and a fuselage and tail surfaces in combination with either a clipped-delta wing or a low-sweep tapered wing as the primary lifting surface. The largest negative roll-damping coefficients were measured with the fuselage-alone configuration and were a function of wind azimuth. At the wind azimuths at which the wing-fuselage configuration was unstable, the negative roll-damping coefficients were a function of reduced frequency.

  20. 14. Photocopy of photograph (original photograph in possession of 30th ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Photocopy of photograph (original photograph in possession of 30th Audiovisual Squadron, Vandenberg Air Force Base, California). Photography by United States Air Force, date unknown. ATLAS VEHICLE BEING PREPARED FOR LAUNCH FROM SLC-3E. NOTE EXTERNAL SHEATHING AND CUPOLA ON MOBILE SERVICE TOWER. - Vandenberg Air Force Base, Space Launch Complex 3, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  1. 13. Photocopy of photograph (original photograph in possession of 30th ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Photocopy of photograph (original photograph in possession of 30th Audiovisual Squadron, Vandenberg Air Force Base, California). Photography by United States Air Force, date unknown. THRUST AUGMENTED THOR PREPARED FOR LAUNCH FROM SLC-3W. - Vandenberg Air Force Base, Space Launch Complex 3, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  2. 12. Photocopy of photograph (original photograph in possession of 30th ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Photocopy of photograph (original photograph in possession of 30th Audiovisual Squadron, Vandenberg Air Force Base, California). Photography by United States Air Force, date unknown. LAUNCH OF AN ATLAS FROM SLC-3. MOBILE SERVICE TOWER (MST) IN PARKED POSITION. - Vandenberg Air Force Base, Space Launch Complex 3, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  3. Remote sensing from space. Proceedings of Symposium 3, Workshop V andof the COSPAR Interdisciplinary Scientific Commission A (Meeting A2) of the COSPAR Twenty-sixth Plenary Meeting held in Toulouse, France, 30th June - 11th July 1986.

    NASA Astrophysics Data System (ADS)

    Goward, S. N.; Ungar, S. G.; Nithack, J.; Hasler, A. F.

    Contents:Terrestrial patterns and processes: perspectives from space (Symp. 3). Quantitative radar remote sensing of land and oceanic surface features (Workshop V). The use of satellite observations for weather prediction (Mtg A2).

  4. Cold war historic properties of the 21st Space Wing Air Force Space Command

    SciTech Connect

    Hoffecker, J.F.; Whorton, M.; Buechler, C.R.

    1996-03-01

    A Legacy-funded inventory and evaluation of facilities dating to the Cold War era was conducted for the USAF 21{sup ST} Space Wing (AFSPC). The mission of the Wing includes early warning of missile launches and detection and tracking of space objects. The political and military strategic context for these facilities was developed through an overview of Cold War history, subdivided into four major periods: (1) origins of the conflict, (2) confrontation and crisis, (3) sustained superpower balance based on mutual deterrence, and (4) renewed confrontation and collapse of the Soviet Union. The enormous importance of early warning systems in maintaining the balance of power between the USA and the Soviet Union is discussed in more detail as a subset of the general context of the Cold War history to provide additional background for evaluating the 21{sup ST} Space Wing systems. In addition, a history of each installation was prepared and placed in the context of the broader history of the Cold War. For instance, the effort to develop a credible nuclear threat in the early 1950s is represented by the construction of Thule AB as a forward bomber base in 1951. The growing concern with a Soviet ICBM threat in the late 1950s is reflected in the construction of BMEWS at Thule AB and Clear AS during 1958-1961. Development of an antiballistic missile (ABM) system, subsequently abandoned during the 1970s, is represented by the Safeguard System at Cavalier AS. The U.S. response to the Soviet submarine-launched missile capability during the 1970s is embodied in the deployment of phased-array radar systems to cover the ocean flanks of North America at Cape Cod AS (and later at Eldorado AS). The establishment of AFSPC at Peterson AFB in 1982 reflects the increased strategic importance of space in the later phases of the Cold War. A set of recommendations regarding NRHP eligibility and management of Cold War historic properties was developed as part of the inventory.

  5. On the wings of a dream: The Space Shuttle

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Described are the organization and some of the interests and missions of NASA, the Space Transportation System, the Space Shuttle orbiter Enterprise, astronaut training and clothing, being launched into space, living and working in weightlessness, extravehicular activity, and the return from space to Earth. The various aspects of living in space are treated in considerable detail. This includes how the astronauts prepare food, how they eat and drink, how they sleep, exercise, change clothes and handle personal hygiene when in space.

  6. On the Wings of a Dream: The Space Shuttle.

    ERIC Educational Resources Information Center

    Smithsonian Institution, Washington, DC. National Air And Space Museum.

    This booklet describes the development, training, and flight of the space shuttle. Topics are: (1) "National Aeronautics and Space Administration"; (2) "The Space Transportation System"; (3) "The 'Enterprise'"; (4) "The Shuttle Orbiter"; (5) "Solid Rocket Boosters"; (6) "The External Tank"; (7) "Astronaut Training"; (8) "Getting to Space"; (8)…

  7. Analytic State Space Model for an Unsteady Finite-Span Wing

    NASA Astrophysics Data System (ADS)

    Izraelevitz, Jacob; Zhu, Qiang; Triantafyllou, Michael

    2015-11-01

    Real-time control of unsteady flows, such as force control in flapping wings, requires simple wake models that easily translate into robust control designs. We analytically derive a state-space model for the unsteady trailing vortex system behind a finite aspect-ratio flapping wing. Contrary to prior models, the downwash and lift distributions over the span can be arbitrary, including tip effects. The wake vorticity is assumed to be a fully unsteady distribution, with the exception of quasi-steady (no rollup) geometry. Each discretization along the span has one to four states to represent the local unsteady wake-induced downwash, lift, and circulation. The model supports independently time-varying velocity, heave, and twist along the span. We validate this state-space model through comparison with existing analytic solutions for elliptic wings and an unsteady inviscid panel method.

  8. Wings In Orbit: Scientific and Engineering Legacies of the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Hale, N. Wayne (Editor); Lulla, Kamlesh (Editor); Lane, Helen W. (Editor); Chapline, Gail (Editor)

    2010-01-01

    This Space Shuttle book project reviews Wings In Orbit-scientific and engineering legacies of the Space Shuttle. The contents include: 1) Magnificent Flying Machine-A Cathedral to Technology; 2) The Historical Legacy; 3) The Shuttle and its Operations; 4) Engineering Innovations; 5) Major Scientific Discoveries; 6) Social, Cultural, and Educational Legacies; 7) Commercial Aerospace Industries and Spin-offs; and 8) The Shuttle continuum, Role of Human Spaceflight.

  9. Thermal stress analysis of space shuttle orbiter wing skin panel and thermal protection system

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Jenkins, Jerald M.

    1987-01-01

    Preflight thermal stress analysis of the space shuttle orbiter wing skin panel and the thermal protection system (TPS) was performed. The heated skin panel analyzed was rectangular in shape and contained a small square cool region at its center. The wing skin immediately outside the cool region was found to be close to the state of elastic instability in the chordwise direction based on the conservative temperature distribution. The wing skin was found to be quite stable in the spanwise direction. The potential wing skin thermal instability was not severe enough to tear apart the strain isolation pad (SIP) layer. Also, the preflight thermal stress analysis was performed on the TPS tile under the most severe temperature gradient during the simulated reentry heating. The tensile thermal stress induced in the TPS tile was found to be much lower than the tensile strength of the TPS material. The thermal bending of the TPS tile was not severe enough to cause tearing of the SIP layer.

  10. Avian Wings

    NASA Technical Reports Server (NTRS)

    Liu, Tianshu; Kuykendoll, K.; Rhew, R.; Jones, S.

    2004-01-01

    This paper describes the avian wing geometry (Seagull, Merganser, Teal and Owl) extracted from non-contact surface measurements using a three-dimensional laser scanner. The geometric quantities, including the camber line and thickness distribution of airfoil, wing planform, chord distribution, and twist distribution, are given in convenient analytical expressions. Thus, the avian wing surfaces can be generated and the wing kinematics can be simulated. The aerodynamic characteristics of avian airfoils in steady inviscid flows are briefly discussed. The avian wing kinematics is recovered from videos of three level-flying birds (Crane, Seagull and Goose) based on a two-jointed arm model. A flapping seagull wing in the 3D physical space is re-constructed from the extracted wing geometry and kinematics.

  11. Space Based Ornithology: On the Wings of Migration and Biophysics

    NASA Technical Reports Server (NTRS)

    Smith, James A.

    2005-01-01

    The study of bird migration on a global scale is one of the compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties. Space based technology offers new opportunities to shed understanding on the distribution and migration of organisms on the planet and their sensitivity to human disturbances and environmental changes. Migration is an incredibly diverse and complex behavior. A broad outline of space based research must address three fundamental questions: (1) where could birds be, i.e. what is their fundamental niche constrained by their biophysical limits? (2) where do we actually find birds, i.e. what is their realizable niche as modified by local or regional abiotic and biotic factors, and (3) how do they get there (and how do we know?), that is what are their migration patterns and associated mechanisms? Our working hypothesis is that individual organism biophysical models of energy and water balance, driven by satellite measurements of spatio-temporal gradients in climate and habitat, will help us to explain the variability in avian species richness and distribution. Dynamic state variable modeling provides one tool for studying bird migration across multiple scales and can be linked to mechanistic models describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. Further these models provide an ecological forecasting tool for science and application users to address what are the possible consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration.

  12. Knowledge Discovery in Multidisciplinary Design Space for Regional-Jet Wings Using Data Mining

    NASA Astrophysics Data System (ADS)

    Chiba, Kazuhisa; Jeong, Shinkyu; Obayashi, Shigeru

    Data mining is an important facet of solving multi-objective optimization problems. In the present study, two data mining techniques were applied to a large-scale, real-world multidisciplinary design optimization (MDO) problem to provide knowledge regarding the design space. The use of MDO in the aerodynamics, structure, and aeroelasticity of a regional-jet wing was carried out using high-fidelity evaluation models with an adaptive range multi-objective genetic algorithm. As a result, nine non-dominated solutions were generated and used for tradeoff analysis of three objectives. All solutions evaluated during the evolution were analyzed for the influence of design variables using a self-organizing map (SOM) and a functional analysis of variance (ANOVA) to extract key features of the design space. As SOM and ANOVA compensate for respective disadvantages, the design knowledge could be obtained more clearly by combinating them. Although the MDO results showed inverted gull-wings as non-dominated solutions, one of the key features found by data mining was a non-gull wing geometry. When this knowledge was applied to one optimum solution, the resulting design was found to have better performance compared with the original geometry designed in the conventional manner.

  13. Test and Analysis Correlation of Form Impact onto Space Shuttle Wing Leading Edge RCC Panel 8

    NASA Technical Reports Server (NTRS)

    Fasanella, Edwin L.; Lyle, Karen H.; Gabrys, Jonathan; Melis, Matthew; Carney, Kelly

    2004-01-01

    Soon after the Columbia Accident Investigation Board (CAIB) began their study of the space shuttle Columbia accident, "physics-based" analyses using LS-DYNA were applied to characterize the expected damage to the Reinforced Carbon-Carbon (RCC) leading edge from high-speed foam impacts. Forensic evidence quickly led CAIB investigators to concentrate on the left wing leading edge RCC panels. This paper will concentrate on the test of the left-wing RCC panel 8 conducted at Southwest Research Institute (SwRI) and the correlation with an LS-DYNA analysis. The successful correlation of the LS-DYNA model has resulted in the use of LS-DYNA as a predictive tool for characterizing the threshold of damage for impacts of various debris such as foam, ice, and ablators onto the RCC leading edge for shuttle return-to-flight.

  14. The Hammer Award is presented to KSC and 45th Space Wing.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    At a special presentation in the IMAX 2 Theater in the Kennedy Space Center Visitor Complex, the Hammer Award is presented to Kennedy Space Center and the 45th Space Wing. Among the attendees in the audience are (center) Center Director Roy D. Bridges Jr., flanked by (at left) Commander of the 45th Space Wing Brig. Gen. F. Randall Starbuck and (at right) Commander of the Air Force Space Command General Richard B. Myers. Standing second from right is NASA Administrator Daniel S. Goldin. At the far right is Morley Winograd, director of the National Partnership for Reinventing Government, who presented the award. The Hammer Award is Vice President Al Gore's special recognition of teams of federal employees who have made significant contributions in support of the principles of the National Partnership for Reinventing Government. This Hammer Award acknowledges the accomplishments of a joint NASA and Air Force team that established the Joint Base Operations and Support Contract (J- BOSC) Source Evaluation Board (SEB). Ed Gormel and Chris Fairey, co-chairs of the SEB, accepted the awards for the SEB. The team developed and implemented the acquisition strategy for establishing a single set of base operations and support service requirements for KSC, Cape Canaveral Air Station and Patrick Air Force Base.

  15. High manoeuvring costs force narrow-winged molossid bats to forage in open space.

    PubMed

    Voigt, Christian C; Holderied, Marc W

    2012-04-01

    Molossid bats are specialised aerial-hawkers that, like their diurnal ecological counterparts, swallows and swifts, hunt for insects in open spaces. The long and narrow wings of molossids are considered energetically adapted to fast flight between resource patches, but less suited for manoeuvring in more confined spaces, such as between tree-tops or in forest gaps. To understand whether a potential increase in metabolic costs of manoeuvring excludes molossids from foraging in more confined spaces, we measured energy costs and speed of manoeuvring flight in two tropical molossids, 18 g Molossus currentium and 23 g Molossus sinaloae, when flying in a ~500 m(3) hexagonal enclosure (~120 m(2) area), which is of similar dimensions as typical forest gaps. Flight metabolism averaged 10.21 ± 3.00 and 11.32 ± 3.54 ml CO(2) min(-1), and flight speeds 5.65 ± 0.47 and 6.27 ± 0.68 m s(-1) for M. currentium and M. sinaloae respectively. Metabolic rate during flight was higher for the M. currentium than for the similar-sized, but broader-winged frugivore Carollia sowelli, corroborating that broad-winged bats are better adapted to flying in confined spaces. These higher metabolic costs of manoeuvring flight may be caused by having to fly slower than the optimal foraging speed, and by the additional metabolic costs for centripetal acceleration in curves. This may preclude molossids from foraging efficiently between canopy trees or in forest gaps. The surprisingly brief burst of foraging activity at dusk of many molossids might be related to the cooling of the air column after sunset, which drives airborne insects to lower strata. Accordingly, foraging activity of molossids may quickly turn unprofitable when the abundance of insects decreases above the canopy. PMID:22048527

  16. Initial rotation-loading and low speed flutter test results for a straight wing version of the space shuttle vehicle

    NASA Technical Reports Server (NTRS)

    Warner, R. W.; Wilcox, P. R.; Gambucci, B. J.

    1972-01-01

    For three straight semispan model space shuttle wings, the maximum total load during rapid rotation from 66 deg to 0 deg angle of attack, at Mach numbers from 0.28 to 0.60, was essentially no higher than that measured for buffet. During slow rotation over the same angle range, there was no visible flutter. For one of the wings, however, unstable aerodynamic damping was established at two fixed angles of attack.

  17. Wings in Orbit: Scientific and Engineering Legacies of the Space Shuttle, 1971-2010

    NASA Technical Reports Server (NTRS)

    Hale, Wayne (Editor); Lane, Helen (Editor); Chapline, Gail (Editor); Lulla, Kamlesh (Editor)

    2011-01-01

    The Space Shuttle is an engineering marvel perhaps only exceeded by the station itself. The shuttle was based on the technology of the 1960s and early 1970s. It had to overcome significant challenges to make it reusable. Perhaps the greatest challenges were the main engines and the Thermal Protection System. The program has seen terrible tragedy in its 3 decades of operation, yet it has also seen marvelous success. One of the most notable successes is the Hubble Space Telescope, a program that would have been a failure without the shuttle's capability to rendezvous, capture, repair, as well as upgrade. Now Hubble is a shining example of success admired by people around the world. As the program comes to a close, it is important to capture the legacy of the shuttle for future generations. That is what "Wings In Orbit" does for space fans, students, engineers, and scientists. This book, written by the men and women who made the program possible, will serve as an excellent reference for building future space vehicles. We are proud to have played a small part in making it happen. Our journey to document the scientific and engineering accomplishments of this magnificent winged vehicle began with an audacious proposal: to capture the passion of those who devoted their energies to its success while answering the question "What are the most significant accomplishments?" of the longestoperating human spaceflight program in our nation s history. This is intended to be an honest, accurate, and easily understandable account of the research and innovation accomplished during the era.

  18. Space shuttle: Static stability and control investigation of NR/GD delta wing booster (B-20) and delta wing orbiter (134-D), volume 3

    NASA Technical Reports Server (NTRS)

    Allen, E. C., Jr.; Eder, F. W.

    1972-01-01

    Experimental aerodynamic investigations have been made on a .0035 scale model North American Rockwell/General Dynamics version of the space shuttle in the NASA/MSFC 14 x 14 Inch Trisonic Wind Tunnel. Static stability and control data were obtained on the delta wing booster alone (B-20) and with the delta wing orbiter (134D) mounted in various positions on the booster. Six component aerodynamic force and moment data were recorded over an angle of attack range from -10 to 24 deg at 0 and 6 deg sideslip angles and from -10 to +10 deg sideslip at 0 deg angle of attack. Mach number ranged from 0.6 to 4.96.

  19. Space Shuttle Orbiter Wing-Leading-Edge Panel Thermo-Mechanical Analysis for Entry Conditions

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.; Song, Kyongchan; Raju, Ivatury S.

    2010-01-01

    Linear elastic, thermo-mechanical stress analyses of the Space Shuttle Orbiter wing-leading-edge panels is presented for entry heating conditions. The wing-leading-edge panels are made from reinforced carbon-carbon and serve as a part of the overall thermal protection system. Three-dimensional finite element models are described for three configurations: integrated configuration, an independent single-panel configuration, and a local lower-apex joggle segment. Entry temperature conditions are imposed and the through-the-thickness response is examined. From the integrated model, it was concluded that individual panels can be analyzed independently since minimal interaction between adjacent components occurred. From the independent single-panel model, it was concluded that increased through-the-thickness stress levels developed all along the chord of a panel s slip-side joggle region, and hence isolated local joggle sections will exhibit the same trend. From the local joggle models, it was concluded that two-dimensional plane-strain models can be used to study the influence of subsurface defects along the slip-side joggle region of these panels.

  20. Atomic Oxygen Exposure of Polyimide Foam for International Space Station Solar Array Wing Blanket Box

    NASA Technical Reports Server (NTRS)

    Finckenor, M. M.; Albyn, K. C.; Watts, E. W.

    2006-01-01

    Onorbit photos of the International Space Station (ISS) solar array blanket box foam pad assembly indicate degradation of the Kapton film covering the foam, leading to atomic oxygen (AO) exposure of the foam. The purpose of this test was to determine the magnitude of particulate generation caused by low-Earth orbital environment exposure of the foam and also by compression of the foam during solar array wing retraction. The polyimide foam used in the ISS solar array wing blanket box assembly is susceptible to significant AO erosion. The foam sample in this test lost one-third of its mass after exposure to the equivalent of 22 mo onorbit. Some particulate was generated by exposure to simulated orbital conditions and the simulated solar array retraction (compression test). However, onorbit, these particles would also be eroded by AO. The captured particles were generally <1 mm, and the particles shaken free of the sample had a maximum size of 4 mm. The foam sample maintained integrity after a compression load of 2.5 psi.

  1. 33 CFR 334.540 - Banana River at the Eastern Range, 45th Space Wing, Cape Canaveral Air Force Station, FL...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., 45th Space Wing, Cape Canaveral Air Force Station, FL; restricted area. 334.540 Section 334.540... navigable waters of the United States, as defined at 33 CFR part 329, within the Banana River contiguous to... AND RESTRICTED AREA REGULATIONS § 334.540 Banana River at the Eastern Range, 45th Space Wing,...

  2. Space Shuttle flutter as affected by wing-body aerodynamic interaction

    NASA Technical Reports Server (NTRS)

    Chipman, R. R.; Rauch, F. J.; Shyprykevich, P.; Hess, R. W.

    1974-01-01

    In the NASA Langley Research Center 26-inch transonic blowdown wind-tunnel, flutter speeds were measured on 1/80-th scale semispan models of the orbiter wing, the complete Space Shuttle, and intermediate component combinations. Using the doublet lattice method combined with slender body theory to calculate unsteady aerodynamic forces, subsonic flutter speeds were computed for comparison. Aerodynamic interaction was found by test and analysis to raise the flutter speed in some configurations while lowering it in others. Although at Mach number less than 0.7, predicted speeds correlated to within 6% of those measured, rapid deterioration of the agreement occurred at higher subsonic Mach numbers, especially on the more complicated configurations. Additional analysis showed that aerodynamic forces arising from body flexibility potentially can have a large effect on flutter speed, but that the current shuttle design is not so affected.

  3. Flutter of Winged Reentry Space Vehicles Affected by an Elastic Attachment in Launching Configuration

    NASA Astrophysics Data System (ADS)

    Kanda, Atsushi; Ueda, Tetsuhiko

    This paper reports the flutter investigation of a winged reentry space vehicle having rotational modes in dynamic deflection due to an elastic attachment between a vehicle and a booster rocket. The elastic rotational mode is taken into consideration as an elastic rolling mode or an elastic yawing mode. Flutter experiments have been conducted in a transonic wind tunnel. The doublet-point method (DPM) is used to calculate flutter boundaries for this model. It is shown that an elastic rolling mode may lower the critical speed of anti-symmetric mode flutter because its existence alters the natural vibration mode of anti-symmetric bending which causes flutter. On the other hand, a coupling between an elastic yawing mode and an anti-symmetric bending one becomes critical in the different model.

  4. 33 CFR 334.595 - Atlantic Ocean off Cape Canaveral; 45th Space Wing, Cape Canaveral Air Force Station, FL...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... navigable waters of the United States, as defined at 33 CFR part 329, contiguous to the area offshore of... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Atlantic Ocean off Cape Canaveral... AND RESTRICTED AREA REGULATIONS § 334.595 Atlantic Ocean off Cape Canaveral; 45th Space Wing,...

  5. 33 CFR 334.595 - Atlantic Ocean off Cape Canaveral; 45th Space Wing, Cape Canaveral Air Force Station, FL...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... navigable waters of the United States, as defined at 33 CFR part 329, contiguous to the area offshore of... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Atlantic Ocean off Cape Canaveral... AND RESTRICTED AREA REGULATIONS § 334.595 Atlantic Ocean off Cape Canaveral; 45th Space Wing,...

  6. Formation of Leading-Edge Pinholes in the Space Shuttle Wings Investigated

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.

    2000-01-01

    The space shuttle wing leading edge and nose cap are composed of a carbon/carbon composite that is protected by silicon carbide. The coefficient of thermal expansion mismatch leads to cracks in the silicon carbide. The outer coating of the silicon carbide is a sodium-silicate-based glass that becomes fluid at the shuttles high reentry temperatures and fills these cracks. Small pinholes roughly 0.1 mm in diameter have been observed on these materials after 12 or more flights. These pinholes have been investigated by researchers at the NASA Johnson Space Center, Rockwell International, the Boeing Company, Lockheed Martin Corporation, and the NASA Glenn Research Center at Lewis Field to determine the possible sources and the extent of damage. A typical pinhole is illustrated in the photomicrographs. These pinholes are found primarily on the wing leading edges and not on the nose cap, which is covered when the orbiter is on the launch pad. The pinholes are generally associated with a bead of zincrich glass. Examination of the orbiter and launch structure indicates that weathering paint on the launch structure leads to deposits of zinc-containing paint flakes on the wing leading edge. These may become embedded in the crevices of the wing leading edge and form the observed zinc-rich glass. Laboratory experiments indicate that zinc oxide reacts vigorously with the glass coating on the silicon carbide. Thus, it is likely that this is the reaction that leads to pinhole formation (Christensen, S.V.: Reinforced Carbon/Carbon Pin Hole Formation Through Zinc Oxide Attack. Rockwell International Internal Letter, RDW 96 057, May 1996). Cross-sectional examination of pinholes suggests that they are enlarged thermal expansion mismatch cracks. This is illustrated in the photomicrographs. A careful microstructural analysis indicates that the pinhole walls consist of layers of zinc-containing glass. Thus, pinholes are likely formed by zinc oxide particles lodging in crevices and

  7. Analytical and experimental study of the effects of wing-body aerodynamic interaction on space shuttle subsonic flutter

    NASA Technical Reports Server (NTRS)

    Chipman, R. R.; Rauch, F. J.

    1975-01-01

    The effects on flutter of the aerodynamic interaction between the space shuttle bodies and wing, 1/80th-scale semispan models of the orbiter wing, the complete shuttle and intermediate component combinations were tested in the NASA Langley Research Center 26-inch Transonic Blowdown Wind Tunnel. Using the double lattice method combined with slender body theory to calculate unsteady aerodynamic forces, subsonic flutter speeds were computed for comparison. Using calculated complete vehicle modes, flutter speed trends were computed for the full scale vehicle at an altitude of 15,200 meters and a Mach number of 0.6. Consistent with findings of the model studies, analysis shows the shuttle to have the same flutter speed as an isolated cantilevered wing.

  8. Proceedings of the 30th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting

    NASA Technical Reports Server (NTRS)

    Breakiron, Lee A. (Editor)

    1999-01-01

    This document is a compilation of technical papers presented at the 30th Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting held 1-3 December 1998 at the Hyatt Regency Hotel at Reston Town Center, Reston, Virginia. Papers are in the following categories: 1) Recent developments in rubidium, cesium, and hydrogen-based atomic frequency standards, and in trapped-ion and space clock technology; 2) National and international applications of PTTI technology with emphasis on GPS and GLONASS timing, atomic time scales, and telecommunications; 3) Applications of PTTI technology to evolving military navigation and communication systems; geodesy; aviation; and pulsars; and 4) Dissemination of precise time and frequency by means of GPS, geosynchronous communication satellites, computer networks, WAAS, and LORAN.

  9. The 30th International Symposium on Lattice Field Theory

    NASA Astrophysics Data System (ADS)

    Kamleh, Waseem; Leinweber, Derek; Mahbub, Selim; Matevosyan, Hrayr; Thomas, Anthony; Williams, Anthony; Young, Ross; Zanotti, James

    Lattice 2012, the 30th International Symposium on Lattice Field Theory was held in Cairns, Australia from Sunday the 24th of June to Friday the 29th June 2012. It was held at the Cairns Convention Centre, providing world-class facilities in a beautiful location. Fine weather and easy access to world heritage attractions including the Great Barrier Reef and the Wet Tropics Rainforests made for an extraordinary experience. The conference was organised by the Special Research Centre for the Subatomic Structure of Matter (CSSM) in the School of Chemistry & Physics at the University of Adelaide. More than 285 participants from around the world attended the symposium. The scientific program contained 22 plenary talks and 248 parallel contributions including posters. Most of these are recorded in this proceedings. For 30 years, the Lattice meeting has provided researchers from around the world with an annual forum at which to disseminate and discuss ideas, developments and opportunities in the study of relativistic quantum fields regulated on a spacetime lattice. It fosters the exchange of ideas, networking, and builds relationships between researchers that are essential in facilitating rapid progress and the creation of new knowledge. The program included plenary talks, parallel talks and poster presentations on Algorithms and machines, Applications beyond QCD, Chiral symmetry, Hadron spectroscopy and interactions, Hadron structure, Nonzero temperature and density, Standard model parameters and renormalization, Theoretical developments, Vacuum structure and confinement and Weak decays and matrix elements. The International Advisory Committee provided excellent guidance in planning the scientific program of the conference and we thank the Committee for their important contributions. Thanks also to our presenters for the time and effort they put into preparing their talks and their proceedings. Many thanks to our Conference Secretariat, Sharon Johnson, Silvana Santucci

  10. International Space Station Solar Array Wing On-Orbit Electrical Performance Degradation Measured

    NASA Technical Reports Server (NTRS)

    Gustafson, Eric D.; Kerslake, Thomas W.

    2004-01-01

    The port-side photovoltaic power module (P6) was activated on the International Space Station in December 2000. P6 provides electrical power to channels 2B and 4B to operate ISS power loads. A P6 is shown in the preceding photograph. This article highlights the work done at the NASA Glenn Research Center to calculate the on-orbit degradation of the P6 solar array wings (SAWs) using on-orbit data from December 2000 to February 2003. During early ISS operations, the 82 strings of photovoltaic cells that make up a SAW can provide much more power than is necessary to meet the demand. To deal with excess power, a sequential shunt unit successively shunts the current from the strings. This shunt current was the parameter chosen for the SAW performance degradation study for the following reasons: (1) it is based on a direct shunt current measurement in the sequential shunt unit, (2) the shunt current has a low temperature dependence that reduces the data correction error from using a computationally derived array temperature, and (3) the SSU shunt current is essentially the same as the SAW short-circuit current on a per-string basis.

  11. Sequentially-coupled space-time FSI analysis of bio-inspired flapping-wing aerodynamics of an MAV

    NASA Astrophysics Data System (ADS)

    Takizawa, Kenji; Tezduyar, Tayfun E.; Kostov, Nikolay

    2014-08-01

    We present a sequentially-coupled space-time (ST) computational fluid-structure interaction (FSI) analysis of flapping-wing aerodynamics of a micro aerial vehicle (MAV). The wing motion and deformation data, whether prescribed fully or partially, is from an actual locust, extracted from high-speed, multi-camera video recordings of the locust in a wind tunnel. The core computational FSI technology is based on the Deforming-Spatial-Domain/Stabilized ST (DSD/SST) formulation. This is supplemented with using NURBS basis functions in temporal representation of the wing and mesh motion, and in remeshing. Here we use the version of the DSD/SST formulation derived in conjunction with the variational multiscale (VMS) method, and this version is called "DSD/SST-VMST." The structural mechanics computations are based on the Kirchhoff-Love shell model. The sequential-coupling technique is applicable to some classes of FSI problems, especially those with temporally-periodic behavior. We show that it performs well in FSI computations of the flapping-wing aerodynamics we consider here. In addition to the straight-flight case, we analyze cases where the MAV body has rolling, pitching, or rolling and pitching motion. We study how all these influence the lift and thrust.

  12. The characterization of tandem and corrugated wings

    NASA Astrophysics Data System (ADS)

    Lian, Yongsheng; Broering, Timothy; Hord, Kyle; Prater, Russell

    2014-02-01

    Dragonfly wings have two distinct features: a tandem configuration and wing corrugation. Both features have been extensively studied with the aim to understand the superior flight performance of dragonflies. In this paper we review recent development of tandem and corrugated wing aerodynamics. With regards to the tandem configuration, this review will focus on wing/wing and wing/vortex interactions at different flapping modes and wing spacing. In addition, the aerodynamics of tandem wings under gusty conditions will be reviewed and compared with isolated wings to demonstrate the gust resistance characteristics of flapping wings. Regarding corrugated wings, we review their structural and aerodynamic characteristics.

  13. Introduction to the 30th volume of Inverse Problems

    NASA Astrophysics Data System (ADS)

    Louis, Alfred K.

    2014-01-01

    challenging research domains in condensed form. The diversity of the different topics is especially impressive. The 25th anniversary of Inverse Problems was celebrated with a service to the community, the publication of an issue of topical reviews selected by board members, which presented the achievements and state-of-the-art of the field. The 30th birthday of the journal is now approaching and we found it appropriate to include in the celebration the scientific community that supports the journal by their submissions. A conference, IPTA 2014: Inverse Problems - From Theory to Application (http://ipta2014.iopconfs.org/home), will be held in the home town of our publisher, IOP Publishing, in Bristol on 26-28 August 2014. The conference brings together top researchers, both from academia and industry, and will look at the scientific future of the field. Presentations by keynote speakers, which summarize what the board considers to be new trends, are complemented by contributions submitted by specialists and younger researchers in several minisymposia. To build a bridge to the future generation of researchers, a scientist at the beginning of their career will be giving a lecture. Let me finish with cordial thanks to all of our authors, referees, the members of the Editorial Board and International Advisory Panel, and the publishing team. I wish all of you a successful and healthy New Year and hope to meet many of you in August in Bristol. References [1] Sabatier P C 2012 Rêves et Combats d'un Enseignant-Chercheur, Retour Inverse (Paris: L'Harmattan)

  14. 8. Pennsylvania Railroad: 30th Street Station Powerhouse. Philadelphia, Philadelphia Co., ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Pennsylvania Railroad: 30th Street Station Powerhouse. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 88.11. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

  15. 11. Pennsylvania Railroad: 30th Street Station. Philadelphia, Philadelphia Co., PA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Pennsylvania Railroad: 30th Street Station. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 88.10. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

  16. 10. Pennsylvania Railroad: 30th Street Station. Philadelphia, Philadelphia Co., PA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Pennsylvania Railroad: 30th Street Station. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 88.10. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

  17. 9. Pennsylvania Railroad: 30th Street Station. Philadelphia, Philadelphia Co., PA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Pennsylvania Railroad: 30th Street Station. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 88.10. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

  18. Space shuttle wing leading edge heating environment prediction derived from development flight data

    NASA Technical Reports Server (NTRS)

    Cunningham, J. A.; Haney, J. W., Jr.

    1983-01-01

    An analytical program is in progress at Rockwell International to revise wing leading edge heating predictions in order to improve correlation with STS-1 to -5 flight radiometer data. This paper discusses the methods that have been used to improve agreement between prediction and flight and summarizes the aerodynamic correlations which, when updated, will be used to analyze future orbiter missions.

  19. Proceedings of the 30th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring

    SciTech Connect

    Wetovsky, Marv A; Aguilar-chang, Julio; Arrowsmith, Marie; Arrowsmith, Stephen; Baker, Diane; Begnaud, Michael; Harste, Hans; Maceira, Monica; Patton, Howard; Phillips, Scott; Randall, George; Revelle, Douglas; Rowe, Charlotte; Stead, Richard; Steck, Lee; Whitaker, Rod; Yang, Xiaoning

    2008-09-23

    These proceedings contain papers prepared for the 30th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies, held 23-25 September, 2008 in Portsmouth, Virginia. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Air Force Technical Applications Center (AFTAC), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States’ capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.

  20. 78 FR 62293 - Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay; Oyster Bay, NY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-15

    ... several events associated with the Oyster Bay Oyster Festival. The Oyster Festival 30th Anniversary... CFR Part 165 RIN 1625-AA00 Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay... Festival 30th Anniversary fireworks display. This temporary safety zone is necessary to protect...

  1. Test-Analysis Correlation for Space Shuttle External Tank Foam Impacting RCC Wing Leading Edge Component Panels

    NASA Technical Reports Server (NTRS)

    Lyle, Karen H.

    2008-01-01

    The Space Shuttle Columbia Accident Investigation Board recommended that NASA develop, validate, and maintain a modeling tool capable of predicting the damage threshold for debris impacts on the Space Shuttle Reinforced Carbon-Carbon (RCC) wing leading edge and nosecap assembly. The results presented in this paper are one part of a multi-level approach that supported the development of the predictive tool used to recertify the shuttle for flight following the Columbia Accident. The assessment of predictive capability was largely based on test analysis comparisons for simpler component structures. This paper provides comparisons of finite element simulations with test data for external tank foam debris impacts onto 6-in. square RCC flat panels. Both quantitative displacement and qualitative damage assessment correlations are provided. The comparisons show good agreement and provided the Space Shuttle Program with confidence in the predictive tool.

  2. Inflatable wing

    DOEpatents

    Priddy, Tommy G.

    1988-01-01

    An inflatable wing is formed from a pair of tapered, conical inflatable tubes in bonded tangential contact with each other. The tubes are further connected together by means of top and bottom reinforcement boards having corresponding longitudinal edges lying in the same central diametral plane passing through the associated tube. The reinforcement boards are made of a stiff reinforcement material, such as Kevlar, collapsible in a direction parallel to the spanwise wing axis upon deflation of the tubes. The stiff reinforcement material cooperates with the inflated tubes to impart structural I-beam characteristics to the composite structure for transferring inflation pressure-induced tensile stress from the tubes to the reinforcement boards. A plurality of rigid hoops shaped to provide airfoil definition are spaced from each other along the spanwise axis and are connected to the top and bottom reinforcement boards. Tension lines are employed for stabilizing the hoops along the trailing and leading edges thereof.

  3. Environmental geophysics at Kings Creek Disposal Site and 30th Street Landfill, Aberdeen Proving Ground, Maryland

    SciTech Connect

    Davies, B.E.; Miller, S.F.; McGinnis, L.D.; Daudt, C.R.; Thompson, M.D.; Stefanov, J.E.; Benson, M.A.; Padar, C.A.

    1995-01-01

    Geophysical studies on the Bush River Peninsula in the Edgewood Area of Aberdeen Proving Ground, Maryland, delineate landfill areas and provide diagnostic signatures of the hydrogeologic framework and possible contaminant pathways. These studies indicate that, during the Pleistocene Epoch, alternating stands of high and low seal levels resulted in a complex pattern of shallow channel-fill deposits in the Kings Creek area. Ground-penetrating radar studies reveal a paleochannel greater than 50 ft deep, with a thalweg trending offshore in a southwest direction into Kings Creek. Onshore, the ground-penetrating radar data indicate a 35-ft-deep branch to the main channel, trending to the north-northwest directly beneath the 30th Street Landfill. Other branches are suspected to meet the offshore paleochannel in the wetlands south and east of the 30th Street Landfill. This paleochannel depositional system is environmentally significant because it may control the shallow groundwater flow regime beneath the site. Electromagnetic surveys have delineated the pre-fill lowland area currently occupied by the 30th Street Landfill. Magnetic and conductive anomalies outline surficial and buried debris throughout the study area. On the basis of geophysical data, large-scale dumping has not occurred north of the Kings Creek Disposal Site or east of the 30th Street Landfill.

  4. 33 CFR 334.540 - Banana River at the Eastern Range, 45th Space Wing, Cape Canaveral Air Force Station, FL...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... navigable waters of the United States, as defined at 33 CFR part 329, within the Banana River contiguous to... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Banana River at the Eastern Range... AND RESTRICTED AREA REGULATIONS § 334.540 Banana River at the Eastern Range, 45th Space Wing,...

  5. Effect of configuration modifications on the low-subsonic aerodynamic characteristics of a space shuttle orbiter concept with a blended delta wing-body

    NASA Technical Reports Server (NTRS)

    Freeman, D. C., Jr.

    1972-01-01

    An investigation of several configuration modifications to improve the subsonic stability and performance of a blended delta wing-body space shuttle-orbiter concept has been conducted in the Langley low-turbulence pressure tunnel. These modifications included variations in vertical-tail location and orientation, wing planform shape, and afterbody shape. The model was tested at a Reynolds number, based on body length, of 17 x one million, at a Mack number of 0.25, and at angles of attack from about -4 deg to 22 deg.

  6. JANNAF 30th Propellant Development and Characterization Subcommittee Meeting. Volume I

    NASA Technical Reports Server (NTRS)

    Moore, T. L. (Editor); Becker, D. L. (Editor)

    2002-01-01

    This volume, the first of three volumes, is a compilation of 22 unclassified/unlimited technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 30th Propellant Development & Characterization Subcommittee Meeting, held on 18-21 March 2002 at the Sheraton Colorado Springs Hotel, Colorado Springs, Colorado. The papers presented herein reflect work performed in the areas of green energetic materials (GEM) development; liquid and gel propellant development; propellant surveillance and aging; and propellant chemistry test methods.

  7. Calculation of tapered monoplane wings

    NASA Technical Reports Server (NTRS)

    Amstutz, E

    1930-01-01

    The tapered wing shape increases the lift in the middle of the wing and thus reduces the bending moment of the lifting forces in the plane of symmetry. Since this portion of the wing is the thickest, the stresses of the wing material are reduced and desirable space is provided for stowing the loads in the wing. This statically excellent form of construction, however, has aerodynamic disadvantages which must be carefully weighed, if failures are to be avoided. This treatise is devoted to the consideration of these problems.

  8. Unsteady aerodynamic analysis of space shuttle vehicles. Part 2: Steady and unsteady aerodynamics of sharp-edged delta wings

    NASA Technical Reports Server (NTRS)

    Ericsson, L. E.; Reding, J. P.

    1973-01-01

    An analysis of the steady and unsteady aerodynamics of sharp-edged slender wings has been performed. The results show that slender wing theory can be modified to give the potential flow static and dynamic characteristics in incompressible flow. A semiempirical approximation is developed for the vortex-induced loads, and it is shown that the analytic approximation for sharp-edged slender wings gives good prediction of experimentally determined steady and unsteady aerodynamics at M = 0 and M = 1. The predictions are good not only for delta wings but also for so-called arrow and diamond wings. The results indicate that the effects of delta planform lifting surfaces can be included in a simple manner when determining elastic launch vehicle dynamic characteristics. For Part 1 see (N73-32763).

  9. Off-Nominal Performance of the International Space Station Solar Array Wings Under Orbital Eclipse Lighting Scenarios

    NASA Technical Reports Server (NTRS)

    Kerslake, Thomas W.; Scheiman, David A.

    2005-01-01

    This paper documents testing and analyses to quantify International Space Station (ISS) Solar Array Wing (SAW) string electrical performance under highly off-nominal, low-temperature-low-intensity (LILT) operating conditions with nonsolar light sources. This work is relevant for assessing feasibility and risks associated with a Sequential Shunt Unit (SSU) remove and replace (R&R) Extravehicular Activity (EVA). During eclipse, SAW strings can be energized by moonlight, EVA suit helmet lights or video camera lights. To quantify SAW performance under these off-nominal conditions, solar cell performance testing was performed using full moon, solar simulator and Video Camera Luminaire (VCL) light sources. Test conditions included 25 to 110 C temperatures and 1- to 0.0001-Sun illumination intensities. Electrical performance data and calculated eclipse lighting intensities were combined to predict SAW current-voltage output for comparison with electrical hazard thresholds. Worst case predictions show there is no connector pin molten metal hazard but crew shock hazard limits are exceeded due to VCL illumination. Assessment uncertainties and limitations are discussed along with operational solutions to mitigate SAW electrical hazards from VCL illumination. Results from a preliminary assessment of SAW arcing are also discussed. The authors recommend further analyses once SSU, R&R, and EVA procedures are better defined.

  10. The Hammer Award is presented to KSC and 45th Space Wing.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    KSC's Director of Public Affairs Joe Gordon (left) applauds as Ed Gormel and Chris Fairey are named recipients of the Hammer Award at a special presentation in the IMAX 2 Theater in the Kennedy Space Center Visitor Complex. Presenting the award is Morley Winograd (at the podium), director of the National Partnership for Reinventing Government. The Hammer Award is Vice President Al Gore's special recognition of teams of federal employees who have made significant contributions in support of the principles of the National Partnership for Reinventing Government. This Hammer Award acknowledges the accomplishments of a joint NASA and Air Force team that established the Joint Base Operations and Support Contract (J-BOSC) Source Evaluation Board (SEB). Gormel and Fairey are co-chairs of the SEB. The team developed and implemented the acquisition strategy for establishing a single set of base operations and support service requirements for KSC, Cape Canaveral Air Station and Patrick Air Force Base.

  11. The 30th Anniversary of the First Reported Cases of AIDS | NIH MedlinePlus the Magazine

    MedlinePlus

    ... Javascript on. Feature: 30 Years of AIDS Research The 30th Anniversary of the First Reported Cases of AIDS Past Issues / Summer ... Contents Dr. Jack Whitescarver Dr. Anthony S. Fauci In the 30 years since the first reported cases of ...

  12. Supersonic aerodynamics of delta wings

    NASA Technical Reports Server (NTRS)

    Wood, Richard M.

    1988-01-01

    Through the empirical correlation of experimental data and theoretical analysis, a set of graphs has been developed which summarize the inviscid aerodynamics of delta wings at supersonic speeds. The various graphs which detail the aerodynamic performance of delta wings at both zero-lift and lifting conditions were then employed to define a preliminary wing design approach in which both the low-lift and high-lift design criteria were combined to define a feasible design space.

  13. Proceedings of the X-15 First Flight 30th Anniversary Celebration

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A technical symposium and pilot's panel discussion were held on June 8, 1989, to commemorate the 30th anniversary of the first free flight of the X-15 rocket-powered research aircraft. The symposium featured technical presentations by former key government and industry participants in the advocacy, design, manufacturing, and flight research program activities. The X-15's technical contributions to the X-30 are cited. The panel discussion participants included seven of the eight surviving research pilots who flew the X-15 experimental aircraft to world altitude and speed records which still stand. Pilot's remarks include descriptions of their most memorable X-15 flight experience. The report also includes a historical perspective of the X-15.

  14. Joukowski wings

    NASA Technical Reports Server (NTRS)

    Margoulis, W

    1922-01-01

    To sum up, Professor Joukowski's theory of supporting wings renders it possible to calculate the coefficient of lift in terms of the angle of attack, and Prandtl's coefficient of induced drag and the correction of the angle of attack in terms of the disposition and aspect ratio of the wings.

  15. Scapular Winging

    PubMed Central

    Gooding, Benjamin W. T.; Geoghegan, John M.; Wallace, W. Angus; Manning, Paul A.

    2013-01-01

    This review explores the causes of scapula winging, with overview of the relevant anatomy, proposed aetiology and treatment. Particular focus is given to lesions of the long thoracic nerve, which is reported to be the most common aetiological factor.

  16. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  17. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  18. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  19. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  20. Space shuttle: Pressure investigation of a space shuttle launch configuration consisting of a delta-wing orbiter and a swept-wing booster with canard and tip fans (M equals 0.6 to 1.3). Volume 1, part A: Booster data

    NASA Technical Reports Server (NTRS)

    Rampy, J. M.; Blackwell, K. L.; Gomillion, G. R.

    1973-01-01

    Wind tunnel tests to determine the pressure distribution on a space shuttle launch configuration consisting of a delta wing orbiter and a swept wing booster with canard and tip fins were conducted. Pressure data were obtained for the combined orbiter and booster and for the booster alone at Mach numbers from 0.6 to 1.3, angles of attack from minus 8 degrees to plus 10 degrees, and sideslip angles from minus 6 degrees to plus 6 degrees. Pressure data were also obtained for the booster alone without canard at Mach numbers of 0.9 and 1.1. The pressure taps were distributed primarily over the booster upper surface and the orbiter lower surface.

  1. From wakes to wings: using a multi-fidelity approach to design flapping wings

    NASA Astrophysics Data System (ADS)

    Willis, David J.; Salehipour, Hesam

    2014-06-01

    We present two potential flow based computational tools for the design and analysis of efficient, low Reynolds number flapping wings. Our approach starts with a series of wake-only momentum and energetics analyses. We have used and extended the classical wake-only approach to efficiently perform a large number of computations over the flapping parameter space. The method considers the balance of flight forces in the coupled prediction of wing flapping kinematics and flight energetics. Following the wake-only energetics analysis, a quasi-inverse doublet lattice method (qi-DLM) is applied to determine flapping wing shape including localized wing morphing and deformation. This local wing morphing prescribed so that the wing may achieve the desired, minimum power wake vorticity distribution defined by the wake-only analysis. In this paper we illustrate these methods and perform a preliminary study to assess the impact of wing taper, wing camber and wing twist variations on efficient flapping flight.

  2. Proceedings of the Annual Southern Research Conference in Agricultural Education (30th, Lubbock, Texas, July 21-23, 1981).

    ERIC Educational Resources Information Center

    Cepica, M. J.; And Others

    These proceedings contain 20 presentations and reports made during the 30th Annual Research Conference in Agricultural Education in Lubbock, Texas. The keynote address on importance of research to agricultural education is followed by 16 research papers reporting on analysis of student teacher morale before and after student teaching;…

  3. 30th Annual Report to Congress on the Implementation of the "Individuals with Disabilities Education Act," 2008

    ERIC Educational Resources Information Center

    Office of Special Education and Rehabilitative Services, US Department of Education, 2011

    2011-01-01

    This is the 30th Annual Report to Congress on the Implementation of the Individuals with Disabilities Education Act, 2008. Section 664(d) of the Individuals with Disabilities Education Act (IDEA), as reauthorized in 2004, requires that the Department of Education report annually on the progress made toward the provision of a free appropriate…

  4. A Report on the 30th Annual Conference of the International Association of Scientific and Technological University Libraries (IATUL)

    ERIC Educational Resources Information Center

    Tripathi, Manorama

    2010-01-01

    Purpose: The paper aims to report on the 30th IATUL Annual Conference held in Leuven, Belgium, 1-4 June, 2009. Design/methodology/approach: The paper summarises the major themes of the conference as well as giving some specific details of developments at the Indira Gandhi National Open University in India, which supplement the author's…

  5. Prediction of in-depth gap heating ratios from wing glove model test data. [space shuttle orbiter

    NASA Technical Reports Server (NTRS)

    1977-01-01

    In-depth gap heating ratios were predicted down RSI tile sidewalls based on temperature measurements obtained from the JSC arc-jet Wing Glove model tests in order to develop gap heating ratios which resulted in the best possible fit of test data and to produce a set of engineering verification heating ratios similar in shape to one another which could be used at various body points on the Orbiter during reentry. The Rockwell TPS Multidimensional heat conduction program was used to perform 3-D thermal analyses using a 3.0 in. thick section of a curved RSI tile with 283 nodal points. Correlation with test data shows that the predicted heating ratios were significantly higher down in the gap than the zero pressure values for T/C stacks 39 and 38 on the Wing Glove model. For stack 37 (in a low pressure region), the baseline heating ratio overpredicted the temperature data. This analysis, which showed that the heating ratios were a strong function of the product of pressure and pressure gradient, will be used to compare with recent Gap/Step and Ames Double Wedge test/analysis results in the effort to identify the Orbiter gap response to high delta P flight environment.

  6. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  7. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  8. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  9. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  10. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  11. Studies Conducted of Sodium Carbonate Contaminant Found on the Wing Leading Edge and the Nose Cap of the Space Shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.; Palou, Jaime J.

    2003-01-01

    In early 2001, three of the space shuttle orbiters were found to have a sodium carbonate contaminant on the wing leading edge and nose cap. These parts are made of a reinforced carbon/carbon material protected by silicon carbide (SiC) and a glass coating. The glass coating is known as Type A and is primarily sodium silicate with particles of SiC. NASA Glenn Research Center's Environmental Durability Branch was asked to determine the chemistry of this deposit formation and assess any possible detrimental effects. At low temperatures, the reverse reaction is favorable. Previous studies of the corrosion of glass show that carbon dioxide in the presence of water does form sodium carbonate on sodium silicate glass (ref. 1). It is quite likely that a similar scenario exists for the orbiter wing leading edge. All three orbiters that formed sodium carbonate were exposed to rain. This formation of sodium carbonate was duplicated in the laboratory. The Type A glass, which coats the wing leading edge and nose cap, was made in a freestanding form and exposed to water in two separate experiments. In one set of experiments, the coating was placed in a petri dish filled with water. As the water evaporated, sodium carbonate formed. In another case, water was slowly dripped on the coating and sodium carbonate formed. The sodium carbonate was detected by chemical analysis and, in some cases, xray diffraction showed a hydrated sodium carbonate. The next step was to examine possible detrimental effects of this sodium carbonate. There are three likely scenarios for the sodium carbonate deposit: (1) it may be removed with a simple rinse, (2) it may remain and flow back into the Type A glass after heating during reentry, or (3) it may remain and flow onto unprotected SiC and/or other parts after heating during reentry. The effect of case 1 is to remove the Na2O constituent from the Type A glass, thus decreasing its effectiveness as a sealant. Even so, overall, it is probably the best

  12. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  13. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  14. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  15. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  16. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  17. Subsonic and transonic hinge moment and wing bending/torsion characteristics of .015 scale space shuttle models 49-0 and 67-TS in the Rockwell International trisonic wind tunnel (IA70), volume 1

    NASA Technical Reports Server (NTRS)

    Hughes, M. T.; Mennell, R. C.

    1974-01-01

    Experimental aerodynamic investigations were conducted on an 0.015-scale representation of the integrated space shuttle launch vehicle in the trisonic wind tunnel. The primary test objective was to obtain subsonic and transonic elevon and bodyflap hinge moments and wing bending-torsion moments in the presence of the launch vehicle. Wing pressures were also recorded for the upper and lower right wing surfaces at two spanwise stations. The hinge moment, wing bending/torsion moments and wing pressure data were recorded over an angle-of-attack (alpha) range from -8 deg to +8 deg, and angle-of-sideslip (beta) range from -8 deg to +8 deg and at Mach numbers of 0.90, 1.12, 1.24 and 1.50. Tests were also conducted to determine the effects of the orbiter rear attach cross beam and the forward attach wedge and strut diameter. The orbiter alone was tested at 0.90 and 1.24 Mach number only.

  18. An axisymmetric analog two-layer convective heating procedure with application to the evaluation of Space Shuttle Orbiter wing leading edge and windward surface heating

    NASA Technical Reports Server (NTRS)

    Wang, K. C.

    1994-01-01

    A numerical procedure for predicting the convective heating rate of hypersonic reentry vehicles is described. The procedure, which is based on the axisymmetric analog, consists of obtaining the three-dimensional inviscid flowfield solution; then the surface streamlines and metrics are calculated using the inviscid velocity components on the surface; finally, an axisymmetric boundary layer code or approximate convective heating equations are used to evaluate heating rates. This approach yields heating predictions to general three-dimensional body shapes. The procedure has been applied to the prediction of the wing leading edge heating to the Space Shuttle Orbiter. The numerical results are compared with the results of heat transfer testing (OH66) of an 0.025 scale model of the Space Shuttle Orbiter configuration in the Calspan Hypersonic Shock Tunnel (HST) at Mach 10 and angles of attack of 30 and 40 degrees. Comparisons with STS-5 flight data at Mach 9.15 and angle of attack of 37.4 degrees and STS-2 flight data at Mach 12.86 and angle of attack of 39.7 degrees are also given.

  19. PREFACE: 30th EPS Conference on Controlled Fusion and Plasma Physics

    NASA Astrophysics Data System (ADS)

    Koch, R.; Lebedev, S.

    2003-12-01

    The 30th EPS Conference on Controlled Fusion and Plasma Physics took place in St Petersburg, Russian Federation, on 7th--11th July 2003. It was jointly organized by the Ioffe Physico-Technical Institute, the St Petersburg State Polytechnical University and Technical University Applied Physics Ltd, on behalf of the Plasma Physics Division of the European Physical Society (EPS). The members of the local organizing committee were drawn from these institutions: B Kuteev, Chair, Polytechnical University S Lebedev, Vice-Chair, Ioffe Institute A Lebedev, Scientific Secretary, Ioffe Institute V Bakharev, TUAP Ltd V Grigor'yants, Ioffe Institute V Sergeev, Polytechnical University N Zhubr, Ioffe Institute Over the years, the annual conference of the Plasma Physics Division of the European Physical Society has widened its scope. Contributions to the present conference covered widely diversified fields of plasma physics, ranging from magnetic and inertial fusion to low temperature plasmas. Plasma sizes under investigation ranged from tiny to astronomical. The topics covered during the conference were distributed over the following categories: tokamaks, stellarators, high intensity laser produced plasmas and inertial confinement, alternative magnetic confinement, plasma edge physics, plasma heating and current drive, diagnostics, basic plasma physics, astrophysical and geophysical plasmas and low temperature plasmas. The scientific programme and paper selection were the responsibility of the Programme Committee appointed by the Board of the EPS Plasma Physics Division. The committee was composed of: R Koch, Chairman, ERM/KMS Brussels, Belgium E Ascasibar, CIEMAT Madrid, Spain S Atzeni, Università di Roma, Italy G Bonhomme, LPMI Nancy, France C Chiuderi, Università di Firenze, Italy B Kuteev, St Petersburg State Polytechnical,University, Russian Federation M Mauel, Contact person APS-DPP, Columbia University New York, USA R A Pitts, EPFL/CRPP Lausanne, Switzerland R Salomaa

  20. Veins improve fracture toughness of insect wings.

    PubMed

    Dirks, Jan-Henning; Taylor, David

    2012-01-01

    During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m). However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm). This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species. PMID:22927966

  1. 14 CFR 23.201 - Wings level stall.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wings level stall. 23.201 Section 23.201... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight Stalls § 23.201 Wings level... airplane stalls. (b) The wings level stall characteristics must be demonstrated in flight as...

  2. 14 CFR 25.1403 - Wing icing detection lights.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing icing detection lights. 25.1403... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Lights § 25.1403 Wing icing... ice on the parts of the wings that are critical from the standpoint of ice accumulation....

  3. 14 CFR 23.201 - Wings level stall.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wings level stall. 23.201 Section 23.201... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight Stalls § 23.201 Wings level... airplane stalls. (b) The wings level stall characteristics must be demonstrated in flight as...

  4. 14 CFR 25.1403 - Wing icing detection lights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing icing detection lights. 25.1403... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Lights § 25.1403 Wing icing... ice on the parts of the wings that are critical from the standpoint of ice accumulation....

  5. 14 CFR 23.201 - Wings level stall.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wings level stall. 23.201 Section 23.201... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight Stalls § 23.201 Wings level... airplane stalls. (b) The wings level stall characteristics must be demonstrated in flight as...

  6. The Cell Adhesion Molecules Roughest, Hibris, Kin of Irre and Sticks and Stones Are Required for Long Range Spacing of the Drosophila Wing Disc Sensory Sensilla

    PubMed Central

    Linneweber, Gerit Arne; Winking, Mathis; Fischbach, Karl-Friedrich

    2015-01-01

    Most animal tissues and organ systems are comprised of highly ordered arrays of varying cell types. The development of external sensory organs requires complex cell-cell communication in order to give each cell a specific identity and to ensure a regular distributed pattern of the sensory bristles. This involves both long and short range signaling mediated by either diffusible or cell anchored factors. In a variety of processes the heterophilic Irre Cell Recognition Module, consisting of the Neph-like proteins: Roughest, Kin of irre and of the Nephrin-like proteins: Sticks and Stones, Hibris, plays key roles in the recognition events of different cell types throughout development. In the present study these proteins are apically expressed in the adhesive belt of epithelial cells participating in sense organ development in a partially exclusive and asymmetric manner. Using mutant analysis the GAL4/UAS system, RNAi and gain of function we found an involvement of all four Irre Cell Recognition Module-proteins in the development of a highly structured array of sensory organs in the wing disc. The proteins secure the regular spacing of sensory organs showing partial redundancy and may function in early lateral inhibition events as well as in cell sorting processes. Comparisons with other systems suggest that the Irre Cell Recognition module is a key organizer of highly repetitive structures. PMID:26053791

  7. Sequencing to Station in 12 Months (Targeting Orbital 5 Launch, March 30th)

    NASA Technical Reports Server (NTRS)

    Smith, David J.; Burton, Aaron Steven

    2015-01-01

    The Biomolecule Sequencer is a Commercial Off-The-Shelf device developed by Oxford Nanopore Technologies and implements a method of DNA sequencing unlike any other current sequencers. The device measures changes in electrical current through a nanopore depending on the sequence of the DNA strand that is passing through it. Since the technology is built on nanometer-scale ion pores, the hardware itself is exceptionally small (3 x 1 x 58 inches), lightweight (less than 120 grams with USB cable), and powered only by a USB connection. The sequencing device is permanent, while the flow cells, to which the samples are added, are periodically replaced. The goal of our upcoming technology demonstration on ISS is to provide evidence that DNA sequencing in space is possible, which holds the exciting potential to enable the identification of microorganisms, monitor changes in microbes and humans in response to spaceflight, and possibly aid in the detection of DNA-based life elsewhere in the universe.

  8. View east, showing Northwest Wing (Wing 5) and rear elevations ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View east, showing Northwest Wing (Wing 5) and rear elevations of facade and tis flaking wings (Wings 1 and 2) - Hospital for Sick Children, 1731 Bunker Hill Road, Northeast, Washington, District of Columbia, DC

  9. View east, showing Northwest Wing (Wing 5), west wall of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View east, showing Northwest Wing (Wing 5), west wall of the North Wing (Wing 2) and rear elevations of the facade and its flanking wings (Wings 1 and 2) - Hospital for Sick Children, 1731 Bunker Hill Road, Northeast, Washington, District of Columbia, DC

  10. Theory of wing rock

    NASA Technical Reports Server (NTRS)

    Hsu, C.-H.; Lan, C. E.

    1985-01-01

    Wing rock is one type of lateral-directional instabilities at high angles of attack. To predict wing rock characteristics and to design airplanes to avoid wing rock, parameters affecting wing rock characteristics must be known. A new nonlinear aerodynamic model is developed to investigate the main aerodynamic nonlinearities causing wing rock. In the present theory, the Beecham-Titchener asymptotic method is used to derive expressions for the limit-cycle amplitude and frequency of wing rock from nonlinear flight dynamics equations. The resulting expressions are capable of explaining the existence of wing rock for all types of aircraft. Wing rock is developed by negative or weakly positive roll damping, and sustained by nonlinear aerodynamic roll damping. Good agreement between theoretical and experimental results is obtained.

  11. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  12. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  13. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  14. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  15. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  16. The IceCube Collaboration:contributions to the 30 th International Cosmic Ray Conference (ICRC 2007),

    SciTech Connect

    IceCube Collaboration; Ackermann, M.

    2007-11-02

    This paper bundles 40 contributions by the IceCube collaboration that were submitted to the 30th International Cosmic Ray Conference ICRC 2007. The articles cover studies on cosmic rays and atmospheric neutrinos, searches for non-localized, extraterrestrial {nu}{sub e}, {nu}{sub {mu}} and {nu}{sub {tau}} signals, scans for steady and intermittent neutrino point sources, searches for dark matter candidates, magnetic monopoles and other exotic particles, improvements in analysis techniques, as well as future detector extensions. The IceCube observatory will be finalized in 2011 to form a cubic-kilometer ice-Cherenkov detector at the location of the geographic South Pole. At the present state of construction, IceCube consists of 52 paired IceTop surface tanks and 22 IceCube strings with a total of 1426 Digital Optical Modules deployed at depths up to 2350 m. The observatory also integrates the 19 string AMANDA subdetector, that was completed in 2000 and extends IceCube's reach to lower energies. Before the deployment of IceTop, cosmic air showers were registered with the 30 station SPASE-2 surface array. IceCube's low noise Digital Optical Modules are very reliable, show a uniform response and record waveforms of arriving photons that are resolvable with nanosecond precision over a large dynamic range. Data acquisition, reconstruction and simulation software are running in production mode and the analyses, profiting from the improved data quality and increased overall sensitivity, are well under way.

  17. The 30th anniversary of Campylobacter, Helicobacter, and Related Organisms workshops—what have we learned in three decades?

    PubMed Central

    Gaynor, Erin C.; Szymanski, Christine M.

    2012-01-01

    As we commemorate the 30th anniversary of the Campylobacter, Helicobacter, and Related Organisms (CHRO) workshops with this special Frontiers edition, we look back upon three decades of research and provide some highlights from the 16th International CHRO meeting. Although Theodor Escherich himself provided drawings of campylobacters back in the 1880s, Campylobacter jejuni was not identified until the 1950s. Helicobacter pylori was first described to be the causative agent of stomach ulcers at a CHRO meeting by Barry Marshall and Robin Warren—who later received the Nobel Prize for their findings that bacteria could cause diseases previously believed to be caused by human factors. Now, several genome sequences for campylobacters, helicobacters, and related organisms are available and we have moved into an era examining the intersection between host microbial ecology and pathogen infection. Both pioneers and new investigators in the CHRO research field continue to obtain “unexpected results” demonstrating that campylobacters and helicobacters do not follow classic paradigms of other well-characterized gastrointestinal pathogens and we are learning that there is a plethora of interesting related organisms beyond C. jejuni and H. pylori. This review summarizes recent discoveries in CHRO research and the exciting directions ahead. PMID:22919612

  18. Subsonic and transonic aerodynamic characteristics associated with variations in the geometry of the forward portion of irregular planform wings on a .01875 scale LO-100 Langley concept space shuttle orbiter in the Langley 8 foot TPT (LA7B)

    NASA Technical Reports Server (NTRS)

    Vaughn, J. E.; Poucher, D. E.

    1973-01-01

    The experimental longitudinal-and lateral-directional stability characteristics of a Langley conceptual space shuttle orbiter design were obtained for a series of inboard planform fillets in the NASA/LaRC 8-foot transonic pressure tunnel. Fillet sweep angles up to 78 deg were investigated while holding the spanwise intersection of the fillet and wing constant. The data were obtained at Mach numbers of 0.35 to 1.2 and at Reynolds numbers (depending on Mach number) of 1,000,000 to 3,200,000 per foot. The angle of attack was varied from about -2 deg to 22 deg at sideslip.

  19. Flapping of Insectile Wings

    NASA Astrophysics Data System (ADS)

    Huang, Yangyang; Kanso, Eva

    2015-11-01

    Insects use flight muscles attached at the base of the wings to produce impressive wing flapping frequencies. Yet the effects of muscle stiffness on the performance of insect wings remain unclear. Here, we construct an insectile wing model, consisting of two rigid wings connected at their base by an elastic torsional spring and submerged in an oscillatory flow. The wing system is free to rotate and flap. We first explore the extent to which the flyer can withstand roll perturbations, then study its flapping behavior and performance as a function of spring stiffness. We find an optimal range of spring stiffness that results in large flapping amplitudes, high force generation and good storage of elastic energy. We conclude by conjecturing that insects may select and adjust the muscle spring stiffness to achieve desired movement. These findings may have significant implications on the design principles of wings in micro air-vehicles.

  20. Flutter of pairs of aerodynamically interfering delta wings.

    NASA Technical Reports Server (NTRS)

    Chipman, R. R.; Rauch, F. J.; Hess, R. W.

    1973-01-01

    To examine the effect on flutter of the aerodynamic interference between pairs of closely spaced delta wings, several structurally uncoupled 1/80th-scale models were studied by experiment and analysis. Flutter test boundaries obtained in NASA Langley's 26-in. transonic blowdown wind tunnel were compared with subsonic analytical results generated using the doublet lattice method. Trends for several combinations of vertical and longitudinal wing separation were determined, showing flutter speed significantly affected in the closely spaced configurations. A new flutter mechanism coupling one wing's first bending mode with the other wing's first torsion mode was predicted and observed.

  1. Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (30th, Prague, Czech Republic, July 16-21, 2006). Volume 5

    ERIC Educational Resources Information Center

    Novotna, Jarmila, Ed.; Moraova, Hana, Ed.; Kratka, Magdalena, Ed.; Stehlikova, Nad'a, Ed.

    2006-01-01

    This document contains the fifth volume of the proceedings of the 30th Conference of the International Group for the Psychology of Mathematics Education. Conference presentations are centered around the theme "Mathematics at the Centre." This volume features 59 research reports by presenters with last names beginning between Sac and Zaz: (1)…

  2. Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (30th, Prague, Czech Republic, July 16-21, 2006). Volume 1

    ERIC Educational Resources Information Center

    Novotna, Jarmila, Ed.; Moraova, Hana, Ed.; Kratka, Magdalena, Ed.; Stehlikova, Nad'a, Ed.

    2006-01-01

    This volume of the 30th annual proceedings of the International Group for the Psychology of Mathematics Education conference presents: plenary panel papers; research forum papers; short oral communication papers; and poster presentation papers from the meeting. Information relating to discussion groups and working sessions is also provided.…

  3. Proceedings of the 30th Southern Conservation Agricultural Systems Conference and the 8th Annual Georgia Conservation Production Systems Training Conference, Tifton, Georgia, July 29-31, 2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This 2008 conference to be held at the University of Georgia Tifton Campus Conference Center in Tifton, GA, on 29-31 July 2008, will be a joint effort of the 30th Southern Conservation Agricultural Systems Conference (SCASC) and the 8th Annual Conservation Production Systems Training Conference (CPS...

  4. Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (30th, Prague, Czech Republic, July 16-21, 2006). Volume 2

    ERIC Educational Resources Information Center

    Novotna, Jarmila, Ed.; Moraova, Hana, Ed.; Kratka, Magdalena, Ed.; Stehlikova, Nad'a, Ed.

    2006-01-01

    This document contains the second volume of the proceedings of the 30th Annual Conference of the International Group for the Psychology of Mathematics Education. Conference presentations are centered around the theme "Mathematics at the Centre." This volume features 60 research reports by presenters with last names beginning between Abr and Dri:…

  5. Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (30th, Prague, Czech Republic, July 16-21, 2006). Volume 3

    ERIC Educational Resources Information Center

    Novotna, Jarmila, Ed.; Moraova, Hana, Ed.; Kratka, Magdalena, Ed.; Stehlikova, Nad'a, Ed.

    2006-01-01

    This document contains the third volume of the proceedings of the 30th Conference of the International Group for the Psychology of Mathematics Education. Conference presentations are centered around the theme "Mathematics at the Centre." This volume features 60 research reports by presenters with last names beginning between Ead and Kou: (1)…

  6. Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (30th, Prague, Czech Republic, July 16-21, 2006). Volume 4

    ERIC Educational Resources Information Center

    Novotna, Jarmila, Ed.; Moraova, Hana, Ed.; Kratka, Magdalena, Ed.; Stehlikova, Nad'a, Ed.

    2006-01-01

    This document contains the fourth volume of the proceedings of the 30th Conference of the International Group for the Psychology of Mathematics Education. Conference presentations are centered around the theme "Mathematics at the Centre." This volume features 59 research reports by presenters with last names beginning between Kun and Ros: (1)…

  7. Mathematics: Essential Research, Essential Practice. Volumes 1 and 2. Proceedings of the 30th Annual Conference of the Mathematics Education Research Group of Australasia

    ERIC Educational Resources Information Center

    Watson, Jane, Ed.; Beswick, Kim, Ed.

    2007-01-01

    This is a record of the proceedings of the 30th annual conference of the Mathematics Education Research Group of Australasia (MERGA). The theme of the conference is "Mathematics: Essential research, essential practice." The theme draws attention to the importance of developing and maintaining links between research and practice and ties in with…

  8. Space shuttle: Longitudinal aerodynamic characteristics of low aspect ratio wing configurations in ground effect for a moving and stationary ground surface

    NASA Technical Reports Server (NTRS)

    Romere, P. O.; Chambliss, E. B.

    1972-01-01

    A 0.05-scale model of the NASA-MSC Orbiter 040A Configuration was tested. Test duration was approximately 80 hours during which the model was tested in and out of ground effect with a stationary and moving ground belt. Model height from ground plane surface was varied from one and one-half wing span to landing touchdown while angle of attack varied from -4 to 20 degrees. Eleven effectiveness and alternate configuration geometries were tested to insure complete analysis of low aspect ratio wing aircraft in the presence of ground effect. Test Mach number was approximately 0.067 with a corresponding dynamic pressure value of 6.5 psf.

  9. Slotted Aircraft Wing

    NASA Technical Reports Server (NTRS)

    McLean, James D. (Inventor); Witkowski, David P. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    A swept aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one full-span slot is defined by the wing during at least one transonic condition of the wing. The full-span slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  10. Optimum hovering wing planform.

    PubMed

    Nabawy, Mostafa R A; Crowther, William J

    2016-10-01

    Theoretical analysis is used to identify the optimum wing planform of a flapping/revolving wing in hover. This solution is of interest as a benchmark to which hovering wing geometries driven by broader multidisciplinary evolutionary or engineering constraints can be compared. Furthermore, useful insights into the aerodynamic performance of untwisted hovering wings are delivered. It is shown that profile power is minimised by using an untwisted elliptical planform whereas induced power is minimised by a more highly tapered planform similar to that of a hummingbird. PMID:27329340

  11. Flexible flapping wings with self-organized microwrinkles.

    PubMed

    Tanaka, Hiroto; Okada, Hiroyuki; Shimasue, Yosuke; Liu, Hao

    2015-08-01

    Bio-inspired flapping wings with a wrinkled wing membrane were designed and fabricated. The wings consist of carbon fibre-reinforced plastic frames and a polymer film with microscale wrinkles inspired by bird feathers and the corrugations of insect wings. The flexural and tensile stiffness of the wrinkled film can be controlled by modifying the orientations and waveforms of the wrinkles, thereby expanding the design space of flexible wings for micro flapping-wing aerial robots. A self-organization phenomenon was exploited in the fabrication of the microwrinkles such that microscale wrinkles spanning a broad wing area were spontaneously created. The wavy shape of these self-organized wrinkles was used as a mould, and a Parylene film was deposited onto the mould to form a wrinkled wing film. The effect of the waveforms of the wrinkles on the film stiffness was investigated theoretically, computationally and experimentally. Compared with a flat film, the flexural stiffness was increased by two orders of magnitude, and the tensile stiffness was reduced by two orders of magnitude. To demonstrate the effect of the wrinkles on the actual deformation of the flapping wings and the resulting aerodynamic forces, the fabricated wrinkled wings were tested using a tethered electric flapping mechanism. Chordwise unidirectional wrinkles were found to prevent fluttering near the trailing edge and to produce a greater aerodynamic lift compared with a flat wing or a wing with spanwise wrinkles. Our results suggest that the fine stiffness control of the wing film that can be achieved by tuning the microwrinkles can improve the aerodynamic performance of future flapping-wing aerial robots. PMID:26119657

  12. Sensitivity Analysis of Wing Aeroelastic Responses

    NASA Technical Reports Server (NTRS)

    Issac, Jason Cherian

    1995-01-01

    Design for prevention of aeroelastic instability (that is, the critical speeds leading to aeroelastic instability lie outside the operating range) is an integral part of the wing design process. Availability of the sensitivity derivatives of the various critical speeds with respect to shape parameters of the wing could be very useful to a designer in the initial design phase, when several design changes are made and the shape of the final configuration is not yet frozen. These derivatives are also indispensable for a gradient-based optimization with aeroelastic constraints. In this study, flutter characteristic of a typical section in subsonic compressible flow is examined using a state-space unsteady aerodynamic representation. The sensitivity of the flutter speed of the typical section with respect to its mass and stiffness parameters, namely, mass ratio, static unbalance, radius of gyration, bending frequency, and torsional frequency is calculated analytically. A strip theory formulation is newly developed to represent the unsteady aerodynamic forces on a wing. This is coupled with an equivalent plate structural model and solved as an eigenvalue problem to determine the critical speed of the wing. Flutter analysis of the wing is also carried out using a lifting-surface subsonic kernel function aerodynamic theory (FAST) and an equivalent plate structural model. Finite element modeling of the wing is done using NASTRAN so that wing structures made of spars and ribs and top and bottom wing skins could be analyzed. The free vibration modes of the wing obtained from NASTRAN are input into FAST to compute the flutter speed. An equivalent plate model which incorporates first-order shear deformation theory is then examined so it can be used to model thick wings, where shear deformations are important. The sensitivity of natural frequencies to changes in shape parameters is obtained using ADIFOR. A simple optimization effort is made towards obtaining a minimum weight

  13. Space shuttle: Heat transfer investigation of the McDonnell-Douglas delta wing orbiter at a nominal Mach number of 10.5

    NASA Technical Reports Server (NTRS)

    Eaves, R. H.; Buchanan, T. D.

    1972-01-01

    Heat transfer tests for the delta wing orbiter were conducted in a hypervelocity wind tunnel. A 1.1 percent scale model was tested at a Mach number of approximately 10.5 over an angle of attack range from 10 to 60 degrees over a length Reynolds number range from 5 times 10 to the 6th power to 24 times 10 to the 6th power. Heat transfer results were obtained from model surface heat gage measurements and thermographic phosphor paint. Limited pressure measurements were obtained.

  14. 14 CFR 25.1403 - Wing icing detection lights.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing icing detection lights. 25.1403... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Lights § 25.1403 Wing icing detection lights. Unless operations at night in known or forecast icing conditions are prohibited by...

  15. 14 CFR 25.1403 - Wing icing detection lights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing icing detection lights. 25.1403... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Lights § 25.1403 Wing icing detection lights. Unless operations at night in known or forecast icing conditions are prohibited by...

  16. 14 CFR 25.1403 - Wing icing detection lights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wing icing detection lights. 25.1403... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Lights § 25.1403 Wing icing detection lights. Unless operations at night in known or forecast icing conditions are prohibited by...

  17. Numerical calculation of the transonic flow past a swept wing

    NASA Technical Reports Server (NTRS)

    Jameson, A.; Caughey, D. A.

    1977-01-01

    A numerical method is presented for analyzing the transonic potential flow past a lifting, swept wing. A finite difference approximation to the full potential equation is solved in a coordinate system which is nearly conformally mapped from the physical space in planes parallel to the symmetry plane, and reduces the wing surface to a portion of one boundary of the computational grid. A coordinate invariant, rotated difference scheme is used, and the difference equations are solved by relaxation. The method is capable of treating wings of arbitrary planform and dihedral, although approximations in treating the tips and vortex sheet make its accuracy suspect for wings of small aspect ratio. Comparisons of calculated results with experimental data are shown for examples of both conventional and supercritical transport wings. Agreement is good for both types, but it was found necessary to account for the displacement effect of the boundary layer for the supercritical wing, presumably because of its greater sensitivity to changes in effective geometry.

  18. Wing-Wake Interactions between Ipsilateral Wings in Dragonfly Flight

    NASA Astrophysics Data System (ADS)

    Dong, Haibo; Liang, Zongxian

    2009-11-01

    Bilateral and ipsilateral wing-wing interactions can be commonly observed in insect flights. As a representative example of ipsilateral wing-wing interaction, dragonflies in flight have been widely studied. An important fact is that the flow over their hindwings is affected by the presence of the forewings. Wake capture and phase-change play very important role on aerodynamic performance of the hindwings We present a direct numerical simulation of a modeled dragonfly (Aeshna juncea) in slow flight as studied in Azuma et al (JEB 1985). Realistic morphologies of wing, body, and kinematics are used for maximum including wing and body features of a dragonfly. This work aims to study the relations between wake-topology and aerodynamic performance due to wing-wing and wing-wake interactions of dragonfly ipsilateral wings. DNS results are also compared with Local Momentum Theory (Azuma et al).

  19. Flying wings / flying fuselages

    NASA Technical Reports Server (NTRS)

    Wood, Richard M.; Bauer, Steven X. S.

    2001-01-01

    The present paper has documented the historical relationships between various classes of all lifting vehicles, which includes the flying wing, all wing, tailless, lifting body, and lifting fuselage. The diversity in vehicle focus was to ensure that all vehicle types that map have contributed to or been influenced by the development of the classical flying wing concept was investigated. The paper has provided context and perspective for present and future aircraft design studies that may employ the all lifting vehicle concept. The paper also demonstrated the benefit of developing an understanding of the past in order to obtain the required knowledge to create future concepts with significantly improved aerodynamic performance.

  20. Slotted Aircraft Wing

    NASA Technical Reports Server (NTRS)

    Vassberg, John C. (Inventor); Gea, Lie-Mine (Inventor); McLean, James D. (Inventor); Witowski, David P. (Inventor); Krist, Steven E. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    An aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one slot is defined by the wing during at least one transonic condition of the wing. The slot may either extend spanwise along only a portion of the wingspan, or it may extend spanwise along the entire wingspan. In either case, the slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  1. Servant's quarters, west wing, upper floor interior, looking to south. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Servant's quarters, west wing, upper floor interior, looking to south. Doorway at center connects with the Majordomo's sleeping space. - Vallejo Adobe, Adobe Road at Casa Grande, Petaluma, Sonoma County, CA

  2. Analysis of iced wings

    NASA Technical Reports Server (NTRS)

    Cebeci, T.; Chen, H. H.; Kaups, K.; Schimke, S.; Shin, J.

    1992-01-01

    A method for computing ice shapes along the leading edge of a wing and a method for predicting its aerodynamic performance degradation due to icing is described. Ice shapes are computed using an extension of the LEWICE code which was developed for airfoils. The aerodynamic properties of the iced wing are determined with an interactive scheme in which the solutions of the inviscid flow equations are obtained from a panel method and the solutions of the viscous flow equations are obtained from an inverse three-dimensional finite-difference boundary-layer method. A new interaction law is used to couple the inviscid and viscous flow solutions. The application of the LEWICE wing code to the calculation of ice shapes on a MS-317 swept wing shows good agreement with measurements. The interactive boundary-layer method is applied to a tapered ice wing in order to study the effect of icing on the aerodynamic properties of the wing at several angles of attack.

  3. Results of phase change heat transfer test OH51 using 0.006-scale space shuttle orbiter models 46-0 and 90-0 and partial wing 0.0175-scale model 64-0 in the LaRC 31-inch CFHT

    NASA Technical Reports Server (NTRS)

    Cummings, J. W.

    1977-01-01

    Test OH51 was a phase change paint test conducted in the LaRC 31-inch CFHT utilizing models 46-0, 64-0, and 90-0. Model 46-0 represented the space shuttle configuration 139 Orbiter. Model 90-0 represented the configuration 140 Orbiter. Model 64-0 represented the forward 45% portion of the Orbiter wing. The partial wing was tested with a shock generator located at various positions relative to the wing. The test was conducted at Mach 10.0, angles of attack from 27.5 deg through 37.5 deg, and Reynolds numbers of 0.5 and 1.5 million per foot.

  4. BMI Sandwich Wing Box Analysis and Test

    NASA Technical Reports Server (NTRS)

    Palm, Tod; Mahler, Mary; Shah, Chandu; Rouse, Marshall; Bush, Harold; Wu, Chauncey; Small, William J.

    2000-01-01

    A composite sandwich single bay wing box test article was developed by Northrop Grumman and tested recently at NASA Langley Research Center. The objectives for the wing box development effort were to provide a demonstration article for manufacturing scale up of structural concepts related to a high speed transport wing, and to validate the structural performance of the design. The box concept consisted of highly loaded composite sandwich wing skins, with moderately loaded composite sandwich spars. The dimensions of the box were chosen to represent a single bay of the main wing box, with a spar spacing of 30 inches, height of 20 inches constant depth, and length of 64 inches. The bismaleimide facesheet laminates and titanium honeycomb core chosen for this task are high temperature materials able to sustain a 300F service temperature. The completed test article is shown in Figure 1. The tests at NASA Langley demonstrated the structures ability to sustain axial tension and compression loads in excess of 20,000 lb/in, and to maintain integrity in the thermal environment. Test procedures, analysis failure predictions, and test results are presented.

  5. Optimization of Kinematics of a Flapping Wing Mechanism

    NASA Astrophysics Data System (ADS)

    George, Ryan; Thomson, Scott; Mattson, Christopher; Colton, Mark; Tree, Mike

    2010-11-01

    Flapping flight offers several potential advantages over conventional fixed wing flight, such as agility and maneuverability in confined spaces, potentially decreased noise and detectability, and hovering capability. In this presentation, a water tunnel-based flapping wing apparatus is introduced that allows for arbitrary wing trajectories in three rotational degrees of freedom and simultaneous measurements of lift and thrust production. An optimal flapping trajectory for takeoff is found using hardware-in-the-loop optimization methodology. Wing motion derived from high-speed imaging of a ladybug during takeoff is used as a first iteration of the hardware-in-the-loop optimization. Using real-time force measurements and a gradient-based optimization approach, the algorithm searches for the optimal trajectory for a variety of parameters such as lift or efficiency. Hardware performance is assessed. Results from the optimization routine, including the final flapping trajectory are reported for both rigid and compliant wings.

  6. Nonplanar wing load-line and slender wing theory

    NASA Technical Reports Server (NTRS)

    Deyoung, J.

    1977-01-01

    Nonplanar load line, slender wing, elliptic wing, and infinite aspect ratio limit loading theories are developed. These are quasi two dimensional theories but satisfy wing boundary conditions at all points along the nonplanar spanwise extent of the wing. These methods are applicable for generalized configurations such as the laterally nonplanar wing, multiple nonplanar wings, or wing with multiple winglets of arbitrary shape. Two dimensional theory infers simplicity which is practical when analyzing complicated configurations. The lateral spanwise distribution of angle of attack can be that due to winglet or control surface deflection, wing twist, or induced angles due to multiwings, multiwinglets, ground, walls, jet or fuselage. In quasi two dimensional theory the induced angles due to these extra conditions are likewise determined for two dimensional flow. Equations are developed for the normal to surface induced velocity due to a nonplanar trailing vorticity distribution. Application examples are made using these methods.

  7. Effects of Gravity on Wing Extension of Insects at Adult Eclosion

    NASA Astrophysics Data System (ADS)

    Hayashi, Fumio; Kishimoto, Naoko; Moriya, Hirofumi

    2008-06-01

    We compared the wing extensions of adult moths, Eterusia aedea, that emerged in either a horizontal plane, a vertical plane, or a vertical plane with centrifugal force generated by a rotating turntable. These studies were conducted to examine the relative importance of changes in fluid pressure from the body to the wings and gravitational force on the wings. The wings were generally crumpled when the insect emerged on the horizontal plane and became narrower when centrifugal acceleration was applied. In the future, observations of insect emergence in space at zero gravity are necessary to clarify the effects of gravity on wing extension.

  8. Theory of wing rock

    NASA Technical Reports Server (NTRS)

    Hsu, C. H.; Lan, C. E.

    1984-01-01

    A theory is developed for predicting wing rock characteristics. From available data, it can be concluded that wing rock is triggered by flow asymmetries, developed by negative or weakly positive roll damping, and sustained by nonlinear aerodynamic roll damping. A new nonlinear aerodynamic model that includes all essential aerodynamic nonlinearities is developed. The Beecham-Titchener method is applied to obtain approximate analytic solutions for the amplitude and frequency of the limit cycle based on the three degree-of-freedom equations of motion. An iterative scheme is developed to calculate the average aerodynamic derivatives and dynamic characteristics at limit cycle conditions. Good agreement between theoretical and experimental results is obtained.

  9. Status of wing flutter

    NASA Technical Reports Server (NTRS)

    Kussner, H G

    1936-01-01

    This report presents a survey of previous theoretical and experimental investigations on wing flutter covering thirteen cases of flutter observed on airplanes. The direct cause of flutter is, in the majority of cases, attributable to (mass-) unbalanced ailerons. Under the conservative assumption that the flutter with the phase angle most favorable for excitation occurs only in two degrees of freedom, the lowest critical speed can be estimated from the data obtained on the oscillation bench. Corrective measures for increasing the critical speed and for definite avoidance of wing flutter, are discussed.

  10. Winged cargo return vehicle conceptual design

    NASA Technical Reports Server (NTRS)

    1990-01-01

    NASA is committed to placing a permanent space station in Earth orbit in the 1990's. Space Station Freedom (SSF) will be located in a 220 n.m. orbit at 28.5 degrees inclination. The Winged Cargo Return Vehicle's (CRV) primary mission is to support SSF crew by flying regular resupply missions. The winged CRV is designed to be reusable, dry land recoverable, and unmanned. The CRV will be launched inline on three liquid hydrogen/oxygen rocket boosters with a payload capacity of 113,000 lbs. The three boosters will take the CRV to an orbit of 50 by 110 n.m. From this altitude the orbital manuevering engine will place the vehicle in synchronous orbit with the space station. The winged CRV will deliver cargo modules to the space station by direct docking or by remaining outside the SSF command zone and using the Orbital Maneuvering Vehicle (OMV) to transfer cargo. After unloading/loading, the CRV will deorbit and fly back to Kennedy Space Center. The CRV has a wing span of 57.8 feet, a length of 76.0 feet, and a dry weight of 61.5 klb. The cargo capacity of the vehicle is 44.4 klb. The vehicle has a lift-drag ratio of 1.28 (hypersonic) and 6.0 (subsonic), resulting in a 1351 n.m. cross range. The overall mission length ranges between 18.8 and 80.5 hr. The operational period will be the years 2000 to 2020.

  11. 14 CFR 23.572 - Metallic wing, empennage, and associated structures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Metallic wing, empennage, and associated structures. 23.572 Section 23.572 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Structure Fatigue Evaluation § 23.572 Metallic wing, empennage, and associated structures. (a) For...

  12. 14 CFR 23.572 - Metallic wing, empennage, and associated structures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Metallic wing, empennage, and associated structures. 23.572 Section 23.572 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Structure Fatigue Evaluation § 23.572 Metallic wing, empennage, and associated structures. (a) For...

  13. 14 CFR 23.572 - Metallic wing, empennage, and associated structures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Metallic wing, empennage, and associated structures. 23.572 Section 23.572 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Structure Fatigue Evaluation § 23.572 Metallic wing, empennage, and associated structures. (a) For...

  14. Active experiments in space plasmas; Symposium D4.1 of Commission D, COSPAR Scientific Assembly, 30th, Hamburg, Germany, July 11-21, 1994

    NASA Technical Reports Server (NTRS)

    Rietveld, M. T. (Editor)

    1995-01-01

    Papers from the conference are presented and cover the following topics: ion and electron beams; ionospheric modification; spacecraft interactions; chemical releases; and plasma waves. Auroras and plasma emissions are reported from electron beam injection experiments on the EXCEDE 3 rocket and APEX satellite respectively. The important parameters affecting the charging of spacecraft during the operation of electron guns is covered. The Active Magnetospheric Particle Acceleration Satellite (AMPAS) mission utilizing dual-payload tethered satellites and both up and downward directed electron beams is proposed to study the magnetosphere. Recent results and associated theories from the Sura, Arecibo and Troms ionospheric heating facitlites are presented. The effects of neutral gases on spacecraft charging are examined in a series of rocket flights. Many results from the Combined Release and Radiation Effects Satellite chemical release experiments are presented.

  15. Lift force of delta wings

    SciTech Connect

    Lee, M.; Ho, Chihming )

    1990-09-01

    On a delta wing, the separation vortices can be stationary due to the balance of the vorticity surface flux and the axial convection along the swept leading edge. These stationary vortices keep the wing from losing lift. A highly swept delta wing reaches the maximum lift at an angle of attack of about 40, which is more than twice as high as that of a two-dimensional airfoil. In this paper, the experimental results of lift forces for delta wings are reviewed from the perspective of fundamental vorticity balance. The effects of different operational and geometrical parameters on the performance of delta wings are surveyed.

  16. Foreign Travel Trip Report for LLNL travel with DOE FES funding,May 19th-30th, 2012

    SciTech Connect

    Joseph, I

    2012-07-05

    . The first studies of the implications for ITER (A. Kukushkin, ITER) have shown a great reduction in operational parameter space that, at present, can only be lifted by increasing target plate heat flux limits. During my visit to the CRPP at the EPFL, I delivered an invited talk in order to disseminate new results of the recent publication [1] on using non-axisymmetric perturbations of the SOL to control the edge plasma. I was given a tour of both the TCV tokamak and the TORPEX simple magnetized plasma device/divertor simulator. TORPEX is an excellent laboratory for exploring the physics of simple magnetized plasmas that are relevant to the scrape-off layer of a tokamak. Properly designed experiments on TORPEX can potentially be used to test the theory of controlling the edge plasma using non-axisymmetric potentials and currents in the SOL developed by LLNL described in [1].

  17. ``Schooling'' of wing pairs in flapping flight

    NASA Astrophysics Data System (ADS)

    Ramananarivo, Sophie; Zhang, Jun; Ristroph, Leif; AML, Courant Collaboration; Physics NYU Collaboration

    2015-11-01

    The experimental setup implements two independent flapping wings swimming in tandem. Both are driven with the same prescribed vertical heaving motion, but the horizontal motion is free, which means that the swimmers can take up any relative position and forward speed. Experiments show however clearly coordinated motions, where the pair of wings `crystallize' into specific stable arrangements. The follower wing locks into the path of the leader, adopting its speed, and with a separation distance that takes on one of several discrete values. By systematically varying the kinematics and wing size, we show that the set of stable spacings is dictated by the wavelength of the periodic wake structure. The forces maintaining the pair cohesion are characterized by applying an external force to the follower to perturb it away from the `stable wells'. These results show that hydrodynamics alone is sufficient to induce cohesive and coordinated collective locomotion through a fluid, and we discuss the hypothesis that fish schools and bird flocks also represent stable modes of motion.

  18. ACTE Wing Loads Analysis

    NASA Technical Reports Server (NTRS)

    Horn, Nicholas R.

    2015-01-01

    The Adaptive Compliant Trailing Edge (ACTE) project modified a Gulfstream III (GIII) aircraft with a new flexible flap that creates a seamless transition between the flap and the wing. As with any new modification, it is crucial to ensure that the aircraft will not become overstressed in flight. To test this, Star CCM a computational fluid dynamics (CFD) software program was used to calculate aerodynamic data for the aircraft at given flight conditions.

  19. Wing on a String

    ERIC Educational Resources Information Center

    Fitzgerald, Mike; Brand, Lance

    2004-01-01

    In this article, the authors present an activity that shows students how flight occurs. The "wing on a string" is a simple teacher-made frame that consists of PVC pipe, fishing line, and rubber bands--all readily available hardware store items. The only other materials/tools involved are a sheet of paper, some pieces of a soda straw, a stapler,…

  20. Aerodynamic cause of the asymmetric wing deformation of insect wings

    NASA Astrophysics Data System (ADS)

    Luo, Haoxiang; Tian, Fangbao; Song, Jialei; Lu, Xi-Yun

    2012-11-01

    Insect wings typically exhibit significant asymmetric deformation patterns, where the magnitude of deflection during upstroke is greater than during downstroke. Such a feature is beneficial for the aerodynamics since it reduces the projected wing area during upstroke and leads to less negative lift. Previously, this asymmetry has been mainly attributed to the directional bending stiffness in the wing structure, e.g., one-way hinge, or a pre-existing camber in the wing surface. In the present study, we demonstrate that the asymmetric pattern can also be caused by the asymmetric force due to the flow, while the wing structure and kinematics are symmetric. A two-dimensional translating/pitching wing in a free stream is used as the model, and the wing is represented by an elastic sheet with large displacement. The result shows that, interestingly, the wing experiences larger deformation during upstroke even though the aerodynamic force is greater during downstroke. The physical mechanism of the phenomenon can be explained by the modulating effect of the aerodynamic force on the timing of storage/release of the elastic energy in the wing. Supported by NSF (No. CBET-0954381).

  1. Wing shaping and strain sensing using fiber optics

    NASA Astrophysics Data System (ADS)

    Mendoza, Sergio Licon

    Current technologies to measure strain rely on strain gauges that become heavy with increased measurement points. One significant improvement is the Fiber Bragg Gratings (FBG) which allows light to reflect through a fiber optic line in relation to the strain applied on that fiber. Significant advantages over conventional strain gauges allow for a light weight detailed view of the strain applied to any structure containing these fibers. The SPACE Center in conjunction with the AERO Institute have produced preliminary conclusions on how to implement such fibers on a wing structure and how they could be used to control the shape of a wing. Such a wing structure could be built lighter and flexible than today's wings thus enabling a lighter aircraft. Further studies show that if a feedback mechanism is encompassed, flutter suppression techniques can be accomplished with the use of these fibers thus avoiding catastrophic failure.

  2. Fog spontaneously folds mosquito wings

    NASA Astrophysics Data System (ADS)

    Dickerson, Andrew K.; Liu, Xing; Zhu, Ting; Hu, David L.

    2015-02-01

    The flexibility of insect wings confers aerodynamic benefits, but can also present a hazard if exposed to fog or dew. Fog can cause water to accumulate on wings, bending them into tight taco shapes and rendering them useless for flight. In this combined experimental and theoretical study, we use high-speed video to film the spontaneous folding of isolated mosquito wings due to the evaporation of a water drop. We predict shapes of the deformed wing using two-dimensional elastica theory, considering both surface tension and Laplace pressure. We also recommend fold-resistant geometries for the wings of flapping micro-aerial vehicles. Our work reveals the mechanism of insect wing folding and provides a framework for further study of capillarity-driven folding in both natural and biomimetic systems at small scales.

  3. Wing flapping with minimum energy

    NASA Technical Reports Server (NTRS)

    Jones, R. T.

    1980-01-01

    A technique employed by Prandtl and Munk is adapted for the case of a wing in flapping motion to determine its lift distribution. The problem may be reduced to one of minimizing induced drag for a specified and periodically varying bending moment at the wing root. It is concluded that two wings in close tandem arrangement, moving in opposite phase, would eliminate the induced aerodynamic losses calculated

  4. Simulation of iced wing aerodynamics

    NASA Technical Reports Server (NTRS)

    Potapczuk, M. G.; Bragg, M. B.; Kwon, O. J.; Sankar, L. N.

    1991-01-01

    The sectional and total aerodynamic load characteristics of moderate aspect ratio wings with and without simulated glaze leading edge ice were studied both computationally, using a three dimensional, compressible Navier-Stokes solver, and experimentally. The wing has an untwisted, untapered planform shape with NACA 0012 airfoil section. The wing has an unswept and swept configuration with aspect ratios of 4.06 and 5.0. Comparisons of computed surface pressures and sectional loads with experimental data for identical configurations are given. The abrupt decrease in stall angle of attack for the wing, as a result of the leading edge ice formation, was demonstrated numerically and experimentally.

  5. Freight Wing Trailer Aerodynamics

    SciTech Connect

    Graham, Sean; Bigatel, Patrick

    2004-10-17

    Freight Wing Incorporated utilized the opportunity presented by this DOE category one Inventions and Innovations grant to successfully research, develop, test, patent, market, and sell innovative fuel and emissions saving aerodynamic attachments for the trucking industry. A great deal of past scientific research has demonstrated that streamlining box shaped semi-trailers can significantly reduce a truck's fuel consumption. However, significant design challenges have prevented past concepts from meeting industry needs. Market research early in this project revealed the demands of truck fleet operators regarding aerodynamic attachments. Products must not only save fuel, but cannot interfere with the operation of the truck, require significant maintenance, add significant weight, and must be extremely durable. Furthermore, SAE/TMC J1321 tests performed by a respected independent laboratory are necessary for large fleets to even consider purchase. Freight Wing used this information to create a system of three practical aerodynamic attachments for the front, rear and undercarriage of standard semi trailers. SAE/TMC J1321 Type II tests preformed by the Transportation Research Center (TRC) demonstrated a 7% improvement to fuel economy with all three products. If Freight Wing is successful in its continued efforts to gain market penetration, the energy and environmental savings would be considerable. Each truck outfitted saves approximately 1,100 gallons of fuel every 100,000 miles, which prevents over 12 tons of CO2 from entering the atmosphere. If all applicable trailers used the technology, the country could save approximately 1.8 billion gallons of diesel fuel, 18 million tons of emissions and 3.6 billion dollars annually.

  6. Self-induced wing rock of slender delta wings

    NASA Technical Reports Server (NTRS)

    Nguyen, L. T.; Yip, L. P.; Chambers, J. R.

    1981-01-01

    As part of a research program aimed at exploring basic mechanisms that cause wing rock in combat aircraft, an investigation was conducted to study the aerodynamic factors which cause the low-speed wing rock exhibited by slender delta wings. A flat-plate delta wing with 80 deg leading-edge sweep was subjected to conventional static-force tests and dynamic wind-tunnel experiments which included forced-oscillation, rotary, and free-to-roll tests. In addition, visualization of the flow phenomena involved was obtained by observing tuft patterns and using a helium-bubble technique. This paper summarizes the results of this study. Fundamental information is presented on the aerodynamic mechanisms that cause the wing rock and the problem of mathematically modeling the aerodynamics and motions is discussed.

  7. Control of a swept wing tailless aircraft through wing morphing

    NASA Astrophysics Data System (ADS)

    Guiler, Richard W.

    Inspired by flight in nature, work done by Lippisch, the Hortens, and Northrop offered insight to achieving the efficiency of bird flight with swept-wing tailless aircraft. Tailless designs must incorporate aerodynamic compromises for control, which have inhibited potential advantages. A morphing mechanism, capable of changing the twist of wing and that can also provide pitch, roll and yaw control for a tailless swept wing aircraft is the first step to a series of morphing techniques, which will lead to more fluid, bird-like flight. This research focuses on investigating the design of a morphing wing to improve the flight characteristics of swept wing Horten type tailless aircraft. Free flight demonstrators, wind tunnel flow visualization, wind-tunnel force and moment data along with CFD studies have been used to evaluate the stability, control and efficiency of a morphing swept wing tailless aircraft. A wing morphing mechanism for the control of a swept wing tailless aircraft has been developed. This new control technique was experimentally and numerically compared to an existing elevon equipped tailless aircraft and has shown the potential for significant improvement in efficiency. The feasibility of this mechanism was also validated through flight testing of a flight weight version. In the process of comparing the Horten type elevon equipped aircraft and the morphing model, formal wind tunnel verification of wingtip induced thrust, found in Horten (Bell Shaped Lift distribution) type swept wing tailless aircraft was documented. A more complete physical understanding of the highly complex flow generated in the control region of the morphing tailless aircraft has been developed. CFD models indicate the possibility of the presence of a Leading Edge Vortex (LEV) on the control section morphing wing when the tip is twisted between +3.5 degrees and +7 degrees. The presence of this LEV causes a reduction of drag while lift is increased. Similar LEVs have been

  8. The natural flow wing-design concept

    NASA Technical Reports Server (NTRS)

    Wood, Richard M.; Bauer, Steven X. S.

    1992-01-01

    A wing-design study was conducted on a 65 degree swept leading-edge delta wing in which the wing geometry was modified to take advantage of the naturally occurring flow that forms over a slender wing in a supersonic flow field. Three-dimensional nonlinear analysis methods were used in the study which was divided into three parts: preliminary design, initial design, and final design. In the preliminary design, the wing planform, the design conditions, and the near-conical wing-design concept were derived, and a baseline standard wing (conventional airfoil distribution) and a baseline near-conical wing were chosen. During the initial analysis, a full-potential flow solver was employed to determine the aerodynamic characteristics of the baseline standard delta wing and to investigate modifications to the airfoil thickness, leading-edge radius, airfoil maximum-thickness position, and wing upper to lower surface asymmetry on the baseline near-conical wing. The final design employed an Euler solver to analyze the best wing configurations found in the initial design and to extend the study of wing asymmetry to develop a more refined wing. Benefits resulting from each modification are discussed, and a final 'natural flow' wing geometry was designed that provides an improvement in aerodynamic performance compared with that of a baseline conventional uncambered wing, linear-theory cambered wing, and near-conical wing.

  9. Conceptual design of flapping-wing micro air vehicles.

    PubMed

    Whitney, J P; Wood, R J

    2012-09-01

    Traditional micro air vehicles (MAVs) are miniature versions of full-scale aircraft from which their design principles closely follow. The first step in aircraft design is the development of a conceptual design, where basic specifications and vehicle size are established. Conceptual design methods do not rely on specific knowledge of the propulsion system, vehicle layout and subsystems; these details are addressed later in the design process. Non-traditional MAV designs based on birds or insects are less common and without well-established conceptual design methods. This paper presents a conceptual design process for hovering flapping-wing vehicles. An energy-based accounting of propulsion and aerodynamics is combined with a one degree-of-freedom dynamic flapping model. Important results include simple analytical expressions for flight endurance and range, predictions for maximum feasible wing size and body mass, and critical design space restrictions resulting from finite wing inertia. A new figure-of-merit for wing structural-inertial efficiency is proposed and used to quantify the performance of real and artificial insect wings. The impact of these results on future flapping-wing MAV designs is discussed in detail. PMID:22498507

  10. Our Roots Feed Our Future: 30th Anniversary Conference of the Cornell Migrant Program. Presentations (May 22, 2002) = Nuestras raices nutren nuestro futuro: Conferencia del 30mo aniversario del Programa para Emigrantes de Cornell. Presentaciones (22 mayo 2002).

    ERIC Educational Resources Information Center

    State Univ. of New York, Ithaca. Coll. of Human Ecology at Cornell Univ.

    Presented in English and Spanish, this publication compiles 13 presentations at a conference celebrating the 30th anniversary of the Cornell Migrant Program. The entries examine experiences of migrant workers and children related to immigrating, finding work, enduring discrimination and police harassment, switching schools frequently, suffering…

  11. Beetle wings are inflatable origami

    NASA Astrophysics Data System (ADS)

    Chen, Rui; Ren, Jing; Ge, Siqin; Hu, David

    2015-11-01

    Beetles keep their wings folded and protected under a hard shell. In times of danger, they must unfold them rapidly in order for them to fly to escape. Moreover, they must do so across a range of body mass, from 1 mg to 10 grams. How can they unfold their wings so quickly? We use high-speed videography to record wing unfolding times, which we relate to the geometry of the network of blood vessels in the wing. Larger beetles have longer unfolding times. Modeling of the flow of blood through the veins successfully accounts for the wing unfolding speed of large beetles. However, smaller beetles have anomalously short unfolding times, suggesting they have lower blood viscosity or higher driving pressure. The use of hydraulics to unfold complex objects may have implications in the design of micro-flying air vehicles.

  12. Hydrodynamics of penguin wing models

    NASA Astrophysics Data System (ADS)

    Noca, Flavio; Cuong Duong, Nhut; Herpich, Jerome

    2010-11-01

    The three-dimensional kinematics of penguin wings were obtained from movie footage in aquariums. A 1:1 scale model of the penguin wing (with an identical planform but with a flat section profile and a rigid configuration) was actuated with a robotic arm in a water channel. The experiments were performed at a chord Reynolds number of about 10^4 (an order of magnitude lower than for the observed penguin). The dynamics of the wing were analyzed with force and flowfield measurements. The two main results are: 1. a net thrust on both the upstroke and downstroke movement; 2. the occurence of a leading edge vortex (LEV) along the wing span. The effects of section profile, wing flexibility, and a higher Reynolds number will be investigated in the future.

  13. Aeroelastic Analysis of Aircraft: Wing and Wing/Fuselage Configurations

    NASA Technical Reports Server (NTRS)

    Chen, H. H.; Chang, K. C.; Tzong, T.; Cebeci, T.

    1997-01-01

    A previously developed interface method for coupling aerodynamics and structures is used to evaluate the aeroelastic effects for an advanced transport wing at cruise and under-cruise conditions. The calculated results are compared with wind tunnel test data. The capability of the interface method is also investigated for an MD-90 wing/fuselage configuration. In addition, an aircraft trim analysis is described and applied to wing configurations. The accuracy of turbulence models based on the algebraic eddy viscosity formulation of Cebeci and Smith is studied for airfoil flows at low Mach numbers by using methods based on the solutions of the boundary-layer and Navier-Stokes equations.

  14. Nonlinear wave interactions in swept wing flows

    NASA Technical Reports Server (NTRS)

    Elhady, Nabil M.

    1988-01-01

    An analysis is presented which examines the modulation of different instability modes satisfying the triad resonance condition in time and space in a three-dimensional boundary layer flow. Detuning parameters are used for the wave numbers and the frequencies. The nonparallelism of the mean flow is taken into account in the analysis. At the leading-edge region of an infinite swept wing, different resonant triads are investigated that are comprised of travelling crossflow, vertical vorticity and Tollmein-Schlichting modes. The spatial evolution of the resonating triad components are studied.

  15. 4. PARTIAL WEST AND SOUTH SIDES. THE WING IN THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. PARTIAL WEST AND SOUTH SIDES. THE WING IN THE FOREGROUND IS NOT ORIGINAL, BUT WIDENED AND EXTENDED THE ORIGINAL SPACE AT THE LABORATORY'S WEST END. - U.S. Geological Survey, Rock Magnetics Laboratory, 345 Middlefield Road, Menlo Park, San Mateo County, CA

  16. Airplane wing vibrations due to atmospheric turbulence

    NASA Technical Reports Server (NTRS)

    Pastel, R. L.; Caruthers, J. E.; Frost, W.

    1981-01-01

    The magnitude of error introduced due to wing vibration when measuring atmospheric turbulence with a wind probe mounted at the wing tip was studied. It was also determined whether accelerometers mounted on the wing tip are needed to correct this error. A spectrum analysis approach is used to determine the error. Estimates of the B-57 wing characteristics are used to simulate the airplane wing, and von Karman's cross spectrum function is used to simulate atmospheric turbulence. It was found that wing vibration introduces large error in measured spectra of turbulence in the frequency's range close to the natural frequencies of the wing.

  17. Wing rotation and lift in SUEX flapping wing mechanisms

    NASA Astrophysics Data System (ADS)

    Mateti, Kiron; Byrne-Dugan, Rory A.; Tadigadapa, Srinivas A.; Rahn, Christopher D.

    2013-01-01

    This research presents detailed modeling and experimental testing of wing rotation and lift in the LionFly, a low cost and mass producible flapping wing mechanism fabricated monolithically from SUEX dry film and powered by piezoelectric bimorph actuators. A flexure hinge along the span of the wing allows the wing to rotate in addition to flapping. A dynamic model including aerodynamics is developed and validated using experimental testing with a laser vibrometer in air and vacuum, stroboscopic photography and high definition image processing, and lift measurement. The 112 mg LionFly produces 46° flap and 44° rotation peak to peak with 12° phase lag, which generates a maximum average lift of 71 μN in response to an applied sinusoidal voltage of 75 V AC and 75 V DC at 37 Hz. Simulated wing trajectories accurately predict measured wing trajectories at small voltage amplitudes, but slightly underpredict amplitude and lift at high voltage amplitudes. By reducing the length of the actuator, reducing the mechanism amplification and tuning the rotational hinge stiffness, a redesigned device is simulated to produce a lift to weight ratio of 1.5.

  18. Design of supercritical swept wings

    NASA Technical Reports Server (NTRS)

    Garabedian, P.; Mcfadden, G.

    1982-01-01

    Computational fluid dynamics are used to discuss problems inherent to transonic three-dimensional flow past supercritical swept wings. The formulation for a boundary value problem for the flow past the wing is provided, including consideration of weak shock waves and the use of parabolic coordinates. A swept wing code is developed which requires a mesh of 152 x 10 x 12 points and 200 time cycles. A formula for wave drag is calculated, based on the idea that the conservation form of the momentum equation becomes an entropy inequality measuring the drag, expressible in terms of a small-disturbance equation for a potential function in two dimensions. The entropy inequality has been incorporated in a two-dimensional code for the analysis of transonic flow over airfoils. A method of artificial viscosity is explored for optimum pressure distributions with design, and involves a free boundary problem considering speed over only a portion of the wing.

  19. Origin Story: Blended Wing Body

    NASA Video Gallery

    NASA is partnering with the Boeing Company, among others, to develop and test the blended wing body aircraft. The BWB has the potential to significantly reduce fuel use and noise. In this video, Bo...

  20. Embedded Wing Propulsion Conceptual Study

    NASA Technical Reports Server (NTRS)

    Kim, Hyun D.; Saunders, John D.

    2003-01-01

    As a part of distributed propulsion work under NASA's Revolutionary Aeropropulsion Concepts or RAC project, a new propulsion-airframe integrated vehicle concept called Embedded Wing Propulsion (EWP) is developed and examined through system and computational fluid dynamics (CFD) studies. The idea behind the concept is to fully integrate a propulsion system within a wing structure so that the aircraft takes full benefits of coupling of wing aerodynamics and the propulsion thrust stream. The objective of this study is to assess the feasibility of the EWP concept applied to large transport aircraft such as the Blended-Wing-Body aircraft. In this paper, some of early analysis and current status of the study are presented. In addition, other current activities of distributed propulsion under the RAC project are briefly discussed.

  1. The buzzing of flies' wings

    NASA Astrophysics Data System (ADS)

    Easton, Don

    1999-02-01

    The object of this science-fair project was to determine the wing-beat frequency of common house flies from the frequency of the sound produced when they buzz their wings. The data produced a pattern that I have seen many times and felt sure that I knew what was going on. Like many interesting and seemingly simple phenomena, the longer that I look at this one the more intriguing and less explicable it becomes.

  2. Oblique-wing supersonic aircraft

    NASA Technical Reports Server (NTRS)

    Jones, R. T. (Inventor)

    1976-01-01

    An aircraft including a single fuselage having a main wing and a horizontal stabilizer airfoil pivotally attached at their centers to the fuselage is described. The pivotal attachments allow the airfoils to be yawed relative to the fuselage for high speed flight, and to be positioned at right angles with respect to the fuselage during takeoff, landing, and low speed flight. The main wing and the horizontal stabilizer are upwardly curved from their center pivotal connections towards their ends to form curvilinear dihedrals.

  3. Results of experimental tests in the MSFC 14 x 14 inch trisonic wind tunnel on a .004 scale model space shuttle integrated vehicle 5 (model 77-O, 74-TS) to relieve wing loads during ascent (IA71)

    NASA Technical Reports Server (NTRS)

    Allen, E. C.

    1975-01-01

    Results are presented for the 0.004-scale orbiter, external tank, and solid rocket boosters combined as an integrated vehicle in a trisonic wind tunnel at mach numbers from 0.6 to 2.0. The primary test objective was to determine the effectiveness of several methods in relieving the Orbiter wing bending and torsion loads and moments during launch. Effects of several midwing spoilers, termed flipper doors, and Orbiter/external tank incidence were investigated. Photographs are included.

  4. Adaptive structures for fixed and rotary wing aircraft

    NASA Astrophysics Data System (ADS)

    Martin, Willi; Jänker, Peter; Siemetzki, Markus; Lorkowski, Thomas; Grohmann, Boris; Maier, Rudolf; Maucher, Christoph; Klöppel, Valentin; Enenkl, Bernhard; Roth, Dieter; Hansen, Heinz

    2007-07-01

    Since more than 10 years EADS Innovation Works, which is the corporate research centre of EADS (European Aeronautic Defence and Space Company), is investigating smart materials and adaptive structures for aircraft in cooperation with EADS business units. Focus of research efforts are adaptive systems for shape control, noise reduction and vibration control of both fixed and rotary wing aircraft as well as for lift optimisation of fixed wing aircraft. Two outstanding adaptive systems which have been pushed ahead in cooperation with Airbus Germany and Eurocopter Germany are adaptive servo flaps for helicopter rotor blades and innovative high lift devices for fixed wing aircraft which both were tested in flight for the first time representing world premieres. In this paper various examples of adaptive systems are presented which were developed and realized by EADS in recent years.

  5. Surface grid generation for wing-fuselage bodies

    NASA Technical Reports Server (NTRS)

    Smith, R. E.; Kudlinski, R. A.; Pitts, J. I.

    1984-01-01

    In the application of finite-difference methods to obtain numerical solutions of viscous compressible fluid flow about wing-fuselage bodies, it is advantageous to transform the governing equations to an idealized boundary-fitted coordinate system. The advantages are reduced computational complexity and added accuracy in the application of boundary conditions. The solution process requires that a grid be superimposed on the physical solution domain which corresponds to a uniform grid on a rectangular computational domain (uniform rectangular parallel-epiped). Grid generation is the determination of a one to one relationship between grid points in the physical domain and grid points in the computational domain. A technique for computing wing-fuselage surface grids using the Harris geometry and software for smooth-surface representation is described. Grid spacing control concepts which govern the relationship between the wing-fuselage surface and the computational grid are also presented.

  6. Numerical modeling of flexible insect wings using volume penalization

    NASA Astrophysics Data System (ADS)

    Engels, Thomas; Kolomenskiy, Dmitry; Schneider, Kai; Sesterhenn, Joern

    2012-11-01

    We consider the effects of chordwise flexibility on the aerodynamic performance of insect flapping wings. We developed a numerical method for modeling viscous fluid flows past moving deformable foils. It extends on the previously reported model for flows past moving rigid wings (J Comput Phys 228, 2009). The two-dimensional Navier-Stokes equations are solved using a Fourier pseudo-spectral method with the no-slip boundary conditions imposed by the volume penalization method. The deformable wing section is modeled using a non-linear beam equation. We performed numerical simulations of heaving flexible plates. The results showed that the optimal stroke frequency, which maximizes the mean thrust, is lower than the resonant frequency, in agreement with the experiments by Ramananarivo et al. (PNAS 108(15), 2011). The oscillatory part of the force only increases in amplitude when the frequency increases, and at the optimal frequency it is about 3 times larger than the mean force. We also study aerodynamic interactions between two heaving flexible foils. This flow configuration corresponds to the wings of dragonflies. We explore the effects of the phase difference and spacing between the fore- and hind-wing.

  7. Effects of leading-edge tubercles on wing flutter speeds.

    PubMed

    Ng, B F; New, T H; Palacios, R

    2016-06-01

    The dynamic aeroelastic effects on wings modified with bio-inspired leading-edge (LE) tubercles are examined in this study. We adopt a state-space aeroelastic model via the coupling of unsteady vortex-lattice method and a composite beam to evaluate stability margins as a result of LE tubercles on a generic wing. The unsteady aerodynamics and spanwise mass variations due to LE tubercles have counteracting effects on stability margins with the former having dominant influence. When coupled, flutter speed is observed to be 5% higher, and this is accompanied by close to 6% decrease in reduced frequencies as an indication of lower structural stiffness requirements for wings with LE tubercles. Both tubercle amplitude and wavelength have similar influences over the change in flutter speeds, and such modifications to the LE would have minimal effect on stability margins when concentrated inboard of the wing. Lastly, when used in sweptback wings, LE tubercles are observed to have smaller impacts on stability margins as the sweep angle is increased. PMID:27070824

  8. Dew-driven folding of insect wings

    NASA Astrophysics Data System (ADS)

    Dickerson, Andrew; Beadles, Sam; Clement, Courtney; Hu, David

    2013-11-01

    Small insect wings fold into tacos when exposed to dewfall or fog for extended times. Such shapes are tightly held together and require great force or long evaporation times for the wings to unfold. In this experimental investigation, we use time-lapse and high-speed videography on a mosquito wing exposed to fog to characterize the folding process from a flat wing to a taco. We observe a taco is formed through a series of processes involving wing bending, unbending, and subsequent tight folding of the wing following the sliding of the drop off the wing. We use a simplified 2D model to determine the forces coalescing drops exert on the wing, and present folding-resistant design suggestions for micro-aerial vehicle wings.

  9. Aerodynamic characteristics of scissor-wing geometries

    NASA Technical Reports Server (NTRS)

    Selberg, Bruce P.; Rokhsaz, Kamran; Housh, Clinton S.

    1991-01-01

    A scissor-wing configuration, consisting of two independently sweeping-wing surfaces, is compared with an equivalent fixed-wing geometry baseline over a wide Mach number range. The scissor-wing configuration is shown to have a higher total lift-to-drag ratio than the baseline in the subsonic region primarily due to the slightly higher aspect ratio of the unswept scissor wing. In the transonic region, the scissor wing is shown to have a higher lift-to-drag ratio than the baseline for values of lift coefficient greater than 0.35. It is also shown that, through the use of wing decalage, the lift of the two independent scissor wings can be equalized. In the supersonic regime, the zero lift wave drag of the scissor-wing at maximum sweep is shown to be 50 and 28 percent less than the zero lift wave drag of the baseline at Mach numbers 1.5 and 3.0, respectively. In addition, a pivot-wing configuration is introduced and compared with the scissor wing. The pivot-wing configuration is shown to have a slightly higher total lift-to-drag ratio than the scissor wing in the supersonic region due to the decreased zero lift wave drag of the pivot-wing configuration.

  10. Investigation into the Role of Dragonfly Wing Flexibility During Passive Wing Pitch Reversal

    NASA Astrophysics Data System (ADS)

    Bajwa, Yousaf; Williams, Ventress; Ren, Yan; Dong, Haibo; Flow Simulation Research Group Team

    2013-11-01

    Wing deformation is a characteristic part of flapping wing flight. In dragonflies, a torsion wave can be observed propagating from the tip to the root during stroke reversal. In this paper, we utilize high-speed photogrammetry and 3d surface reconstruction techniques to quantify wing deformation and kinematics of a dragonfly. We then use finite elements in the absolute nodal coordinate formulation to estimate strain energy in the wing during wing pitch reversal. We use this data to analyze the role of wing structure in facilitating wing rotation and bringing about the characteristic torsion wave. The influence of the elastic force in facilitating wing rotation is then compared with inertial and aerodynamic forces as well. A quantitative look into the variation of strain energy within the insect wing during wing rotation could lead to more efficient design of dynamic wing pitching mechanisms. Supported by NSF CBET-1343154.

  11. The aerodynamic effects of wing-wing interaction in flapping insect wings.

    PubMed

    Lehmann, Fritz-Olaf; Sane, Sanjay P; Dickinson, Michael

    2005-08-01

    We employed a dynamically scaled mechanical model of the small fruit fly Drosophila melanogaster (Reynolds number 100-200) to investigate force enhancement due to contralateral wing interactions during stroke reversal (the ;clap-and-fling'). The results suggest that lift enhancement during clap-and-fling requires an angular separation between the two wings of no more than 10-12 degrees . Within the limitations of the robotic apparatus, the clap-and-fling augmented total lift production by up to 17%, but depended strongly on stroke kinematics. The time course of the interaction between the wings was quite complex. For example, wing interaction attenuated total force during the initial part of the wing clap, but slightly enhanced force at the end of the clap phase. We measured two temporally transient peaks of both lift and drag enhancement during the fling phase: a prominent peak during the initial phase of the fling motion, which accounts for most of the benefit in lift production, and a smaller peak of force enhancement at the end fling when the wings started to move apart. A detailed digital particle image velocimetry (DPIV) analysis during clap-and-fling showed that the most obvious effect of the bilateral ;image' wing on flow occurs during the early phase of the fling, due to a strong fluid influx between the wings as they separate. The DPIV analysis revealed, moreover, that circulation induced by a leading edge vortex (LEV) during the early fling phase was smaller than predicted by inviscid two-dimensional analytical models, whereas circulation of LEV nearly matched the predictions of Weis-Fogh's inviscid model at late fling phase. In addition, the presence of the image wing presumably causes subtle modifications in both the wake capture and viscous forces. Collectively, these effects explain some of the changes in total force and lift production during the fling. Quite surprisingly, the effect of clap-and-fling is not restricted to the dorsal part of the

  12. Stretching Webb's Wings

    NASA Video Gallery

    Behind the Webb shows how the James Webb Space Telescope's protective sunshield will be folded up inside the rocket that carries it into orbit. Engineers explain to "Behind the Webb" how the sunshi...

  13. Aircraft wing structural detail design (wing, aileron, flaps, and subsystems)

    NASA Technical Reports Server (NTRS)

    Downs, Robert; Zable, Mike; Hughes, James; Heiser, Terry; Adrian, Kenneth

    1993-01-01

    The goal of this project was to design, in detail, the wing, flaps, and ailerons for a primary flight trainer. Integrated in this design are provisions for the fuel system, the electrical system, and the fuselage/cabin carry-through interface structure. This conceptual design displays the general arrangement of all major components in the wing structure, taking into consideration the requirements set forth by the appropriate sections of Federal Aviation Regulation Part 23 (FAR23) as well as those established in the statement of work.

  14. Effects of air breathing engine plumes on SSV orbiter subsonic wing pressure distribution, volume 2

    NASA Technical Reports Server (NTRS)

    Soard, T.

    1974-01-01

    Data presented were obtained during wind tunnel tests of a 0.0405-scale model of the -89B ferry configuration of the space shuttle vehicle orbiter. These tests were conducted in the Rockwell International low speed wind tunnel (NAAL). The primary test objective was to investigate orbiter wing pressure distributions resulting from nacelle plumes above and below the wing. Three six-engine nacelle configurations were tested. One configuration has a twin-podded nacelle mounted above each wing and the others had one mounted below each wing. Both had a centerline twin-podded nacelle mounted below the wing. Wing pressure distribution was determined by locating static pressure bugs on the upper and lower surfaces of the left wing. Pressure bugs were also located on the upper and lower surfaces of the body flap and on the B12 afterbody fairing when it was installed. Base and balance cavity pressures were recorded and a strain gage instrumented beam in the right wing measured elevon hinge moments and normal forces.

  15. Aeroelastic deployable wing simulation considering rotation hinge joint based on flexible multibody dynamics

    NASA Astrophysics Data System (ADS)

    Otsuka, Keisuke; Makihara, Kanjuro

    2016-05-01

    Morphing wings have been developed by several organizations for a variety of applications including the changing of flight ability while in the air and reducing the amount of space required to store an aircraft. One such example of morphing wings is the deployable wing that is expected to be used for Mars exploration. When designing wings, aeroelastic simulation is important to prevent the occurrence of destructive phenomena while the wing is in use. Flutter and divergence are typical issues to be addressed. However, it has been difficult to simulate the aeroelastic motion of deployable wings because of the significant differences between these deployable wings and conventional designs. The most apparent difference is the kinematic constraints of deployment, typically a hinge joint. These constraints lead not only to deformation but also to rigid body rotation. This research provides a novel method of overcoming the difficulties associated with handling these kinematic constraints. The proposed method utilizes flexible multibody dynamics and absolute nodal coordinate formulation to describe the dynamic motion of a deployable wing. This paper presents the simulation of the rigid body rotation around the kinematic constraints as induced by the aeroelasticity. The practicality of the proposed method is confirmed.

  16. Experimental Optimization of a Free-to-Rotate Wing for Small UAS

    NASA Technical Reports Server (NTRS)

    Logan, Michael J.; DeLoach, Richard; Copeland, Tiwana; Vo, Steven

    2014-01-01

    This paper discusses an experimental investigation conducted to optimize a free-to-rotate wing for use on a small unmanned aircraft system (UAS). Although free-to-rotate wings have been used for decades on various small UAS and small manned aircraft, little is known about how to optimize these unusual wings for a specific application. The paper discusses some of the design rationale of the basic wing. In addition, three main parameters were selected for "optimization", wing camber, wing pivot location, and wing center of gravity (c.g.) location. A small apparatus was constructed to enable some simple experimental analysis of these parameters. A design-of-experiment series of tests were first conducted to discern which of the main optimization parameters were most likely to have the greatest impact on the outputs of interest, namely, some measure of "stability", some measure of the lift being generated at the neutral position, and how quickly the wing "recovers" from an upset. A second set of tests were conducted to develop a response-surface numerical representation of these outputs as functions of the three primary inputs. The response surface numerical representations are then used to develop an "optimum" within the trade space investigated. The results of the optimization are then tested experimentally to validate the predictions.

  17. Space.

    ERIC Educational Resources Information Center

    Web Feet K-8, 2001

    2001-01-01

    This annotated subject guide to Web sites and additional resources focuses on space and astronomy. Specifies age levels for resources that include Web sites, CD-ROMS and software, videos, books, audios, and magazines; offers professional resources; and presents a relevant class activity. (LRW)

  18. The Nichols Wing Cutting Equipment

    NASA Technical Reports Server (NTRS)

    Ford, James B

    1923-01-01

    Described here is wing cutting equipment for the economical production of metal wings for wind tunnel models. The machine will make any size of constant-section wing or strut up to one-sixth inch chord by 36-inch span and up to a thickness of one and one-quarter inches. It cuts a smooth, true model that is accurate to within two-thousandths of an inch on any ordinate. The holding jaws are so designed as to leave the model free of chip marks, and the only hand finishing necessary after the cutting is a rub with amunite to remove burrs. The actual change on ordinate in this finishing rub is less than .0002 inches.

  19. Aircraft wing structure detail design

    NASA Technical Reports Server (NTRS)

    Sager, Garrett L.; Roberts, Ron; Mallon, Bob; Alameri, Mohamed; Steinbach, Bill

    1993-01-01

    The provisions of this project call for the design of the structure of the wing and carry-through structure for the Viper primary trainer, which is to be certified as a utility category trainer under FAR part 23. The specific items to be designed in this statement of work were Front Spar, Rear Spar, Aileron Structure, Wing Skin, and Fuselage Carry-through Structure. In the design of these parts, provisions for the fuel system, electrical system, and control routing were required. Also, the total weight of the entire wing planform could not exceed 216 lbs. Since this aircraft is to be used as a primary trainer, and the SOW requires a useful life of 107 cycles, it was decided that all of the principle stresses in the structural members would be kept below 10 ksi. The only drawback to this approach is a weight penalty.

  20. Formulas Pertinent to the Calculation of Flow-Field Effects at Supersonic Speeds Due to Wing Thickness

    NASA Technical Reports Server (NTRS)

    Margolis, Kenneth; Elliott, Miriam H.

    1959-01-01

    Expressions based on linearized supersonic-flow theory are derived for the perturbation velocity potential in space due to wing thickness for rectangular wings with biconvex airfoil sections and for arrow, delta, and quadrilateral wings with wedge-type airfoil sections. The complete range of supersonic speeds is considered subject to a minor aspect-ratio-Mach number restriction for the rectangular plan form and to the condition that the trailing edge is supersonic for the sweptback wings. The formulas presented can be utilized in determining the induced-flow characteristics at any point in the field and are readily adaptable for either numerical computation or analytical determination of any velocity components desired.

  1. Aerodynamic control with passively pitching wings

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Wood, Robert

    Flapping wings may pitch passively under aerodynamic and inertial loads. Such passive pitching is observed in flapping wing insect and robot flight. The effect of passive wing pitch on the control dynamics of flapping wing flight are unexplored. Here we demonstrate in simulation and experiment the critical role wing pitching plays in yaw control of a flapping wing robot. We study yaw torque generation by a flapping wing allowed to passively rotate in the pitch axis through a rotational spring. Yaw torque is generated through alternating fast and slow upstroke and and downstroke. Yaw torque sensitively depends on both the rotational spring force law and spring stiffness, and at a critical spring stiffness a bifurcation in the yaw torque control relationship occurs. Simulation and experiment reveal the dynamics of this bifurcation and demonstrate that anomalous yaw torque from passively pitching wings is the result of aerodynamic and inertial coupling between the pitching and stroke-plane dynamics.

  2. Results of experiments with slotted wings

    NASA Technical Reports Server (NTRS)

    Lachmann, G

    1924-01-01

    This report recounts some of the successful experiments conducted in England and Germany on slotted wings and ailerons. Wind tunnel test results are given and examples of aircraft constructed with these new wing components are described.

  3. Supersonic Wing Optimization Using SpaRibs

    NASA Technical Reports Server (NTRS)

    Locatelli, David; Mulani, Sameer B.; Liu, Qiang; Tamijani, Ali Y.; Kapania, Rakesh K.

    2014-01-01

    This research investigates the advantages of using curvilinear spars and ribs, termed SpaRibs, to design a supersonic aircraft wing-box in comparison to the use of classic design concepts that employ straight spars and ribs. The objective is to achieve a more efficient load-bearing mechanism and to passively control the deformation of the structure under the flight loads. Moreover, the use of SpaRibs broadens the design space and allows for natural frequencies and natural mode shape tailoring. The SpaRibs concept is implemented in a new optimization MATLAB-based framework referred to as EBF3SSWingOpt. This optimization scheme performs both the sizing and the shaping of the internal structural elements, connecting the optimizer with the analysis software. The shape of the SpaRibs is parametrically defined using the so called Linked Shape method. Each set of SpaRibs is placed in a one by one square domain of the natural space. The set of curves is subsequently transformed in the physical space for creating the wing structure geometry layout. The shape of each curve of each set is unique; however, mathematical relations link the curvature in an effort to reduce the number of design variables. The internal structure of a High Speed Commercial Transport aircraft concept developed by Boeing is optimized subjected to stress, subsonic flutter and supersonic flutter constraints. The results show that the use of the SpaRibs allows for the reduction of the aircraft's primary structure weight without violating the constraints. A weight reduction of about 15 percent is observed.

  4. Excess wings in broadband dielectric spectroscopy

    NASA Astrophysics Data System (ADS)

    Candelaresi, S.; Hilfer, R.

    2014-12-01

    Analysis of excess wings in broadband dielectric spectroscopy data of glass forming materials provides evidence for anomalous time evolutions and fractional semigroups. Solutions of fractional evolution equations in frequency space are used to fit dielectric spectroscopy data of glass forming materials with a range between 4 and 10 decades in frequency. It is shown that with only three parameters (two relaxation times plus one exponent) excellent fits can be obtained for 5-methyl-2-hexanol and for methyl-m-toluate over up to 7 decades. The traditional Havriliak-Negami fit with three parameters (two exponents and one relaxation time) fits only 4-5 decades. Using a second exponent, as in Havriliak-Negami fits, the α-peak and the excess wing can be modeled perfectly with our theory for up to 10 decades for all materials at all temperatures considered here. Traditionally this can only be accomplished by combining two Havriliak-Negami functions with 7 parameters. The temperature dependent relaxation times are fitted with the Vogel-Tammann-Fulcher relation which provides the corresponding Vogel-Fulcher temperatures. The relaxation times turn out to obey almost perfectly the Vogel-Tammann-Fulcher law. Computable expressions of time dependent relaxation functions are also reported.

  5. Flexible-Wing-Based Micro Air Vehicles

    NASA Technical Reports Server (NTRS)

    Ifju, Peter G.; Jenkins, David A.; Ettinger, Scott; Lian, Yong-Sheng; Shyy, Wei; Waszak, Martin R.

    2002-01-01

    This paper documents the development and evaluation of an original flexible-wing-based Micro Air Vehicle (MAV) technology that reduces adverse effects of gusty wind conditions and unsteady aerodynamics, exhibits desirable flight stability, and enhances structural durability. The flexible wing concept has been demonstrated on aircraft with wingspans ranging from 18 inches to 5 inches. Salient features of the flexible-wing-based MAV, including the vehicle concept, flexible wing design, novel fabrication methods, aerodynamic assessment, and flight data analysis are presented.

  6. Free wing assembly for an aircraft

    NASA Technical Reports Server (NTRS)

    Wolowicz, C. H. (Inventor)

    1978-01-01

    A free wing is attached to a fuselage of an aircraft in a manner such that the wing is free to pivot about a spanwise axis forward of its aerodynamic center. The wing is angularly displaced about the axis by aerodynamic pitching moments, resulting from lift, and is trimmed through a use of a trimmable free stabilizer comprising a floating canard mounted on a strut rigidly connected to the wing and projected forward from it.

  7. Cabin-fuselage-wing structural design concept with engine installation

    NASA Technical Reports Server (NTRS)

    Ariotti, Scott; Garner, M.; Cepeda, A.; Vieira, J.; Bolton, D.

    1993-01-01

    The purpose of this project is to provide a fuselage structural assembly and wing structural design that will be able to withstand the given operational parameters and loads provided by Federal Aviation Regulation Part 23 (FAR 23) and the Statement of Work (SOW). The goal is to provide a durable lightweight structure that will transfer the applied loads through the most efficient load path. Areas of producibility and maintainability of the structure will also be addressed. All of the structural members will also meet or exceed the desired loading criteria, along with providing adequate stiffness, reliability, and fatigue life as stated in the SOW. Considerations need to be made for control system routing and cabin heating/ventilation. The goal of the wing structure and carry through structure is also to provide a simple, lightweight structure that will transfer the aerodynamic forces produced by the wing, tailboom, and landing gear. These forces will be channeled through various internal structures sized for the pre-determined loading criteria. Other considerations were to include space for flaps, ailerons, fuel tanks, and electrical and control system routing. The difficulties encountered in the fuselage design include expanding the fuselage cabin to accept a third occupant in a staggered configuration and providing ample volume for their safety. By adding a third person the CG of aircraft will move forward so the engine needs to be moved aft to compensate for the difference in the moment. This required the provisions of a ring frame structure for the new position of the engine mount. The difficulties encountered in the wing structural design include resizing the wing for the increased capacity and weight, and compensating for a large torsion produced by the tail boom by placing a great number of stiffeners inside the boom, which will result in the relocation of the fuel tank. Finally, an adequate carry through structure for the wing and fuselage interface will be

  8. Expression of Genes Involved in Drosophila Wing Morphogenesis and Vein Patterning Are Altered by Spaceflight

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia A.; Hosamani, Ravikumar; Bhattacharya, Sharmila

    2015-01-01

    Imaginal wing discs of Drosophila melanogaster (fruit fly) defined during embryogenesis ultimately result in mature wings of stereotyped (specific) venation patterning. Major regulators of wing disc development are the epidermal growth factor receptor (EGF), Notch, Hedgehog (Hh), Wingless (Wg), and Dpp signaling pathways. Highly stereotyped vascular patterning is also characteristic of tissues in other organisms flown in space such as the mouse retina and leaves of Arabidopsis thaliana. Genetic and other adaptations of vascular patterning to space environmental factors have not yet been systematically quantified, despite widespread recognition of their critical importance for terrestrial and microgravity applications. Here we report changes in gene expression with space flight related to Drosophila wing morphogenesis and vein patterning. In addition, genetically modified phenotypes of increasingly abnormal ectopic wing venation in the Drosophila wing1 were analyzed by NASA's VESsel GENeration Analysis (VESGEN) software2. Our goal is to further develop insightful vascular mappings associated with bioinformatic dimensions of genetic or other molecular phenotypes for correlation with genetic and other molecular profiling relevant to NASA's GeneLab and other Space Biology exploration initiatives.

  9. X-Wing Research Vehicle

    NASA Technical Reports Server (NTRS)

    1986-01-01

    One of the most unusual experimental flight vehicles appearing at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center) in the 1980s was the Rotor Systems Research Aircraft (RSRA) X-Wing aircraft, seen here on the ramp. The craft was developed originally and then modified by Sikorsky Aircraft for a joint NASA-Defense Advanced Research Projects Agency (DARPA) program and was rolled out 19 August 1986. Taxi tests and initial low-altitude flight tests without the main rotor attached were carried out at Dryden before the program was terminated in 1988. The unusual aircraft that resulted from the Ames Research Center/Army X-Wing Project was flown at the Ames-Dryden Flight Research Facility (now Dryden Flight Research Center), Edwards, California, beginning in the spring of 1984, with a follow-on program beginning in 1986. The program, was conceived to provide an efficient combination of the vertical lift characteristic of conventional helicopters and the high cruise speed of fixed-wing aircraft. It consisted of a hybrid vehicle called the NASA/Army Rotor Systems Research Aircraft (RSRA), which was equipped with advanced X-wing rotor systems. The program began in the early 1970s to investigate ways to increase the speed of rotor aircraft, as well as their performance, reliability, and safety . It also sought to reduce the noise, vibration, and maintenance costs of helicopters. Sikorsky Aircraft Division of United Technologies Laboratories built two RSRA aircraft. NASA's Langley Research Center, Hampton, Virginia, did some initial testing and transferred the program to Ames Research Center, Mountain View, California, for an extensive flight research program conducted by Ames and the Army. The purpose of the 1984 tests was to demonstrate the fixed-wing capability of the helicopter/airplane hybrid research vehicle and explore its flight envelope and flying qualities. These tests, flown by Ames pilot G. Warren Hall and Army Maj (soon

  10. Output model-following control synthesis for an oblique-wing aircraft

    NASA Technical Reports Server (NTRS)

    Pahle, Joseph W.

    1990-01-01

    Recent interest in oblique-wing aircraft has focused on the potential aerodynamic performance advantage of a variable-skew oblique wing over a conventional or symmetric sweep wing. Unfortunately, the resulting asymmetric configuration has significant aerodynamic and inertial cross-coupling between the aircraft longitudinal and lateral-directional axes. Presented here is a decoupling control law synthesis technique that integrates stability augmentation, decoupling, and the direct incorporation of desired handling qualities into an output feedback controller. The proposed design technique uses linear quadratic regulator concepts in the framework of explicit model following. The output feedback strategy used is a suboptimal projection from the state space to the output space. Dynamics are then introduced into the controller to improve steady-state performance and increase system robustness. Closed-loop performance is shown by application of the control laws to the linearized equations of motion and nonlinear simulation of an oblique-wing aircraft.

  11. [Winged scapula in lyme borreliosis].

    PubMed

    Rausch, V; Königshausen, M; Gessmann, J; Schildhauer, T A; Seybold, D

    2016-06-01

    Here we present the case of a young patient with one-sided winged scapula and lyme borreliosis. This disease can be very delimitating in daily life. If non-operative treatment fails, dynamic or static stabilization of the scapula can be a therapeutic option. PMID:26849378

  12. The Wings for Angels Project

    ERIC Educational Resources Information Center

    McMillan, Liberty; McMillan, Ellen; Ayers, Ann

    2012-01-01

    How can the spirits of critically ill children be raised? Alexis Weisel (co-president of the Monarch High School National Art Honor Society, 2010-2011) had this question in mind when she initiated and developed the Wings for Angels Project after hearing about the Believe in Tomorrow (BIT) organization through her art teacher, Ellen McMillan. The…

  13. On Wings: Aerodynamics of Eagles.

    ERIC Educational Resources Information Center

    Millson, David

    2000-01-01

    The Aerodynamics Wing Curriculum is a high school program that combines basic physics, aerodynamics, pre-engineering, 3D visualization, computer-assisted drafting, computer-assisted manufacturing, production, reengineering, and success in a 15-hour, 3-week classroom module. (JOW)

  14. Rotary wing aerodynamically generated noise

    NASA Technical Reports Server (NTRS)

    Schmitz, F. J.; Morse, H. A.

    1982-01-01

    The history and methodology of aerodynamic noise reduction in rotary wing aircraft are presented. Thickness noise during hover tests and blade vortex interaction noise are determined and predicted through the use of a variety of computer codes. The use of test facilities and scale models for data acquisition are discussed.

  15. Polarization-Controllable Winged Nanocone Tip Antenna

    NASA Astrophysics Data System (ADS)

    Huttunen, Mikko J.; Mäkitalo, Jouni; Kauranen, Martti

    We propose winged metal nanocone optical antennas for efficient coupling of far-field radiation into the near-field of sharp metal tips. Unlike normal sharp metal tips, the winged nanocones require no oscillating field along the tip axis for the excitation of the tips. We calculate extinction spectra and local-field enhancements for single and winged gold nanocones and show that the field enhancements in the tips of the winged cones are due to a combination of particle plasmon resonances and a lightning-rod effect. We also propose that the winged nanocones could be used for optical far-field background suppression for tip-enhanced microscopy.

  16. F-8 oblique wing structural feasibility study

    NASA Technical Reports Server (NTRS)

    Koltko, E.; Katz, A.; Bell, M. A.; Smith, W. D.; Lauridia, R.; Overstreet, C. T.; Klapprott, C.; Orr, T. F.; Jobe, C. L.; Wyatt, F. G.

    1975-01-01

    The feasibility of fitting a rotating oblique wing on an F-8 aircraft to produce a full scale manned prototype capable of operating in the transonic and supersonic speed range was investigated. The strength, aeroelasticity, and fatigue life of such a prototype are analyzed. Concepts are developed for a new wing, a pivot, a skewing mechanism, control systems that operate through the pivot, and a wing support assembly that attaches in the F-8 wing cavity. The modification of the two-place NTF-8A aircraft to the oblique wing configuration is discussed.

  17. Rotor/wing aerodynamic interactions in hover

    NASA Technical Reports Server (NTRS)

    Felker, F. F.; Light, J. S.

    1986-01-01

    An experimental and theoretical investigation of rotor/wing aerodynamic interactions in hover is described. The experimental investigation consisted of both a large-scale and small-scale test. A 0.658-scale, V-22 rotor and wing was used in the large-scale test. Wind download, wing surface pressure, rotor performance, and rotor downwash data from the large-scale test are presented. A small-scale experiment was conducted to determine how changes in the rotor/wing geometry affected the aerodynamic interactions. These geometry variations included the distance between the rotor and wing, wing incidence angle, and configurations both with the rotor axis at the tip of the wing (tilt rotor configuration) and with the rotor axis at the center of the wing (compound helicopter configuration). A wing with boundary-layer control was also tested to evaluate the effect of leading and trailing edge upper surface blowing on the wing download. A computationally efficient, semi-empirical theory was developed to predict the download on the wing. Finally, correlations between the theoretical predictions and test data are presented.

  18. AST Composite Wing Program: Executive Summary

    NASA Technical Reports Server (NTRS)

    Karal, Michael

    2001-01-01

    The Boeing Company demonstrated the application of stitched/resin infused (S/RFI) composite materials on commercial transport aircraft primary wing structures under the Advanced Subsonic technology (AST) Composite Wing contract. This report describes a weight trade study utilizing a wing torque box design applicable to a 220-passenger commercial aircraft and was used to verify the weight savings a S/RFI structure would offer compared to an identical aluminum wing box design. This trade study was performed in the AST Composite Wing program, and the overall weight savings are reported. Previous program work involved the design of a S/RFI-base-line wing box structural test component and its associated testing hardware. This detail structural design effort which is known as the "semi-span" in this report, was completed under a previous NASA contract. The full-scale wing design was based on a configuration for a MD-90-40X airplane, and the objective of this structural test component was to demonstrate the maturity of the S/RFI technology through the evaluation of a full-scale wing box/fuselage section structural test. However, scope reductions of the AST Composite Wing Program pre-vented the fabrication and evaluation of this wing box structure. Results obtained from the weight trade study, the full-scale test component design effort, fabrication, design development testing, and full-scale testing of the semi-span wing box are reported.

  19. Piezoelectrically actuated insect scale flapping wing

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sujoy; Ganguli, Ranjan

    2010-04-01

    An energy method is used in order to derive the non-linear equations of motion of a smart flapping wing. Flapping wing is actuated from the root by a PZT unimorph in the piezofan configuration. Dynamic characteristics of the wing, having the same size as dragonfly Aeshna Multicolor, are analyzed using numerical simulations. It is shown that flapping angle variations of the smart flapping wing are similar to the actual dragonfly wing for a specific feasible voltage. An unsteady aerodynamic model based on modified strip theory is used to obtain the aerodynamic forces. It is found that the smart wing generates sufficient lift to support its own weight and carry a small payload. It is therefore a potential candidate for flapping wing of micro air vehicles.

  20. Locomotion by Tandem and Parallel Wings

    NASA Astrophysics Data System (ADS)

    Tanida, Yoshimichi

    A two-dimensional analysis was carried out on the locomotion by tandem and parallel wings in relation to the free flight of dragonflies and beetles, remarking the mutual interference between fore and hind wings. The results obtained are summarized as follows: In the case of tandem wings, (1)High thrust and propulsive efficiency can be achieved when the forewing oscillates with a definite phase lag behind the hindwing, as in the case of real dragonflies, (2)Somewhat smaller amplitude of hindwing leads to optimum condition for work sharing of two wings, (3)The hard forewing does not serve for the thrust and propulsive efficiency, whereas the hard hindwing does for the augmentation of them; In the case of parallel wings, (4)The hard wing placed near the soft wing acts nearly as an infinite plate, as for the ground effect, increasing both thrust and propulsive efficiency.

  1. Effect of wing inertia on hovering performance of flexible flapping wings

    NASA Astrophysics Data System (ADS)

    Yin, Bo; Luo, Haoxiang

    2010-11-01

    Insect wings in flight typically deform under the combined aerodynamic force and wing inertia; whichever is dominant depends on the mass ratio defined as m∗=ρsh/(ρfc), where ρsh is the surface density of the wing, ρf is the density of the air, and c is the characteristic length of the wing. To study the differences that the wing inertia makes in the aerodynamic performance of the deformable wing, a two-dimensional numerical study is applied to simulate the flow-structure interaction of a flapping wing during hovering flight. The wing section is modeled as an elastic plate, which may experience nonlinear deformations while flapping. The effect of the wing inertia on lift production, drag resistance, and power consumption is studied for a range of wing rigidity. It is found that both inertia-induced deformation and flow-induced deformation can enhance lift of the wing. However, the flow-induced deformation, which corresponds to the low-mass wing, produces less drag and leads to higher aerodynamic power efficiency. In addition, the wing deformation has a significant effect on the unsteady vortices around the wing. The implication of the findings on insect flight is discussed.

  2. Effects of Wing Platform on the Aerodynamic Performance of Finite-Span Flapping Wings

    NASA Astrophysics Data System (ADS)

    Yu, Meilin; Wang, Z. J.; Hu, Hui

    2010-11-01

    A numerical study is conducted to investigate the effects of wing platform on the aerodynamics performance of finite-span flapping wings. A three-dimensional high-order Navier-Stokes compressible flow solver was developed using the spectral difference method and dynamic grids. An AUSM^+-up Riemann solver was implemented to simulate the unsteady low Mach number flows over finite-span flapping wings with explicit third order Runge-Kutta time integration. The studied finite-span flapping wings, which include a rectangular flapping wing, an elliptic flapping wing and a bio-inspired flapping wing, have the same wing span, aspect ratio of the platform and the characteristics of the flapping motion (i.e., sinusoidal trajectory of the flapping wing tip, Strouhal number and reduced frequency). In the present study, the Strouhul number (Str) of the finite-span flapping wings was selected to be well within the optimal range usually used by flying insects and birds and swimming fishes (i.e., 0.2 < Str < 0.4). The effects of the wing platform on the aerodynamics performance of the finite-span flapping wings were elucidated in the terms of the evolutions and dynamic interaction between the leading edge vortices (LEV) and the wing tip vortices as well as the resultant aerodynamic forces (both lift and thrust) generated by the flapping wings.

  3. Wing spar stress charts and wing truss proportions

    NASA Technical Reports Server (NTRS)

    Warner, Edward P

    1926-01-01

    In order to simplify the calculation of beams continuous over three supports, a series of charts have been calculated giving the bending moments at all the critical points and the reactions at all supports for such members. Using these charts as a basis, calculations of equivalent bending moments, representing the total stresses acting in two bay-wing trusses of proportions varying over a wide range, have been determined, both with and without allowance for column effect. This leads finally to the determination of the best proportions for any particular truss or the best strut locations in any particular airplane. The ideal proportions are found to vary with the thickness of the wing section used, the aspect ratio, and the ratio of gap to chord.

  4. Similitude relations for buffet and wing rock on delta wings

    NASA Astrophysics Data System (ADS)

    Mabey, D. G.

    1997-08-01

    Vortex flow phenomena at high angles of incidence are of great interest to the designers of advanced combat aircraft. The steady phenomena (such as steady lift and pitching moments) are understood fairly well, whereas the unsteady phenomena are still uncertain. This paper addresses two important unsteady phenomena on delta wings. With regard to the frequency parameter of the quasi-periodic excitation caused by vortex bursting, a new correlation is established covering a range of sweep back from 60 to 75°. With regard to the much lower frequency parameter of limit-cycle rigid-body wing-rock, a new experiment shows conclusively that although the motion is non-linear, the frequency parameter can be predicted by quasi-steady theory. As a consequence, for a given sweep angle, the frequency parameter is inversely proportional to the square root of the inertia in roll. This is an important observation when attempting to extrapolate from model tests in wind tunnels to predict the wing-rock characteristics of aircraft.

  5. Nuclear Science Symposium, 30th, and Symposium on Nuclear Power Systems, 15th, San Francisco, CA, October 19-21, 1983, Proceedings

    NASA Technical Reports Server (NTRS)

    Nakamura, M. (Editor)

    1984-01-01

    The range of disciplines covered includes physics instrumentation, data acquisition, FASTBUS, radiation detectors, scintillators, photomultipliers and optical detectors, subnanosecond 2-D imaging, medical and health instrumentation, reactor instrumentation, and space instrumentation. Cerenkov detectors, the prevention and rate capability of breakdown processes in wire chambers, and an interactive parallel processor for data analysis are studied. Attention is also given to bismuth germanate's role in gamma-ray spectroscopy, and the construction of a broadband universal sampling head is described. Gamma-ray imaging with a rotating hexagonal uniform redundant array, and broadband X-ray astronomical spectrometry are considered.

  6. 14 CFR 23.572 - Metallic wing, empennage, and associated structures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Metallic wing, empennage, and associated structures. 23.572 Section 23.572 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Fatigue Evaluation §...

  7. 14 CFR 23.572 - Metallic wing, empennage, and associated structures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Metallic wing, empennage, and associated structures. 23.572 Section 23.572 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Fatigue Evaluation §...

  8. 14 CFR 45.25 - Location of marks on fixed-wing aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Location of marks on fixed-wing aircraft. 45.25 Section 45.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on...

  9. 14 CFR 45.25 - Location of marks on fixed-wing aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Location of marks on fixed-wing aircraft. 45.25 Section 45.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on...

  10. 14 CFR 45.25 - Location of marks on fixed-wing aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Location of marks on fixed-wing aircraft. 45.25 Section 45.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on...

  11. 14 CFR 45.25 - Location of marks on fixed-wing aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Location of marks on fixed-wing aircraft. 45.25 Section 45.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on...

  12. 14 CFR 45.25 - Location of marks on fixed-wing aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Location of marks on fixed-wing aircraft. 45.25 Section 45.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on...

  13. Aerodynamic effects of flexibility in flapping wings

    PubMed Central

    Zhao, Liang; Huang, Qingfeng; Deng, Xinyan; Sane, Sanjay P.

    2010-01-01

    Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast, wings flapping at high angles of attack generate stable leading edge vorticity, which persists throughout the duration of the stroke and enhances mean aerodynamic forces. Here, we show that aerodynamic forces can be controlled by altering the trailing edge flexibility of a flapping wing. We used a dynamically scaled mechanical model of flapping flight (Re ≈ 2000) to measure the aerodynamic forces on flapping wings of variable flexural stiffness (EI). For low to medium angles of attack, as flexibility of the wing increases, its ability to generate aerodynamic forces decreases monotonically but its lift-to-drag ratios remain approximately constant. The instantaneous force traces reveal no major differences in the underlying modes of force generation for flexible and rigid wings, but the magnitude of force, the angle of net force vector and centre of pressure all vary systematically with wing flexibility. Even a rudimentary framework of wing veins is sufficient to restore the ability of flexible wings to generate forces at near-rigid values. Thus, the magnitude of force generation can be controlled by modulating the trailing edge flexibility and thereby controlling the magnitude of the leading edge vorticity. To characterize this, we have generated a detailed database of aerodynamic forces as a function of several variables including material properties, kinematics, aerodynamic forces and centre of pressure, which can also be used to help validate computational models of aeroelastic flapping wings. These experiments will also be useful for wing design for small robotic

  14. Aerodynamic-structural study of canard wing, dual wing, and conventional wing systems for general aviation applications

    NASA Technical Reports Server (NTRS)

    Selberg, B. P.; Cronin, D. L.

    1985-01-01

    An analytical aerodynamic-structural airplane configuration study was conducted to assess performance gains achievable through advanced design concepts. The mission specification was for 350 mph, range of 1500 st. mi., at altitudes between 30,000 and 40,000 ft. Two payload classes were studied - 1200 lb (6 passengers) and 2400 lb (12 passengers). The configurations analyzed included canard wings, closely coupled dual wings, swept forward - swept rearward wings, joined wings, and conventional wing tail arrangements. The results illustrate substantial performance gains possible with the dual wing configuration. These gains result from weight savings due to predicted structural efficiencies. The need for further studies of structural efficiencies for the various advanced configurations was highlighted.

  15. Wing-wake interaction reduces power consumption in insect tandem wings

    NASA Astrophysics Data System (ADS)

    Lehmann, Fritz-Olaf

    Insects are capable of a remarkable diversity of flight techniques. Dragonflies, in particular, are notable for their powerful aerial manoeuvres and endurance during prey catching or territory flights. While most insects such as flies, bees and wasps either reduced their hinds wings or mechanically coupled fore and hind wings, dragonflies have maintained two independent-controlled pairs of wings throughout their evolution. An extraordinary feature of dragonfly wing kinematics is wing phasing, the shift in flapping phase between the fore and hind wing periods. Wing phasing has previously been associated with an increase in thrust production, readiness for manoeuvrability and hunting performance. Recent studies have shown that wing phasing in tandem wings produces a twofold modulation in hind wing lift, but slightly reduces the maximum combined lift of fore and hind wings, compared to two wings flapping in isolation. Despite this disadvantage, however, wing phasing is effective in improving aerodynamic efficiency during flight by the removal of kinetic energy from the wake. Computational analyses demonstrate that this increase in flight efficiency may save up to 22% aerodynamic power expenditure compared to insects flapping only two wings. In terms of engineering, energetic benefits in four-wing flapping are of substantial interest in the field of biomimetic aircraft design, because the performance of man-made air vehicles is often limited by high-power expenditure rather than by lift production. This manuscript provides a summary on power expenditures and aerodynamic efficiency in flapping tandem wings by investigating wing phasing in a dynamically scaled robotic model of a hovering dragonfly.

  16. Wing-wake interaction reduces power consumption in insect tandem wings

    NASA Astrophysics Data System (ADS)

    Lehmann, Fritz-Olaf

    2009-05-01

    Insects are capable of a remarkable diversity of flight techniques. Dragonflies, in particular, are notable for their powerful aerial manoeuvres and endurance during prey catching or territory flights. While most insects such as flies, bees and wasps either reduced their hinds wings or mechanically coupled fore and hind wings, dragonflies have maintained two independent-controlled pairs of wings throughout their evolution. An extraordinary feature of dragonfly wing kinematics is wing phasing, the shift in flapping phase between the fore and hind wing periods. Wing phasing has previously been associated with an increase in thrust production, readiness for manoeuvrability and hunting performance. Recent studies have shown that wing phasing in tandem wings produces a twofold modulation in hind wing lift, but slightly reduces the maximum combined lift of fore and hind wings, compared to two wings flapping in isolation. Despite this disadvantage, however, wing phasing is effective in improving aerodynamic efficiency during flight by the removal of kinetic energy from the wake. Computational analyses demonstrate that this increase in flight efficiency may save up to 22% aerodynamic power expenditure compared to insects flapping only two wings. In terms of engineering, energetic benefits in four-wing flapping are of substantial interest in the field of biomimetic aircraft design, because the performance of man-made air vehicles is often limited by high-power expenditure rather than by lift production. This manuscript provides a summary on power expenditures and aerodynamic efficiency in flapping tandem wings by investigating wing phasing in a dynamically scaled robotic model of a hovering dragonfly.

  17. Effects of wing deformation on aerodynamic performance of a revolving insect wing

    NASA Astrophysics Data System (ADS)

    Noda, Ryusuke; Nakata, Toshiyuki; Liu, Hao

    2014-12-01

    Flexible wings of insects and bio-inspired micro air vehicles generally deform remarkably during flapping flight owing to aerodynamic and inertial forces, which is of highly nonlinear fluid-structure interaction (FSI) problems. To elucidate the novel mechanisms associated with flexible wing aerodynamics in the low Reynolds number regime, we have built up a FSI model of a hawkmoth wing undergoing revolving and made an investigation on the effects of flexible wing deformation on aerodynamic performance of the revolving wing model. To take into account the characteristics of flapping wing kinematics we designed a kinematic model for the revolving wing in two-fold: acceleration and steady rotation, which are based on hovering wing kinematics of hawkmoth, Manduca sexta. Our results show that both aerodynamic and inertial forces demonstrate a pronounced increase during acceleration phase, which results in a significant wing deformation. While the aerodynamic force turns to reduce after the wing acceleration terminates due to the burst and detachment of leading-edge vortices (LEVs), the dynamic wing deformation seem to delay the burst of LEVs and hence to augment the aerodynamic force during and even after the acceleration. During the phase of steady rotation, the flexible wing model generates more vertical force at higher angles of attack (40°-60°) but less horizontal force than those of a rigid wing model. This is because the wing twist in spanwise owing to aerodynamic forces results in a reduction in the effective angle of attack at wing tip, which leads to enhancing the aerodynamics performance by increasing the vertical force while reducing the horizontal force. Moreover, our results point out the importance of the fluid-structure interaction in evaluating flexible wing aerodynamics: the wing deformation does play a significant role in enhancing the aerodynamic performances but works differently during acceleration and steady rotation, which is mainly induced by

  18. Flexible Wing Model for Structural Sizing and Multidisciplinary Design Optimization of a Strut-Braced Wing

    NASA Technical Reports Server (NTRS)

    Gern, Frank H.; Naghshineh, Amir H.; Sulaeman, Erwin; Kapania, Rakesh K.; Haftka, Raphael T.

    2000-01-01

    This paper describes a structural and aeroelastic model for wing sizing and weight calculation of a strut-braced wing. The wing weight is calculated using a newly developed structural weight analysis module considering the special nature of strut-braced wings. A specially developed aeroelastic model enables one to consider wing flexibility and spanload redistribution during in-flight maneuvers. The structural model uses a hexagonal wing-box featuring skin panels, stringers, and spar caps, whereas the aerodynamics part employs a linearized transonic vortex lattice method. Thus, the wing weight may be calculated from the rigid or flexible wing spanload. The calculations reveal the significant influence of the strut on the bending material weight of the wing. The use of a strut enables one to design a wing with thin airfoils without weight penalty. The strut also influences wing spanload and deformations. Weight savings are not only possible by calculation and iterative resizing of the wing structure according to the actual design loads. Moreover, as an advantage over the cantilever wing, employment of the strut twist moment for further load alleviation leads to increased savings in structural weight.

  19. Space vehicle

    NASA Technical Reports Server (NTRS)

    Vonpragenau, G. L. (Inventor)

    1975-01-01

    A space vehicle having an improved ascent configuration for use in traveling in space is presented. Components of the vehicle are: (1) a winged orbiter having an elongater fuselage and rearwardly directed main engines fixed to the fuselage; (2) an elongated tank assembly of an improved configuration disposed forwardly of the fuselage and connected with the main engines of the vehicle for supplying liquid propellants; and (3) a booster stage comprising a pair of integrated solid rocket boosters connected with the orbiter immediately beneath the fuselage and extended in substantial parallelism.

  20. Analytic Lyman-alpha wing diagnostics and the chromospheric excitation balance in cool dwarfs

    NASA Technical Reports Server (NTRS)

    Gayley, K. G.

    1994-01-01

    I show that the Lyman alpha wings of cool dwarfs can be understood in terms of a very simple model, based on a simplified representation of the chromospheric hydrogen excitation balance and approximate analytic wing diagnostics in partial redistribution. Much of the complexity of the radiation transfer in the partially coherent and steeply temperature-sensitive Lyman alpha line is circumvented by this technique. The result is an expedient scheme for inverting the Lyman alpha wing profile to determine the characteristic free electron density and its gradient in the middle chromosphere. This represents an important new diagnostic for constraining chromospheric models and their radiative losses. I apply this diagnostic to the Lyman alpha wing profiles of the Sun and AU Mic and show that current instrumentation, most notably the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope, is capable of providing the necessary data.

  1. Whistler wings from moving electrodes in a magnetized laboratory plasma

    SciTech Connect

    Urrutia, J.M.; Stenzel, R.L. )

    1989-05-01

    In a large laboratory plasma the current pattern set up by moving electrodes has been measured. It is observed that the current flow oblique to the magnetic field {rvec B}{sub o} at an angle given by the electrode speed across {rvec B}{sub o} and the current penetration along {rvec B}{sub o} which is controlled by whistler waves. The current pattern, characterized as whistler wings, occurs irrespective of whether the electrodes collect electrons/ions or emit fast electron beams. These results are relevant to active experiments in space involving electrodynamic tethers, beam injections and large space stations.

  2. Insect-like flapping wing mechanism based on a double spherical Scotch yoke.

    PubMed

    Galiński, Cezary; Zbikowski, Rafał

    2005-06-22

    We describe the rationale, concept, design and implementation of a fixed-motion (non-adjustable) mechanism for insect-like flapping wing micro air vehicles in hover, inspired by two-winged flies (Diptera). This spatial (as opposed to planar) mechanism is based on the novel idea of a double spherical Scotch yoke. The mechanism was constructed for two main purposes: (i) as a test bed for aeromechanical research on hover in flapping flight, and (ii) as a precursor design for a future flapping wing micro air vehicle. Insects fly by oscillating (plunging) and rotating (pitching) their wings through large angles, while sweeping them forwards and backwards. During this motion the wing tip approximately traces a "figure-of-eight" or a "banana" and the wing changes the angle of attack (pitching) significantly. The kinematic and aerodynamic data from free-flying insects are sparse and uncertain, and it is not clear what aerodynamic consequences different wing motions have. Since acquiring the necessary kinematic and dynamic data from biological experiments remains a challenge, a synthetic, controlled study of insect-like flapping is not only of engineering value, but also of biological relevance. Micro air vehicles are defined as flying vehicles approximately 150 mm in size (hand-held), weighing 50-100g, and are developed to reconnoitre in confined spaces (inside buildings, tunnels, etc.). For this application, insect-like flapping wings are an attractive solution and hence the need to realize the functionality of insect flight by engineering means. Since the semi-span of the insect wing is constant, the kinematics are spatial; in fact, an approximate figure-of-eight/banana is traced on a sphere. Hence a natural mechanism implementing such kinematics should be (i) spherical and (ii) generate mathematically convenient curves expressing the figure-of-eight/banana shape. The double spherical Scotch yoke design has property (i) by definition and achieves (ii) by tracing

  3. Rotor/Wing Interactions in Hover

    NASA Technical Reports Server (NTRS)

    Young, Larry A.; Derby, Michael R.

    2002-01-01

    Hover predictions of tiltrotor aircraft are hampered by the lack of accurate and computationally efficient models for rotor/wing interactional aerodynamics. This paper summarizes the development of an approximate, potential flow solution for the rotor-on-rotor and wing-on-rotor interactions. This analysis is based on actuator disk and vortex theory and the method of images. The analysis is applicable for out-of-ground-effect predictions. The analysis is particularly suited for aircraft preliminary design studies. Flow field predictions from this simple analytical model are validated against experimental data from previous studies. The paper concludes with an analytical assessment of the influence of rotor-on-rotor and wing-on-rotor interactions. This assessment examines the effect of rotor-to-wing offset distance, wing sweep, wing span, and flaperon incidence angle on tiltrotor inflow and performance.

  4. Constraints on the wing morphology of pterosaurs

    PubMed Central

    Palmer, Colin; Dyke, Gareth

    2012-01-01

    Animals that fly must be able to do so over a huge range of aerodynamic conditions, determined by weather, wind speed and the nature of their environment. No single parameter can be used to determine—let alone measure—optimum flight performance as it relates to wing shape. Reconstructing the wings of the extinct pterosaurs has therefore proved especially problematic: these Mesozoic flying reptiles had a soft-tissue membranous flight surface that is rarely preserved in the fossil record. Here, we review basic mechanical and aerodynamic constraints that influenced the wing shape of pterosaurs, and, building on this, present a series of theoretical modelling results. These results allow us to predict the most likely wing shapes that could have been employed by these ancient reptiles, and further show that a combination of anterior sweep and a reflexed proximal wing section provides an aerodynamically balanced and efficient theoretical pterosaur wing shape, with clear benefits for their flight stability. PMID:21957137

  5. A Discrete-Vortex Method for Studying the Wing Rock of Delta Wings

    NASA Technical Reports Server (NTRS)

    Gainer, Thomas G.

    2002-01-01

    A discrete-vortex method is developed to investigate the wing rock problem associated with highly swept wings. The method uses two logarithmic vortices placed above the wing to represent the vortex flow field and uses boundary conditions based on conical flow, vortex rate of change of momentum, and other considerations to position the vortices and determine their strengths. A relationship based on the time analogy and conical-flow assumptions is used to determine the hysteretic positions of the vortices during roll oscillations. Static and dynamic vortex positions and wing rock amplitudes and frequencies calculated by using the method are generally in good agreement with available experimental data. The results verify that wing rock is caused by hysteretic deflections of the vortices and indicate that the stabilizing moments that limit wing rock amplitudes are the result of the one primary vortex moving outboard of the wing where it has little influence on the wing.

  6. Effect of wing flexibility on the experimental aerodynamic characteristics of an oblique wing

    NASA Technical Reports Server (NTRS)

    Hopkins, E. J.; Yee, S. C.

    1977-01-01

    A solid-aluminum oblique wing was designed to deflect considerably under load so as to relieve the asymmetric spanwise stalling that is characteristic of this type of wing by creating washout on the trailing wing panel and washin on the leading wing panel. Experimental forces, and pitching, rolling and yawing moments were measured with the wing mounted on a body of revolution. In order to vary the dynamic pressure, measurements were made at several unit Reynolds numbers, and at Mach numbers. The wing was investigated when unswept (at subsonic Mach numbers only) and when swept 45 deg, 50 deg, and 60 deg. The wing was straight tapered in planform, had an aspect ratio of 7.9 (based on the unswept span), and a profile with a maximum thickness of 4 percent chord. The results substantiate the concept that an oblique wing designed with the proper amount of flexibility self relieves itself of asymmetric spanwise stalling and the associated nonlinear moment curves.

  7. Evaluation of installed performance of a wing-tip-mounted pusher turboprop on a semispan wing

    NASA Technical Reports Server (NTRS)

    Patterson, James C., Jr.; Bartlett, Glynn R.

    1987-01-01

    An exploratory investigation has been conducted at the Langley Research Center to determine the effect of a wing-tip-mounted pusher turboprop on the aerodynamic characteristics of a semispan wing. Tests were conducted on a semispan model with an upswept, untapered wing and an airdriven motor that powered an SR-2 high-speed propeller located on the tip of the wing as a pusher propeller. All tests were conducted at a Mach number of 0.70 over an angle-of-attack range from approximately -2 to 4 deg at a Reynolds number of 3.82 x 10 to the 6th based on the wing reference chord of 13 in. The data indicate that, as a result of locating the propeller behind the wing trailing edge at the wing tip in the crossflow of the wing-tip vortex, it is possible to improve propeller performance and simultaneously reduce the lift-induced drag.

  8. Elements of the Wing Section Theory and of the Wing Theory

    NASA Technical Reports Server (NTRS)

    Munk, Max M.

    1979-01-01

    Results are presented of the theory of wings and of wing sections which are of immediate practical value. They are proven and demonstrated by the use of the simple conceptions of kinetic energy and momentum only.

  9. Incompressible flutter characteristics of representative aircraft wings

    NASA Technical Reports Server (NTRS)

    Wilts, C H

    1958-01-01

    This report gives the results of a detailed study of the flutter characteristics of four representative aircraft wings. This study was made using the electric-analog computer at the California Institute of Technology. During the course of this investigation eight important parameters of each wing were varied and, in addition, the effects of mass, inertia, pitching spring, and location of a concentrated mass were investigated for all four wings and at several sweepback angles.

  10. Blue-winged teals in the waters around KSC

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The furious beating wings of a blue-winged teal launch it from the water as another swims calmly beneath it in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Inhabiting marshes, shallow ponds and lakes from British Columbia, Quebec and Newfoundland to North Carolina, the Gulf Coast and southern California, the teal winters as far south as South America. The 92,000-acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

  11. Probabilistic Structural Health Monitoring of the Orbiter Wing Leading Edge

    NASA Technical Reports Server (NTRS)

    Yap, Keng C.; Macias, Jesus; Kaouk, Mohamed; Gafka, Tammy L.; Kerr, Justin H.

    2011-01-01

    A structural health monitoring (SHM) system can contribute to the risk management of a structure operating under hazardous conditions. An example is the Wing Leading Edge Impact Detection System (WLEIDS) that monitors the debris hazards to the Space Shuttle Orbiter s Reinforced Carbon-Carbon (RCC) panels. Since Return-to-Flight (RTF) after the Columbia accident, WLEIDS was developed and subsequently deployed on board the Orbiter to detect ascent and on-orbit debris impacts, so as to support the assessment of wing leading edge structural integrity prior to Orbiter re-entry. As SHM is inherently an inverse problem, the analyses involved, including those performed for WLEIDS, tend to be associated with significant uncertainty. The use of probabilistic approaches to handle the uncertainty has resulted in the successful implementation of many development and application milestones.

  12. Remote pivot decoupler pylon: Wing/store flutter suppressor

    NASA Technical Reports Server (NTRS)

    Hassler, J. M., Jr. (Inventor)

    1986-01-01

    A device for suspending a store from an aerodynamic support surface, such an an aircraft wing, and more specifically, for improving upon singlet pivot decoupler pylons by reducing both frequency of active store, alignment, and alignment system space and power requirements. Two links suspend a lower pylon/rack section and releasable attached store from an upper pylon section mounted under the wing. The links allow the lower pylon section to rotate in pitch about a remote pivot point. A leaf spring connected between the lower section and electrical alignment system servomechanism provides pitch alignment of the lower section/store combination. The servomechanism utilizes an electric servomotor to drive the gear train and reversibly move the leaf spring, thereby maintaining the pitch attitude of the store within acceptable limits. The damper strokes when the lower section rotates to damp large oscillations of store.

  13. Optimal redesign study of the harm wing

    NASA Technical Reports Server (NTRS)

    Mcintosh, S. C., Jr.; Weynand, M. E.

    1984-01-01

    The purpose of this project was to investigate the use of optimization techniques to improve the flutter margins of the HARM AGM-88A wing. The missile has four cruciform wings, located near mid-fuselage, that are actuated in pairs symmetrically and antisymmetrically to provide pitch, yaw, and roll control. The wings have a solid stainless steel forward section and a stainless steel crushed-honeycomb aft section. The wing restraint stiffness is dependent upon wing pitch amplitude and varies from a low value near neutral pitch attitude to a much higher value at off-neutral pitch attitudes, where aerodynamic loads lock out any free play in the control system. The most critical condition for flutter is the low-stiffness condition in which the wings are moved symmetrically. Although a tendency toward limit-cycle flutter is controlled in the current design by controller logic, wing redesign to improve this situation is attractive because it can be accomplished as a retrofit. In view of the exploratory nature of the study, it was decided to apply the optimization to a wing-only model, validated by comparison with results obtained by Texas Instruments (TI). Any wing designs that looked promising were to be evaluated at TI with more complicated models, including body modes. The optimization work was performed by McIntosh Structural Dynamics, Inc. (MSD) under a contract from TI.

  14. High performance forward swept wing aircraft

    NASA Technical Reports Server (NTRS)

    Koenig, David G. (Inventor); Aoyagi, Kiyoshi (Inventor); Dudley, Michael R. (Inventor); Schmidt, Susan B. (Inventor)

    1988-01-01

    A high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first and second solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along with improved maneuverability and control of pitch, roll and yaw. Lift loss is delayed to higher angles of attack than in conventional aircraft. In one embodiment the ejectors may be advantageously positioned spanwise on the wing while the ductwork is kept to a minimum.

  15. The function of resilin in honeybee wings.

    PubMed

    Ma, Yun; Ning, Jian Guo; Ren, Hui Lan; Zhang, Peng Fei; Zhao, Hong Yan

    2015-07-01

    The present work aimed to reveal morphological characteristics of worker honeybee (Apis mellifera) wings and demonstrate the function of resilin on camber changes during flapping flight. Detailed morphological investigation of the wings showed that different surface characteristics appear on the dorsal and ventral side of the honeybee wings and the linking structure connecting the forewing and hindwing plays an indispensable role in honeybee flapping flight. Resilin stripes were found on both the dorsal and ventral side of the wings, and resilin patches mostly existed on the ventral side. On the basis of resilin distribution, five flexion lines and three cambered types around the lines of passive deformation of the coupled-wing profile were obtained, which defined the deformation mechanism of the wing along the chord, i.e. concave, flat plate and convex. From a movie obtained using high-speed photography from three orthogonal views of free flight in honeybees, periodic changes of the coupled-wing profile were acquired and further demonstrated that the deformation mechanism is a fundamental property for variable deformed shapes of the wing profile during flapping flight, and, in particular, the flat wing profile achieves a nice transition between downstrokes and upstrokes. PMID:25987733

  16. A magnetic fluid microdevice using insect wings

    NASA Astrophysics Data System (ADS)

    Sudo, S.; Tsuyuki, K.; Yano, T.; Takagi, K.

    2008-05-01

    A magnetic fluid microdevice using Diptera insect wings is proposed and constructed. The magnetic fluid device is composed of insect wings, a small permanent magnet, coil, and kerosene-based magnetic fluid. First, the structural properties of insect wings are studied through measurements of certain morphological parameters. Secondly, the novel type of microwind energy converter is constructed. Thirdly, the power generation characteristics of the magnetic fluid microdevice using insect wings are examined. It is found that the output power is roughly proportional to the cube of the airflow velocity.

  17. Subtractive Structural Modification of Morpho Butterfly Wings.

    PubMed

    Shen, Qingchen; He, Jiaqing; Ni, Mengtian; Song, Chengyi; Zhou, Lingye; Hu, Hang; Zhang, Ruoxi; Luo, Zhen; Wang, Ge; Tao, Peng; Deng, Tao; Shang, Wen

    2015-11-11

    Different from studies of butterfly wings through additive modification, this work for the first time studies the property change of butterfly wings through subtractive modification using oxygen plasma etching. The controlled modification of butterfly wings through such subtractive process results in gradual change of the optical properties, and helps the further understanding of structural optimization through natural evolution. The brilliant color of Morpho butterfly wings is originated from the hierarchical nanostructure on the wing scales. Such nanoarchitecture has attracted a lot of research effort, including the study of its optical properties, its potential use in sensing and infrared imaging, and also the use of such structure as template for the fabrication of high-performance photocatalytic materials. The controlled subtractive processes provide a new path to modify such nanoarchitecture and its optical property. Distinct from previous studies on the optical property of the Morpho wing structure, this study provides additional experimental evidence for the origination of the optical property of the natural butterfly wing scales. The study also offers a facile approach to generate new 3D nanostructures using butterfly wings as the templates and may lead to simpler structure models for large-scale man-made structures than those offered by original butterfly wings. PMID:26397977

  18. Wing Damage Effects on Dragonfly's maneuverability

    NASA Astrophysics Data System (ADS)

    Ning, Zhe; Gai, Kuo; Zeyghami, Samane; Dong, Haibo; Flow Simulation Research Group (FSRG) Team

    2011-11-01

    In this work, how the insect flight behavior contributes to its adaptability to limited performance condition is studied through a combined experimental and computational study. High speed photogrammetry is used to collect the data of dragonflies' takeoffs with intact and damaged wings along the chord and span separately. Then the effect of the spanwise and chordwise damage on the dragonfly wing is investigated. Results show that both changes have different effects on the wing and body kinematics and the merit of maneuverability. Two theories will be introduced to explain the wing damage tolerance behavior of the dragonfly flight. This work is supported by NSF CBET-1055949.

  19. The supercritical profile of the supercritical wing

    NASA Technical Reports Server (NTRS)

    Wagner, O.

    1981-01-01

    The profile wing design for supercritical structures is discussed. Emphasis is placed on the flow of air surrounding the wing and variations in flow fields are examined. Modifications to the profile for flight below transonic level are presented that increase the uplift pressure and permit the achievement of critical Mach numbers on the order of 0.85. The uplift pressure along the upper side of the profile is compared for a classical and a Peaky profile. A comparison of classical and supercritical wing cross sections indicates a flatter upper side, a large nose radius, and a thicker profile to the supercritical wing.

  20. Projection Moire Interferometry Measurements of Micro Air Vehicle Wings

    NASA Technical Reports Server (NTRS)

    Fleming, Gary A.; Bartram, Scott M.; Waszak, Martin R.; Jenkins, Luther N.

    2001-01-01

    Projection Moire Interferometry (PMI) has been used to measure the structural deformation of micro air vehicle (MAV) wings during a series of wind tunnel tests. The MAV wings had a highly flexible wing structure, generically reminiscent of a bat s wing, which resulted in significant changes in wing shape as a function of MAV angle-of-attack and simulated flight speed. This flow-adaptable wing deformation is thought to provide enhanced vehicle stability and wind gust alleviation compared to rigid wing designs. Investigation of the potential aerodynamic benefits of a flexible MAV wing required measurement of the wing shape under aerodynamic loads. PMI was used to quantify the aerodynamically induced changes in wing shape for three MAV wings having different structural designs and stiffness characteristics. This paper describes the PMI technique, its application to MAV testing, and presents a portion of the PMI data acquired for the three different MAV wings tested.

  1. Projection moire interferometry measurements of micro air vehicle wings

    NASA Astrophysics Data System (ADS)

    Fleming, Gary A.; Bartram, Scott M.; Waszak, Martin R.; Jenkins, Luther N.

    2001-11-01

    Projection Moire Interferometry (PMI) has been used to measure the structural deformation of micro air vehicle (MAV) wings during a series of wind tunnel tests. The MAV wings had a highly flexible wing structure, generically reminiscent of a bat's wing, which resulted in significant changes in wing shape as a function of MAV angle-of-attack and simulated flight speed. This flow-adaptable wing deformation is thought to provide enhanced vehicle stability and wind gust alleviation compared to rigid wing designs. Investigation of the potential aerodynamic benefits of a flexible MAV wing required measurement of the wing shape under aerodynamic loads. PMI was used to quantify the aerodynamically induced changes in wing shape for three MAV wings having different structural designs and stiffness characteristics. This paper describes the PMI technique, its application to MAV testing, and presents a portion of the PMI data acquired for the three different MAV wings tested.

  2. On wings and keels (2)

    NASA Astrophysics Data System (ADS)

    Slooff, J. W.

    1985-05-01

    The physical mechanisms governing the hydrodynamics of sailing yacht keels and the parameters that, through these mechanisms, determine keel performance are discussed. It is concluded that due to the presence of the free water surface optimum keel shapes differ from optimum shapes for aircraft wings. Utilizing computational fluid dynamics analysis and optimization it is found that the performance of conventional keels can be improved significantly by reducing taper or even applying inverse taper (upside-down keel) and that decisive improvements in performance can be realized through keels with winglets.

  3. Lattice Boltzmann simulation of dynamics of plunge and pitch of 3D flexible wing

    NASA Astrophysics Data System (ADS)

    Qi, Dewei; Shyy, Wei

    2008-11-01

    The method of lattice Boltzmann (LB) simulation has been used to simulate fluid structures and motion of a flexible insect wing in a 3D space. In the method, a beam has been discretized into a chain of rigid segments. Each segment is connected through ball and socket joints at its ends. One segment may be bent and twisted with its neighboring segment. A constraint force is applied to each joint to ensure the solid structure moving as a whole flexible elastic body.We have demonstrated that the LB method is suitable for modeling of aerodynamics of insects flight at low Reynolds numbers. First, a simulation of plunging and pitching of a rigid wing is performed at Re=75 in a 2D space and the results of lift forces and flow structures are in excellent agreement with the previous results. Second, plunging and pitching of a flexible wing in span-wise direction is simulated at Re=136 in a 3D space. We found that when twisting elasticity is large enough the twisting angle could be controlled at a level of smaller than 0.2 degree. It is shown that as bending and twisting elasticity is large enough, the motion of flexible wing approaches that of a rigid membrane wing. The simulation results show that the optimization of flexibility in span-wise direction will benefit thrust and an intermediate level is favorable. The results are consistent with experimental finding.

  4. Effects of air breathing engine plumes on SSV orbiter subsonic wing pressure distribution (OA57B), volume 1

    NASA Technical Reports Server (NTRS)

    Soard, T.

    1974-01-01

    Data were obtained during wind tunnel tests of a 0.0405-scale model of the ferry configuration of the space shuttle vehicle orbiter conducted in a low speed wind tunnel during the time period of September 18 to September 23, 1973. The primary test objective was to investigate orbiter wing pressure distributions resulting from nacelle plumes above and below the wing. Three six-engine nacelle configurations were tested. One configuration had a twin-podded nacelle mounted above each wing and the others had one mounted below each wing. Both had a centerline twin-podded nacelle mounted below the wing. Wing pressure distribution was determined by locating static pressure bugs on the upper and lower surfaces of the left wing. Pressure bugs were also located on the upper and lower surfaces of the body flap and on the B12 afterbody fairing when it was installed. Base and balance cavity pressures were recorded and a strain gage instrumented beam in the right wing measured elevon hinge moments and normal forces.

  5. The Aerodynamic Aspect of Wing-fuselage Fillets

    NASA Technical Reports Server (NTRS)

    Muttray, H

    1935-01-01

    Model tests prove the feasibility of enhancing the aerodynamic qualities of wing-fuselage fillets by appropriate design of fuselage and wing roots. Abrupt changes from maximum fuselage height to wing chord must be avoided and every longitudinal section of fuselage and wing roots must be so faired and arranged as to preserve the original lift distribution of the continuous wing. Adapting the fuselage to the curvilinear circulation of the wing affords further improvement. The polars of such arrangements are almost the same as those of the "wing alone," thus voiding the superiority of the high-wing type airplane known with conventional design.

  6. An aerodynamic model for one and two degree of freedom wing rock of slender delta wings

    NASA Technical Reports Server (NTRS)

    Hong, John

    1993-01-01

    The unsteady aerodynamic effects due to the separated flow around slender delta wings in motion were analyzed. By combining the unsteady flow field solution with the rigid body Euler equations of motion, self-induced wing rock motion is simulated. The aerodynamic model successfully captures the qualitative characteristics of wing rock observed in experiments. For the one degree of freedom in roll case, the model is used to look into the mechanisms of wing rock and to investigate the effects of various parameters, like angle of attack, yaw angle, displacement of the separation point, and wing inertia. To investigate the roll and yaw coupling for the delta wing, an additional degree of freedom is added. However, no limit cycle was observed in the two degree of freedom case. Nonetheless, the model can be used to apply various control laws to actively control wing rock using, for example, the displacement of the leading edge vortex separation point by inboard span wise blowing.

  7. Effect of wing flexibility on phasing of tandem wings in forward flight

    NASA Astrophysics Data System (ADS)

    Naidu, Vishal; Young, John; Lai, Joseph

    2014-11-01

    The dragonfly with two pairs of wings in tandem uses different phases between the wing pairs to suit the needs of the flight. Previous studies to understand the effect of phasing in forward flight are based on rigid wings. This is in contrast to the highly flexible dragonfly wings, with varying spanwise and chordwise flexibility. Here, we study flexible flapping wing simulations using Fluid Structure Interaction (FSI) in forward flight, at an advance ratio of 0.3 and Reynolds number of approximately 1300. The FSI simulations are carried out for phase 90° (hindwing leading), 0° (in-phase) and 180° (anti-phase). The performance of flexible wings will be compared with that of the rigid wings and the effect of flexibility will be discussed. PhD Student.

  8. Wing Deployment Sequence #2: The deployable, inflatable wing technology demonstrator experiment airc

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Wing Deployment Sequence #2: The deployable, inflatable wing technology demonstrator experiment aircraft's wings continue deploying following separation from its carrier aircraft during a flight conducted by the NASA Dryden Flight Research Center, Edwards, California. The inflatable wing project represented a basic flight research effort by Dryden personnel. Three successful flights of the I2000 inflatable wing aircraft occurred. During the flights, the team air-launched the radio-controlled (R/C) I2000 from an R/C utility airplane at an altitude of 800-1000 feet. As the I2000 separated from the carrier aircraft, its inflatable wings 'popped-out,' deploying rapidly via an on-board nitrogen bottle. The aircraft remained stable as it transitioned from wingless to winged flight. The unpowered I2000 glided down to a smooth landing under complete control.

  9. Wing Deployment Sequence #1: The deployable, inflatable wing technology demonstrator experiment airc

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Wing Deployment Sequence #1: The deployable, inflatable wing technology demonstrator experiment aircraft's wings begin deploying following separation from its carrier aircraft during a flight conducted by the NASA Dryden Flight Research Center, Edwards, California. The inflatable wing project represented a basic flight research effort by Dryden personnel. Three successful flights of the I2000 inflatable wing aircraft occurred. During the flights, the team air-launched the radio-controlled (R/C) I2000 from an R/C utility airplane at an altitude of 800-1000 feet. As the I2000 separated from the carrier aircraft, its inflatable wings 'popped-out,' deploying rapidly via an on-board nitrogen bottle. The aircraft remained stable as it transitioned from wingless to winged flight. The unpowered I2000 glided down to a smooth landing under complete control.

  10. Wing Deployment Sequence #3: The deployable, inflatable wing technology demonstrator experiment airc

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Wing Deployment Sequence #3: The deployable, inflatable wing technology demonstrator experiment aircraft's wings fully deployed during flight following separation from its carrier aircraft during a flight conducted by the NASA Dryden Flight Research Center, Edwards, Californiaornia. The inflatable wing project represented a basic flight research effort by Dryden personnel. Three successful flights of the I2000 inflatable wing aircraft occurred. During the flights, the team air-launched the radio-controlled (R/C) I2000 from an R/C utility airplane at an altitude of 800-1000 feet. As the I2000 separated from the carrier aircraft, its inflatable wings 'popped-out,' deploying rapidly via an on-board nitrogen bottle. The aircraft remained stable as it transitioned from wingless to winged flight. The unpowered I2000 glided down to a smooth landing under complete control.

  11. Effect of leading edge roundness on a delta wing in wing-rock motion

    NASA Technical Reports Server (NTRS)

    Ng, T. Terry; Malcolm, Gerald N.

    1990-01-01

    The effect of wing leading-edge roundness on wing rock was investigated using flow visualization in a water tunnel. Eighty degree delta wing models were tested on free-to-roll and forced oscillation rigs. The onset of wing rock was delayed by increasing the roundness of the leading edges. The wing rock amplitude and frequency results suggested that damping was increased at lower angles of attack but reduced at higher angles of attack. Vortex lift-off and vortex breakdown, especially during dynamic situations, were strongly affected by the leading edge roundness. Different forms of wing rock motion could be sustained by combinations of vortex breakdown and vortex lift-off. Behaviors of the wing and vortex motions were explained by the influence of leading edge roundness on the separation location, vortex trajectory, and vortex breakdown.

  12. Advanced wing design survivability testing and results

    NASA Technical Reports Server (NTRS)

    Bruno, J.; Tobias, M.

    1992-01-01

    Composite wings on current operational aircraft are conservatively designed to account for stress/strain concentrations, and to assure specified damage tolerance. The technology that can lead to improved composite wing structures and associated structural efficiency is to increase design ultimate strain levels beyond their current limit of 3500 to 4000 micro-in/in to 6000 micro-in/in without sacrificing structural integrity, durability, damage tolerance, or survivability. Grumman, under the sponsorship of the Naval Air Development Center (NADC), has developed a high-strain composite wing design for a subsonic aircraft wing using novel and innovative design concepts and manufacturing methods, while maintaining a state-of-the-art fiber/resin system. The current advanced wing design effort addressed a tactical subsonic aircraft wing using previously developed, high-strain wing design concepts in conjunction with newer/emerging fiber and polymer matrix composite (PMC) materials to achieve the same goals, while reducing complexity. Two categories of advanced PMC materials were evaluated: toughened thermosets; and engineered thermoplastics. Advanced PMC materials offer the technological opportunity to take maximum advantage of improved material properties, physical characteristics, and tailorability to increase performance and survivability over current composite structure. Damage tolerance and survivability to various threats, in addition to structural integrity and durability, were key technical issues addressed during this study, and evaluated through test. This paper focuses on the live-fire testing, and the results performed to experimentally evaluate the survivability of the advanced wing design.

  13. Computer Code Aids Design Of Wings

    NASA Technical Reports Server (NTRS)

    Carlson, Harry W.; Darden, Christine M.

    1993-01-01

    AERO2S computer code developed to aid design engineers in selection and evaluation of aerodynamically efficient wing/canard and wing/horizontal-tail configurations that includes simple hinged-flap systems. Code rapidly estimates longitudinal aerodynamic characteristics of conceptual airplane lifting-surface arrangements. Developed in FORTRAN V on CDC 6000 computer system, and ported to MS-DOS environment.

  14. Biaxial mechanical characterization of bat wing skin.

    PubMed

    Skulborstad, A J; Swartz, S M; Goulbourne, N C

    2015-06-01

    The highly flexible and stretchable wing skin of bats, together with the skeletal structure and musculature, enables large changes in wing shape during flight. Such compliance distinguishes bat wings from those of all other flying animals. Although several studies have investigated the aerodynamics and kinematics of bats, few have examined the complex histology and mechanical response of the wing skin. This work presents the first biaxial characterization of the local deformation, mechanical properties, and fiber kinematics of bat wing skin. Analysis of these data has provided insight into the relationships among the structural morphology, mechanical properties, and functionality of wing skin. Large spatial variations in tissue deformation and non-negligible fiber strains in the cross-fiber direction for both chordwise and spanwise fibers indicate fibers should be modeled as two-dimensional elements. The macroscopic constitutive behavior was anisotropic and nonlinear, with very low spanwise and chordwise stiffness (hundreds of kilopascals) in the toe region of the stress-strain curve. The structural arrangement of the fibers and matrix facilitates a low energy mechanism for wing deployment and extension, and we fabricate examples of skins capturing this mechanism. We propose a comprehensive deformation map for the entire loading regime. The results of this work underscore the importance of biaxial field approaches for soft heterogeneous tissue, and provide a foundation for development of bio-inspired skins to probe the effects of the wing skin properties on aerodynamic performance. PMID:25895436

  15. Numerical investigation of insect wing fracture behaviour.

    PubMed

    Rajabi, H; Darvizeh, A; Shafiei, A; Taylor, D; Dirks, J-H

    2015-01-01

    The wings of insects are extremely light-weight biological composites with exceptional biomechanical properties. In the recent years, numerical simulations have become a very powerful tool to answer experimentally inaccessible questions on the biomechanics of insect flight. However, many of the presented models require a sophisticated balance of biomechanical material parameters, many of which are not yet available. In this article we show the first numerical simulations of crack propagation in insect wings. We have used a combination of the maximum-principal stress theory, the traction separation law and basic biomechanical properties of cuticle to develop simple yet accurate finite element (FE) models of locust wings. The numerical results of simulated tensile tests on wing samples are in very good qualitative, and interestingly, also in excellent quantitative agreement with previously obtained experimental data. Our study further supports the idea that the cross-veins in insect wings act as barriers against crack propagation and consequently play a dominant role in toughening the whole wing structure. The use of numerical simulations also allowed us to combine experimental data with previously inaccessible data, such as the distribution of the first principal stress through the wing membrane and the veins. A closer look at the stress-distribution within the wings might help to better understand fracture-toughening mechanisms and also to design more durable biomimetic micro-air vehicles. PMID:25468669

  16. High speed flow past wings

    NASA Technical Reports Server (NTRS)

    Norstrud, H.

    1973-01-01

    The analytical solution to the transonic small perturbation equation which describes steady compressible flow past finite wings at subsonic speeds can be expressed as a nonlinear integral equation with the perturbation velocity potential as the unknown function. This known formulation is substituted by a system of nonlinear algebraic equations to which various methods are applicable for its solution. Due to the presence of mathematical discontinuities in the flow solutions, however, a main computational difficulty was to ensure uniqueness of the solutions when local velocities on the wing exceeded the speed of sound. For continuous solutions this was achieved by embedding the algebraic system in an one-parameter operator homotopy in order to apply the method of parametric differentiation. The solution to the initial system of equations appears then as a solution to a Cauchy problem where the initial condition is related to the accompanying incompressible flow solution. In using this technique, however, a continuous dependence of the solution development on the initial data is lost when the solution reaches the minimum bifurcation point. A steepest descent iteration technique was therefore, added to the computational scheme for the calculation of discontinuous flow solutions. Results for purely subsonic flows and supersonic flows with and without compression shocks are given and compared with other available theoretical solutions.

  17. Swept wing ice accretion modeling

    NASA Technical Reports Server (NTRS)

    Potapczuk, Mark G.; Bidwell, Colin S.

    1990-01-01

    An effort to develop a three-dimensional modeling method was initiated. This first step towards creation of a complete aircraft icing simulation code builds on previously developed methods for calculating three-dimensional flow fields and particle trajectories combined with a two-dimensional ice accretion calculation along coordinate locations corresponding to streamlines. This work is a demonstration of the types of calculations necessary to predict a three-dimensional ice accretion. Results of calculations using the 3-D method for a MS-317 swept wing geometry are projected onto a 2-D plane normal to the wing leading edge and compared to 2-D results for the same geometry. It is anticipated that many modifications will be made to this approach, however, this effort will lay the groundwork for future modeling efforts. Results indicate that the flow field over the surface and the particle trajectories differed for the two calculations. This led to lower collection efficiencies, convective heat transfer coefficients, freezing fractions, and ultimately ice accumulation for the 3-D calculation.

  18. Analysis of streamwise-oriented vortex interactions for two wings in close proximity

    NASA Astrophysics Data System (ADS)

    Barnes, Caleb J.; Visbal, Miguel R.; Gordnier, Raymond E.

    2015-01-01

    This investigation addresses the impingement of the trailing vortex provided by a leader-wing upon a follower-wing operating in close proximity. Exploration of the relative spacing between the two wings reveals several distinct flow regimes occur within a small range of lateral positions of the incident vortex. These changes effectively alter the evolution of the follower-wing wake via mutual induction between the incident and trailing vortices. Several unsteady mechanisms impact the general flow field in each regime. The incident vortex for an inboard impingement rapidly decays over the wing due to transition to turbulence. A tip-aligned vortex results in a highly unsteady interaction and generates enhanced surface pressure fluctuations beneath the tip vortex. Placing the incident vortex outboard elicits mutual instability between the leader and follower-wing trailing vortices. While lift-enhancement was found to be dominated by an inviscid increase in effective angle of attack, viscous effects in the near-tip region alter the local surface force distribution and influence the rolling moment coefficient. These flow variations which occur over a small range of lateral positions could generate buffeting loads in the presence of a wandering streamwise vortex.

  19. A fringe shadow method for measuring flapping angle and torsional angle of a dragonfly wing

    NASA Astrophysics Data System (ADS)

    Zeng, Lijiang; Matsumoto, Hirokazu; Kawachi, Keiji

    1996-05-01

    A fringe shadow (FS) method was developed for measuring the flapping angle and torsional angle of a dragonfly wing during beating motion. This new method involves two sets of fringe patterns projected onto the wing from orthogonal directions. The torsional angle is determined using the length of the shadow of the wing chord that is cast by the two sets of fringe patterns. The flapping angle is determined using the shadowgraph of the wing projected by a laser. The advantages of the FS method are its capability (i) to measure the flapping angle and torsional angle of a dragonfly wing simultaneously using only one high-speed camera and (ii) to recognize the spanwise position of a section from the number of fringes, without having to use diffuse marks that are common in current methods. The resolution of the FS method can be changed easily by adjusting the fringe spacing. The measurement results for the torsional angle and flapping angle of a dragonfly wing prove the effectiveness of the FS method in studying the flight performance of dragonflies.

  20. Calculation of the longitudinal aerodynamic characteristics of upper-surface-blown wing-flap configurations

    NASA Technical Reports Server (NTRS)

    Mendenhall, M. R.; Spangler, S. B.

    1978-01-01

    An engineering method for predicting the longitudinal aerodynamic characteristics of wing-flap configurations with upper surface blowing (USB) was developed. Potential flow models were incorporated into the prediction method: a wing and flap lifting surface model and a jet wake model. The wing-flap model used a vortex-lattice to represent the wing and flaps. The wing had an arbitrary planform and camber and twist, and the flap system was made up of a Coanda flap and other flap segments of arbitrary size. The jet wake model consisted of a series of closely spaced rectangular vortex rings. The wake was positioned such that it was tangent to the upper surface of the wing and flap between the exhaust nozzle and the flap trailing edge. It was specified such that the mass, momentum, and spreading rates were similar to actual USB jet wakes. Comparisons of measured and predicted pressure distributions, span load distributions, and total lift and pitching-moment coefficients on swept and unswept USB configurations are included. A wide range of thrust coefficients and flap deflection angles were considered at angles of attack up to the onset of stall.

  1. HYDRODYNAMIC MODELS OF RADIO GALAXY MORPHOLOGY: WINGED AND X-SHAPED SOURCES

    SciTech Connect

    Hodges-Kluck, Edmund J.; Reynolds, Christopher S.

    2011-05-20

    We present three-dimensional hydrodynamic models of radio galaxies interacting with initially relaxed hot atmospheres and explore the significant off-axis radio lobe structures that result under certain conditions. With a focus on the 'winged' and 'X-shaped' radio galaxy population, we confirm the importance of observed trends such as the connection of wing formation with jets co-aligned with the major axis of the surrounding atmosphere. These wings are formed substantially by the deflection of lobe plasma flowing back from the hot spots (backflow) and develop in two stages: supersonic expansion of an overpressured cocoon at early times followed by buoyant expansion at later times. We explore a limited parameter space of jet and atmosphere properties and find that the most prominent wings are produced when a decaying jet is injected into a small, dense, highly elliptical atmosphere. On the basis of this search, we argue that the deflection of backflow by gradients in the hot atmosphere is a strong candidate for forming observed wings but must work in tandem with some other mechanism for forming the initial wing channels. Our models indicate that lobe interaction with the hot atmosphere may play a dominant role in shaping the morphology of radio galaxies.

  2. Collective Flow Enhancement by Tandem Flapping Wings.

    PubMed

    Gravish, Nick; Peters, Jacob M; Combes, Stacey A; Wood, Robert J

    2015-10-30

    We examine the fluid-mechanical interactions that occur between arrays of flapping wings when operating in close proximity at a moderate Reynolds number (Re≈100-1000). Pairs of flapping wings are oscillated sinusoidally at frequency f, amplitude θ_{M}, phase offset ϕ, and wing separation distance D^{*}, and outflow speed v^{*} is measured. At a fixed separation distance, v^{*} is sensitive to both f and ϕ, and we observe both constructive and destructive interference in airspeed. v^{*} is maximized at an optimum phase offset, ϕ_{max}, which varies with wing separation distance, D^{*}. We propose a model of collective flow interactions between flapping wings based on vortex advection, which reproduces our experimental data. PMID:26565499

  3. Collective Flow Enhancement by Tandem Flapping Wings

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Peters, Jacob M.; Combes, Stacey A.; Wood, Robert J.

    2015-10-01

    We examine the fluid-mechanical interactions that occur between arrays of flapping wings when operating in close proximity at a moderate Reynolds number (Re ≈100 - 1000 ). Pairs of flapping wings are oscillated sinusoidally at frequency f , amplitude θM, phase offset ϕ , and wing separation distance D*, and outflow speed v* is measured. At a fixed separation distance, v* is sensitive to both f and ϕ , and we observe both constructive and destructive interference in airspeed. v* is maximized at an optimum phase offset, ϕmax, which varies with wing separation distance, D*. We propose a model of collective flow interactions between flapping wings based on vortex advection, which reproduces our experimental data.

  4. General theory of thin wing sections

    NASA Technical Reports Server (NTRS)

    Munk, Max M

    1923-01-01

    This report contains a new, simple method of calculating the air forces to which thin wings are subjected at small angles of attack, if their curvature is not too great. Two simple integrals are the result. They contain only the coordinates of the wing section. The first integral gives the angle of attack at which the lift of the wing is zero, the second integral gives the moment experienced by the wing when its angle is zero. The two constants thus obtained are sufficient to determine the lift and moment for any other angle of attack. This with the theory of the aerodynamical induction, and with our empirical knowledge of the drag due to friction, the results are valuable for actual wings also. A particular result obtained is the calculation of the elevator effect. (author)

  5. Design of a transonically profiled wing

    NASA Technical Reports Server (NTRS)

    Kiekebusch, B.

    1978-01-01

    The application of well known design concepts with the combined use of thick transonic profiles to aircraft wing design was investigated. Optimization in terms of weight and operational costs was emphasized. It is shown that the usual design criteria and concepts are too restricted and do not sufficiently represent the physical processes over the wing. Suggestions are made for improving this situation, and a design example given. Compared with a wing design according to previously used criteria, the new design is found to be superior in the most important functions. It is concluded that an isobar concept adjusted to the planform in conjunction with an 'organically' designed wing will lead to the weight optimum solutions of wing profiles.

  6. X-wing potential for Navy applications

    NASA Technical Reports Server (NTRS)

    Linden, Arthur W.; Biggers, James C.

    1987-01-01

    The X-wing provides a VTOL aircraft which has a low disc loading hover capability, similar to a conventional helicopter, combined with a high subsonic cruise speed capability. As a result, it hovers with low fuel flow rates which make extended hover duration missions practical. Its low hover power requirements also permit hovering and low speed flight on only one engine in a high speed twin engine aircraft design. The NASA DARPA Sikorsky RSRA X-wing program developed flightworthy X-wing hardware. All design activity and the majority of its component fabrication is completed. A design study was performed on an X-wing concept demonstrator aircraft which is based on the RSRA X-wing components, combined with two MTE engines and a new fuselage.

  7. Wing rock suppression using forebody vortex control

    NASA Technical Reports Server (NTRS)

    Ng, T. T.; Ong, L. Y.; Suarez, C. J.; Malcolm, G. N.

    1991-01-01

    Static and free-to-roll tests were conducted in a water tunnel with a configuration that consisted of a highly-slender forebody and 78-deg sweep delta wings. Flow visualization was performed and the roll angle histories were obtained. The fluid mechanisms governing the wing rock of this configuration were identified. Different means of suppressing wing rock by controlling the forebody vortices using small blowing jets were also explored. Steady blowing was found to be capable of suppressing wing rock, but significant vortex asymmetries had to be induced at the same time. On the other hand, alternating pulsed blowing on the left and right sides of the forebody was demonstrated to be potentially an effective means of suppressing wing rock and eliminating large asymmetric moments at high angles of attack.

  8. Pegasus Rocket Wing and PHYSX Glove Undergoes Stress Loads Testing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Pegasus Hypersonic Experiment (PHYSX) Project's Pegasus rocket wing with attached PHYSX glove rests after load-tests at Scaled Composites, Inc., in Mojave, California, in January 1997. Technicians slowly filled water bags beneath the wing, to create the pressure, or 'wing-loading,' required to determine whether the wing could withstand its design limit for stress. The wing sits in a wooden triangular frame which serves as the test-rig, mounted to the floor atop the waterbags. Pegasus is an air-launched space booster produced by Orbital Sciences Corporation and Hercules Aerospace Company (initially; later, Alliant Tech Systems) to provide small satellite users with a cost-effective, flexible, and reliable method for placing payloads into low earth orbit. Pegasus has been used to launch a number of satellites and the PHYSX experiment. That experiment consisted of a smooth glove installed on the first-stage delta wing of the Pegasus. The glove was used to gather data at speeds of up to Mach 8 and at altitudes approaching 200,000 feet. The flight took place on October 22, 1998. The PHYSX experiment focused on determining where boundary-layer transition occurs on the glove and on identifying the flow mechanism causing transition over the glove. Data from this flight-research effort included temperature, heat transfer, pressure measurements, airflow, and trajectory reconstruction. Hypersonic flight-research programs are an approach to validate design methods for hypersonic vehicles (those that fly more than five times the speed of sound, or Mach 5). Dryden Flight Research Center, Edwards, California, provided overall management of the glove experiment, glove design, and buildup. Dryden also was responsible for conducting the flight tests. Langley Research Center, Hampton, Virginia, was responsible for the design of the aerodynamic glove as well as development of sensor and instrumentation systems for the glove. Other participating NASA centers included Ames Research

  9. Advanced turboprop wing installation effects measured by unsteady blade pressure and noise

    NASA Technical Reports Server (NTRS)

    Heidelberg, Laurence J.; Woodward, Richard P.

    1987-01-01

    A single rotation model propeller (SR-7A) was tested at simulated takeoff/approach conditions (Mach 0.2), in the NASA Lewis 9- by 15-Ft Anechoic Wind Tunnel. Both unsteady blade surface pressures and noise measurements were made for a tractor configuration with propeller/straight wing and propeller alone configurations. The angle between the wing chord and propeller axis (droop angle) was varied along with the wing angle of attack to determine the effects on noise and unsteady loading. A method was developed that uses unsteady blade pressure measurements to provide a quantitative indication of propeller inflow conditions, at least for a uniform (across the propeller disk) inflow angle. The wing installation caused a nearly uniform upwash at the propeller inlet as evidenced by the domination of the pressure spectra by the first shaft order. This inflow angle increased at a rate of almost 150 percent of that of the wing angle-of-attack for a propeller-wing spacing of 0.54 wing chords at a constant droop angle. The flyover noise, as measured by the maximum blade passing frequency level, correlates closely with the propeller inflow angle (approx. 0.6 dB per degree of inflow angle) for all droop angles and wing angles of attack tested, including the propeller alone data. Large changes in the unsteady pressure responses on the suction surface of the blade were observed as the advance ratio was varied. The presence of a leading edge vortex may explain this behavior since changes in the location of this vortex would change with loading (advance ratio).

  10. Commercial winged booster to launch satellites from B-52

    NASA Astrophysics Data System (ADS)

    Covault, Craig

    1988-06-01

    A newly developed commercial winged space booster, the Pegasus, which will launch satellites from a B-52, is described. The booster will be able to launch a 600 lb, 72 in long craft into a 250 nm equatorial orbit. The Pegasus is 49.2 ft long with a 22 ft wing span and a weight of 40,000 lb. The winged design allows for an angle of attack of 20 degrees and a supersonic lift over drag ratio of 4:1. It operates with three solid rocket motors and will be launched from a B-52 at an altitude of 40,000 ft. The first motor provides an average of 112,000 lbs of thrust for about 82 seconds; burnout occurs at 208,000 ft and Mach 8.7. The third stage provides 9,000 lbs of thrust for 65 seconds, accelerating the vehicle into 25,000 fps orbital velocity. The first launch will be a 400 lb relay satellite targeted for July 1989 over the Pacific Ocean. Future launches will be possible from any site and will cost 10 million dollars. The Pegasus can also carry a 1500 payload at high altitude Mach cruise flights that do not achieve orbit, providing data to validate spaceplane conceptual fluid dynamic codes generated by computer.

  11. Integrated Model Reduction and Control of Aircraft with Flexible Wings

    NASA Technical Reports Server (NTRS)

    Swei, Sean Shan-Min; Zhu, Guoming G.; Nguyen, Nhan T.

    2013-01-01

    This paper presents an integrated approach to the modeling and control of aircraft with exible wings. The coupled aircraft rigid body dynamics with a high-order elastic wing model can be represented in a nite dimensional state-space form. Given a set of desired output covariance, a model reduction process is performed by using the weighted Modal Cost Analysis (MCA). A dynamic output feedback controller, which is designed based on the reduced-order model, is developed by utilizing output covariance constraint (OCC) algorithm, and the resulting OCC design weighting matrix is used for the next iteration of the weighted cost analysis. This controller is then validated for full-order evaluation model to ensure that the aircraft's handling qualities are met and the uttering motion of the wings suppressed. An iterative algorithm is developed in CONDUIT environment to realize the integration of model reduction and controller design. The proposed integrated approach is applied to NASA Generic Transport Model (GTM) for demonstration.

  12. Effects of the air breathing engine plumes on SSV orbiter subsonic wing pressure distributions (OA57A)

    NASA Technical Reports Server (NTRS)

    Cameron, B. W., Jr.

    1974-01-01

    Experimental aerodynamic pressure investigations were conducted on a 0.0405 scale representation of the -89 space shuttle orbiter ferry configuration in the Rockwell International 7.75 x 11.00 foot Low Speed Wind Tunnel. The primary test objective was to investigate the orbiter wing pressure distribution resulting from five under-wing engine nacelle plumes. Two five engine nacelle configurations were tested at 3 ground plane heights with pressure bug measurements being made on the left upper and lower wing panel. In addition, base and balance cavity pressure measurements were made, with elevon normal and hinge moment measurements on the right panel.

  13. Optical properties of chitin: surface-enhanced Raman scattering substrates based on antireflection structures on cicada wings

    NASA Astrophysics Data System (ADS)

    Stoddart, P. R.; Cadusch, P. J.; Boyce, T. M.; Erasmus, R. M.; Comins, J. D.

    2006-02-01

    The transparent wings of some cicada species present ordered arrays of papillary structures with a spacing of approximately 200 nm. These structures serve an antireflection function, with optical transmission peaking at a value of approximately 98% and rising above 90% over a broad band from 450 to 2500 nm. The dimensions of the papillae are comparable to the roughness scale of surface-enhanced Raman scattering (SERS) substrates. SERS measurements performed on silver- and gold-coated wings display enhancement factors of approximately 106 with no apparent background contribution from the wing.

  14. Global optimization of actively morphing flapping wings

    NASA Astrophysics Data System (ADS)

    Ghommem, Mehdi; Hajj, Muhammad R.; Mook, Dean T.; Stanford, Bret K.; Beran, Philip S.; Snyder, Richard D.; Watson, Layne T.

    2012-08-01

    We consider active shape morphing to optimize the flight performance of flapping wings. To this end, we combine a three-dimensional version of the unsteady vortex lattice method (UVLM) with a deterministic global optimization algorithm to identify the optimal kinematics that maximize the propulsive efficiency under lift and thrust constraints. The UVLM applies only to incompressible, inviscid flows where the separation lines are known a priori. Two types of morphing parameterization are investigated here—trigonometric and spline-based. The results show that the spline-based morphing, which requires specification of more design variables, yields a significant improvement in terms of propulsive efficiency. Furthermore, we remark that the average value of the lift coefficient in the optimized kinematics remained equal to the value in the baseline case (without morphing). This indicates that morphing is most efficiently used to generate thrust and not to increase lift beyond the basic value obtained by flapping only. Besides, our study gives comparable optimal efficiencies to those obtained from previous studies based on gradient-based optimization, but completely different design points (especially for the spline-based morphing), which would indicate that the design space associated with the flapping kinematics is very complex.

  15. Followup to Columbia Investigation: Reinforced Carbon/Carbon From the Breach Location in the Wing Leading Edge Studied

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.; Opila, Elizabeth J.; Tallant, David

    2005-01-01

    Initial estimates on the temperature and conditions of the breach in the Space Shuttle Columbia's wing focused on analyses of the slag deposits. These deposits are complex mixtures of the reinforced carbon/carbon (RCC) constituents, insulation material, and wing structural materials. Identification of melted/solidified Cerachrome insulation (Thermal Ceramics, Inc., Augusta, GA) indicated that the temperatures at the breach had exceeded 1760 C.

  16. Gain-Scheduled Approximations to H-Infinity Controllers for the F/A-18 Active Aeroelastic Wing

    NASA Technical Reports Server (NTRS)

    Lind, Rick

    1999-01-01

    The Active Aeroelastic Wing will demonstrate technologies related to aeroservoelastic effects such as wing twist and load minimization. This paper presents a control design based on H-infinity synthesis that simultaneously considers the multiple objectives associated with handling qualities, actuator limitations, and loads. The controller is realized as a filter and gain set approximation to a state-space H-infinity controller. This approximation allows scheduling of the controller over a flight envelope.

  17. Design, fabrication, and characterization of multifunctional wings to harvest solar energy in flapping wing air vehicles

    NASA Astrophysics Data System (ADS)

    Perez-Rosado, Ariel; Gehlhar, Rachel D.; Nolen, Savannah; Gupta, Satyandra K.; Bruck, Hugh A.

    2015-06-01

    Currently, flapping wing unmanned aerial vehicles (a.k.a., ornithopters or robotic birds) sustain very short duration flight due to limited on-board energy storage capacity. Therefore, energy harvesting elements, such as flexible solar cells, need to be used as materials in critical components, such as wing structures, to increase operational performance. In this paper, we describe a layered fabrication method that was developed for realizing multifunctional composite wings for a unique robotic bird we developed, known as Robo Raven, by creating compliant wing structure from flexible solar cells. The deformed wing shape and aerodynamic lift/thrust loads were characterized throughout the flapping cycle to understand wing mechanics. A multifunctional performance analysis was developed to understand how integration of solar cells into the wings influences flight performance under two different operating conditions: (1) directly powering wings to increase operation time, and (2) recharging batteries to eliminate need for external charging sources. The experimental data is then used in the analysis to identify a performance index for assessing benefits of multifunctional compliant wing structures. The resulting platform, Robo Raven III, was the first demonstration of a robotic bird that flew using energy harvested from solar cells. We developed three different versions of the wing design to validate the multifunctional performance analysis. It was also determined that residual thrust correlated to shear deformation of the wing induced by torsional twist, while biaxial strain related to change in aerodynamic shape correlated to lift. It was also found that shear deformation of the solar cells induced changes in power output directly correlating to thrust generation associated with torsional deformation. Thus, it was determined that multifunctional solar cell wings may be capable of three functions: (1) lightweight and flexible structure to generate aerodynamic forces, (2

  18. Minutes of the 30th Delegate Assembly.

    ERIC Educational Resources Information Center

    Cieslak, Bert

    1987-01-01

    Summarizes the topics covered in the resolutions passed by the House of Delegates including academic freedom, racial and ethnic content of instructional materials, research in social studies, early childhood/elementary social studies, instruction regarding religious freedom, apartheid, and astronaut Christa McAuliffe. (JDH)

  19. Aerodynamics of high frequency flapping wings

    NASA Astrophysics Data System (ADS)

    Hu, Zheng; Roll, Jesse; Cheng, Bo; Deng, Xinyan

    2010-11-01

    We investigated the aerodynamic performance of high frequency flapping wings using a 2.5 gram robotic insect mechanism developed in our lab. The mechanism flaps up to 65Hz with a pair of man-made wing mounted with 10cm wingtip-to-wingtip span. The mean aerodynamic lift force was measured by a lever platform, and the flow velocity and vorticity were measured using a stereo DPIV system in the frontal, parasagittal, and horizontal planes. Both near field (leading edge vortex) and far field flow (induced flow) were measured with instantaneous and phase-averaged results. Systematic experiments were performed on the man-made wings, cicada and hawk moth wings due to their similar size, frequency and Reynolds number. For insect wings, we used both dry and freshly-cut wings. The aerodynamic force increase with flapping frequency and the man-made wing generates more than 4 grams of lift at 35Hz with 3 volt input. Here we present the experimental results and the major differences in their aerodynamic performances.

  20. Insect Wing Displacement Measurement Using Digital Holography

    SciTech Connect

    Aguayo, Daniel D.; Mendoza Santoyo, Fernando; Torre I, Manuel H. de la; Caloca Mendez, Cristian I.

    2008-04-15

    Insects in flight have been studied with optical non destructive techniques with the purpose of using meaningful results in aerodynamics. With the availability of high resolution and large dynamic range CCD sensors the so called interferometric digital holographic technique was used to measure the surface displacement of in flight insect wings, such as butterflies. The wings were illuminated with a continuous wave Verdi laser at 532 nm, and observed with a CCD Pixelfly camera that acquire images at a rate of 11.5 frames per second at a resolution of 1392x1024 pixels and 12 Bit dynamic range. At this frame rate digital holograms of the wings were captured and processed in the usual manner, namely, each individual hologram is Fourier processed in order to find the amplitude and phase corresponding to the digital hologram. The wings displacement is obtained when subtraction between two digital holograms is performed for two different wings position, a feature applied to all consecutive frames recorded. The result of subtracting is seen as a wrapped phase fringe pattern directly related to the wing displacement. The experimental data for different butterfly flying conditions and exposure times are shown as wire mesh plots in a movie of the wings displacement.

  1. Periodic and chaotic flapping of insectile wings

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Kanso, E.

    2015-11-01

    Insects use flight muscles attached at the base of the wings to produce impressive wing flapping frequencies. The maximum power output of these flight muscles is insufficient to maintain such wing oscillations unless there is good elastic storage of energy in the insect flight system. Here, we explore the intrinsic self-oscillatory behavior of an insectile wing model, consisting of two rigid wings connected at their base by an elastic torsional spring. We study the wings behavior as a function of the total energy and spring stiffness. Three types of behavior are identified: end-over-end rotation, chaotic motion, and periodic flapping. Interestingly, the region of periodic flapping decreases as energy increases but is favored as stiffness increases. These findings are consistent with the fact that insect wings and flight muscles are stiff. They further imply that, by adjusting their muscle stiffness to the energy level at which they are operating, insects can maintain periodic flapping mechanically for a range of operating conditions.

  2. Nanostructured Antireflective and Thermoisolative Cicada Wings.

    PubMed

    Morikawa, Junko; Ryu, Meguya; Seniutinas, Gediminas; Balčytis, Armandas; Maximova, Ksenia; Wang, Xuewen; Zamengo, Massimiliano; Ivanova, Elena P; Juodkazis, Saulius

    2016-05-10

    Inter-related mechanical, thermal, and optical macroscopic properties of biomaterials are defined at the nanoscale by their constituent structures and patterns, which underpin complex functions of an entire bio-object. Here, the temperature diffusivity of a cicada (Cyclochila australasiae) wing with nanotextured surfaces was measured using two complementary techniques: a direct contact method and IR imaging. The 4-6-μm-thick wing section was shown to have a thermal diffusivity of α⊥ = (0.71 ± 0.15) × 10(-7) m(2)/s, as measured by the contact temperature wave method along the thickness of the wing; it corresponds to the inherent thermal property of the cuticle. The in-plane thermal diffusivity value of the wing was determined by IR imaging and was considerably larger at α∥ = (3.6 ± 0.2) × 10(-7) m(2)/s as a result of heat transport via air. Optical properties of wings covered with nanospikes were numerically simulated using an accurate 3D model of the wing pattern and showed that light is concentrated between spikes where intensity is enhanced by up to 3- to 4-fold. The closely packed pattern of nanospikes reduces the reflectivity of the wing throughout the visible light spectrum and over a wide range of incident angles, hence acting as an antireflection coating. PMID:27101865

  3. Delta wing flutter based on doublet lattice method in NASTRAN

    NASA Technical Reports Server (NTRS)

    Jew, H.

    1975-01-01

    The subsonic doublet-lattice method (DLM) aeroelastic analysis in NASTRAN was successfully applied to produce subsonic flutter boundary data in parameter space for a large delta wing configuration. Computed flow velocity and flutter frequency values as functions of air density ratio, flow Mach number, and reduced frequency are tabulated. The relevance and the meaning of the calculated results are discussed. Several input-deck problems encountered and overcome are cited with the hope that they may be helpful to NASTRAN Rigid Format 45 users.

  4. Integrated technology wing design study

    NASA Technical Reports Server (NTRS)

    Hays, A. P.; Beck, W. E.; Morita, W. H.; Penrose, B. J.; Skarshaug, R. E.; Wainfan, B. S.

    1984-01-01

    The technology development costs and associated benefits in applying advanced technology associated with the design of a new wing for a new or derivative trijet with a capacity for 350 passengers and maximum range of 8519 km, entering service in 1990 were studied. The areas of technology are: (1) airfoil technology; (2) planform parameters; (3) high lift; (4) pitch active control system; (5) all electric systems; (6) E to 3rd power propulsion; (7) airframe/propulsion integration; (8) graphite/epoxy composites; (9) advanced aluminum alloys; (10) titanium alloys; and (11) silicon carbide/aluminum composites. These technologies were applied to the reference aircraft configuration. Payoffs were determined for block fuel reductions and net value of technology. These technologies are ranked for the ratio of net value of technology (NVT) to technology development costs.

  5. Novel Control Effectors for Truss Braced Wing

    NASA Technical Reports Server (NTRS)

    White, Edward V.; Kapania, Rakesh K.; Joshi, Shiv

    2015-01-01

    At cruise flight conditions very high aspect ratio/low sweep truss braced wings (TBW) may be subject to design requirements that distinguish them from more highly swept cantilevered wings. High aspect ratio, short chord length and relative thinness of the airfoil sections all contribute to relatively low wing torsional stiffness. This may lead to aeroelastic issues such as aileron reversal and low flutter margins. In order to counteract these issues, high aspect ratio/low sweep wings may need to carry additional high speed control effectors to operate when outboard ailerons are in reversal and/or must carry additional structural weight to enhance torsional stiffness. The novel control effector evaluated in this study is a variable sweep raked wing tip with an aileron control surface. Forward sweep of the tip allows the aileron to align closely with the torsional axis of the wing and operate in a conventional fashion. Aft sweep of the tip creates a large moment arm from the aileron to the wing torsional axis greatly enhancing aileron reversal. The novelty comes from using this enhanced and controllable aileron reversal effect to provide roll control authority by acting as a servo tab and providing roll control through intentional twist of the wing. In this case the reduced torsional stiffness of the wing becomes an advantage to be exploited. The study results show that the novel control effector concept does provide roll control as described, but only for a restricted class of TBW aircraft configurations. For the configuration studied (long range, dual aisle, Mach 0.85 cruise) the novel control effector provides significant benefits including up to 12% reduction in fuel burn.

  6. MTR WING A, TRA604. SOUTH SIDE. CAMERA FACING NORTH. THIS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR WING A, TRA-604. SOUTH SIDE. CAMERA FACING NORTH. THIS VIEW TYPIFIES TENDENCY FOR EXPANSIONS TO TAKE THE FORM OF PROJECTIONS AND INFILL USING AVAILABLE YARD SPACES. INL NEGATIVE NO. HD47-44-3. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  7. The plane problem of the flapping wing

    NASA Technical Reports Server (NTRS)

    Birnbaum, Walter

    1954-01-01

    In connection with an earlier report on the lifting vortex sheet which forms the basis of the following investigations this will show how the methods developed there are also suitable for dealing with the air forces for a wing with a circulation variable with time. The theory of a propulsive wing flapping up and down periodically in the manner of a bird's wing is developed. This study shows how the lift and its moment result as a function of the flapping motion, what thrust is attainable, and how high is the degree of efficiency of this flapping propulsion unit if the air friction is disregarded.

  8. Moveable Leading Edge Device for a Wing

    NASA Technical Reports Server (NTRS)

    Pitt, Dale M. (Inventor); Eckstein, Nicholas Stephen (Inventor)

    2013-01-01

    A method and apparatus for managing a flight control surface system. A leading edge section on a wing of an aircraft is extended into a deployed position. A deformable section connects the leading edge section to a trailing section. The deformable section changes from a deformed shape to an original shape when the leading edge section is moved into the deployed position. The leading edge section on the wing is moved from the deployed position to an undeployed position. The deformable section changes to the deformed shape inside of the wing.

  9. A Miniature Controllable Flapping Wing Robot

    NASA Astrophysics Data System (ADS)

    Arabagi, Veaceslav Gheorghe

    The agility and miniature size of nature's flapping wing fliers has long baffled researchers, inspiring biological studies, aerodynamic simulations, and attempts to engineer their robotic replicas. Flapping wing flight is characterized by complex reciprocating wing kinematics, transient aerodynamic effects, and very small body lengths. These characteristics render robotic flapping wing aerial vehicles ideal for surveillance and defense applications, search and rescue missions, and environment monitoring, where their ability to hover and high maneuverability is immensely beneficial. One of the many difficulties in creating flapping wing based miniature robotic aerial vehicles lies in generating a proper wing trajectory that would result in sufficient lift forces for hovering and maneuvering. Since design of a flapping wing system is a balance between overall weight and the number of actuated inputs, we take the approach of having minimal controlled inputs, allowing passive behavior wherever possible. Hence, we propose a completely passive wing pitch reversal design that relies on wing inertial dynamics, an elastic energy storage mechanism, and low Reynolds number aerodynamic effects. Theoretical models, compiling previous research on piezoelectric actuators, four-bar transmissions, and aerodynamics effects, are developed and used as basis for a complete numerical simulation. Limitations of the model are discussed in comparison to experimental results obtained from a working prototype of the proposed passive pitch reversal flapping wing mechanism. Given that the mechanism is under-actuated, methods to control lift force generation by actively varying system parameters are proposed, discussed, and tested experimentally. A dual wing aerial platform is developed based on the passive pitch reversal wing concept. Design considerations are presented, favoring controllability and structural rigidity of the final platform. Finite element analysis and experimental

  10. Surface photometry of WINGS galaxies with GASPHOT

    NASA Astrophysics Data System (ADS)

    D'Onofrio, M.; Bindoni, D.; Fasano, G.; Bettoni, D.; Cava, A.; Fritz, J.; Gullieuszik, M.; Kjærgaard, P.; Moretti, A.; Moles, M.; Omizzolo, A.; Poggianti, B. M.; Valentinuzzi, T.; Varela, J.

    2014-12-01

    Aims: We present the B, V, and K band surface photometry catalogs obtained by running the automatic software GASPHOT on galaxies from the WINGS cluster survey with isophotal areas larger than 200 pixels. The catalogs can be downloaded at the Centre de Données Astronomiques de Strasbourg. Methods: The luminosity growth curves of stars and galaxies in a given catalog relative to a given cluster image were obtained simultaneously by slicing the image with a fixed surface brightness step in several SExtractor runs. Then, using a single Sersic law convolved with a space-varying point spread function (PSF), GASPHOT performed a simultaneous χ2 best-fit of the major- and minor-axis luminosity growth curves of galaxies. We outline the GASPHOT performances and compare our surface photometry with that obtained by SExtractor, GALFIT, and GIM2D. This analysis is aimed at providing statistical information about the accuracy that is generally achieved by the softwares for automatic surface photometry of galaxies. Results: The GASPHOT catalogs provide the parameters of the Sersic law that fit the luminosity profiles for each galaxy and for each photometric band. They are the sky coordinates of the galaxy center (RA, Dec), the total magnitude (m), the semi-major axis of the effective isophote (Re), the Sersic index (n), the axis ratio (b/a), and a flag parameter (QFLAG) that generally indicates the fit quality. The WINGS-GASPHOT database includes 41 463 galaxies in the B band, 42 275 in the V band, and 71 687 in the K band. The bright early-type galaxies have higher Sersic indices and larger effective radii, as well as redder colors in their center. In general, the effective radii increase systematically from the K to the V and B band. Conclusions: The GASPHOT photometry agrees well with the surface photometry obtained by GALFIT and GIM2D, and with the aperture photometry provided by SExtractor. In particular, the direct comparison of structural parameters derived by different

  11. The effect of asymmetric vortex wake characteristics on a slender delta wing undergoing wing rock motion

    NASA Technical Reports Server (NTRS)

    Arena, A. S., Jr.; Nelson, R. C.

    1989-01-01

    An experimental investigation into the fluid mechanisms responsible for wing rock on a slender delta wing with 80 deg leading edge sweep has been conducted. Time history and flow visualization data are presented for a wide angle-of-attack range. The use of an air bearing spindle has allowed the motion of the wing to be free from bearing friction or mechanical hysteresis. A bistable static condition has been found in vortex breakdown at an angle of attack of 40 deg which causes an overshoot of the steady state rocking amplitude. Flow visualization experiments also reveal a difference in static and dynamic breakdown locations on the wing. A hysteresis loop in dynamic breakdown location similar to that seen on pitching delta wings was observed as the wing was undergoing the limit cycle oscillation.

  12. Aerodynamic shape optimization of wing and wing-body configurations using control theory

    NASA Technical Reports Server (NTRS)

    Reuther, James; Jameson, Antony

    1995-01-01

    This paper describes the implementation of optimization techniques based on control theory for wing and wing-body design. In previous studies it was shown that control theory could be used to devise an effective optimization procedure for airfoils and wings in which the shape and the surrounding body-fitted mesh are both generated analytically, and the control is the mapping function. Recently, the method has been implemented for both potential flows and flows governed by the Euler equations using an alternative formulation which employs numerically generated grids, so that it can more easily be extended to treat general configurations. Here results are presented both for the optimization of a swept wing using an analytic mapping, and for the optimization of wing and wing-body configurations using a general mesh.

  13. The effect of over-the-wing nacelles on wing-body aerodynamics

    NASA Technical Reports Server (NTRS)

    Reubush, D. E.

    1978-01-01

    An investigation was conducted in the Langley 16-foot transonic tunnel to further study benefits in climb and cruise performance due to blowing the jet over the wing for a transport-type wing-body configuration. In this investigation a wing-body model/powered-nacelle test rig combination was tested at Mach numbers of 0.5 and 0.8 at angles of attack from -2 to 4 deg and jet total-pressure ratios from jet off to 3 or 4 (depending on Mach number) for a variety of nacelle locations relative to the wing. Results from this investigation show that positioning of the nacelles can have very large effects on the wing-body drag (nacelles were nonmetric). Some positions yielded much higher drag than the baseline wing-body while others yielded drag which was somewhat lower than the baseline.

  14. Prebiotic chemistry in space; Proceedings of Symposia B1.4 and F3.3 of the COSPAR Scientific Assembly, 30th, Hamburg, Germany, July 11-21, 1994

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A two-part symposium was held concerning topics in Solar System chemistry. The first part covered the organic chemistry ofsmall bodies of the interplanetray medium. It produced papers on the evolution, spectral properties and composition of organic matter in comets, interplanetary dust and asteroids. The second part covered cryochemistry and exobiology in planetary atmospheres (gas giant planets and their satellites) and in various astronomical ices.

  15. Thin tailored composite wing for civil tiltrotor

    NASA Technical Reports Server (NTRS)

    Rais-Rohani, Masoud

    1994-01-01

    The tiltrotor aircraft is a flight vehicle which combines the efficient low speed (i.e., take-off, landing, and hover) characteristics of a helicopter with the efficient cruise speed of a turboprop airplane. A well-known example of such vehicle is the Bell-Boeing V-22 Osprey. The high cruise speed and range constraints placed on the civil tiltrotor require a relatively thin wing to increase the drag-divergence Mach number which translates into lower compressibility drag. It is required to reduce the wing maximum thickness-to-chord ratio t/c from 23% (i.e., V-22 wing) to 18%. While a reduction in wing thickness results in improved aerodynamic efficiency, it has an adverse effect on the wing structure and it tends to reduce structural stiffness. If ignored, the reduction in wing stiffness leads to susceptibility to aeroelastic and dynamic instabilities which may consequently cause a catastrophic failure. By taking advantage of the directional stiffness characteristics of composite materials the wing structure may be tailored to have the necessary stiffness, at a lower thickness, while keeping the weight low. The goal of this study is to design a wing structure for minimum weight subject to structural, dynamic and aeroelastic constraints. The structural constraints are in terms of strength and buckling allowables. The dynamic constraints are in terms of wing natural frequencies in vertical and horizontal bending and torsion. The aeroelastic constraints are in terms of frequency placement of the wing structure relative to those of the rotor system. The wing-rotor-pylon aeroelastic and dynamic interactions are limited in this design study by holding the cruise speed, rotor-pylon system, and wing geometric attributes fixed. To assure that the wing-rotor stability margins are maintained a more rigorous analysis based on a detailed model of the rotor system will need to ensue following the design study. The skin-stringer-rib type architecture is used for the wing

  16. Active Dihedral Control System for a Torisionally Flexible Wing

    NASA Technical Reports Server (NTRS)

    Kendall, Greg T. (Inventor); Lisoski, Derek L. (Inventor); Morgan, Walter R. (Inventor); Griecci, John A. (Inventor)

    2015-01-01

    A span-loaded, highly flexible flying wing, having horizontal control surfaces mounted aft of the wing on extended beams to form local pitch-control devices. Each of five spanwise wing segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other wing segments, to minimize inter-segment loads. Wing dihedral is controlled by separately controlling the local pitch-control devices consisting of a control surface on a boom, such that inboard and outboard wing segment pitch changes relative to each other, and thus relative inboard and outboard lift is varied.

  17. Experimental and numerical analysis of the wing rock characteristics of a 'wing-body-tail' configuration

    NASA Technical Reports Server (NTRS)

    Suarez, Carlos J.; Smith, Brooke C.; Malcolm, Gerald N.

    1993-01-01

    Free-to-roll wind tunnel tests were conducted and a computer simulation exercise was performed in an effort to investigate in detail the mechanism of wing rock on a configuration that consisted of a highly-slender forebody and a 78 deg swept delta wing. In the wind tunnel test, the roll angle and wing surface pressures were measured during the wing rock motion. A limit cycle oscillation was observed for angles of attack between 22 deg and 30 deg. In general, the wind tunnel test confirmed that the main flow phenomena responsible for the wing-body-tail wing rock are the interactions between the forebody and the wing vortices. The variation of roll acceleration (determined from the second derivative of the roll angle time history) with roll angle clearly showed the energy balance necessary to sustain the limit cycle oscillation. Pressure measurements on the wing revealed the hysteresis of the wing rock process. First, second and nth order models for the aerodynamic damping were developed and examined with a one degree of freedom computer simulation. Very good agreement with the observed behavior from the wind tunnel was obtained.

  18. Wing loading on a 60 degree delta wing with vortex flaps

    NASA Technical Reports Server (NTRS)

    Marchman, J. F., III; Donatelli, D. A.; Terry, J. E.

    1983-01-01

    Wind tunnel tests were conducted on a 60 deg delta wing with three vortex flap designs to determine pressure distributions over the wing and flap. The results showed that an optimum vortex flap design depends on proper definition of the vortex flap deflection angle. They also revealed that flap thickness plays an important role in the behavior of the vortex flow over the flap and wing and can have a substantial effect on wing and flap pressure loading. Design codes which fail to account for thickness may result in a much less than optimum flap and deprive the designer of an important tool in designing an effective flap with optimum loading.

  19. Design for approaching Cicada-wing reflectance in low- and high-index biomimetic nanostructures.

    PubMed

    Huang, Yi-Fan; Jen, Yi-Jun; Chen, Li-Chyong; Chen, Kuei-Hsien; Chattopadhyay, Surojit

    2015-01-27

    Natural nanostructures in low refractive index Cicada wings demonstrate ≤ 1% reflectance over the visible spectrum. We provide design parameters for Cicada-wing-inspired nanotip arrays as efficient light harvesters over a 300-1000 nm spectrum and up to 60° angle of incidence in both low-index, such as silica and indium tin oxide, and high-index, such as silicon and germanium, photovoltaic materials. Biomimicry of the Cicada wing design, demonstrating gradient index, onto these material surfaces, either by real electron cyclotron resonance microwave plasma processing or by modeling, was carried out to achieve a target reflectance of ∼ 1%. Design parameters of spacing/wavelength and length/spacing fitted into a finite difference time domain model could simulate the experimental reflectance values observed in real silicon and germanium or in model silica and indium tin oxide nanotip arrays. A theoretical mapping of the length/spacing and spacing/wavelength space over varied refractive index materials predicts that lengths of ∼ 1.5 μm and spacings of ∼ 200 nm in high-index and lengths of ∼ 200-600 nm and spacings of ∼ 100-400 nm in low-index materials would exhibit ≤ 1% target reflectance and ∼ 99% optical absorption over the entire UV-vis region and angle of incidence up to 60°. PMID:25555063

  20. On the Minimum Induced Drag of Wings

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.

    2007-01-01

    This viewgraph presentation reviews the minimum induced drag of wings. The topics include: 1) The History of Spanload Development of the optimum spanload Winglets and their implications; 2) Horten Sailplanes; and 3) Flight Mechanics & Adverse yaw.

  1. Unsteady flow computation of oscillating flexible wings

    NASA Technical Reports Server (NTRS)

    Kandil, Osama A.; Chuang, H. Andrew; Salman, Ahmed A.

    1990-01-01

    The problem of unsteady flow around flexible wings is solved using the unsteady, compressible, thin-layer Navier-Stokes equations in conjunction with the unsteady, linearized, Navier-displacement equations. Starting with the initial shape of the wing, the Navier-Stokes equations are solved on an initial structured grid to obtain the steady-flow solution which is used for the initial conditions. The forced deformation motion of the wing boundaries is then applied, and the problem is solved accurately in time. During the time-accurate stepping, the Navier-displacement equations are used to solve for the grid deformation and sequently, the Navier-Stokes equations are used to solve for the flowfield. Two applications are presented; the first is for a pulsating oscillation of a bending-mode airfoil in transonic flow, and the second is for a bending-mode oscillation of a sharp-edged delta wing in supersonic flow.

  2. Left-Wing Extremism: The Current Threat

    SciTech Connect

    Karl A. Seger

    2001-04-30

    Left-wing extremism is ''alive and well'' both in the US and internationally. Although the current domestic terrorist threat within the U. S. is focused on right-wing extremists, left-wing extremists are also active and have several objectives. Leftist extremists also pose an espionage threat to U.S. interests. While the threat to the U.S. government from leftist extremists has decreased in the past decade, it has not disappeared. There are individuals and organizations within the U.S. who maintain the same ideology that resulted in the growth of left-wing terrorism in this country in the 1970s and 1980s. Some of the leaders from that era are still communicating from Cuba with their followers in the U.S., and new leaders and groups are emerging.

  3. Coriolis effects enhance lift on revolving wings.

    PubMed

    Jardin, T; David, L

    2015-03-01

    At high angles of attack, an aircraft wing stalls. This dreaded event is characterized by the development of a leading edge vortex on the upper surface of the wing, followed by its shedding which causes a drastic drop in the aerodynamic lift. At similar angles of attack, the leading edge vortex on an insect wing or an autorotating seed membrane remains robustly attached, ensuring high sustained lift. What are the mechanisms responsible for both leading edge vortex attachment and high lift generation on revolving wings? We review the three main hypotheses that attempt to explain this specificity and, using direct numerical simulations of the Navier-Stokes equations, we show that the latter originates in Coriolis effects. PMID:25871040

  4. Measurements of Supersonic Wing Tip Vortices

    NASA Technical Reports Server (NTRS)

    Smart, Michael K.; Kalkhoran, Iraj M.; Benston, James

    1994-01-01

    An experimental survey of supersonic wing tip vortices has been conducted at Mach 2.5 using small performed 2.25 chords down-stream of a semi-span rectangular wing at angle of attack of 5 and 10 degrees. The main objective of the experiments was to determine the Mach number, flow angularity and total pressure distribution in the core region of supersonic wing tip vortices. A secondary aim was to demonstrate the feasibility of using cone probes calibrated with a numerical flow solver to measure flow characteristics at supersonic speeds. Results showed that the numerically generated calibration curves can be used for 4-hole cone probes, but were not sufficiently accurate for conventional 5-hole probes due to nose bluntness effects. Combination of 4-hole cone probe measurements with independent pitot pressure measurements indicated a significant Mach number and total pressure deficit in the core regions of supersonic wing tip vortices, combined with an asymmetric 'Burger like' swirl distribution.

  5. Territoriality in the Red-winged Blackbird

    ERIC Educational Resources Information Center

    Newhouse, Chris

    1977-01-01

    Reports findings on research in Red-winged Blackbird territoriality and describes the educational potential of use of similar studies in the classroom. Territorial mapping and observational techniques are explained. (CS)

  6. Wing planform optimization via an adjoint method

    NASA Astrophysics Data System (ADS)

    Leoviriyakit, Kasidit

    This dissertation focuses on the problem of wing planform optimization for transonic aircraft based on flow simulation using Computational Fluid Dynamics (CFD) combined with an adjoint-gradient based numerical optimization procedure. The adjoint method, traditionally used for wing section design has been extended to cover planform variations and to compute the sensitivities of the structural weight of both the wing section and planform variations. The two relevant disciplines accounted for are the aerodynamics and structural weight. A simplified structural weight model is used for the optimization. Results of a variety of long range transports indicate that significant improvement in both aerodynamics and structures can be achieved simultaneously. The proof-of-concept optimal results indicate large improvements for both drag and structural weight. The work is an "enabling step" towards a realistic automated wing designed by a computer.

  7. The Design of Airplane Wing Ribs

    NASA Technical Reports Server (NTRS)

    Newlin, J A; Trayer, George W

    1931-01-01

    The purpose of this investigation was to obtain information for use in the design of truss and plywood forms, particularly with reference to wing ribs. Tests were made on many designs of wing ribs, comparing different types in various sizes. Many tests were also made on parallel-chord specimens of truss and plywood forms in place of the actual ribs and on parts of wing ribs, such as truss diagonals and sections of cap strips. It was found that for ribs of any size or proportions, when they were designed to obtain a well-balanced construction and were carefully manufactured, distinct types are of various efficiencies; the efficiency is based on the strength per unit of weight. In all types of ribs the heavier are the stronger per unit of weight. Reductions in the weight of wing ribs are accompanied even in efficient designs by a much greater proportional reduction in strength.

  8. Coriolis effects enhance lift on revolving wings

    NASA Astrophysics Data System (ADS)

    Jardin, T.; David, L.

    2015-03-01

    At high angles of attack, an aircraft wing stalls. This dreaded event is characterized by the development of a leading edge vortex on the upper surface of the wing, followed by its shedding which causes a drastic drop in the aerodynamic lift. At similar angles of attack, the leading edge vortex on an insect wing or an autorotating seed membrane remains robustly attached, ensuring high sustained lift. What are the mechanisms responsible for both leading edge vortex attachment and high lift generation on revolving wings? We review the three main hypotheses that attempt to explain this specificity and, using direct numerical simulations of the Navier-Stokes equations, we show that the latter originates in Coriolis effects.

  9. Mallard age and sex determination from wings

    USGS Publications Warehouse

    Carney, S.M.; Geis, A.D.

    1960-01-01

    This paper describes characters on the wing plumage of the mallard that indicate age and sex. A key outlines a logical order in which to check age and sex characters on wings. This method was tested and found to be more than 95 percent reliable, although it was found that considerable practice and training with known-age specimens was required to achieve this level of accuracy....The implications of this technique and the sampling procedure it permits are discussed. Wing collections could provide information on production, and, if coupled with a banding program could permit seasonal population estimates to be calculated. In addition, representative samples of wings would provide data to check the reliability of several other waterfowl surveys.

  10. Preparation of bionic nanostructures from butterfly wings and their low reflectivity of ultraviolet

    NASA Astrophysics Data System (ADS)

    Han, Z. W.; Niu, S. C.; Li, W.; Ren, L. Q.

    2013-06-01

    This letter presents a bionic study on Parnassius butterfly wings with a prominent ultraviolet (UV)-selective antireflection effect. An accurate SiO2 inverse replica of the nanostructure with a unique optical function from butterfly wings is prepared in multiscale by combining a sol-gel process and subsequent selective etching. It is found that the original nanostructures of biotemplate are well inherited and the excellent UV-antireflection function could be modulated by tunable parameters such as the replica spacing, width, distribution, and shape as well as formation.

  11. Improvement of Aerodynamic Performance of the Aero-Train by Controlling Wing-Wing Interaction Using Single-Slotted Flap

    NASA Astrophysics Data System (ADS)

    Yoon, Dong-Hee; Kohama, Yasuaki; Kikuchi, Satoshi; Kato, Takuma

    Aero-train is a new driving concept using aerodynamic technology under development by the Kohama Laboratory, Institute of Fluid Science, Tohoku University. It employs the wing-in-ground effect to enable travel at high speeds over land. Aero-train makes use of the ground effects of lift and side force between the wings and a U-shaped guideway for stability. The main wings have vertical wings at the tips, which are arranged in tandem to regulate the roll and yaw stability in the U-shaped guideway. However, the vertical wings deteriorate the lift-to-drag ratio of the Aero-train by aerodynamic interaction with the main wings. The present study was performed to improve the aerodynamic performance of the Aero-train by controlling wing-wing interaction. Installation of a single-slotted flap on the wings considerably improved the aerodynamic performance of the wings.

  12. Conceptual design for a laminar-flying-wing aircraft

    NASA Astrophysics Data System (ADS)

    Saeed, T. I.

    The laminar-flying-wing aircraft appears to be an attractive long-term prospect for reducing the environmental impact of commercial aviation. In assessing its potential, a relatively straightforward initial step is the conceptual design of a version with restricted sweep angle. Such a design is the topic of this thesis. Subject to constraints, this research aims to; provide insight into the parameters affecting practical laminar-flow-control suction power requirements; identify a viable basic design specification; and, on the basis of this, an assessment of the fuel efficiency through a detailed conceptual design study. It is shown that there is a minimum power requirement independent of the suction system design, associated with the stagnation pressure loss in the boundary layer. This requirement increases with aerofoil section thickness, but depends only weakly on Mach number and (for a thick, lightly-loaded laminar flying wing) lift coefficient. Deviation from the optimal suction distribution, due to a practical chamber-based architecture, is found to have very little effect on the overall suction coefficient. In the spanwise direction, through suitable choice of chamber depth, the pressure drop due to frictional and inertial effects may be rendered negligible. Finally, it is found that the pressure drop from the aerofoil surface to the pump collector ducts determines the power penalty. To identify the viable basic design specification, a high-level exploration of the laminar flying wing design space is performed. The characteristics of the design are assessed as a function of three parameters: thickness-to-chord ratio, wingspan, and unit Reynolds number. A feasible specification, with 20% thickness-to-chord, 80 m span and a unit Reynolds number of 8 x 106 m-1, is identified; it corresponds to a 187 tonne aircraft which cruises at Mach 0.67 and altitude 22,500 ft, with lift coefficient 0.14. On the basis of this specification, a detailed conceptual design is

  13. Butterfly wing color: A photonic crystal demonstration

    NASA Astrophysics Data System (ADS)

    Proietti Zaccaria, Remo

    2016-01-01

    We have theoretically modeled the optical behavior of a natural occurring photonic crystal, as defined by the geometrical characteristics of the Teinopalpus Imperialis butterfly. In particular, following a genetic algorithm approach, we demonstrate how its wings follow a triclinic crystal geometry with a tetrahedron unit base. By performing both photonic band analysis and transmission/reflection simulations, we are able to explain the characteristic colors emerging by the butterfly wings, thus confirming their crystal form.

  14. Numerical simulation of swept-wing flows

    NASA Technical Reports Server (NTRS)

    Reed, Helen L.

    1991-01-01

    The transition process characteristics of flows over swept wings were computationally modelled. The crossflow instability and crossflow/T-S wave interaction are analyzed through the numerical solution of the full three dimensional Navier-Stokes equations including unsteadiness, curvature, and sweep. The leading-edge region of a swept wing is considered in a three-dimensional spatial simulation with random disturbances as the initial conditions.

  15. Experiments with suction-type wings

    NASA Technical Reports Server (NTRS)

    Schrenk, O

    1935-01-01

    The present report collects the investigations of the past years which, while not as yet intended for use in construction, show different possibilities for the building of a suction-type wing and at the same time present some basic explanations concerning the problem of suction. Experiments and results with a thick wing profile are detailed as well as boundary layer removal by suction and sink action. Experiments with flap profiles are also included.

  16. The oscillating wing with aerodynamically balanced elevator

    NASA Technical Reports Server (NTRS)

    Kussner, H G; Schwartz, I

    1941-01-01

    The two-dimensional problem of the oscillating wing with aerodynamically balanced elevator is treated in the manner that the wing is replaced by a plate with bends and stages and the airfoil section by a mean line consisting of one or more straights. The computed formulas and tables permit, on these premises, the prediction of the pressure distribution and of the aerodynamic reactions of oscillating elevators and tabs with any position of elevator hinge in respect to elevator leading edge.

  17. Selection on Wing Allometry in Drosophila Melanogaster

    PubMed Central

    Weber, K. E.

    1990-01-01

    Five bivariate distributions of wing dimensions of Drosophila melanogaster were measured, in flies 1) subjected to four defined environmental regimes during development, 2) taken directly from nature in seven U.S. states, 3) selected in ten populations for change in wing form, and 4) sampled from 21 long inbred wild-type lines. Environmental stresses during development altered both wing size and the ratios of wing dimensions, but regardless of treatment all wing dimensions fell near a common allometric baseline in each bivariate distribution. The wings of wild-caught flies from seven widely separated localities, and of their laboratory-reared offspring, also fell along the same baselines. However, when flies were selected divergently for lateral offset from these developmental baselines, response to selection was rapid in every case. The mean divergence in offset between oppositely selected lines was 14.68 SD of the base population offset, after only 15 generations of selection at 20%. Measurements of 21 isofemale lines, founded from wild-caught flies and maintained in small populations for at least 22 years, showed large reductions in phenotypic variance of offsets within lines, but a large increase in the variance among lines. The variance of means of isofemale lines within collection localities was ten times the variance of means among localities of newly established wild lines. These observations show that much additive genetic variance exists for individual dimensions within the wing, such that bivariate developmental patterns can be changed in any direction by selection or by drift. The relative invariance of the allometric baselines of wing morphology in nature is most easily explained as the result of continuous natural selection around a local optimum of functional design. PMID:2127580

  18. Integrated technology wing study (oral presentation)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The design of a plan for a commercial transport manufacturer to integrate advanced technology into a new wing for a derivative and/or new aircraft that could enter service in the late 1980s to early 1990s time period is proposed. The development of a new wing for a derivative or a new long range commercial aircraft and the incorporation of cost effective technologies are studied. The decision provides guidelines for the best allocation of research funds.

  19. Calculations Of Transonic Flow About A Wing

    NASA Technical Reports Server (NTRS)

    Holst, Terry L.; Gundy, Karen L.; Flores, Jolen; Chaderjian, Neal; Kaynak, Univer; Thomas, Scott D.

    1988-01-01

    Report describes calculations of transonic airflows about wing in wind tunnel. Basic equations of flow used in study are Reynolds-averaged Navier-Stokes equations in strong conservation-law form. Equations of flow incorporated into finite-difference computer code called TNS (Transonic Navier-Stokes). Computational grid generated by solution of partial differential equations yielding smooth meshes conforming to surfaces of wing and wind tunnel.

  20. Determination of the characteristics of tapered wings

    NASA Technical Reports Server (NTRS)

    Anderson, Raymond F

    1937-01-01

    This report presents tables and charts for use in determining the characteristics of tapered wings. Theoretical factors are given from which the following characteristics of tapered wings may be found: the span lift distribution, the induced-angle-of attack distribution, the lift-curve slope, the angle of zero lift, the induced drag, the aerodynamic-center position, and the pitching moment about the aerodynamic center.

  1. Modal control of an oblique wing aircraft

    NASA Technical Reports Server (NTRS)

    Phillips, James D.

    1989-01-01

    A linear modal control algorithm is applied to the NASA Oblique Wing Research Aircraft (OWRA). The control law is evaluated using a detailed nonlinear flight simulation. It is shown that the modal control law attenuates the coupling and nonlinear aerodynamics of the oblique wing and remains stable during control saturation caused by large command inputs or large external disturbances. The technique controls each natural mode independently allowing single-input/single-output techniques to be applied to multiple-input/multiple-output systems.

  2. Aircraft noise propagation. [sound diffraction by wings

    NASA Technical Reports Server (NTRS)

    Hadden, W. J.; Pierce, A. D.

    1978-01-01

    Sound diffraction experiments conducted at NASA Langley Research Center to study the acoustical implications of the engine over wing configuration (noise-shielding by wing) and to provide a data base for assessing various theoretical approaches to the problem of aircraft noise reduction are described. Topics explored include the theory of sound diffraction around screens and wedges; the scattering of spherical waves by rectangular patches; plane wave diffraction by a wedge with finite impedence; and the effects of ambient flow and distribution sources.

  3. Shock interference heat transfer to tank configurations mated to a straight-wing space shuttle orbiter at Mach number 10.3. [investigated in a Langley hypersonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Crawford, D. H.

    1976-01-01

    Heat transfer was measured on a space shuttle-tank configuration with no mated orbiter in place and with the orbiter in 10 different mated positions. The orbiter-tank combination was tested at angles of attack of 0 deg and 5 deg, at a Mach number of 10.3, and at a free-stream Reynolds number of one million based on the length of the tank. Comparison of interference heat transfer with no-interference heat transfer shows that shock interference can increase the heat transfer to the tank by two orders of magnitude along the ray adjacent to the orbiter and can cause high temperature gradients along the tank skin. The relative axial location of the two mated vehicles determined the location of the sharp peaks of extreme heating as well as their magnitude. The other control variables (the angle of attack, the gap, and the cross-section shape) had significant effects that were not as consistent or as extreme.

  4. Numerical investigation of the aerodynamic and structural characteristics of a corrugated wing

    NASA Astrophysics Data System (ADS)

    Hord, Kyle

    Previous experimental studies on static, bio-inspired corrugated wings have shown that they produce favorable aerodynamic properties such as delayed stall compared to streamlined wings and flat plates at high Reynolds numbers (Re ≥ 4x104). The majority of studies have been carried out with scaled models of dragonfly forewings from the Aeshna Cyanea in either wind tunnels or water channels. In this thesis, the aerodynamics of a corrugated airfoil was studied using computational fluid dynamics methods at a low Reynolds number of 1000. Structural analysis was also performed using the commercial software SolidWorks 2009. The flow field is described by solving the incompressible Navier-Stokes equations on an overlapping grid using the pressure-Poisson method. The equations are discretized in space with second-order accurate central differences. Time integration is achieved through the second-order Crank-Nicolson implicit method. The complex vortex structures that form in the corrugated airfoil valleys and around the corrugated airfoil are studied in detail. Comparisons are made with experimental measurements from corrugated wings and also with simulations of a flat plate. Contrary to the studies at high Reynolds numbers, our study shows that at low Reynolds numbers the wing corrugation does not provide any aerodynamic benefit compared to a smoothed flat plate. Instead, the corrugated profile generates more pressure drag which is only partially offset by the reduction of friction drag, leading to more total drag than the flat plate. Structural analysis shows that the wing corrugation can increase the resistance to bending moments on the wing structure. A smoothed structure has to be three times thicker to provide the same stiffness. It was concluded the corrugated wing has the structural benefit to provide the same resistance to bending moments with a much reduced weight.

  5. A CFD-informed quasi-steady model of flapping wing aerodynamics

    PubMed Central

    Nakata, Toshiyuki; Liu, Hao; Bomphrey, Richard J.

    2016-01-01

    Aerodynamic performance and agility during flapping flight are determined by the combination of wing shape and kinematics. The degree of morphological and kinematic optimisation is unknown and depends upon a large parameter space. Aimed at providing an accurate and computationally inexpensive modelling tool for flapping-wing aerodynamics, we propose a novel CFD (computational fluid dynamics)-informed quasi-steady model (CIQSM), which assumes that the aerodynamic forces on a flapping wing can be decomposed into the quasi-steady forces and parameterised based on CFD results. Using least-squares fitting, we determine a set of proportional coefficients for the quasi-steady model relating wing kinematics to instantaneous aerodynamic force and torque; we calculate power with the product of quasi-steady torques and angular velocity. With the quasi-steady model fully and independently parameterised on the basis of high-fidelity CFD modelling, it is capable of predicting flapping-wing aerodynamic forces and power more accurately than the conventional blade element model (BEM) does. The improvement can be attributed to, for instance, taking into account the effects of the induced downwash and the wing tip vortex on the force generation and power consumption. Our model is validated by comparing the aerodynamics of a CFD model and the present quasi-steady model using the example case of a hovering hawkmoth. It demonstrates that the CIQSM outperforms the conventional BEM while remaining computationally cheap, and hence can be an effective tool for revealing the mechanisms of optimization and control of kinematics and morphology in flapping-wing flight for both bio-flyers and unmanned air systems. PMID:27346891

  6. Numerical study of the trailing vortex of a wing with wing-tip blowing

    NASA Technical Reports Server (NTRS)

    Lim, Hock-Bin

    1994-01-01

    Trailing vortices generated by lifting surfaces such as helicopter rotor blades, ship propellers, fixed wings, and canard control surfaces are known to be the source of noise, vibration, cavitation, degradation of performance, and other hazardous problems. Controlling these vortices is, therefore, of practical interest. The formation and behavior of the trailing vortices are studied in the present research. In addition, wing-tip blowing concepts employing axial blowing and spanwise blowing are studied to determine their effectiveness in controlling these vortices and their effects on the performance of the wing. The 3D, unsteady, thin-layer compressible Navier-Stokes equations are solved using a time-accurate, implicit, finite difference scheme that employs LU-ADI factorization. The wing-tip blowing is simulated using the actuator plane concept, thereby, not requiring resolution of the jet slot geometry. Furthermore, the solution blanking feature of the chimera scheme is used to simplify the parametric study procedure for the wing-tip blowing. Computed results are shown to compare favorably with experimental measurements. It is found that axial wing-tip blowing, although delaying the rolling-up of the trailing vortices and the near-field behavior of the flowfield, does not dissipate the circulation strength of the trailing vortex farther downstream. Spanwise wing-tip blowing has the effect of displacing the trailing vortices outboard and upward. The increased 'wing-span' due to the spanwise wing-tip blowing has the effect of lift augmentation on the wing and the strengthening of the trailing vortices. Secondary trailing vortices are created at high spanwise wing-tip blowing intensities.

  7. Survey - Applications of structural optimization methods to fixed wing aircraft and spacecraft

    NASA Technical Reports Server (NTRS)

    Miura, Hirokazu; Neill, Douglas J.

    1992-01-01

    Results of a technical survey of the practical applications of structural optimization methods in the U.S. aerospace industry through 1980s are summarized. One of the most important developments in the 80s is the more widespread acceptance of structural optimization as one of the design tools that support practical structural design. Another significant advance is the development of large software tools for production applications. Attention is also given to the tailoring of the computerized design process to the specific environment of each company. The two most important aspects of this tailoring are seamless and easy-to-use incorporation of structural optimization in the overall aerospace design/production process and multidisciplinary integration aimed at ultimate performance optimization of the final product. Some specific applications discussed include the X-29 forward swept wing demonstrator aircraft, composite wing and vertical tail program, fighter wing redesign evaluations, high speed aircraft design, and space structures.

  8. Optimization on a Network-based Parallel Computer System for Supersonic Laminar Wing Design

    NASA Technical Reports Server (NTRS)

    Garcia, Joseph A.; Cheung, Samson; Holst, Terry L. (Technical Monitor)

    1995-01-01

    A set of Computational Fluid Dynamics (CFD) routines and flow transition prediction tools are integrated into a network based parallel numerical optimization routine. Through this optimization routine, the design of a 2-D airfoil and an infinitely swept wing will be studied in order to advance the design cycle capability of supersonic laminar flow wings. The goal of advancing supersonic laminar flow wing design is achieved by wisely choosing the design variables used in the optimization routine. The design variables are represented by the theory of Fourier series and potential theory. These theories, combined with the parallel CFD flow routines and flow transition prediction tools, provide a design space for a global optimal point to be searched. Finally, the parallel optimization routine enables gradient evaluations to be performed in a fast and parallel fashion.

  9. Theoretical damping in roll and rolling moment due to differential wing incidence for slender cruciform wings and wing-body combinations

    NASA Technical Reports Server (NTRS)

    Adams, Gaynor J; DUGAN DUANE W

    1952-01-01

    A method of analysis based on slender-wing theory is developed to investigate the characteristics in roll of slender cruciform wings and wing-body combinations. The method makes use of the conformal mapping processes of classical hydrodynamics which transform the region outside a circle and the region outside an arbitrary arrangement of line segments intersecting at the origin. The method of analysis may be utilized to solve other slender cruciform wing-body problems involving arbitrarily assigned boundary conditions. (author)

  10. Calculation of the longitudinal aerodynamic characteristics of wing-flap configurations with externally blown flaps

    NASA Technical Reports Server (NTRS)

    Mendenhall, M. R.; Spangler, S. B.; Nielsen, J. N.; Goodwin, F. K.

    1976-01-01

    A theoretical investigation was carried out to extend and improve an existing method for predicting the longitudinal characteristics of wing flap configurations with externally blown flaps (EBF). Two potential flow models were incorporated into the prediction method: a wing and flap lifting-surface model and a turbofan engine wake model. The wing-flap model uses a vortex-lattice approach to represent the wing and flaps. The jet wake model consists of a series of closely spaced vortex rings normal to a centerline which may have vertical and lateral curvature to conform to the local flow field beneath the wing and flaps. Comparisons of measured and predicted pressure distributions, span load distributions on each lifting surface, and total lift and pitching moment coefficients on swept and unswept EBF configurations are included. A wide range of thrust coefficients and flap deflection angles is considered at angles of attack up to the onset of stall. Results indicate that overall lift and pitching-moment coefficients are predicted reasonably well over the entire range. The predicted detailed load distributions are qualitatively correct and show the peaked loads at the jet impingement points, but the widths and heights of the load peaks are not consistently predicted.

  11. Using adjoint-based optimization to study wing flexibility in flapping flight

    NASA Astrophysics Data System (ADS)

    Wei, Mingjun; Xu, Min; Dong, Haibo

    2014-11-01

    In the study of flapping-wing flight of birds and insects, it is important to understand the impact of wing flexibility/deformation on aerodynamic performance. However, the large control space from the complexity of wing deformation and kinematics makes usual parametric study very difficult or sometimes impossible. Since the adjoint-based approach for sensitivity study and optimization strategy is a process with its cost independent of the number of input parameters, it becomes an attractive approach in our study. Traditionally, adjoint equation and sensitivity are derived in a fluid domain with fixed solid boundaries. Moving boundary is only allowed when its motion is not part of control effort. Otherwise, the derivation becomes either problematic or too complex to be feasible. Using non-cylindrical calculus to deal with boundary deformation solves this problem in a very simple and still mathematically rigorous manner. Thus, it allows to apply adjoint-based optimization in the study of flapping wing flexibility. We applied the ``improved'' adjoint-based method to study the flexibility of both two-dimensional and three-dimensional flapping wings, where the flapping trajectory and deformation are described by either model functions or real data from the flight of dragonflies. Supported by AFOSR.

  12. A Comparison of Metallic, Composite and Nanocomposite Optimal Transonic Transport Wings

    NASA Technical Reports Server (NTRS)

    Kennedy, Graeme J.; Kenway, Gaetan K. W.; Martins, Joaquim R. R.

    2014-01-01

    Current and future composite material technologies have the potential to greatly improve the performance of large transport aircraft. However, the coupling between aerodynamics and structures makes it challenging to design optimal flexible wings, and the transonic flight regime requires high fidelity computational models. We address these challenges by solving a series of high-fidelity aerostructural optimization problems that explore the design space for the wing of a large transport aircraft. We consider three different materials: aluminum, carbon-fiber reinforced composites and an hypothetical composite based on carbon nanotubes. The design variables consist of both aerodynamic shape (including span), structural sizing, and ply angle fractions in the case of composites. Pareto fronts with respect to structural weight and fuel burn are generated. The wing performance in each case is optimized subject to stress and buckling constraints. We found that composite wings consistently resulted in lower fuel burn and lower structural weight, and that the carbon nanotube composite did not yield the increase in performance one would expect from a material with such outstanding properties. This indicates that there might be diminishing returns when it comes to the application of advanced materials to wing design, requiring further investigation.

  13. Sensitivity Analysis of Flutter Response of a Wing Incorporating Finite-Span Corrections

    NASA Technical Reports Server (NTRS)

    Issac, Jason Cherian; Kapania, Rakesh K.; Barthelemy, Jean-Francois M.

    1994-01-01

    Flutter analysis of a wing is performed in compressible flow using state-space representation of the unsteady aerodynamic behavior. Three different expressions are used to incorporate corrections due to the finite-span effects of the wing in estimating the lift-curve slope. The structural formulation is based on a Rayleigh-Pitz technique with Chebyshev polynomials used for the wing deflections. The aeroelastic equations are solved as an eigen-value problem to determine the flutter speed of the wing. The flutter speeds are found to be higher in these cases, when compared to that obtained without accounting for the finite-span effects. The derivatives of the flutter speed with respect to the shape parameters, namely: aspect ratio, area, taper ratio and sweep angle, are calculated analytically. The shape sensitivity derivatives give a linear approximation to the flutter speed curves over a range of values of the shape parameter which is perturbed. Flutter and sensitivity calculations are performed on a wing using a lifting-surface unsteady aerodynamic theory using modules from a system of programs called FAST.

  14. Nonlinear Aerodynamics and the Design of Wing Tips

    NASA Technical Reports Server (NTRS)

    Kroo, Ilan

    1991-01-01

    The analysis and design of wing tips for fixed wing and rotary wing aircraft still remains part art, part science. Although the design of airfoil sections and basic planform geometry is well developed, the tip regions require more detailed consideration. This is important because of the strong impact of wing tip flow on wing drag; although the tip region constitutes a small portion of the wing, its effect on the drag can be significant. The induced drag of a wing is, for a given lift and speed, inversely proportional to the square of the wing span. Concepts are proposed as a means of reducing drag. Modern computational methods provide a tool for studying these issues in greater detail. The purpose of the current research program is to improve the understanding of the fundamental issues involved in the design of wing tips and to develop the range of computational and experimental tools needed for further study of these ideas.

  15. Imaging and Laser Spectroscopy Investigation of Insect Wings

    NASA Astrophysics Data System (ADS)

    Shiver, Tegan; Lawhead, Carlos; Anderson, Josiah; Cooper, Nathan; Ujj, Laszlo; Pall Life Sciences Collaboration

    2014-03-01

    Measuring the surface morphology and chemical composition of insect wings is important to understand the extreme mechanical properties and the biophysical functionalities of the wings. We have measured the image of the membrane of the cicada (genus Tibicen) wing with the help of Scanning Electron Microscopy (SEM). The results confirm the existing periodic structure of the wing measured previously. The SEM imaging can be used to measure the surface morphology of any insect species wings. The physical surface structure of the cicada wing is an example of a new class of biomaterials that can kill bacteria on contact. In order to identify the chemical composition of the wing, we have measured the vibrational spectra of the wing's membrane (Raman and CARS). The measured spectra are consistent with the original assumption that the wing membrane is composed of protein, wax, and chitin. The results of these studies can be used to make artificial materials in the future.

  16. Functional Gustatory Role of Chemoreceptors in Drosophila Wings.

    PubMed

    Raad, Hussein; Ferveur, Jean-François; Ledger, Neil; Capovilla, Maria; Robichon, Alain

    2016-05-17

    Neuroanatomical evidence argues for the presence of taste sensilla in Drosophila wings; however, the taste physiology of insect wings remains hypothetical, and a comprehensive link to mechanical functions, such as flight, wing flapping, and grooming, is lacking. Our data show that the sensilla of the Drosophila anterior wing margin respond to both sweet and bitter molecules through an increase in cytosolic Ca(2+) levels. Conversely, genetically modified flies presenting a wing-specific reduction in chemosensory cells show severe defects in both wing taste signaling and the exploratory guidance associated with chemodetection. In Drosophila, the chemodetection machinery includes mechanical grooming, which facilitates the contact between tastants and wing chemoreceptors, and the vibrations of flapping wings that nebulize volatile molecules as carboxylic acids. Together, these data demonstrate that the Drosophila wing chemosensory sensilla are a functional taste organ and that they may have a role in the exploration of ecological niches. PMID:27160896

  17. Effect of wing flexibility in dragonfly hovering flight

    NASA Astrophysics Data System (ADS)

    Naidu, Vishal; Young, John; Lai, Joseph

    2011-11-01

    Dragonflies have two pairs of tandem wings, which can be operated independently. Most studies on tandem wings are based on rigid wings, which is in strong contradiction to the natural, flexible dragonfly wings. The effect of wing flexibility in tandem wings is little known. We carry out a comparative, computational study between rigid and flexible, dragonfly shaped wings for hovering flight. In rigid wings during downstroke, a leading edge vortex (LEV) is formed on the upper surface, which forms a low pressure zone. This conical LEV joins the tip vortex and shortly after the mid downstroke when the wing starts to rotate, these vortices are gradually shed resulting in a drop in lift. The vortex system creates a net downwards momentum in the form of a jet. The flexible wings while in motion deform due to aerodynamic and inertial forces. Since there is a strong interaction between wing deformation and air flow around the deformed wings, flexible wing simulations are carried out using a two way fluid structure interaction. The effect of wing flexibility on the flow structure and the subsequent effect on the aerodynamic forces will be studied and presented.

  18. Wing Torsional Stiffness Tests of the Active Aeroelastic Wing F/A-18 Airplane

    NASA Technical Reports Server (NTRS)

    Lokos, William A.; Olney, Candida D.; Crawford, Natalie D.; Stauf, Rick; Reichenbach, Eric Y.

    2002-01-01

    The left wing of the Active Aeroelastic Wing (AAW) F/A-18 airplane has been ground-load-tested to quantify its torsional stiffness. The test has been performed at the NASA Dryden Flight Research Center in November 1996, and again in April 2001 after a wing skin modification was performed. The primary objectives of these tests were to characterize the wing behavior before the first flight, and provide a before-and-after measurement of the torsional stiffness. Two streamwise load couples have been applied. The wing skin modification is shown to have more torsional flexibility than the original configuration has. Additionally, structural hysteresis is shown to be reduced by the skin modification. Data comparisons show good repeatability between the tests.

  19. Experimental investigation of a flapping wing model

    NASA Astrophysics Data System (ADS)

    Hubel, Tatjana Y.; Tropea, Cameron

    2009-05-01

    The main objective of this research study was to investigate the aerodynamic forces of an avian flapping wing model system. The model size and the flow conditions were chosen to approximate the flight of a goose. Direct force measurements, using a three-component balance, and PIV flow field measurements parallel and perpendicular to the oncoming flow, were performed in a wind tunnel at Reynolds numbers between 28,000 and 141,000 (3-15 m/s), throughout a range of reduced frequencies between 0.04 and 0.20. The appropriateness of quasi-steady assumptions used to compare 2D, time-averaged particle image velocimetry (PIV) measurements in the wake with direct force measurements was evaluated. The vertical force coefficient for flapping wings was typically significantly higher than the maximum coefficient of the fixed wing, implying the influence of unsteady effects, such as delayed stall, even at low reduced frequencies. This puts the validity of the quasi-steady assumption into question. The (local) change in circulation over the wing beat cycle and the circulation distribution along the wingspan were obtained from the measurements in the tip and transverse vortex planes. Flow separation could be observed in the distribution of the circulation, and while the circulation derived from the wake measurements failed to agree exactly with the absolute value of the circulation, the change in circulation over the wing beat cycle was in excellent agreement for low and moderate reduced frequencies. The comparison between the PIV measurements in the two perpendicular planes and the direct force balance measurements, show that within certain limitations the wake visualization is a powerful tool to gain insight into force generation and the flow behavior on flapping wings over the wing beat cycle.

  20. Experimental investigation of a flapping wing model

    NASA Astrophysics Data System (ADS)

    Hubel, Tatjana Y.; Tropea, Cameron

    The main objective of this research study was to investigate the aerodynamic forces of an avian flapping wing model system. The model size and the flow conditions were chosen to approximate the flight of a goose. Direct force measurements, using a three-component balance, and PIV flow field measurements parallel and perpendicular to the oncoming flow, were performed in a wind tunnel at Reynolds numbers between 28,000 and 141,000 (3-15 m/s), throughout a range of reduced frequencies between 0.04 and 0.20. The appropriateness of quasi-steady assumptions used to compare 2D, time-averaged particle image velocimetry (PIV) measurements in the wake with direct force measurements was evaluated. The vertical force coefficient for flapping wings was typically significantly higher than the maximum coefficient of the fixed wing, implying the influence of unsteady effects, such as delayed stall, even at low reduced frequencies. This puts the validity of the quasi-steady assumption into question. The (local) change in circulation over the wing beat cycle and the circulation distribution along the wingspan were obtained from the measurements in the tip and transverse vortex planes. Flow separation could be observed in the distribution of the circulation, and while the circulation derived from the wake measurements failed to agree exactly with the absolute value of the circulation, the change in circulation over the wing beat cycle was in excellent agreement for low and moderate reduced frequencies. The comparison between the PIV measurements in the two perpendicular planes and the direct force balance measurements, show that within certain limitations the wake visualization is a powerful tool to gain insight into force generation and the flow behavior on flapping wings over the wing beat cycle.

  1. Flow field of flexible flapping wings

    NASA Astrophysics Data System (ADS)

    Sallstrom, Erik

    The agility and maneuverability of natural fliers would be desirable to incorporate into engineered micro air vehicles (MAVs). However, there is still much for engineers to learn about flapping flight in order to understand how such vehicles can be built for efficient flying. The goal of this study is to develop a methodology for capturing high quality flow field data around flexible flapping wings in a hover environment and to interpret it to gain a better understanding of how aerodynamic forces are generated. The flow field data was captured using particle image velocimetry (PIV) and required that measurements be taken around a repeatable flapping motion to obtain phase-averaged data that could be studied throughout the flapping cycle. Therefore, the study includes the development of flapping devices with a simple repeatable single degree of freedom flapping motion. The acquired flow field data has been examined qualitatively and quantitatively to investigate the mechanisms behind force production in hovering flight and to relate it to observations in previous research. Specifically, the flow fields have been investigated around a rigid wing and several carbon fiber reinforced flexible membrane wings. Throughout the whole study the wings were actuated with either a sinusoidal or a semi-linear flapping motion. The semi-linear flapping motion holds the commanded angular velocity nearly constant through half of each half-stroke while the sinusoidal motion is always either accelerating or decelerating. The flow fields were investigated by examining vorticity and vortex structures, using the Q criterion as the definition for the latter, in two and three dimensions. The measurements were combined with wing deflection measurements to demonstrate some of the key links in how the fluid-structure interactions generated aerodynamic forces. The flow fields were also used to calculate the forces generated by the flapping wings using momentum balance methods which yielded

  2. Metallic materials for the space shuttle.

    NASA Technical Reports Server (NTRS)

    Tavassoli, A. A.

    1972-01-01

    The need for further development and reevaluation of current space-vehicle materials (intended for a single mission) to meet the long-time requirements of a space shuttle is demonstrated. Leading metallic material candidates and their properties are tabulated for a delta-wing space shuttle configuration with a metallic thermal protection system.

  3. Optimization of the leading edge segment of a corrugated wing

    NASA Astrophysics Data System (ADS)

    Khurana, Manas; Chahl, Javaan

    2014-03-01

    Insect wings consist of flat plates of membranes stiffened by spars. The effect of this structure is that the wings appear as corrugated surfaces when considered on chordwise sections. We know that aerodynamically efficient insects such as a dragonfly engage in fixed wing flight modes for extended periods. The analysis in the literature has shown that the aerodynamic efficiency (cl/cd) of a corrugated aerofoil is sensitive to Reynolds number (Re) and angle-of-attack (AoA), yet the conclusions established are on the basis of flow analysis on a single baseline shape only. The sample size of the aerofoils must be extended further so that the influence and merits of corrugated shape features can be established. In this work, a design-of-experiments (DoE) approach is applied to induce systematic shape perturbations on a select, off-the-shelf baseline shape one feature at a time over a set number of increments. At each shape increment, the aerodynamic forces are established using a high fidelity CFD solver. The design space is modeled at a Re of 20,000 and 34,000 and at flow angle of 4.0° to represent a Micro Air Vehicle (MAV) in glide. The results confirmed the importance of the leading and trailing edge deflections on cl/cd. At Re = 20, 000, cl/cd of a corrugated aerofoil with deflection at the leading edge region only is 16% higher than the baseline shape, and 39% higher than the flat plate. At Re = 34, 000, cl/cd performance is sensitive to the trailing edge deflection. At the optimum deflection setting, cl/cd is 18% higher than the baseline shape and 23% higher than the flat plate. The results confirm that the leading and trailing edge deflections are critical to cl/cd for a MAV in glide.

  4. Mission adaptive wing soars at NASA Facility

    NASA Technical Reports Server (NTRS)

    Rahn, D.; Reinertson, L.

    1986-01-01

    Research pilots have flown the Mission Adaptive Wing (MAW) aircraft, a highly modified F-111 jet fighter, from subsonic speeds up to Mach 1.4 in initial flight tests. The inital test flights are clearing the envelope with the wings flexed at various curvatures. This process allows further research data to be safely gathered so that designers of future variable camber wing aircraft have the best information possible. The altitude envelope was cleared from 27,500 down to 7,500 feet where denser air can cause more stress on the aircraft. Testing with the aircraft was conducted with wing sweep angles of 26 and 58 degrees. At the conclusion of the performance tests in the manual configuration, the system will be reconfigured for automatic mode tests. The limited automatic modes include maneuver camber control where the wings are deflected automatically to the best lift versus drag combination for a particular speed; cruise camber control which can help protect the aircraft from high G stresses; and maneuver enhancement/gust alleviation which is designed to improve the aircraft's up and down movement response to pilot commands and reduce the aircraft response to turbulence.

  5. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight. PMID:27030773

  6. Ring Wing for an underwater missile

    NASA Astrophysics Data System (ADS)

    August, Henry; Carapezza, Edward

    Hughes Aircraft has performed exploratory wind tunnel studies of compressed carriage missile designs having extendable Ring Wing and wrap-around tail control surfaces. These force and moment data indicate that significant improvements in a missile's lift and aerodynamic efficiency can be realized. Low speed test results of these data were used to estimate potential underwater improved hydrodynamic characteristics that a Ring Wing and wrap-around tails can bring to an advanced torpedo design. Estimates of improved underwater flight performance of a heavyweight torpedo (4000 lbs.) having an extendable Ring Wing and wrap-around tails were made. The compressed volume design of this underwater missile is consistent with tube-launch constraints and techniques. Study results of this novel Ring Wing torpedo design include extended flight performance in range and endurance due to lowered speeds capable of sustaining underwater level flight. Correspondingly, reduced radiated noise for enhanced stealth qualities is projected. At high speeds, greater maneuverability and aimpoint selection can be realized by a Ring Wing underwater missile.

  7. A Flight Comparison of Conventional Ailerons on a Rectangular Wing and of Conventional and Floating Wing-Tip Ailerons on a Tapered Wing

    NASA Technical Reports Server (NTRS)

    Soule, H A; Gracey, W

    1938-01-01

    Report presents the results of flight tests comparing the relative effectiveness of conventional ailerons of the same size on wings of rectangular and tapered plan forms made with a Fairchild 22 airplane. Information is included comparing conventional and floating wing-tip ailerons on a tapered wing. The results showed that the conventional ailerons were somewhat more effective on the tapered than on the rectangular wing. The difference, however, was so small as to be imperceptible to the pilots. The floating wing-tip ailerons were only half as effective as the conventional ailerons and, for this reason, were considered unsatisfactory.

  8. Insect-like flapping wing mechanism based on a double spherical Scotch yoke

    PubMed Central

    Galiński, Cezary; Żbikowski, Rafał

    2005-01-01

    We describe the rationale, concept, design and implementation of a fixed-motion (non-adjustable) mechanism for insect-like flapping wing micro air vehicles in hover, inspired by two-winged flies (Diptera). This spatial (as opposed to planar) mechanism is based on the novel idea of a double spherical Scotch yoke. The mechanism was constructed for two main purposes: (i) as a test bed for aeromechanical research on hover in flapping flight, and (ii) as a precursor design for a future flapping wing micro air vehicle. Insects fly by oscillating (plunging) and rotating (pitching) their wings through large angles, while sweeping them forwards and backwards. During this motion the wing tip approximately traces a ‘figure-of-eight’ or a ‘banana’ and the wing changes the angle of attack (pitching) significantly. The kinematic and aerodynamic data from free-flying insects are sparse and uncertain, and it is not clear what aerodynamic consequences different wing motions have. Since acquiring the necessary kinematic and dynamic data from biological experiments remains a challenge, a synthetic, controlled study of insect-like flapping is not only of engineering value, but also of biological relevance. Micro air vehicles are defined as flying vehicles approximately 150 mm in size (hand-held), weighing 50–100 g, and are developed to reconnoitre in confined spaces (inside buildings, tunnels, etc.). For this application, insect-like flapping wings are an attractive solution and hence the need to realize the functionality of insect flight by engineering means. Since the semi-span of the insect wing is constant, the kinematics are spatial; in fact, an approximate figure-of-eight/banana is traced on a sphere. Hence a natural mechanism implementing such kinematics should be (i) spherical and (ii) generate mathematically convenient curves expressing the figure-of-eight/banana shape. The double spherical Scotch yoke design has property (i) by definition and achieves (ii) by

  9. Principle of bio-inspired insect wing rotational hinge design

    NASA Astrophysics Data System (ADS)

    Fei, Fan

    A principle for designing and fabricating bio-inspired miniature artificial insect flapping wing using flexure rotational hinge design is presented. A systematic approach of selecting rotational hinge stiffness value is proposed. Based on the understanding of flapping wing aerodynamics, a dynamic simulation is constructed using the established quasi-steady model and the wing design. Simulations were performed to gain insight on how different parameters affect the wing rotational response. Based on system resonance a model to predict the optimal rotational hinge stiffness based on given wing parameter and flapping wing kinematic is proposed. By varying different wing parameters, the proposed method is shown to be applicable to a wide range of wing designs with different sizes and shapes. With the selected hinge stiffness value, aspects of the rotational joint design is discussed and an integrated wing-hinge structure design using laminated carbon fiber and polymer film is presented. Manufacturing process of such composite structure is developed to achieve high accuracy and repeatability. The yielded hinge stiffness is verified by measurements. To validate the proposed model, flapping wing experiments were conducted. A flapping actuation set up is built using DC motor and a controller is implemented on a microcontroller to track desired wing stroke kinematic. Wing stroke and rotation kinematic were extracted using a high speed camera and the lift generation is evaluated. A total of 49 flapping experiments were presented, experimental data shows good correlation with the model's prediction. With the wing rotational hinge stiffness designed so that the rotational resonant frequency is twice as the stroke frequency, the resulting wing rotation generates near optimal lift. With further simulation, the proposed model shows low sensitivity to wing parameter variation. As a result, giving a design parameter of a flapping wing robot platform, the proposed principle can

  10. Design and demonstration of a small expandable morphing wing

    NASA Astrophysics Data System (ADS)

    Heryawan, Yudi; Park, Hoon C.; Goo, Nam S.; Yoon, Kwang J.; Byun, Yung H.

    2005-05-01

    In this paper, we present design, manufacturing, and wind tunnel test for a small-scale expandable morphing wing. The wing is separated into inner and outer wings as a typical bird wing. The part from leading edge of the wing chord is made of carbon composite strip and balsa. The remaining part is covered with curved thin carbon fiber composite mimicking wing feathers. The expandable wing is driven by a small DC motor, reduction gear, and fiber reinforced composite linkages. Rotation of the motor is switched to push-pull linear motion by a screw and the linear motion of the screw is transferred to linkages to create wing expansion and folding motions. The wing can change its aspect ratio from 4.7 to 8.5 in about 2 seconds and the speed can be controlled. Two LIPCAs (Lightweight Piezo-Composite Actuators) are attached under the inner wing section and activated on the expanded wing state to modify camber of the wing. In the wind tunnel test, change of lift, drag, and pitching moment during wing expansion have been investigated for various angles of attack. The LIPCA activation has created significant additional lift.

  11. Gliding swifts attain laminar flow over rough wings.

    PubMed

    Lentink, David; de Kat, Roeland

    2014-01-01

    Swifts are among the most aerodynamically refined gliding birds. However, the overlapping vanes and protruding shafts of their primary feathers make swift wings remarkably rough for their size. Wing roughness height is 1-2% of chord length on the upper surface--10,000 times rougher than sailplane wings. Sailplanes depend on extreme wing smoothness to increase the area of laminar flow on the wing surface and minimize drag for extended glides. To understand why the swift does not rely on smooth wings, we used a stethoscope to map laminar flow over preserved wings in a low-turbulence wind tunnel. By combining laminar area, lift, and drag measurements, we show that average area of laminar flow on swift wings is 69% (n = 3; std 13%) of their total area during glides that maximize flight distance and duration--similar to high-performance sailplanes. Our aerodynamic analysis indicates that swifts attain laminar flow over their rough wings because their wing size is comparable to the distance the air travels (after a roughness-induced perturbation) before it transitions from laminar to turbulent. To interpret the function of swift wing roughness, we simulated its effect on smooth model wings using physical models. This manipulation shows that laminar flow is reduced and drag increased at high speeds. At the speeds at which swifts cruise, however, swift-like roughness prolongs laminar flow and reduces drag. This feature gives small birds with rudimentary wings an edge during the evolution of glide performance. PMID:24964089

  12. Lift on Flexible and Rigid Cambered Wings at High Incidence

    NASA Astrophysics Data System (ADS)

    Jones, Anya; Mancini, Peter; Granlund, Kenneth; Ol, Michael

    2014-11-01

    The effects of camber and camber change due to elastic deflection of a membrane wing were investigated for wings in rectilinear translation with parameter variations in wing incidence and acceleration. Direct force and moment measurements were performed on a rigid flat plate wing, rigid cambered wings, and a membrane wing. Features in the force histories were further examined via flow visualization by planar laser illumination of fluorescent dye. Below 10 degrees of incidence, Wagner's approximation accurately predicts the time-evolution of lift for the rigid wings. At higher incidence, flow separation results in force transients, and the effect of wing camber is no longer additive. Both the rigid flat plate and rigid cambered wings reach peak lift at a 35 degree angle of attack, whereas the flexible wing experiences stall delay and reaches peak lift at 50 degrees. Due to the aeroelasticity of the flexible membrane, flow over the suction surface remains attached for much higher incidence angles than for the rigid wings. For incidence angles less than 30 degrees, the peak lift of the flexible wing is lower than that of its rigid counterparts. Beyond 30 degrees, the flexible wing experiences an aeroelastically induced stall delay that allows lift to exceed the rigid analogs. This work was supported by the Air Force Office of Scientific Research (AFOSR) Summer Faculty Fellowship Program and the U.S. Army Research Laboratory under the Micro Autonomous Systems and Technology (MAST) program.

  13. Gliding Swifts Attain Laminar Flow over Rough Wings

    PubMed Central

    Lentink, David; de Kat, Roeland

    2014-01-01

    Swifts are among the most aerodynamically refined gliding birds. However, the overlapping vanes and protruding shafts of their primary feathers make swift wings remarkably rough for their size. Wing roughness height is 1–2% of chord length on the upper surface—10,000 times rougher than sailplane wings. Sailplanes depend on extreme wing smoothness to increase the area of laminar flow on the wing surface and minimize drag for extended glides. To understand why the swift does not rely on smooth wings, we used a stethoscope to map laminar flow over preserved wings in a low-turbulence wind tunnel. By combining laminar area, lift, and drag measurements, we show that average area of laminar flow on swift wings is 69% (n = 3; std 13%) of their total area during glides that maximize flight distance and duration—similar to high-performance sailplanes. Our aerodynamic analysis indicates that swifts attain laminar flow over their rough wings because their wing size is comparable to the distance the air travels (after a roughness-induced perturbation) before it transitions from laminar to turbulent. To interpret the function of swift wing roughness, we simulated its effect on smooth model wings using physical models. This manipulation shows that laminar flow is reduced and drag increased at high speeds. At the speeds at which swifts cruise, however, swift-like roughness prolongs laminar flow and reduces drag. This feature gives small birds with rudimentary wings an edge during the evolution of glide performance. PMID:24964089

  14. Investigating the Force Production of Functionally-Graded Flexible Wings in Flapping Wing Flight

    NASA Astrophysics Data System (ADS)

    Mudbhari, Durlav; Erdogan, Malcolm; He, Kai; Bateman, Daniel; Lipkis, Rory; Moored, Keith

    2015-11-01

    Birds, insects and bats oscillate their wings to propel themselves over long distances and to maneuver with unprecedented agility. A key element to achieve their impressive aerodynamic performance is the flexibility of their wings. Numerous studies have shown that homogeneously flexible wings can enhance force production, propulsive efficiency and lift efficiency. Yet, animal wings are not homogenously flexible, but instead have varying material properties. The aim of this study is to characterize the force production and energetics of functionally-graded flexible wings. A partially-flexible wing composed of a rigid section and a flexible section is used as a first-order model of functionally-graded materials. The flexion occurs in the spanwise direction and it is affected by the spanwise flexion ratio, that is, the ratio of the length of the rigid section compared to the total span length. By varying the flexion ratio as well as the material properties of the flexible section, the study aims to examine the force production and energetics of flapping flight with functionally-graded flexible wings. Supported by the Office of Naval Research under Program Director Dr. Bob Brizzolara, MURI grant number N00014-14-1-0533.

  15. Oblique wing transonic transport configuration development

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Studies of transport aircraft designed for boom-free supersonic flight show the variable sweep oblique wing to be the most efficient configuration for flight at low supersonic speeds. Use of this concept leads to a configuration that is lighter, quieter, and more fuel efficient than symmetric aircraft designed for the same mission. Aerodynamic structural, weight, aeroelastic and flight control studies show the oblique wing concept to be technically feasible. Investigations are reported for wing planform and thickness, pivot design and weight estimation, engine cycle (bypass ratio), and climb, descent and reserve fuel. Results are incorporated into a final configuration. Performance, weight, and balance characteristics are evaluated. Flight control requirements are reviewed, and areas in which further research is needed are identified.

  16. Computational fluid dynamics of airfoils and wings

    NASA Technical Reports Server (NTRS)

    Garabedian, P.; Mcfadden, G.

    1982-01-01

    It is pointed out that transonic flow is one of the fields where computational fluid dynamics turns out to be most effective. Codes for the design and analysis of supercritical airfoils and wings have become standard tools of the aircraft industry. The present investigation is concerned with mathematical models and theorems which account for some of the progress that has been made. The most successful aerodynamics codes are those for the analysis of flow at off-design conditions where weak shock waves appear. A major breakthrough was achieved by Murman and Cole (1971), who conceived of a retarded difference scheme which incorporates artificial viscosity to capture shocks in the supersonic zone. This concept has been used to develop codes for the analysis of transonic flow past a swept wing. Attention is given to the trailing edge and the boundary layer, entropy inequalities and wave drag, shockless airfoils, and the inverse swept wing code.

  17. General Potential Theory of Arbitrary Wing Sections

    NASA Technical Reports Server (NTRS)

    Theodorsen, T.; Garrick, I. E.

    1979-01-01

    The problem of determining the two dimensional potential flow around wing sections of any shape is examined. The problem is condensed into the compact form of an integral equation capable of yielding numerical solutions by a direct process. An attempt is made to analyze and coordinate the results of earlier studies relating to properties of wing sections. The existing approximate theory of thin wing sections and the Joukowski theory with its numerous generalizations are reduced to special cases of the general theory of arbitrary sections, permitting a clearer perspective of the entire field. The method which permits the determination of the velocity at any point of an arbitrary section and the associated lift and moments is described. The method is also discussed in terms for developing new shapes of preassigned aerodynamical properties.

  18. Wing-Body Aeroelasticity on Parallel Computers

    NASA Technical Reports Server (NTRS)

    Guruswamy, Guru P.; Byun, Chansup

    1996-01-01

    This article presents a procedure for computing the aeroelasticity of wing-body configurations on multiple-instruction, multiple-data parallel computers. In this procedure, fluids are modeled using Euler equations discretized by a finite difference method, and structures are modeled using finite element equations. The procedure is designed in such a way that each discipline can be developed and maintained independently by using a domain decomposition approach. A parallel integration scheme is used to compute aeroelastic responses by solving the coupled fluid and structural equations concurrently while keeping modularity of each discipline. The present procedure is validated by computing the aeroelastic response of a wing and comparing with experiment. Aeroelastic computations are illustrated for a high speed civil transport type wing-body configuration.

  19. Aeroelastic Analysis of Modern Complex Wings

    NASA Technical Reports Server (NTRS)

    Kapania, Rakesh K.; Bhardwaj, Manoj K.; Reichenbach, Eric; Guruswamy, Guru P.

    1996-01-01

    A process is presented by which aeroelastic analysis is performed by using an advanced computational fluid dynamics (CFD) code coupled with an advanced computational structural dynamics (CSD) code. The process is demonstrated on an F/A-18 Stabilator using NASTD (an in-house McDonnell Douglas Aerospace East CFD code) coupled with NASTRAN. The process is also demonstrated on an aeroelastic research wing (ARW-2) using ENSAERO (an in-house NASA Ames Research Center CFD code) coupled with a finite element wing-box structures code. Good results have been obtained for the F/A-18 Stabilator while results for the ARW-2 supercritical wing are still being obtained.

  20. Smithornis broadbills produce loud wing song by aeroelastic flutter of medial primary wing feathers.

    PubMed

    Clark, Christopher J; Kirschel, Alexander N G; Hadjioannou, Louis; Prum, Richard O

    2016-04-01

    Broadbills in the genus Smithornis produce a loud brreeeeet during a distinctive flight display. It has been posited that this klaxon-like sound is generated non-vocally with the outer wing feathers (P9, P10), but no scientific studies have previously addressed this hypothesis. Although most birds that make non-vocal communication sounds have feathers with a shape distinctively modified for sound production, Smithornis broadbills do not. We investigated whether this song is produced vocally or with the wings in rufous-sided broadbill (S. rufolateralis) and African broad bill (S. capensis). In support of the wing song hypothesis, synchronized high-speed video and sound recordings of displays demonstrated that sound pulses were produced during the downstroke, subtle gaps sometimes appeared between the outer primary feathers P6-P10, and wing tip speed reached 16 m s(-1) Tests of a spread wing in a wind tunnel demonstrated that at a specific orientation, P6 and P7 flutter and produce sound. Wind tunnel tests on individual feathers P5-P10 from a male of each species revealed that while all of these feathers can produce sound via aeroelastic flutter, P6 and P7 produce the loudest sounds, which are similar in frequency to the wing song, at airspeeds achievable by the wing tip during display flight. Consistent with the wind tunnel experiments, field manipulations of P6, P7 and P8 changed the timbre of the wing song, and reduced its tonality, demonstrating that P6 and P7 are together the sound source, and not P9 or P10. The resultant wing song appears to have functionally replaced vocal song. PMID:27030781

  1. Morphology of galaxies in the WINGS clusters

    NASA Astrophysics Data System (ADS)

    Fasano, G.; Vanzella, E.; Dressler, A.; Poggianti, B. M.; Moles, M.; Bettoni, D.; Valentinuzzi, T.; Moretti, A.; D'Onofrio, M.; Varela, J.; Couch, W. J.; Kjærgaard, P.; Fritz, J.; Omizzolo, A.; Cava, A.

    2012-02-01

    We present the morphological catalogue of galaxies in nearby clusters of the WIde-field Nearby Galaxy-clusters Survey (WINGS). The catalogue contains a total number of 39 923 galaxies, for which we provide the automated estimates of the morphological type, applying the purposely devised tool MORPHOT to the V-band WINGS imaging. For ˜3000 galaxies we also provide visual estimates of the morphological type. A substantial part of the paper is devoted to the description of the MORPHOT tool, whose application is limited, at least for the moment, to the WINGS imaging only. The approach of the tool to the automation of morphological classification is a non-parametric and fully empirical one. In particular, MORPHOT exploits 21 morphological diagnostics, directly and easily computable from the galaxy image, to provide two independent classifications: one based on a maximum likelihood (ML), semi-analytical technique and the other one on a neural network (NN) machine. A suitably selected sample of ˜1000 visually classified WINGS galaxies is used to calibrate the diagnostics for the ML estimator and as a training set in the NN machine. The final morphological estimator combines the two techniques and proves to be effective both when applied to an additional test sample of ˜1000 visually classified WINGS galaxies and when compared with small samples of Sloan Digital Sky Survey (SDSS) galaxies visually classified by Fukugita et al. and Nair et al. Finally, besides the galaxy morphology distribution (corrected for field contamination) in the WINGS clusters, we present the ellipticity (ɛ), colour (B-V) and Sersic index (n) distributions for different morphological types, as well as the morphological fractions as a function of the clustercentric distance (in units of R200).

  2. Hybrid Wing Body Configuration System Studies

    NASA Technical Reports Server (NTRS)

    Nickol, Craig L.; McCullers, Arnie

    2009-01-01

    The objective of this study was to develop a hybrid wing body (HWB) sizing and analysis capability, apply that capability to estimate the fuel burn potential for an HWB concept, and identify associated technology requirements. An advanced tube with wings concept was also developed for comparison purposes. NASA s Flight Optimization System (FLOPS) conceptual aircraft sizing and synthesis software was modified to enable the sizing and analysis of HWB concepts. The noncircular pressurized centerbody of the HWB concept was modeled, and several options were created for defining the outboard wing sections. Weight and drag estimation routines were modified to accommodate the unique aspects of an HWB configuration. The resulting capability was then utilized to model a proprietary Boeing blended wing body (BWB) concept for comparison purposes. FLOPS predicted approximately a 15 percent greater drag, mainly caused by differences in compressibility drag estimation, and approximately a 5 percent greater takeoff gross weight, mainly caused by the additional fuel required, as compared with the Boeing data. Next, a 777-like reference vehicle was modeled in FLOPS and calibrated to published Boeing performance data; the same mission definition was used to size an HWB in FLOPS. Advanced airframe and propulsion technology assumptions were applied to the HWB to develop an estimate for potential fuel burn savings from such a concept. The same technology assumptions, where applicable, were then applied to an advanced tube-with-wings concept. The HWB concept had a 39 percent lower block fuel burn than the reference vehicle and a 12 percent lower block fuel burn than the advanced tube-with-wings configuration. However, this fuel burn advantage is partially derived from assuming the high-risk technology of embedded engines with boundary-layer-ingesting inlets. The HWB concept does have the potential for significantly reduced noise as a result of the shielding advantages that are inherent

  3. An Experimental Investigation on Flapping Flexible Membrane Wings

    NASA Astrophysics Data System (ADS)

    Hu, Hui; Abate, Gregg; Albertani, Roberto

    2008-11-01

    Thin and flexible membrane wings are unique to flying and gliding mammals, such as bats, flying squirrels and sugar gliders. These animals exhibit extraordinary flight capabilities with respect to maneuvering and agility that are not observed in other species of comparable size. In this study, comprehensive wind tunnel experiments are conducted to assess the effects of membrane flexibility (rigidity) on the aerodynamic performance of the flapping flexible membrane wings to quantify the benefits of using flexible membrane wings compared with conventional rigid wings for flapping-wing Micro-Air-Vehicle (MAV) applications. The present study is conducted from the viewpoint of aerospace engineers to try to leverage the unique feature of flexible membrane airfoils/wings found in bats and other flying/gliding mammals as an effective aerodynamic control method to explore the potential applications of such non-traditional, bio-inspired flexible membrane wings to flapping-wing MAVs to improve their flight agility and maneuverability.

  4. 11. VIEW OF SOUTHWEST CORNER OF SOUTH WING OF TECHWOOD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. VIEW OF SOUTHWEST CORNER OF SOUTH WING OF TECHWOOD DORMITORY. WEST FRONT OF SOUTH WING OBSCURED BY DEEP SHADE. - Techwood Homes, McDaniel Dormitory, 581-587 Techwood Drive, Atlanta, Fulton County, GA

  5. Wing flexibility enhances load-lifting capacity in bumblebees

    PubMed Central

    Mountcastle, Andrew M.; Combes, Stacey A.

    2013-01-01

    The effect of wing flexibility on aerodynamic force production has emerged as a central question in insect flight research. However, physical and computational models have yielded conflicting results regarding whether wing deformations enhance or diminish flight forces. By experimentally stiffening the wings of live bumblebees, we demonstrate that wing flexibility affects aerodynamic force production in a natural behavioural context. Bumblebee wings were artificially stiffened in vivo by applying a micro-splint to a single flexible vein joint, and the bees were subjected to load-lifting tests. Bees with stiffened wings showed an 8.6 per cent reduction in maximum vertical aerodynamic force production, which cannot be accounted for by changes in gross wing kinematics, as stroke amplitude and flapping frequency were unchanged. Our results reveal that flexible wing design and the resulting passive deformations enhance vertical force production and load-lifting capacity in bumblebees, locomotory traits with important ecological implications. PMID:23536604

  6. Lock 5 View west of wing walls and chamber ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Lock 5 - View west of wing walls and chamber with gate pockets visible. Note two small notches in brick at lower portion of wing walls - Savannah & Ogeechee Barge Canal, Between Ogeechee & Savannah Rivers, Savannah, Chatham County, GA

  7. View of intersection with west wall of north wing and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of intersection with west wall of north wing and north wall of west wing; camera facing southeast. - Mare Island Naval Shipyard, Marine Prison, Suisun Avenue, west side between Mesa Road & San Pablo, Vallejo, Solano County, CA

  8. Detail of northeast wing wall and guiderail. The section of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of northeast wing wall and guiderail. The section of the wing wall in the foreground is a historic extension of this element. - Chester County Bridge No. 225, Spanning Tweed Creek at Hopewell Road, Oxford, Chester County, PA

  9. The unsteady lift of a wing of finite aspect ratio

    NASA Technical Reports Server (NTRS)

    Jones, Robert T

    1940-01-01

    Unsteady-lift functions for wings of finite aspect ratio have been calculated by correcting the aerodynamic inertia and the angle of attack of the infinite wing. The calculations are based on the operational method.

  10. Wing flexibility enhances load-lifting capacity in bumblebees.

    PubMed

    Mountcastle, Andrew M; Combes, Stacey A

    2013-05-22

    The effect of wing flexibility on aerodynamic force production has emerged as a central question in insect flight research. However, physical and computational models have yielded conflicting results regarding whether wing deformations enhance or diminish flight forces. By experimentally stiffening the wings of live bumblebees, we demonstrate that wing flexibility affects aerodynamic force production in a natural behavioural context. Bumblebee wings were artificially stiffened in vivo by applying a micro-splint to a single flexible vein joint, and the bees were subjected to load-lifting tests. Bees with stiffened wings showed an 8.6 per cent reduction in maximum vertical aerodynamic force production, which cannot be accounted for by changes in gross wing kinematics, as stroke amplitude and flapping frequency were unchanged. Our results reveal that flexible wing design and the resulting passive deformations enhance vertical force production and load-lifting capacity in bumblebees, locomotory traits with important ecological implications. PMID:23536604

  11. 6. DETAIL OF MASONRY ON SOUTHWEST WING WALL. MASONRY ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL OF MASONRY ON SOUTHWEST WING WALL. MASONRY ON WING WALLS IS LAID IN A RANDOM RUBBLE PATTERN. - Core Creek County Bridge, Spanning Core Creek, approximately 1 mile South of State Route 332 (Newtown Bypass), Newtown, Bucks County, PA

  12. Physical Mechanisms of Glaze Ice Scallop Formations on Swept Wings

    NASA Technical Reports Server (NTRS)

    Vargas, Mario; Reshotko, Eli

    1998-01-01

    An experiment was conducted to understand the physical mechanisms that lead to the formation of scallops on swept wings. Icing runs were performed on a NACA 0012 swept wing tip at 45 deg, 30 deg, and 15 deg sweep angles. A baseline case was chosen and direct measurements of scallop height and spacing, castings, video data and close-up photographic data were obtained. The results showed the scallops are made of glaze ice feathers that grow from roughness elements that have reached a minimum height and are located beyond a given distance from the attachment line. This distance depends on tunnel conditions and sweep angle, and is the critical parameter in the formation of scallops. It determines if complete scallops, incomplete scallops or no scallops are going to be formed. The mechanisms of growth for complete and incomplete scallops were identified. The effect of velocity, temperature and LWC on scallop formation was studied. The possibility that cross flow instability may be the physical mechanism that triggers the growth of roughness elements into glaze ice feathers is examined.

  13. Dynamic response of a piezoelectric flapping wing

    NASA Astrophysics Data System (ADS)

    Kumar, Alok; Khandwekar, Gaurang; Venkatesh, S.; Mahapatra, D. R.; Dutta, S.

    2015-03-01

    Piezo-composite membranes have advantages over motorized flapping where frequencies are high and certain coupling between bending and twisting is useful to generate lift and forward flight. We draw examples of fruit fly and bumble bee. Wings with Piezo ceramic PZT coating are realized. The passive mechanical response of the wing is characterized experimentally and validated using finite element simulation. Piezoelectric actuation with uniform electrode coating is characterized and optimal frequencies for flapping are identified. The experimental data are used in an empirical model and advanced ratio for a flapping insect like condition for various angular orientations is estimated.

  14. Numerical simulation of swept-wing flows

    NASA Technical Reports Server (NTRS)

    Reed, Helen L.

    1991-01-01

    Efforts of the last six months to computationally model the transition process characteristics of flow over swept wings are described. Specifically, the crossflow instability and crossflow/Tollmien-Schlichting wave interactions are analyzed through the numerical solution of the full 3D Navier-Stokes equations including unsteadiness, curvature, and sweep. This approach is chosen because of the complexity of the problem and because it appears that linear stability theory is insufficient to explain the discrepancies between different experiments and between theory and experiment. The leading edge region of a swept wing is considered in a 3D spatial simulation with random disturbances as the initial conditions.

  15. Wing Leading Edge Concepts for Noise Reduction

    NASA Technical Reports Server (NTRS)

    Shmilovich, Arvin; Yadlin, Yoram; Pitera, David M.

    2010-01-01

    This study focuses on the development of wing leading edge concepts for noise reduction during high-lift operations, without compromising landing stall speeds, stall characteristics or cruise performance. High-lift geometries, which can be obtained by conventional mechanical systems or morphing structures have been considered. A systematic aerodynamic analysis procedure was used to arrive at several promising configurations. The aerodynamic design of new wing leading edge shapes is obtained from a robust Computational Fluid Dynamics procedure. Acoustic benefits are qualitatively established through the evaluation of the computed flow fields.

  16. The NYU inverse swept wing code

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Garabedian, P.; Mcfadden, G.

    1983-01-01

    An inverse swept wing code is described that is based on the widely used transonic flow program FLO22. The new code incorporates a free boundary algorithm permitting the pressure distribution to be prescribed over a portion of the wing surface. A special routine is included to calculate the wave drag, which can be minimized in its dependence on the pressure distribution. An alternate formulation of the boundary condition at infinity was introduced to enhance the speed and accuracy of the code. A FORTRAN listing of the code and a listing of a sample run are presented. There is also a user's manual as well as glossaries of input and output parameters.

  17. Wing download reduction using vortex trapping plates

    NASA Technical Reports Server (NTRS)

    Light, Jeffrey S.; Stremel, Paul M.; Bilanin, Alan J.

    1994-01-01

    A download reduction technique using spanwise plates on the upper and lower wing surfaces has been examined. Experimental and analytical techniques were used to determine the download reduction obtained using this technique. Simple two-dimensional wind tunnel testing confirmed the validity of the technique for reducing two-dimensional airfoil drag. Computations using a two-dimensional Navier-Stokes analysis provided insight into the mechanism causing the drag reduction. Finally, the download reduction technique was tested using a rotor and wing to determine the benefits for a semispan configuration representative of a tilt rotor aircraft.

  18. Eastward migration of blue-winged teal

    USGS Publications Warehouse

    Sharp, B.

    1972-01-01

    Of 3,789 recoveries of blue-winged teal (Anas discors) banded prior to the hunting season in the prairie pothole region, 183 (4.8 percent) were recovered, due east in New England, Ontario, Quebec, and the Maritime Provinces during the subsequent hunting season. Of 19 recoveries looked at in detail, all were banded as either hatching-year (flying young) or local (flightless young) birds. A blue-winged teal banded in Minnesota in September was retrapped in October in South Carolina, before being shot later that month in Colombia, South America.

  19. Algorithmic Identification for Wings in Butterfly Diagrams.

    NASA Astrophysics Data System (ADS)

    Illarionov, E. A.; Sokolov, D. D.

    2012-12-01

    We investigate to what extent the wings of solar butterfly diagrams can be separated without an explicit usage of Hale's polarity law as well as the location of the solar equator. Two algorithms of cluster analysis, namely DBSCAN and C-means, have demonstrated their ability to separate the wings of contemporary butterfly diagrams based on the sunspot group density in the diagram only. Here we generalize the method for continuous tracers, give results concerning the migration velocities and presented clusters for 12 - 20 cycles.

  20. Flutter analysis of low aspect ratio wings

    NASA Technical Reports Server (NTRS)

    Parnell, L. A.

    1986-01-01

    Several very low aspect ratio flat plate wing configurations are analyzed for their aerodynamic instability (flutter) characteristics. All of the wings investigated are delta planforms with clipped tips, made of aluminum alloy plate and cantilevered from the supporting vehicle body. Results of both subsonic and supersonic NASTRAN aeroelastic analyses as well as those from another version of the program implementing the supersonic linearized aerodynamic theory are presented. Results are selectively compared with the experimental data; however, supersonic predictions of the Mach Box method in NASTRAN are found to be erratic and erroneous, requiring the use of a separate program.

  1. Review of delta wing space shuttle vehicle dynamics

    NASA Technical Reports Server (NTRS)

    Reding, J. P.; Ericsson, L. E.

    1971-01-01

    The unsteady aerodynamics of the proposed delta planform, high cross range, shuttle orbiters, are investigated. It is found that these vehicles are subject to five unsteady-flow phenomena that could compromise the flight dynamics. The phenomena are as follows: (1) leeside shock-induced separation, (2) sudden leading-edge stall, (3) vortex burst, (4)bow shock-flap shock interaction, and (5) forebody vorticity. Trajectory shaping is seen as the most powerful means of avoiding deterimental effects of the stall phenomena; however, stall must be fixed or controlled when traversing the stall region. Other phenomana may be controlled by carefully programmed control deflections and some configuration modifications. Ways to alter the occurrence of the various flow conditions are explored.

  2. Methods for In-Flight Wing Shape Predictions of Highly Flexible Unmanned Aerial Vehicles: Formulation of Ko Displacement Theory

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Fleischer, Van Tran

    2010-01-01

    The Ko displacement theory is formulated for a cantilever tubular wing spar under bending, torsion, and combined bending and torsion loading. The Ko displacement equations are expressed in terms of strains measured at multiple sensing stations equally spaced on the surface of the wing spar. The bending and distortion strain data can then be input to the displacement equations to calculate slopes, deflections, and cross-sectional twist angles of the wing spar at the strain-sensing stations for generating the deformed shapes of flexible aircraft wing spars. The displacement equations have been successfully validated for accuracy by finite-element analysis. The Ko displacement theory that has been formulated could also be applied to calculate the deformed shape of simple and tapered beams, plates, and tapered cantilever wing boxes. The Ko displacement theory and associated strain-sensing system (such as fiber optic sensors) form a powerful tool for in-flight deformation monitoring of flexible wings and tails, such as those often employed on unmanned aerial vehicles. Ultimately, the calculated displacement data can be visually displayed in real time to the ground-based pilot for monitoring the deformed shape of unmanned aerial vehicles during flight.

  3. Spanwise transition section for blended wing-body aircraft

    NASA Technical Reports Server (NTRS)

    Hawley, Arthur V. (Inventor)

    1999-01-01

    A blended wing-body aircraft includes a central body, a wing, and a transition section which interconnects the body and the wing on each side of the aircraft. The two transition sections are identical, and each has a variable chord length and thickness which varies in proportion to the chord length. This enables the transition section to connect the thin wing to the thicker body. Each transition section has a negative sweep angle.

  4. Kinematic compensation for wing loss in flying damselflies.

    PubMed

    Kassner, Ziv; Dafni, Eyal; Ribak, Gal

    2016-02-01

    Flying insects can tolerate substantial wing wear before their ability to fly is entirely compromised. In order to keep flying with damaged wings, the entire flight apparatus needs to adjust its action to compensate for the reduced aerodynamic force and to balance the asymmetries in area and shape of the damaged wings. While several studies have shown that damaged wings change their flapping kinematics in response to partial loss of wing area, it is unclear how, in insects with four separate wings, the remaining three wings compensate for the loss of a fourth wing. We used high-speed video of flying blue-tailed damselflies (Ischnura elegans) to identify the wingbeat kinematics of the two wing pairs and compared it to the flapping kinematics after one of the hindwings was artificially removed. The insects remained capable of flying and precise maneuvering using only three wings. To compensate for the reduction in lift, they increased flapping frequency by 18±15.4% on average. To achieve steady straight flight, the remaining intact hindwing reduced its flapping amplitude while the forewings changed their stroke plane angle so that the forewing of the manipulated side flapped at a shallower stroke plane angle. In addition, the angular position of the stroke reversal points became asymmetrical. When the wingbeat amplitude and frequency of the three wings were used as input in a simple aerodynamic model, the estimation of total aerodynamic force was not significantly different (paired t-test, p=0.73) from the force produced by the four wings during normal flight. Thus, the removal of one wing resulted in adjustments of the motions of the remaining three wings, exemplifying the precision and plasticity of coordination between the operational wings. Such coordination is vital for precise maneuvering during normal flight but it also provides the means to maintain flight when some of the wings are severely damaged. PMID:26598807

  5. Titanium honeycomb structure. [for supersonic aircraft wing structure

    NASA Technical Reports Server (NTRS)

    Davis, R. A.; Elrod, S. D.; Lovell, D. T.

    1972-01-01

    A brazed titanium honeycomb sandwich system for supersonic transport wing cover panels provides the most efficient structure spanwise, chordwise, and loadwise. Flutter testing shows that high wing stiffness is most efficient in a sandwich structure. This structure also provides good thermal insulation if liquid fuel is carried in direct contact with the wing structure in integral fuel tanks.

  6. X-Wing Research Vehicle in Hangar

    NASA Technical Reports Server (NTRS)

    1987-01-01

    One of the most unusual experimental flight vehicles appearing at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center) in the 1980s was the Rotor Systems Research Aircraft (RSRA) X-Wing aircraft, seen here on the ramp. The craft was developed originally and then modified by Sikorsky Aircraft for a joint NASA-Defense Advanced Research Projects Agency (DARPA) program and was rolled out 19 August 1986. Taxi tests and initial low-altitude flight tests without the main rotor attached were carried out at Dryden before the program was terminated in 1988. The unusual aircraft that resulted from the Ames Research Center/Army X-Wing Project was flown at the Ames-Dryden Flight Research Facility (now Dryden Flight Research Center), Edwards, California, beginning in the spring of 1984, with a follow-on program beginning in 1986. The program, was conceived to provide an efficient combination of the vertical lift characteristic of conventional helicopters and the high cruise speed of fixed-wing aircraft. It consisted of a hybrid vehicle called the NASA/Army Rotor Systems Research Aircraft (RSRA), which was equipped with advanced X-wing rotor systems. The program began in the early 1970s to investigate ways to increase the speed of rotor aircraft, as well as their performance, reliability, and safety . It also sought to reduce the noise, vibration, and maintenance costs of helicopters. Sikorsky Aircraft Division of United Technologies Laboratories built two RSRA aircraft. NASA's Langley Research Center, Hampton, Virginia, did some initial testing and transferred the program to Ames Research Center, Mountain View, California, for an extensive flight research program conducted by Ames and the Army. The purpose of the 1984 tests was to demonstrate the fixed-wing capability of the helicopter/airplane hybrid research vehicle and explore its flight envelope and flying qualities. These tests, flown by Ames pilot G. Warren Hall and Army Maj (soon

  7. A study of the effects of aeroelastic divergence on the wing structure of an oblique-wing supersonic transport configuration

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The aerodynamic characteristics of transport aircraft with oblique wing flying at supersonic speeds are discussed. Aeroelastic divergence of the forward swept portion of the wing is analyzed. The effect of aspect ratio as a method for avoiding aeroelastic divergence is examined. A relatively low aspect ratio appears necessary for an oblique wing when constructed of conventional aluminum alloy materials. The aspect ratio may be increased by increasing the wing thickness ratio and by utilizing materials with higher moduli of elasticity and rigidity.

  8. Computational wing optimization and comparisons with experiment for a semi-span wing model

    NASA Technical Reports Server (NTRS)

    Waggoner, E. G.; Haney, H. P.; Ballhaus, W. F.

    1978-01-01

    A computational wing optimization procedure was developed and verified by an experimental investigation of a semi-span variable camber wing model in the NASA Ames Research Center 14 foot transonic wind tunnel. The Bailey-Ballhaus transonic potential flow analysis and Woodward-Carmichael linear theory codes were linked to Vanderplaats constrained minimization routine to optimize model configurations at several subsonic and transonic design points. The 35 deg swept wing is characterized by multi-segmented leading and trailing edge flaps whose hinge lines are swept relative to the leading and trailing edges of the wing. By varying deflection angles of the flap segments, camber and twist distribution can be optimized for different design conditions. Results indicate that numerical optimization can be both an effective and efficient design tool. The optimized configurations had as good or better lift to drag ratios at the design points as the best designs previously tested during an extensive parametric study.

  9. Unsteady aerodynamics of dragonfly using a wing-wing model from the perspective of a force decomposition

    NASA Astrophysics Data System (ADS)

    Chu, Chin-Chou; Chang, Chien C.; Hsieh, Chen-Ta

    2009-11-01

    The lift and thrust associated with insect flight strongly depend on the complex wake patterns produced by wing-wing and wing-wake interactions. We propose to investigate the aerodynamics of dragonfly using a simplified wing-wing model from the perspective of many-body force decomposition (JFM 600, p95) and the associated force elements. The aerodynamic force, lift or thrust, of the wing-wing system is analyzed in terms of its four constituent components, each of which is directly related to a physical effect. These force components for each individual wing include two potential contributions credited to the wing motion itself, contribution from the vorticity within the flow, and contributions from the surface vorticity on its and other wing's surfaces. The potential contribution due to added-mass effect is often non-negligible. Nevertheless, the major contribution to the forces comes from the vorticity within the flow. The relative importance of these components relies heavily on the motions of the two wings such as the respective angles of attack, the amplitude and speed of translational motions, and the amplitude and speed of wing rotations. In addition to the dynamic stall vortex, several important mechanisms of high lift or thrust are also identified.

  10. General Potential Theory of Arbitrary Wing Section

    NASA Technical Reports Server (NTRS)

    Theodorsen, T; Garrick, I E

    1934-01-01

    This report gives the exact treatment of the problem of determining the 2-dimensional potential flow around wing sections of any type. The treatment is based directly on the solution of this problem as advanced by Theodorsen in NACA-TR-411. The problem condenses into the compact form of an integral equation capable of yielding numerical solutions by a direct process.

  11. Bat wing sensors support flight control

    PubMed Central

    Sterbing-D'Angelo, Susanne; Chadha, Mohit; Chiu, Chen; Falk, Ben; Xian, Wei; Barcelo, Janna; Zook, John M.; Moss, Cynthia F.

    2011-01-01

    Bats are the only mammals capable of powered flight, and they perform impressive aerial maneuvers like tight turns, hovering, and perching upside down. The bat wing contains five digits, and its specialized membrane is covered with stiff, microscopically small, domed hairs. We provide here unique empirical evidence that the tactile receptors associated with these hairs are involved in sensorimotor flight control by providing aerodynamic feedback. We found that neurons in bat primary somatosensory cortex respond with directional sensitivity to stimulation of the wing hairs with low-speed airflow. Wing hairs mostly preferred reversed airflow, which occurs under flight conditions when the airflow separates and vortices form. This finding suggests that the hairs act as an array of sensors to monitor flight speed and/or airflow conditions that indicate stall. Depilation of different functional regions of the bats’ wing membrane altered the flight behavior in obstacle avoidance tasks by reducing aerial maneuverability, as indicated by decreased turning angles and increased flight speed. PMID:21690408

  12. Applications of a transonic wing design method

    NASA Technical Reports Server (NTRS)

    Campbell, Richard L.; Smith, Leigh A.

    1989-01-01

    A method for designing wings and airfoils at transonic speeds using a predictor/corrector approach was developed. The procedure iterates between an aerodynamic code, which predicts the flow about a given geometry, and the design module, which compares the calculated and target pressure distributions and modifies the geometry using an algorithm that relates differences in pressure to a change in surface curvature. The modular nature of the design method makes it relatively simple to couple it to any analysis method. The iterative approach allows the design process and aerodynamic analysis to converge in parallel, significantly reducing the time required to reach a final design. Viscous and static aeroelastic effects can also be accounted for during the design or as a post-design correction. Results from several pilot design codes indicated that the method accurately reproduced pressure distributions as well as the coordinates of a given airfoil or wing by modifying an initial contour. The codes were applied to supercritical as well as conventional airfoils, forward- and aft-swept transport wings, and moderate-to-highly swept fighter wings. The design method was found to be robust and efficient, even for cases having fairly strong shocks.

  13. The Right-Wing Attack on Women.

    ERIC Educational Resources Information Center

    Fishman, Walda Katz

    A personal evaluation is expressed on the changing role of women in the United States as a result of current social attitudes and of recent legislation regarding medical, economic, and educational matters. It is hypothesized that the United States is currently experiencing an extreme and growing right-wing political movement whose targets include…

  14. Permian insect wing from antarctic sentinel mountains.

    PubMed

    Tasch, P; Riek, E F

    1969-06-27

    A homopterous insect wing was found in micaceous graywacke from the Polarstar Formation, Sentinel Mountains. The unusual venation is reminiscent of family Stenoviciidae known from the Permian and Triassic of Eastern Australia and elsewhere. This first documented account of Paleozoic insects in Antarctica bears on drift questions. PMID:17748532

  15. Reconfiguration control system for an aircraft wing

    NASA Technical Reports Server (NTRS)

    Wakayama, Sean R. (Inventor)

    2008-01-01

    Independently deflectable control surfaces are located on the trailing edge of the wing of a blended wing-body aircraft. The reconfiguration control system of the present invention controls the deflection of each control surface to optimize the spanwise lift distribution across the wing for each of several flight conditions, e.g., cruise, pitch maneuver, and high lift at low speed. The control surfaces are deflected and reconfigured to their predetermined optimal positions when the aircraft is in each of the aforementioned flight conditions. With respect to cruise, the reconfiguration control system will maximize the lift to drag ratio and keep the aircraft trimmed at a stable angle of attack. In a pitch maneuver, the control surfaces are deflected to pitch the aircraft and increase lift. Moreover, this increased lift has its spanwise center of pressure shifted inboard relative to its location for cruise. This inboard shifting reduces the increased bending moment about the aircraft's x-axis occasioned by the increased pitch force acting normal to the wing. To optimize high lift at low speed, during take-off and landing for example, the control surfaces are reconfigured to increase the local maximum coefficient of lift at stall-critical spanwise locations while providing pitch trim with control surfaces that are not stall critical.

  16. Hybrid Wing Body Configuration Scaling Study

    NASA Technical Reports Server (NTRS)

    Nickol, Craig L.

    2012-01-01

    The Hybrid Wing Body (HWB) configuration is a subsonic transport aircraft concept with the potential to simultaneously reduce fuel burn, noise and emissions compared to conventional concepts. Initial studies focused on very large applications with capacities for up to 800 passengers. More recent studies have focused on the large, twin-aisle class with passenger capacities in the 300-450 range. Efficiently scaling this concept down to the single aisle or smaller size is challenging due to geometric constraints, potentially reducing the desirability of this concept for applications in the 100-200 passenger capacity range or less. In order to quantify this scaling challenge, five advanced conventional (tube-and-wing layout) concepts were developed, along with equivalent (payload/range/technology) HWB concepts, and their fuel burn performance compared. The comparison showed that the HWB concepts have fuel burn advantages over advanced tube-and-wing concepts in the larger payload/range classes (roughly 767-sized and larger). Although noise performance was not quantified in this study, the HWB concept has distinct noise advantages over the conventional tube-and-wing configuration due to the inherent noise shielding features of the HWB. NASA s Environmentally Responsible Aviation (ERA) project will continue to investigate advanced configurations, such as the HWB, due to their potential to simultaneously reduce fuel burn, noise and emissions.

  17. Fiber-optically sensorized composite wing

    NASA Astrophysics Data System (ADS)

    Costa, Joannes M.; Black, Richard J.; Moslehi, Behzad; Oblea, Levy; Patel, Rona; Sotoudeh, Vahid; Abouzeida, Essam; Quinones, Vladimir; Gowayed, Yasser; Soobramaney, Paul; Flowers, George

    2014-04-01

    Electromagnetic interference (EMI) immune and light-weight, fiber-optic sensor based Structural Health Monitoring (SHM) will find increasing application in aerospace structures ranging from aircraft wings to jet engine vanes. Intelligent Fiber Optic Systems Corporation (IFOS) has been developing multi-functional fiber Bragg grating (FBG) sensor systems including parallel processing FBG interrogators combined with advanced signal processing for SHM, structural state sensing and load monitoring applications. This paper reports work with Auburn University on embedding and testing FBG sensor arrays in a quarter scale model of a T38 composite wing. The wing was designed and manufactured using fabric reinforced polymer matrix composites. FBG sensors were embedded under the top layer of the composite. Their positions were chosen based on strain maps determined by finite element analysis. Static and dynamic testing confirmed expected response from the FBGs. The demonstrated technology has the potential to be further developed into an autonomous onboard system to perform load monitoring, SHM and Non-Destructive Evaluation (NDE) of composite aerospace structures (wings and rotorcraft blades). This platform technology could also be applied to flight testing of morphing and aero-elastic control surfaces.

  18. Space Shuttle: The Renewed Promise

    NASA Technical Reports Server (NTRS)

    McAleer, Neil

    1989-01-01

    NASA celebrated its 30th anniversary in 1988, two days after the Space Shuttle soared into space once more. When Congress approved the creation of the National Aeronautics and Space Administration in 1958, the United States had successfully launched only four small satellites and no American astronaut had yet flown in space. In the three decades since, four generations of manned spacecraft have been built and flown, twelve men have walked on the Moon, more than 100 Americans have flown and worked in space, and communications satellites and other Space-Age technologies have transformed life on planet Earth. When NASA's Golden Anniversary is celebrated in 2008, it is likely that men and women will be permanently living and working in space. There may be a base on the Moon, and a manned mission to Mars may only be years away. If a brief history of the first half-century of the Space Age is written for that event, it will show clearly how the exploration of space has altered the course of human history and allowed us to take a better hold of our destiny on and off planet Earth.

  19. Elements of the Wing Section Theory and of the Wing Theory

    NASA Technical Reports Server (NTRS)

    Munk, Max M

    1925-01-01

    This report contains those results of the theory of wings and of wing sections which are of immediate practical value. They are proved and demonstrated by the use of the simple conceptions of "kinetic energy" and "momentum" only, familiar to every engineer; and not by introducing "isogonal transformations" and "vortices," which latter mathematical methods are not essential to the theory and better are used only in papers intended for mathematicians and special experts.

  20. Simulation of transonic viscous wing and wing-fuselage flows using zonal methods

    NASA Technical Reports Server (NTRS)

    Flores, Jolen

    1987-01-01

    The thin-layer Navier-Stokes equations are coupled with a zonal scheme (or domain-decomposition method) to develop the Transonic Navier-Stokes (TNS) wing-alone code. The TNS has a total of 4 zones and is extended to a total of 16 zones for the wing-fuselage version of the code. Results are compared on the Cray X-MP-48 and compared with experimental data.

  1. Apex wing section undergoing loading test

    NASA Technical Reports Server (NTRS)

    1998-01-01

    STRESS TEST -- A test section of a wing being developed for the Apex high-altitude research project is being subjected to simulated air loads similar to what it will encounter in flight during tests at Dryden's Flight Loads Laboratory. The current tests on a fiberglass test wing are developing test methods to be used during future ultimate loads tests that will apply loads of 150 percent or greater on another test section until it fails. That section is being built from the actual materials to be used in the Apex flight wing, an all-composite structure which features a stiff, lightweight boron fiber skin covering a foam and graphite cloth core. It is designed for flight loads of 5 Gs (five times the force of gravity) positive and 3 Gs negative. The Apex project, part of NASA's Revolutionary Concepts (RevCon) effort, will use a highly-modified commercial sailplane design to acquire data on the aerodynamics of flight in the previously unexplored regime of 70,000 to 100,000 feet altitude and subsonic speeds of about Mach 0.65. The Apex High-Altitude Flight Experiment is expected to explore the aerodynamics of controlled flight at very high altitudes near 100,000 feet. The Apex will be hoisted aloft tail-first from Dryden by a large high-altitude balloon and released at about 110,000-feet altitude. As it gradually descends, its instrumentation will collect aerodynamic data. The remotely-piloted, semi-autonomous Apex will combine a modified ASC sailplane fuselage design with a new wing designed at the Massachusetts Institute of Technology. The wing will have a special airfoil designed for high subsonic speeds at extreme altitudes. A device extending behind the right wing is a 'wake rake,' which will measure aerodynamic drag behind a test section of the wing, while a rocket pack mounted beneath the fuselage will assist the Apex in transitioning to horizontal flight. Research flights were expected to begin in mid-1998, but a series of technical problems delayed them. In

  2. Blue-winged teals swim in shallow water

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A pair of blue-winged teals glide through the waters of the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Inhabiting marshes, shallow ponds and lakes from British Columbia, Quebec and Newfoundland to North Carolina, the Gulf Coast and southern California, the teal winters as far south as South America. The 92,000-acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

  3. Structural efficiency study of composite wing rib structures

    NASA Technical Reports Server (NTRS)

    Swanson, Gary D.; Gurdal, Zafer; Starnes, James H., Jr.

    1988-01-01

    A series of short stiffened panel designs which may be applied to a preliminary design assessment of an aircraft wing rib is presented. The computer program PASCO is used as the primary design and analysis tool to assess the structural efficiency and geometry of a tailored corrugated panel, a corrugated panel with a continuous laminate, a hat stiffened panel, a blade stiffened panel, and an unstiffened flat plate. To correct some of the shortcomings in the PASCO analysis when shear is present, a two step iterative process using the computer program VICON is used. The loadings considered include combinations of axial compression, shear, and lateral pressure. The loading ranges considered are broad enough such that the designs presented may be applied to other stiffened panel applications. An assessment is made of laminate variations, increased spacing, and nonoptimum geometric variations, including a beaded panel, on the design of the panels.

  4. Development of aerodynamic prediction methods for irregular planform wings

    NASA Technical Reports Server (NTRS)

    Benepe, D. B., Sr.

    1983-01-01

    A set of empirical methods was developed to predict low-speed lift, drag and pitching-moment variations with angle of attack for a class of low aspect ratio irregular planform wings suitable for application to advanced aerospace vehicles. The data base, an extensive series of wind-tunnel tests accomplished by the Langley Research Center of the National Aeronautics and Space Administration, is summarized. The approaches used to analyze the wind tunnel data, the evaluation of previously existing methods, data correlation efforts, and the development of the selected methods are presented and discussed. A summary of the methods is also presented to document the equations, computational charts and design guides which have been programmed for digital computer solution. Comparisons of predictions and test data are presented which show that the new methods provide a significant improvement in capability for evaluating the landing characteristics of advanced aerospace vehicles during the preliminary design phase of the configuration development cycle.

  5. Heat pipes for wing leading edges of hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Boman, B. L.; Citrin, K. M.; Garner, E. C.; Stone, J. E.

    1990-01-01

    Wing leading edge heat pipes were conceptually designed for three types of vehicle: an entry research vehicle, aero-space plane, and advanced shuttle. A full scale, internally instrumented sodium/Hastelloy X heat pipe was successfully designed and fabricated for the advanced shuttle application. The 69.4 inch long heat pipe reduces peak leading edge temperatures from 3500 F to 1800 F. It is internally instrumented with thermocouples and pressure transducers to measure sodium vapor qualities. Large thermal gradients and consequently large thermal stresses, which have the potential of limiting heat pipe life, were predicted to occur during startup. A test stand and test plan were developed for subsequent testing of this heat pipe. Heat pipe manufacturing technology was advanced during this program, including the development of an innovative technique for wick installation.

  6. Flexible Plug Repair for Shuttle Wing Leading Edge

    NASA Technical Reports Server (NTRS)

    Camarda, Charles J.; Sikora, Joseph; Smith, Russel; Rivers, H.; Scotti, Stephen J.; Fuller, Alan M.; Klacka, Robert; Reinders, Martin; Schwind, Francis; Sullivan, Brian; Lester, Dean

    2012-01-01

    In response to the Columbia Accident Investigation Board report, a plug repair kit has been developed to enable astronauts to repair the space shuttle's wing leading edge (WLE) during orbit. The plug repair kit consists of several 17.78- cm-diameter carbon/silicon carbide (C/SiC) cover plates of various curvatures that can be attached to the refractory carbon-carbon WLE panels using a TZM refractory metal attach mechanism. The attach mechanism is inserted through the damage in the WLE panel and, as it is tightened, the cover plate flexes to conform to the curvature of the WLE panel within 0.050 mm. An astronaut installs the repair during an extravehicular activity (EVA). After installing the plug repair, edge gaps are checked and the perimeter of the repair is sealed using a proprietary material, developed to fill cracks and small holes in the WLE.

  7. Forebody vortex control for suppressing wing rock on a highly-swept wing configuration

    NASA Technical Reports Server (NTRS)

    Suarez, Carlos J.; Kramer, Brian R.; Ayers, Bert; Malcolm, Gerald N.

    1992-01-01

    Free-to-roll tests were conducted in a wind tunnel with a configuration that consisted of a highly-slender forebody and a 78 deg swept delta wing. A limit cycle oscillation was observed for angles of attack between 22 and 30 deg. In general, the main flow phenomena responsible for the wing-body-tail wing rock are the interactions between the forebody and the wing vortices. Various blowing techniques were evaluated as means of wing rock suppression. Blowing tangentially aft from leeward side nozzles near the forebody tip can damp the roll motion at low blowing rates and stop it completely at higher blowing rates. At the high rates, significant vortex asymmetries are created, causing the model to stop at a non-zero roll angle. Forward blowing and alternating right/left pulsed blowing appear to be more efficient techniques for suppressing wing rock. The oscillations can be damped almost completely at lower blowing coefficients, and, apparently, no major vortex asymmetries are induced. Good agreement is observed between this study and previous water tunnel tests on the same configuration.

  8. Aerodynamic performance of a wing with a deflected tip-mounted reverse half-delta wing

    NASA Astrophysics Data System (ADS)

    Lee, T.; Su, Y. Y.

    2012-11-01

    The impact of a tip-mounted 65°-sweep reverse half-delta wing (RHDW), set at different deflections, on the aerodynamic performance of a rectangular NACA 0012 wing was investigated experimentally at Re = 2.45 × 105. This study is a continuation of the work of Lee and Su (Exp Fluids 52(6):1593-1609, 2012) on the passive control of wing tip vortex by the use of a reverse half-delta wing. The present results show that for RHDW deflection with -5° ≤ δ ≤ +15°, the lift was found to increase nonlinearly with increasing δ compared to the baseline wing. The lift increment was accompanied by an increased total drag. For negative RHDW deflection with δ < -5°, the RHDW-induced lift decrement was, however, accompanied by an improved drag. The deflected RHDW also significantly modified and weakened the tip vortex, leading to a persistently lowered lift-induced drag, regardless of its deflection, compared to the baseline wing. Physical mechanisms responsible for the observed RHDW-induced phenomenon were also discussed.

  9. Space shuttle phase B wind tunnel test database

    NASA Technical Reports Server (NTRS)

    Glynn, J. L.; Poucher, D. E.

    1988-01-01

    Archived wind tunnel test data are available for flyback booster or other alternate recoverable configurations as well as reusable orbiters studied during initial development (Phase B) of the Space Shuttle. Considerable wind tunnel data were acquired by competing contractors and NASA centers for an extensive variety of configurations with an array of wing and body planforms. This wind tunnel test data has been compiled into a database and are available for application to current winged flyback or recoverable booster aerodynamic studies. The Space Shuttle Phase B Wind Tunnel Database is structured by vehicle component and configuration type. Basic components include the booster, the orbiter and the launch vehicle. Booster configuration types include straight and delta wings, canard, cylindrical, retro-glide and twin body. Orbiter configuration types include straight and delta wings, lifting body, drop tanks and double delta wings.

  10. The Wing Apparatus and Flapping Behavior of Hymenoptera

    NASA Astrophysics Data System (ADS)

    Sudo, Seiichi; Tsuyuki, Koji; Ito, Yoshiyasu; Tani, Junji

    The wing apparatus of Hymenoptera was observed with a scanning electron microscope, and the structure and function of insect wings were studied. The measurements of displacement of extrinsic skeleton vibration produced by wing flapping of a wasp were made by an optical displacement detector system. The free flight of the wasp was analyzed by a three dimensional motion analysis system. The results of a series of measurements revealed the flight characteristics of Hymenoptera, such as the wing tip velocity, wing path, wave form of extrinsic skeleton vibration, and so forth.

  11. Steady-State Solution of a Flexible Wing

    NASA Technical Reports Server (NTRS)

    Karkehabadi, Reza; Chandra, Suresh; Krishnamurthy, Ramesh

    1997-01-01

    A fluid-structure interaction code, ENSAERO, has been used to compute the aerodynamic loads on a swept-tapered wing. The code has the capability of using Euler or Navier-Stokes equations. Both options have been used and compared in the present paper. In the calculation of the steady-state solution, we are interested in knowing how the flexibility of the wing influences the lift coefficients. If the results of a flexible wing are not affected by the flexibility of the wing significantly, one could consider the wing to be rigid and reduce the problem from fluid-structure interaction to a fluid problem.

  12. Aerodynamics on a transport aircraft type wing-body model

    NASA Technical Reports Server (NTRS)

    Schmitt, V.

    1982-01-01

    The DFLR-F4 wing-body combination is studied. The 1/38 model is formed by a 9.5 aspect ratio transonic wing and an Airbus A 310 fuselage. The F4 wing geometrical characteristics are described and the main experimental results obtained in the S2MA wind tunnel are discussed. Both wing-fuselage interferences and viscous effects, which are important on the wing due to a high rear loading, are investigated by performing 3D calculations. An attempt is made to find their limitations.

  13. NASA F-8A Crusader Supercritical Wing Aircraft

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A Vought F-8A Crusader was selected by NASA as the testbed aircraft (designated TF-8A) to install an experimental Supercritical Wing in place of the conventional wing. The unique design of the Supercritical Wing reduces the effect of shock waves on the upper surface near Mach 1, which in turn reduces drag. In this photograph a Vought F-8A Crusader is shown being used as a flying testbed for an experimental Supercritical Wing airfoil. The smooth fairing of the fiberglass glove with the wing is illustrated in this view.

  14. Aircraft energy efficiency laminar flow control wing design study

    NASA Technical Reports Server (NTRS)

    Bonner, T. F., Jr.; Pride, J. D., Jr.; Fernald, W. W.

    1977-01-01

    An engineering design study was performed in which laminar flow control (LFC) was integrated into the wing of a commercial passenger transport aircraft. A baseline aircraft configuration was selected and the wing geometry was defined. The LFC system, with suction slots, ducting, and suction pumps was integrated with the wing structure. The use of standard aluminum technology and advanced superplastic formed diffusion bonded titanium technology was evaluated. The results of the design study show that the LFC system can be integrated with the wing structure to provide a structurally and aerodynamically efficient wing for a commercial transport aircraft.

  15. Resonance of flexible flapping wings at low Reynolds number

    NASA Astrophysics Data System (ADS)

    Masoud, Hassan; Alexeev, Alexander

    2010-05-01

    Using three-dimensional computer simulations, we examine hovering aerodynamics of flexible planar wings oscillating at resonance. We model flexible wings as tilted elastic plates whose sinusoidal plunging motion is imposed at the plate root. Our simulations reveal that large-amplitude resonance oscillations of elastic wings drastically enhance aerodynamic lift and efficiency of low-Reynolds-number plunging. Driven by a simple sinusoidal stroke, flexible wings at resonance generate a hovering force comparable to that of small insects that employ a very efficient but much more complicated stroke kinematics. Our results indicate the feasibility of using flexible wings driven by a simple harmonic stroke for designing efficient microscale flying machines.

  16. Aeroelastic modeling of the active flexible wing wind-tunnel model

    NASA Technical Reports Server (NTRS)

    Silva, Walter A.; Heeg, Jennifer; Bennett, Robert M.

    1991-01-01

    The primary issues involved in the generation of linear, state-space equations of motion of a flexible wind tunnel model, the Active Flexible Wing (AFW), are discussed. The codes that were used and their inherent assumptions and limitations are also briefly discussed. The application of the CAP-TSD code to the AFW for determination of the model's transonic flutter boundary is included as well.

  17. Transonic aerodynamic characteristics of a proposed wing-body reusable launch vehicle concept

    NASA Technical Reports Server (NTRS)

    Springer, A. M.

    1995-01-01

    A proposed wing-body reusable launch vehicle was tested in the NASA Marshall Space Flight Center's 14 x 14-inch trisonic wind tunnel during the winter of 1994. This test resulted in the vehicle's subsonic and transonic, Mach 0.3 to 1.96, longitudinal and lateral aerodynamic characteristics. The effects of control surface deflections on the basic vehicle's aerodynamics, including a body flap, elevons, ailerons, and tip fins, are presented.

  18. Fracture Mechanics Analyses of the Slip-Side Joggle Regions of Wing-Leading-Edge Panels

    NASA Technical Reports Server (NTRS)

    Raju, Ivatury S.; Knight, Norman F., Jr.; Song, Kyongchan; Phillips, Dawn R.

    2011-01-01

    The Space Shuttle wing-leading edge consists of panels that are made of reinforced carbon-carbon. Coating spallation was observed near the slip-side region of the panels that experience extreme heating. To understand this phenomenon, a root-cause investigation was conducted. As part of that investigation, fracture mechanics analyses of the slip-side joggle regions of the hot panels were conducted. This paper presents an overview of the fracture mechanics analyses.

  19. Multiple Cues for Winged Morph Production in an Aphid Metacommunity

    PubMed Central

    Mehrparvar, Mohsen; Zytynska, Sharon E.; Weisser, Wolfgang W.

    2013-01-01

    Environmental factors can lead individuals down different developmental pathways giving rise to distinct phenotypes (phenotypic plasticity). The production of winged or unwinged morphs in aphids is an example of two alternative developmental pathways. Dispersal is paramount in aphids that often have a metapopulation structure, where local subpopulations frequently go extinct, such as the specialized aphids on tansy (Tanacetum vulgare). We conducted various experiments to further understand the cues involved in the production of winged dispersal morphs by the two dominant species of the tansy aphid metacommunity, Metopeurum fuscoviride and Macrosiphoniella tanacetaria. We found that the ant-tended M. fuscoviride produced winged individuals predominantly at the beginning of the season while the untended M. tanacetaria produced winged individuals throughout the season. Winged mothers of both species produced winged offspring, although in both species winged offspring were mainly produced by unwinged females. Crowding and the presence of predators, effects already known to influence wing production in other aphid species, increased the percentage of winged offspring in M. tanacetaria, but not in M. fuscoviride. We find there are also other factors (i.e. temporal effects) inducing the production of winged offspring for natural aphid populations. Our results show that the responses of each aphid species are due to multiple wing induction cues. PMID:23472179

  20. On the natural frequencies and mode shapes of dragonfly wings

    NASA Astrophysics Data System (ADS)

    Chen, Jen-San; Chen, Jeng-Yu; Chou, Yuan-Fang

    2008-06-01

    A base-excitation modal testing technique is adopted to measure the natural frequencies and mode shapes of dragonfly wings severed from thoraxes. The severed wings are glued onto the base of a shaker, which is capable of inducing translational motion in the lateral direction of the wing plane. Photonic probes are used to measure the displacement history of the shaker base and the painted spots of the wing simultaneously. A spectrum analyzer is employed to calculate the frequency response functions, from which the natural frequencies and the associated mode shapes of the wing structure can be extracted. Our experimental results show that the fundamental natural frequency of dragonfly wings is in the order of 170 Hz when it is clamped at the wing base. The average flapping frequency 27 Hz of dragonflies is about 16% of the fundamental natural frequency. At this frequency ratio, the inertial force of the wing is negligible compared to the elastic force. In other words, the wing deformation during flapping flight is solely due to the balance between the external aerodynamic force and the elastic force of the wing structure. The wing structures are generally lightly damped, with damping ratio in the order less than 5%.

  1. Wing Flexion and Aerodynamics Performance of Insect Free Flights

    NASA Astrophysics Data System (ADS)

    Dong, Haibo; Liang, Zongxian; Ren, Yan

    2010-11-01

    Wing flexion in flapping flight is a hallmark of insect flight. It is widely thought that wing flexibility and wing deformation would potentially provide new aerodynamic mechanisms of aerodynamic force productions over completely rigid wings. However, there are lack of literatures on studying fluid dynamics of freely flying insects due to the presence of complex shaped moving boundaries in the flow domain. In this work, a computational study of freely flying insects is being conducted. High resolution, high speed videos of freely flying dragonflies and damselflies is obtained and used as a basis for developing high fidelity geometrical models of the dragonfly body and wings. 3D surface reconstruction technologies are used to obtain wing topologies and kinematics. The wing motions are highly complex and a number of different strategies including singular vector decomposition of the wing kinematics are used to examine the various kinematical features and their impact on the wing performance. Simulations are carried out to examine the aerodynamic performance of all four wings and understand the wake structures of such wings.

  2. Large capacity oblique all-wing transport aircraft

    NASA Technical Reports Server (NTRS)

    Galloway, Thomas L.; Phillips, James A.; Kennelly, Robert A., Jr.; Waters, Mark H.

    1996-01-01

    Dr. R. T. Jones first developed the theory for oblique wing aircraft in 1952, and in subsequent years numerous analytical and experimental projects conducted at NASA Ames and elsewhere have established that the Jones' oblique wing theory is correct. Until the late 1980's all proposed oblique wing configurations were wing/body aircraft with the wing mounted on a pivot. With the emerging requirement for commercial transports with very large payloads, 450-800 passengers, Jones proposed a supersonic oblique flying wing in 1988. For such an aircraft all payload, fuel, and systems are carried within the wing, and the wing is designed with a variable sweep to maintain a fixed subsonic normal Mach number. Engines and vertical tails are mounted on pivots supported from the primary structure of the wing. The oblique flying wing transport has come to be known as the Oblique All-Wing (OAW) transport. This presentation gives the highlights of the OAW project that was to study the total concept of the OAW as a commercial transport.

  3. Survival of the fastest: Evolving wings for flapping flight

    NASA Astrophysics Data System (ADS)

    Ramananarivo, Sophie; Mitchel, Thomas; Ristroph, Leif

    2014-11-01

    To optimize flapping flight with regard to wing shape, we use an evolutionary or genetic algorithm to improve the forward speed of 3d-printed wings or hydrofoils that heave up-and-down and self-propel within water. In this scheme, ``genes'' are mathematical parameters specifying wing shape, and ``breeding'' involves the merging and mutation of genes from two parent wings to form a child. A wing's swimming speed is its ``fitness'', which dictates the likelihood of breeding and thus passing on its genes to the next generation. We find that this iterative process leads to marked improvements in relatively few generations, and several distinct shape features are shared among the fastest wings. We also investigate the favorable flow structures produced by these elite swimmers and compare their shape and performance to biologically evolved wings, fins, tails, and flippers.

  4. Volumetric visualization of the near- and far-field wake in flapping wings.

    PubMed

    Liu, Yun; Cheng, Bo; Barbera, Giovanni; Troolin, Daniel R; Deng, Xinyan

    2013-09-01

    The flapping wings of flying animals create complex vortex wake structure; understanding its spatial and temporal distribution is fundamental to animal flight theory. In this study, we applied the volumetric 3-component velocimetry to capture both the near- and far-field flow generated by a pair of mechanical flapping wings. For the first time, the complete three-dimensional wake structure and its evolution throughout a wing stroke were quantified and presented experimentally. The general vortex wake structure maintains a quite consistent form: vortex rings in the near field and two shear layers in the far field. Vortex rings shed periodically from the wings and are linked to each other in successive strokes. In the far field, the shed vortex rings evolve into two parallel shear layers with dominant vorticity convected from tip and root vortices. The shear layers are nearly stationary in space compared to the periodic vortex rings shed in the near field. In addition, downwash passes through the centers of the vortex rings and extends downward between the two shear layers. PMID:23924871

  5. Polymer based flapping-wing robotic insect: Progress in design, fabrication, and characterization

    NASA Astrophysics Data System (ADS)

    Bontemps, A.; Vanneste, T.; Soyer, C.; Paquet, J. B.; Grondel, S.; Cattan, E.

    2014-03-01

    In the last decade, many researchers pursued the development of tiny flying robots inspired by natural flyers destined for the exploration of confined spaces, for example. Within this context, our main objective is to devise a flying robot bioinspired from insect in terms of size and wing kinematics using MEMS technologies. For this purpose, an original design has been developed around resonant thorax and wings by the way of an indirect actuation and a concise transmission whereas the all-polymer prototypes are obtained using a micromachining SU-8 photoresist process. This paper reports our recent progress on the design of a flapping-wing robotic insect as well as on the characterization of its performance. Prototypes with a wingspan of 3 cm and a mass of 22 mg are achieved. Due to the introduction of an innovative compliant link, large and symmetrical bending angles of 70° are obtained at a flapping frequency of 30 Hz along with passive wing torsion while minimizing its energy expenditure. Furthermore, it leads to a mean lift force representing up to 75 % of the prototype weight as measured by an in-house force sensor. Different improvements are currently underway to increase the power-to-weight ratio of the prototype and to obtain an airborne prototype.

  6. Experimental investigation of a graphite-composite wing-box section for a reusable launch vehicle

    SciTech Connect

    Sawyer, J.W.; Bush, H.; Sutter, T.

    1997-01-01

    The use of graphite-composites as primary structure is essential for the development of a cost effective single-stage-to-orbit reusable launch vehicle (RLV) to replace the Space Shuttle. A full-scale segment of a graphite-composite wing was designed and fabricated by an industry team and tested at NASA Langley Research Center as a part of the RLV technology development program. The wing-box test component was 1.5 m wide by 3.0 m long and 1.1 m deep. It was construction from honeycomb sandwich panels with graphite-bisaleimide composite skins. The test component was loaded to design limit load in reverse bending followed by a test to design ultimate load, also in reverse bending. It was then loaded to failure. Resistance and fiber optic gages were used to measure strains in the wing box section during the test. A comprehensive finite element analysis of the specimen was performed. The test results verified the structural integrity of the wing-box component for RLV design loads, and good correlation between test and analysis was obtained. Both the failure location and the failure load were accurately predicted by the analysis. {copyright} {ital 1997 American Institute of Physics.}

  7. Experimental investigation of a graphite-composite wing-box section for a reusable launch vehicle

    NASA Astrophysics Data System (ADS)

    Sawyer, James Wayne; Bush, Harold; Sutter, Tom

    1997-01-01

    The use of graphite-composites as primary structure is essential for the development of a cost effective single-stage-to-orbit reusable launch vehicle (RLV) to replace the Space Shuttle. A full-scale segment of a graphite-composite wing was designed and fabricated by an industry team and tested at NASA Langley Research Center as a part of the RLV technology development program. The wing-box test component was 1.5 m wide by 3.0 m long and 1.1 m deep. It was construction from honeycomb sandwich panels with graphite-bisaleimide composite skins. The test component was loaded to design limit load in reverse bending followed by a test to design ultimate load, also in reverse bending. It was then loaded to failure. Resistance and fiber optic gages were used to measure strains in the wing box section during the test. A comprehensive finite element analysis of the specimen was performed. The test results verified the structural integrity of the wing-box component for RLV design loads, and good correlation between test and analysis was obtained. Both the failure location and the failure load were accurately predicted by the analysis.

  8. Volumetric visualization of the near and far field wake in flapping wings

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Cheng, Bo; Deng, Xinyan; Bio-Robotics Lab Team

    2013-11-01

    The flapping wings of flying animals create complex vortex wake structure, understanding its spatial and temporal distribution is fundamental to animal flight theory. In this study, we applied the volumetric 3-component velocimetry to capture both the near- and far-field flow generated by a pair of mechanical flapping wings. For the first time, the complete three-dimensional wake structure and its evolution throughout a wing stroke were quantified and presented. The general vortex wake structure maintains a quite consistent form: vortex rings in the near-field and two shear layers in the far-field. In specific, vortex rings shed periodically from the wings and are linked to each other in successive strokes. In the far-field, the shed vortex rings evolve into two parallel shear layers with dominant vorticity convected from tip and root vortices. The shear layers are nearly stationary in space compared to the periodic vortex rings shed in the near field. In addition, downwash passes through the centers of the vortex rings and extends downward between the two shear layers. This work is supported by AFOSR.

  9. Fracture Mechanics Analyses of the Slip-Side Joggle Regions of Wing-Leading Edge Panels

    NASA Technical Reports Server (NTRS)

    Raju, Ivatury S.; Knight, Norman F., Jr.; Song, Kyongchan; Phillips, Dawn R.

    2010-01-01

    The Space Shuttle Orbiter wing comprises of 22 leading edge panels on each side of the wing. These panels are part of the thermal protection system that protects the Orbiter wings from extreme heating that take place on the reentry in to the earth atmosphere. On some panels that experience extreme heating, liberation of silicon carbon (SiC) coating was observed on the slip side regions of the panels. Global structural and local fracture mechanics analyses were performed on these panels as a part of the root cause investigation of this coating liberation anomaly. The wing-leading-edge reinforced carbon-carbon (RCC) panels, Panel 9, T-seal 10, and Panel 10, are shown in Figure 1 and the progression of the stress analysis models is presented in Figure 2. The global structural analyses showed minimal interaction between adjacent panels and the T-seal that bridges the gap between the panels. A bounding uniform temperature is applied to a representative panel and the resulting stress distribution is examined. For this loading condition, the interlaminar normal stresses showed negligible variation in the chord direction and increased values in the vicinity of the slip-side joggle shoulder. As such, a representative span wise slice on the panel can be taken and the cross section can be analyzed using plane strain analysis.

  10. 3-D flow and scour near a submerged wing dike: ADCP measurements on the Missouri River

    USGS Publications Warehouse

    Jamieson, E.C.; Rennie, C.D.; Jacobson, R.B.; Townsend, R.D.

    2011-01-01

    Detailed mapping of bathymetry and three-dimensional water velocities using a boat-mounted single-beam sonar and acoustic Doppler current profiler (ADCP) was carried out in the vicinity of two submerged wing dikes located in the Lower Missouri River near Columbia, Missouri. During high spring flows the wing dikes become submerged, creating a unique combination of vertical flow separation and overtopping (plunging) flow conditions, causing large-scale three-dimensional turbulent flow structures to form. On three different days and for a range of discharges, sampling transects at 5 and 20 m spacing were completed, covering the area adjacent to and upstream and downstream from two different wing dikes. The objectives of this research are to evaluate whether an ADCP can identify and measure large-scale flow features such as recirculating flow and vortex shedding that develop in the vicinity of a submerged wing dike; and whether or not moving-boat (single-transect) data are sufficient for resolving complex three-dimensional flow fields. Results indicate that spatial averaging from multiple nearby single transects may be more representative of an inherently complex (temporally and spatially variable) three-dimensional flow field than repeated single transects. Results also indicate a correspondence between the location of calculated vortex cores (resolved from the interpolated three-dimensional flow field) and the nearby scour holes, providing new insight into the connections between vertically oriented coherent structures and local scour, with the unique perspective of flow and morphology in a large river.

  11. Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings VI : Wings and Nacelles with Pusher Propeller

    NASA Technical Reports Server (NTRS)

    Wood, Donald H; Bioletti, Carlton

    1935-01-01

    This report is the sixth of a series giving wind tunnel tests results on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. The present report gives the results of tests of a radial-engine nacelle with pusher propeller in 17 positions with reference to a Clark Y wing; tests of the same nacelle and propeller in three positions with reference to a thick wing; and tests of a body and pusher propeller with the thick wing, simulating the case of a propeller driven by an extension shaft from an engine within the wing. Some preliminary tests were made on pusher nacelles alone.

  12. Wing Download Results from a Test of a 0.658-Scale V-22 Rotor and Wing

    NASA Technical Reports Server (NTRS)

    Felker, Fort F.

    1992-01-01

    A test of a 0.658-scale V-22 rotor and wing was conducted in the 40 x 80 Foot Wind Tunnel at Ames Research Center. One of the principal objectives of the test was to measure the wing download in hover for a variety of test configurations. The wing download and surface pressures were measured for a wide range of thrust coefficients, with five different flap angles, two nacelle angles, and both directions or rotor rotation. This paper presents these results, and describes a new method for interpreting wing surface pressure data in hover. This method shows that the wing flap can produce substantial lift loads in hover.

  13. 7. Interior view of open secretarial space looking toward offices ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Interior view of open secretarial space looking toward offices and exterior door; showing opened doorway to office; northwest corner of west wing; view to west. - Ellsworth Air Force Base, Administration Office, 2704 George Drive, Blackhawk, Meade County, SD

  14. Interior view of first floor office space located in southeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of first floor office space located in southeast corner of east wing; camera facing southeast. - Mare Island Naval Shipyard, Marine Prison, Suisun Avenue, west side between Mesa Road & San Pablo, Vallejo, Solano County, CA

  15. Biomechanical basis of wing and haltere coordination in flies.

    PubMed

    Deora, Tanvi; Singh, Amit Kumar; Sane, Sanjay P

    2015-02-01

    The spectacular success and diversification of insects rests critically on two major evolutionary adaptations. First, the evolution of flight, which enhanced the ability of insects to colonize novel ecological habitats, evade predators, or hunt prey; and second, the miniaturization of their body size, which profoundly influenced all aspects of their biology from development to behavior. However, miniaturization imposes steep demands on the flight system because smaller insects must flap their wings at higher frequencies to generate sufficient aerodynamic forces to stay aloft; it also poses challenges to the sensorimotor system because precise control of wing kinematics and body trajectories requires fast sensory feedback. These tradeoffs are best studied in Dipteran flies in which rapid mechanosensory feedback to wing motor system is provided by halteres, reduced hind wings that evolved into gyroscopic sensors. Halteres oscillate at the same frequency as and precisely antiphase to the wings; they detect body rotations during flight, thus providing feedback that is essential for controlling wing motion during aerial maneuvers. Although tight phase synchrony between halteres and wings is essential for providing proper timing cues, the mechanisms underlying this coordination are not well understood. Here, we identify specific mechanical linkages within the thorax that passively mediate both wing-wing and wing-haltere phase synchronization. We demonstrate that the wing hinge must possess a clutch system that enables flies to independently engage or disengage each wing from the mechanically linked thorax. In concert with a previously described gearbox located within the wing hinge, the clutch system enables independent control of each wing. These biomechanical features are essential for flight control in flies. PMID:25605915

  16. Fractal dimension in butterflies' wings: a novel approach to understanding wing patterns?

    PubMed

    Castrejón-Pita, A A; Sarmiento-Galán, A; Castrejón-Pita, J R; Castrejón-García, R

    2005-05-01

    The geometrical complexity in the wings of several, taxonomically different butterflies, is analyzed in terms of their fractal dimension. Preliminary results provide some evidence on important questions about the (dis)similarity of the wing patterns in terms of their fractal dimension. The analysis is restricted to two groups which are widely used in the literature as typical examples of mimicry, and a small number of unrelated species, thus implying the consideration of only a fraction of the wing pattern diversity. The members of the first mimicry ring, composed by the species Danaus plexippus (better known as the monarch butterfly), and the two subspecies Basilarchia archippus obsoleta (or northern viceroy) and Basilarchia archippus hoffmanni (or tropical viceroy), are found to have a very similar value for the fractal dimension of their wing patterns, even though they do not look very similar at first sight. It is also found that the female of another species (Neophasia terlootii), which looks similar to the members of the previous group, does not share the same feature, while the Lycorea ilione albescens does share it. For the members of the second group of mimicry related butterflies, the Greta nero nero and the Hypoleria cassotis, it is shown that they also have very close values for the fractal dimension of their wing patterns. Finally, it is shown that other species, which apparently have very similar wing patterns, do not have the same fractal dimension. A possible, not completely tested hypothesis is then conjectured: the formation of groups by individuals whose wing patterns have an almost equal fractal dimension may be due to the fact that they do share the same developmental raw material, and that this common feature is posteriorly modified by natural selection, possibly through predation. PMID:15614549

  17. WINGDES2 - WING DESIGN AND ANALYSIS CODE

    NASA Technical Reports Server (NTRS)

    Carlson, H. W.

    1994-01-01

    This program provides a wing design algorithm based on modified linear theory which takes into account the effects of attainable leading-edge thrust. A primary objective of the WINGDES2 approach is the generation of a camber surface as mild as possible to produce drag levels comparable to those attainable with full theoretical leading-edge thrust. WINGDES2 provides both an analysis and a design capability and is applicable to both subsonic and supersonic flow. The optimization can be carried out for designated wing portions such as leading and trailing edge areas for the design of mission-adaptive surfaces, or for an entire planform such as a supersonic transport wing. This program replaces an earlier wing design code, LAR-13315, designated WINGDES. WINGDES2 incorporates modifications to improve numerical accuracy and provides additional capabilities. A means of accounting for the presence of interference pressure fields from airplane components other than the wing and a direct process for selection of flap surfaces to approach the performance levels of the optimized wing surfaces are included. An increased storage capacity allows better numerical representation of those configurations that have small chord leading-edge or trailing-edge design areas. WINGDES2 determines an optimum combination of a series of candidate surfaces rather than the more commonly used candidate loadings. The objective of the design is the recovery of unrealized theoretical leading-edge thrust of the input flat surface by shaping of the design surface to create a distributed thrust and thus minimize drag. The input consists of airfoil section thickness data, leading and trailing edge planform geometry, and operational parameters such as Mach number, Reynolds number, and design lift coefficient. Output includes optimized camber surface ordinates, pressure coefficient distributions, and theoretical aerodynamic characteristics. WINGDES2 is written in FORTRAN V for batch execution and has been

  18. Cassini's Flyby Through Rhea's Distant Alfven Wing

    NASA Astrophysics Data System (ADS)

    Khurana, K. K.; Krupp, N.; Kivelson, M. G.; Roussos, E.; Russell, C. T.; Dougherty, M. K.

    2012-09-01

    During its 132nd orbit around Saturn, Cassini flew downstream of Rhea at the closest approach (CA) distance of 102 RH (June 3, 2010). The electron channels of the MIMI-LEMMS instruments showed sharp depletions in particle counts over the energy range of 18-183 keV near the CA (see Figure 1). In addition the magnetometer onboard Cassini measured a sharp rotation of the magnetic field suggesting that the field perturbation is Alfvénic in nature (Figure 1). A detailed analysis of the signature shows that the observed signatures were produced by the passage of the Cassini spacecraft through the northern Alfvén wing of Rhea. The formation of Alfvénic wings by Rhea is a major surprise because the moon is known to act mainly as an inert plasma absorber (Khurana et al. 2007). The discovery of Alfvén wings suggests that Rhea is able to slow the upstream plasma either through plasma pick-up or through an enhanced ionospheric conductivity. The implied Alfvénic Mach number of unity is understandable if the plasma density was a factor of 2 higher during this flyby than during the first flyby. The Alfvén wing is displaced inward from Rhea because the wave propagates towards Saturn at large distances from Rhea. A second downstream passage of Cassini at a large distance (54 RH) from Rhea occurred on October 17, 2010 during orbit 139. The data from the MIMILEMMS instrument again show sharp depletions in most of the electron channels. The magnetic data on the other hand do not show a related magnetic field rotation. The observed signature can be understood if the spacecraft was downstream of the Alfvén wing where the electrons are still depleted but no passage through the current carrying region occurs. If average Alfvén Mach number = 1 as in previous case, the Alfvén wing would be located at X = 22 RH whereas the spacecraft flew by X = 48 RH (way downstream). The absorption region is again shifted inward towards Saturn from Rhea's location because the nearly dipolar flux

  19. Flapping wing PIV and force measurements

    NASA Astrophysics Data System (ADS)

    Cameron, Benjamin H.

    Flapping wing aerodynamics has been of interest to engineers recently due in part to the DARPA (Defense Advanced Research Projects Agency) MAV (Micro-Aerial Vehicle) initiative. MAVs are small unmanned aerial vehicles with length scales similar to birds and insects. Flapping wing MAVs would serve as mobile and stealthy sensing platforms capable of gathering intelligence in hazardous and physically inaccessible locations. Traditional means of lift and thrust generation become inefficient when scaled to these sizes, therefore a flapping wing propulsion system will be necessary. The design of a flapping wing MAV requires the ability to measure forces and velocities around the wing. Three components of velocity were measured in the wake of a two dimensional (2D) flapping airfoil model using a novel application of stereoscopic DPIV (Digital Particle Image Velocimetry). One component of force was measured using a newly proposed method outlined in the dissertation. The force measurement technique relies on a specific sequence of data acquisition, which has the benefit of reducing measurement uncertainty and noise. No experiments of this type have been conducted, and no direct aerodynamic force data exists for the low Reynolds numbers applicable to flapping wing MAVs. The well-established stereoscopic DPIV technique produces relatively low uncertainties while the new force measurement technique has not been previously tested. Theoretical analysis and experimental results show that aerodynamic forces are attainable for chord Reynolds numbers as low as 1,000, which is significantly lower than previous studies. PIV measurements reveal symmetric and asymmetric wake topologies for a NACA 0012 and flat plate airfoil. A sinusoidally heaving flat plate airfoil produces highly deflected wakes for a wider range of flapping conditions than a NACA 0012 airfoil. Deflected wakes are of potentially interest since both lift and thrust components of force are developed. The flat plate also

  20. Aerodynamic role of dynamic wing morphing in hummingbird maneuvering flight

    NASA Astrophysics Data System (ADS)

    Ren, Yan; Shallcross, Gregory; Dong, Haibo; Deng, Xinyan; Tobalske, Bret; Flow Simulation Research Group Team; Bio-robotics lab Collaboration; University of Montana Flight Laboratory Collaboration

    2014-11-01

    The flexibility and deformation of hummingbird wing gives hummingbird a great degree of control over fluid forces in flapping flight. Unlike insect wing's passive deformation, hummingbird wing employs a more complicated wing morphing mechanism through both active muscle control and passive feather-air interaction, which results in highly complex 3D wing topology variations during the unsteady flight. Three camera high speed (1000 fps) high resolution digital video was taken and digitized to measure 3D wing conformation in all its complexity during steady flying and maneuvering. Results have shown that the dynamic wing morphing is more prominent in maneuvering flight. Complicated cambering and twisting patterns are observed along the wing pitching axis. A newly developed immersed boundary method which realistically models wing-joint-body of the hummingbird is then employed to simulate the flow associated with dynamic morphing. The simulations provide a first of its kind glimpse of the fluid and vortex dynamics associated with dynamic wing morphing and aerodynamic force computations allow us to gain a better understanding of force producing mechanisms in hummingbird maneuvering flight. This work is supported by AFOSR FA9550-12-1-007 and NSF CEBT-1313217.

  1. Upstroke wing flexion and the inertial cost of bat flight

    PubMed Central

    Riskin, Daniel K.; Bergou, Attila; Breuer, Kenneth S.; Swartz, Sharon M.

    2012-01-01

    Flying vertebrates change the shapes of their wings during the upstroke, thereby decreasing wing surface area and bringing the wings closer to the body than during downstroke. These, and other wing deformations, might reduce the inertial cost of the upstroke compared with what it would be if the wings remained fully extended. However, wing deformations themselves entail energetic costs that could exceed any inertial energy savings. Using a model that incorporates detailed three-dimensional wing kinematics, we estimated the inertial cost of flapping flight for six bat species spanning a 40-fold range of body masses. We estimate that folding and unfolding comprises roughly 44 per cent of the inertial cost, but that the total inertial cost is only approximately 65 per cent of what it would be if the wing remained extended and rigid throughout the wingbeat cycle. Folding and unfolding occurred mostly during the upstroke; hence, our model suggests inertial cost of the upstroke is not less than that of downstroke. The cost of accelerating the metacarpals and phalanges accounted for around 44 per cent of inertial costs, although those elements constitute only 12 per cent of wing weight. This highlights the energetic benefit afforded to bats by the decreased mineralization of the distal wing bones. PMID:22496186

  2. An aerodynamic tradeoff study of the scissor wing configuration

    NASA Technical Reports Server (NTRS)

    Selberg, Bruce P.; Rokhsaz, Kamran; Housh, Clinton S.

    1990-01-01

    A scissor wing configuration, consisting of two independently sweeping wings was numerically studied. This configuration was also compared with an equivalent fixed wing baseline. Aerodynamic and stability and control characteristics of these geometries were investigated over a wide range of flight Mach numbers. It is demonstrated that in the purely subsonic flight regime, the scissor wing can achieve higher aerodynamic efficiency as the result of slightly higher aspect ratio. In the transonic regime, the lift to drag ratio of the scissor wing is shown to be higher than that of the baseline, for higer values of the lift coefficient. This tends to make the scissor wing more efficient during transonic cruise at high altitudes as well as during air combat at all altitudes. In supersonic flight, where the wings are maintained at maximum sweep angle, the scissor wing is shown to have a decided advantage in terms of reduced wave drag. From the view point of stability and control, the scissor wing is shown to have distinct advantages. It is shown that this geometry can maintain a constant static margin in supersonic as well as subsonic flight, by proper sweep scheduling. Furthermore, it is demonstrated that addition of wing mounted elevons can greatly enhance control authority in pitch and roll.

  3. Advanced composites wing study program, volume 2

    NASA Technical Reports Server (NTRS)

    Harvey, S. T.; Michaelson, G. L.

    1978-01-01

    The study on utilization of advanced composites in commercial aircraft wing structures was conducted as a part of the NASA Aircraft Energy Efficiency Program to establish, by the mid-1980s, the technology for the design of a subsonic commercial transport aircraft leading to a 40% fuel savings. The study objective was to develop a plan to define the effort needed to support a production commitment for the extensive use of composite materials in wings of new generation aircraft that will enter service in the 1985-1990 time period. Identification and analysis of what was needed to meet the above plan requirements resulted in a program plan consisting of three key development areas: (1) technology development; (2) production capability development; and (3) integration and validation by designing, building, and testing major development hardware.

  4. Charge Capacity of Piezoelectric Membrane Wings

    NASA Astrophysics Data System (ADS)

    Grybas, Matthew; Hubner, J. Paul

    2015-11-01

    Micro air vehicles (MAVs) have small wings often fabricated with flexible frames and membranes. These membranes flex and vibrate. Piezoelectric films have the ability to convert induced stress or strain into electrical energy. Thus, it is of interest to investigate if piezoelectric films can be used as a structural member of an MAV wing and generate both lift and energy through passive vibrations. Both a shaker test and a wind tunnel test have been conducted to characterize and assess energy production and aerodynamic characteristics including lift, drag and efficiency. The piezoelectric film has been successful as a lifting surface and produces a measurable charge. This work was supported by NSF REU Site Award 1358991.

  5. Wing Shape Sensing from Measured Strain

    NASA Technical Reports Server (NTRS)

    Pak, Chan-Gi

    2015-01-01

    A new two step theory is investigated for predicting the deflection and slope of an entire structure using strain measurements at discrete locations. In the first step, a measured strain is fitted using a piecewise least squares curve fitting method together with the cubic spline technique. These fitted strains are integrated twice to obtain deflection data along the fibers. In the second step, computed deflection along the fibers are combined with a finite element model of the structure in order to extrapolate the deflection and slope of the entire structure through the use of System Equivalent Reduction and Expansion Process. The theory is first validated on a computational model, a cantilevered rectangular wing. It is then applied to test data from a cantilevered swept wing model.

  6. Wing Leading Edge Joint Laminar Flow Tests

    NASA Technical Reports Server (NTRS)

    Drake, Aaron; Westphal, Russell V.; Zuniga, Fanny A.; Kennelly, Robert A., Jr.; Koga, Dennis J.

    1996-01-01

    An F-104G aircraft at NASA's Dryden Flight Research Center has been equipped with a specially designed and instrumented test fixture to simulate surface imperfections of the type likely to be present near the leading edge on the wings of some laminar flow aircraft. The simulated imperfections consisted of five combinations of spanwise steps and gaps of various sizes. The unswept fixture yielded a pressure distribution similar to that of some laminar flow airfoils. The experiment was conducted at cruise conditions typical for business-jets and light transports: Mach numbers were in the range 0.5-0.8, and unit Reynolds numbers were 1.5-2.5 million per foot. Skin friction measurements indicated that laminar flow was often maintained for some distance downstream of the surface imperfections. Further work is needed to more precisely define transition location and to extend the experiments to swept-wing conditions and a broader range of imperfection geometries.

  7. Performance of rotating-wing aircraft

    NASA Technical Reports Server (NTRS)

    Hohenemser, K

    1938-01-01

    Up to the present there has been no coordinated presentation from which the influence of the constants essential for the performance of rotating-wing aircraft could be obtained in a systematic manner. The attempt at such a survey is made in the following, whereby nonessential factors, such as effect of blade form, blade profile, blade number, and blade twist on the performances are disregarded. Even the torsional flexibility of the blades is overlooked.

  8. Maintenance cost study of rotary wing aircraft

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The feasibility was studied of predicting rotary wing operation maintenance costs by using several aircraft design factors for the aircraft dynamic systems. The dynamic systems considered were engines, drives and transmissions, rotors, and flight controls. Multiple regression analysis was used to correlate aircraft design and operational factors with manhours per flight hour, and equations for each dynamic system were developed. Results of labor predictions using the equations compare favorably with actual values.

  9. Integrated aerodynamic-structural-control wing design

    NASA Technical Reports Server (NTRS)

    Rais-Rohani, M.; Haftka, R. T.; Grossman, B.; Unger, E. R.

    1992-01-01

    The aerodynamic-structural-control design of a forward-swept composite wing for a high subsonic transport aircraft is considered. The structural analysis is based on a finite-element method. The aerodynamic calculations are based on a vortex-lattice method, and the control calculations are based on an output feedback control. The wing is designed for minimum weight subject to structural, performance/aerodynamic and control constraints. Efficient methods are used to calculate the control-deflection and control-effectiveness sensitivities which appear as second-order derivatives in the control constraint equations. To suppress the aeroelastic divergence of the forward-swept wing, and to reduce the gross weight of the design aircraft, two separate cases are studied: (1) combined application of aeroelastic tailoring and active controls; and (2) aeroelastic tailoring alone. The results of this study indicated that, for this particular example, aeroelastic tailoring is sufficient for suppressing the aeroelastic divergence, and the use of active controls was not necessary.

  10. Continuous measurement of aircraft wing icing

    NASA Technical Reports Server (NTRS)

    Yao, Stephen S. C.

    1994-01-01

    Ice formation on the wings of aircraft is a problem that has plagued air travel since its inception. Several recent incidents have been attributed to ice formation on the lifting surfaces of wings. This paper describes a SBIR Phase 1 research effort on the use of small flat dielectric sensors in detecting a layer of ice above the sensor. The sensors are very small, lightweight, and inexpensive. The electronics package that controls the sensor is also small, and could be even smaller using commonly available miniaturization technologies. Thus, several sensors could be placed on a surface such that a representative ice thickness profile could be measured. The benefits offered by developing this technology go beyond the safety improvements realized by monitoring ice formation on the wings of an aircraft. Continuous monitoring of anti-icing fluid concentrations on the ground would warn the pilot of impending fluid failure as well as allowing the stations to use less de-icing solution per aircraft. This in turn would increase the safety of takeoffs and reduce the overall discharge of de-icing solution into the environment, thus reducing the biohazard of the de-icing procedure.

  11. Smart wing wind tunnel test results

    NASA Astrophysics Data System (ADS)

    Scherer, Lewis B.; Martin, Christopher A.; Appa, Kari; Kudva, Jayanth N.; West, Mark N.

    1997-05-01

    The use of smart materials technologies can provide unique capabilities in improving aircraft aerodynamic performance. Northrop Grumman built and tested a 16% scale semi-span wind tunnel model of the F/A-18 E/F for the on-going DARPA/WL Smart Materials and Structures-Smart Wing Program. Aerodynamic performance gains to be validated included increase in the lift to drag ratio, increased pitching moment (Cm), increased rolling moment (Cl) and improved pressure distribution. These performance gains were obtained using hingeless, contoured trailing edge control surfaces with embedded shape memory alloy (SMA) wires and spanwise wing twist via a SMA torque tube and are compared to a conventional wind tunnel model with hinged control surfaces. This paper presents an overview of the results from the first wind tunnel test performed at the NASA Langley's 16 ft Transonic Dynamic Tunnel. Among the benefits demonstrated are 8 - 12% increase in rolling moment due to wing twist, a 10 - 15% increase in rolling moment due to contoured aileron, and approximately 8% increase in lift due to contoured flap, and improved pressure distribution due to trailing edge control surface contouring.

  12. Study of cross-correlation signals in a data-driven approach for damage classification in aircraft wings

    NASA Astrophysics Data System (ADS)

    Camacho-Navarro, Jhonatan; Ruiz, Magda; Villamizar, Rodolfo; Mujica, Luis; Güemes, Alfredo; González-Requema, Ignacio

    2015-07-01

    This paper discusses, experimental results of classifying several mass adding in a wing aircraft structure, using cross-correlated piezoelectric signals, represented by principal components. Piezoelectric signals are applied and recorded at specific points of the structure under analysis. Then, statistical features are obtained by means of principal component analysis to the correlation between excitation and response signals. Unsupervised learning is implemented to the reduced feature space, in order to identify clusters of damaged cases. The main result of this paper is the advantage resulting from using cross-correlated signals, evaluated through the performance of clustering indexes. Experimental data are collected from two test structures: i.) A turbine blade of a commercial aircraft and ii.) The skin panel of the torsion box of a wing. Damages are induced adding masses at different locations of the wing section surface. The results obtained show the effectiveness of the methodology to distinguish between different damage cases.

  13. Pressure distributions induced by elevon deflections on swept wings and adjacent end-plate surfaces at Mach 6

    NASA Technical Reports Server (NTRS)

    Kaufman, L. G., II; Johnson, C. B.

    1977-01-01

    Surface pressure distributions are presented for regions where three-dimensional separated flow effects are prominent on swept-wing-elevon-end-plate models of 0 degree, 50 degree, and 70 degree sweepback, and with 0 degree, 10 degree, 20 degree, and 30 degree elevon deflections. Surface-oil-flow photographs and pressure distributions on the flat-plate wing, elevon, and end-plate surfaces are presented for numerous geometric variations, including various spacings between the elevon and the end plate, with and without a tip fin. The data, for a free-stream Mach number of 6 and a wing-root-chord Reynolds number of 20 x 10 to the sixth power, reveal considerably larger regions of elevon induced loads on the adjacent end-plate surface than would be anticipated by using inviscid flow analyses.

  14. Supersonic wing and wing-body shape optimization using an adjoint formulation

    NASA Technical Reports Server (NTRS)

    Reuther, James; Jameson, Antony

    1995-01-01

    This paper describes the implementation of optimization techniques based on control theory for wing and wing-body design of supersonic configurations. The work represents an extension of our earlier research in which control theory is used to devise a design procedure that significantly reduces the computational cost by employing an adjoint equation. In previous studies it was shown that control theory could be used toeviseransonic design methods for airfoils and wings in which the shape and the surrounding body-fitted mesh are both generated analytically, and the control is the mapping function. The method has also been implemented for both transonic potential flows and transonic flows governed by the Euler equations using an alternative formulation which employs numerically generated grids, so that it can treat more general configurations. Here results are presented for three-dimensional design cases subject to supersonic flows governed by the Euler equation.

  15. All-theoretical prediction of cabin noise due to impingement of propeller vortices on a wing structure

    NASA Technical Reports Server (NTRS)

    Martinez, R.; Cole, J. E., III; Martini, K.; Westagard, A.

    1987-01-01

    Reported calculations of structure-borne cabin noise for a small twin engine aircraft powered by tractor propellers rely on the following three-stage methodological breakup of the problem: (1) the unsteady-aerodynamic prediction of wing lift harmonics caused by the whipping action of the vortex system trailed from each propeller; (2) the associated wing/fuselage structural response; (3) the cabin noise field for the computed wall vibration. The first part--the estimate of airloads--skirts a full-fledged aeroelastic situation by assuming the wing to be fixed in space while cancelling the downwash field of the cutting vortices. The model is based on an approximate high-frequency lifting-surface theory justified by the blade rate and flight Mach number of application. Its results drive a finite-element representation of the wing accounting for upper and lower skin surfaces, spars, ribs, and the presence of fuel. The fuselage, modeled as a frame-stiffened cylindrical shell, is bolted to the wing.

  16. Simulations of dynamics of plunge and pitch of a three-dimensional flexible wing in a low Reynolds number flow

    NASA Astrophysics Data System (ADS)

    Qi, Dewei; Liu, Yingming; Shyy, Wei; Aono, Hikaru

    2010-09-01

    The lattice Boltzmann flexible particle method (LBFPM) is used to simulate fluid-structure interaction and motion of a flexible wing in a three-dimensional space. In the method, a beam with rectangular cross section has been discretized into a chain of rigid segments. The segments are connected through ball and socket joints at their ends and may be bent and twisted. Deformation of flexible structure is treated with a linear elasticity model through bending and twisting. It is demonstrated that the flexible particle method (FPM) can approximate the nonlinear Euler-Bernoulli beam equation without resorting to a nonlinear elasticity model. Simulations of plunge and pitch of flexible wing at Reynolds number Re=136 are conducted in hovering condition by using the LBFPM. It is found that both lift and drag forces increase first, then decrease dramatically as the bending rigidity in spanwise direction decreases and that the lift and drag forces are sensitive to rigidity in a certain range. It is shown that the downwash flows induced by wing tip and trailing vortices in wake area are larger for a flexible wing than for a rigid wing, lead to a smaller effective angle of attack, and result in a larger lift force.

  17. Applications of Ko Displacement Theory to the Deformed Shape Predictions of the Doubly-Tapered Ikhana Wing

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Richards, W. Lance; Fleischer, Van Tran

    2009-01-01

    The Ko displacement theory, formulated for weak nonuniform (slowly changing cross sections) cantilever beams, was applied to the deformed shape analysis of the doubly-tapered wings of the Ikhana unmanned aircraft. The two-line strain-sensing system (along the wingspan) was used for sensing the bending strains needed for the wing-deformed shapes (deflections and cross-sectional twist) analysis. The deflection equation for each strain-sensing line was expressed in terms of the bending strains evaluated at multiple numbers of strain-sensing stations equally spaced along the strain-sensing line. For the preflight shape analysis of the Ikhana wing, the strain data needed for input to the displacement equations for the shape analysis were obtained from the nodal-stress output of the finite-element analysis. The wing deflections and cross-sectional twist angles calculated from the displacement equations were then compared with those computed from the finite-element computer program. The Ko displacement theory formulated for weak nonlinear cantilever beams was found to be highly accurate in the deformed shape predictions of the doubly-tapered Ikhana wing.

  18. Tables for the Rapid Estimation of Downwash and Sidewash Behind Wings Performing Various Motions at Supersonic Speeds

    NASA Technical Reports Server (NTRS)

    Bobbitt, Percy J.

    1959-01-01

    Equations for the downwash and sidewash due to supersonic yawed and unswept horseshoe vortices have been utilized in formulating tables and charts to permit a rapid estimation of the flow velocities behind wings performing various steady motions. Tabulations are presented of the downwash and sidewash in the wing vertical plane of symmetry due to a unit-strength yawed horseshoe vortex located at 20 equally spaced spanwise positions along lifting lines of various sweeps. (The bound portion of the yawed vortex is coincident with the lifting line.) Charts are presented for the purpose of estimating the spanwise variations of the flow-field velocities and give longitudinal variations of the downwash and sidewash at a nuMber of vertical and spanwise locations due to a unit-strength unswept horseshoe vortex. Use of the tables and charts to calculate wing downwash or sidewash requires a knowledge of the wing spanwise distribution of circulation. Sample computations for the rolling sidewash and angle-of-attack downwash behind a typical swept wing are presented to demonstrate the use of the tables and charts.

  19. Steady pressure measurements on an Aeroelastic Research Wing (ARW-2)

    NASA Technical Reports Server (NTRS)

    Sandford, Maynard C.; Seidel, David A.; Eckstrom, Clinton V.

    1994-01-01

    Transonic steady and unsteady pressure tests have been conducted in the Langley transonic dynamics tunnel on a large elastic wing known as the DAST ARW-2. The wing has a supercritical airfoil, an aspect ratio of 10.3, a leading-edge sweep back angle of 28.8 degrees, and two inboard and one outboard trailing-edge control surfaces. Only the outboard control surface was deflected to generate steady and unsteady flow over the wing during this study. Only the steady surface pressure, control-surface hinge moment, wing-tip deflection, and wing-root bending moment measurements are presented. The results from this elastic wing test are in tabulated form to assist in calibrating advanced computational fluid dynamics (CFD) algorithms.

  20. Modeling and Optimization for Morphing Wing Concept Generation

    NASA Technical Reports Server (NTRS)

    Skillen, Michael D.; Crossley, William A.

    2007-01-01

    This report consists of two major parts: 1) the approach to develop morphing wing weight equations, and 2) the approach to size morphing aircraft. Combined, these techniques allow the morphing aircraft to be sized with estimates of the morphing wing weight that are more credible than estimates currently available; aircraft sizing results prior to this study incorporated morphing wing weight estimates based on general heuristics for fixed-wing flaps (a comparable "morphing" component) but, in general, these results were unsubstantiated. This report will show that the method of morphing wing weight prediction does, in fact, drive the aircraft sizing code to different results and that accurate morphing wing weight estimates are essential to credible aircraft sizing results.

  1. Estimating the weight of generally configured dual wing systems

    NASA Technical Reports Server (NTRS)

    Cronin, D. L.; Somnay, R. J.

    1985-01-01

    Formulas available for the weight estimation of monoplane wings cannot be said to be appropriate for the estimation of generally configured dual wing systems. In the present paper a method is described which simultaneously generates a structural weight estimate and a fully stressed, quasi-optimal structure for a model of a dual wing system. The method is fast and inexpensive. It is ideally suited to preliminary design. To illustrate the method, a dual wing system and a conventional wing system are sized. Numerical computation is shown to be suitably fast for both cases and, for both cases, convergence to a final configuration is shown to be quite rapid. To illustrate the validity of the method, a conventional wing is sized and its weight obtained by the present method is compared to its weight determined by a reputable weight estimation formula. The results are shown to be very close.

  2. Vortex Interaction on Low Aspect Ratio Membrane Wings

    NASA Astrophysics Data System (ADS)

    Waldman, Rye M.; Breuer, Kenneth S.

    2013-11-01

    Inspired by the flight of bats and by recent interest in Micro Air Vehicles, we present measurements on the steady and unsteady behavior of low aspect ratio membrane wings. We conduct wind tunnel experiments with coupled force, kinematic, and flow field measurements, both on the wing and in the near wake. Membrane wings interact strongly with the vortices shed from the leading- and trailing-edges and the wing tips, and the details of the membrane support play an important role in the fluid-structure interaction. Membranes that are supported at the wing tip exhibit less membrane flutter, more coherent tip vortices, and enhanced lift. The interior wake can exhibit organized spanwise vortex shedding, and shows little influence from the tip vortex. In contrast, membranes with an unsupported wing tip show exaggerated static deformation, significant membrane fluttering and a diffuse, unsteady tip vortex. The unsteady tip vortex modifies the behavior of the interior wake, disrupting the wake coherence.

  3. Wing Weight Optimization Under Aeroelastic Loads Subject to Stress Constraints

    NASA Technical Reports Server (NTRS)

    Kapania, Rakesh K.; Issac, J.; Macmurdy, D.; Guruswamy, Guru P.

    1997-01-01

    A minimum weight optimization of the wing under aeroelastic loads subject to stress constraints is carried out. The loads for the optimization are based on aeroelastic trim. The design variables are the thickness of the wing skins and planform variables. The composite plate structural model incorporates first-order shear deformation theory, the wing deflections are expressed using Chebyshev polynomials and a Rayleigh-Ritz procedure is adopted for the structural formulation. The aerodynamic pressures provided by the aerodynamic code at a discrete number of grid points is represented as a bilinear distribution on the composite plate code to solve for the deflections and stresses in the wing. The lifting-surface aerodynamic code FAST is presently being used to generate the pressure distribution over the wing. The envisioned ENSAERO/Plate is an aeroelastic analysis code which combines ENSAERO version 3.0 (for analysis of wing-body configurations) with the composite plate code.

  4. Video measurements of instantaneous forces of flapping wing vehicles

    NASA Astrophysics Data System (ADS)

    Jennings, Alan; Mayhew, Michael; Black, Jonathan

    2015-12-01

    Flapping wings for small aerial vehicles have revolutionary potential for maneuverability and endurance. Ornithopters fail to achieve the performance of their biological equivalents, despite extensive research on how animals fly. Flapping wings produce peak forces due to the stroke reversal of the wing. This research demonstrates in-flight measurements of an ornithopter through the use of image processing, specifically measuring instantaneous forces. Results show that the oscillation about the flight path is significant, being about 20% of the mean velocity and up to 10 g's. Results match forces with deformations of the wing to contrast the timing and wing shape of the upstroke and the downstroke. Holding the vehicle fixed (e.g. wind tunnel testing or simulations) structural resonance is affected along with peak forces, also affecting lift. Non-contact, in-flight measurements are proposed as the best method for matching the flight conditions of flapping wing vehicles.

  5. Design synthesis and optimization of joined-wing transports

    NASA Technical Reports Server (NTRS)

    Gallman, John W.; Smith, Stephen C.; Kroo, Ilan M.

    1990-01-01

    A computer program for aircraft synthesis using a numerical optimizer was developed to study the application of the joined-wing configuration to transport aircraft. The structural design algorithm included the effects of secondary bending moments to investigate the possibility of tail buckling and to design joined wings resistant to buckling. The structural weight computed using this method was combined with a statistically-based method to obtain realistic estimates of total lifting surface weight and aircraft empty weight. A variety of 'optimum' joined-wing and conventional aircraft designs were compared on the basis of direct operating cost, gross weight, and cruise drag. The most promising joined-wing designs were found to have a joint location at about 70 percent of the wing semispan. The optimum joined-wing transport is shown to save 1.7 percent in direct operating cost and 11 percent in drag for a 2000 nautical mile transport mission.

  6. Fiber Optic Wing Shape Sensing on NASA's Ikhana UAV

    NASA Technical Reports Server (NTRS)

    Richards, Lance; Parker, Allen R.; Ko, William L.; Piazza, Anthony

    2008-01-01

    This document discusses the development of fiber optic wing shape sensing on NASA's Ikhana vehicle. The Dryden Flight Research Center's Aerostructures Branch initiated fiber-optic instrumentation development efforts in the mid-1990s. Motivated by a failure to control wing dihedral resulting in a mishap with the Helios aircraft, new wing displacement techniques were developed. Research objectives for Ikhana included validating fiber optic sensor measurements and real-time wing shape sensing predictions; the validation of fiber optic mathematical models and design tools; assessing technical viability and, if applicable, developing methodology and approaches to incorporate wing shape measurements within the vehicle flight control system; and, developing and flight validating approaches to perform active wing shape control using conventional control surfaces and active material concepts.

  7. Buffet characteristics of the F-8 supercritical wing airplane

    NASA Technical Reports Server (NTRS)

    Deangelis, V. M.; Monaghan, R. C.

    1977-01-01

    The buffet characteristics of the F-8 supercritical wing airplane were investigated. Wing structural response was used to determine the buffet characteristics of the wing and these characteristics are compared with wind tunnel model data and the wing flow characteristics at transonic speeds. The wingtip accelerometer was used to determine the buffet onset boundary and to measure the buffet intensity characteristics of the airplane. The effects of moderate trailing edge flap deflections on the buffet onset boundary are presented. The supercritical wing flow characteristics were determined from wind tunnel and flight static pressure measurements and from a dynamic pressure sensor mounted on the flight test airplane in the vicinity of the shock wave that formed on the upper surface of the wing at transonic speeds. The comparison of the airplane's structural response data to the supercritical flow characteristics includes the effects of a leading edge vortex generator.

  8. Simplifying a wing: diversity and functional consequences of digital joint reduction in bat wings.

    PubMed

    Bahlman, Joseph W; Price-Waldman, Rosalyn M; Lippe, Hannah W; Breuer, Kenneth S; Swartz, Sharon M

    2016-07-01

    Bat wings, like other mammalian forelimbs, contain many joints within the digits. These joints collectively affect dynamic three-dimensional (3D) wing shape, thereby affecting the amount of aerodynamic force a wing can generate. Bats are a speciose group, and show substantial variation in the number of wing joints. Additionally, some bat species have joints with extensor but no flexor muscles. While several studies have examined the diversity in number of joints and presence of muscles, musculoskeletal variation in the digits has not been interpreted in phylogenetic, functional or ecological contexts. To provide this context, the number of joints and the presence/absence of muscles are quantified for 44 bat species, and are mapped phylogenetically. It is shown that, relative to the ancestral state, joints and muscles were lost multiple times from different digits and in many lineages. It is also shown that joints lacking flexors undergo cyclical flexion and extension, in a manner similar to that observed in joints with both flexors and extensors. Comparison of species with contrasting feeding ecologies demonstrates that species that feed primarily on non-mobile food (e.g. fruit) have fewer fully active joints than species that catch mobile prey (e.g. insects). It is hypothesized that there is a functional trade-off between energetic savings and maneuverability. Having fewer joints and muscles reduces the mass of the wing, thereby reducing the energetic requirements of flapping flight, and having more joints increases the assortment of possible 3D wing shapes, thereby enhancing the range and fine control of aerodynamic force production and thus maneuverability. PMID:26969851

  9. Incompressible Turbulent Wing-Body Junction Flow

    NASA Technical Reports Server (NTRS)

    Krishnamurthy, R.; Cagle, Corey D.; Chandra, S.

    1998-01-01

    The overall objective of this study is to contribute to the optimized design of fan bypass systems in advanced turbofan engines. Increasing the engine bypass ratios have provided a major boost in engine performance improvement over the last fifty years. An engine with high bypass ratio (11-16:1) such as the Advanced Ducted Propulsion (ADP) is being developed and is expected to provide an additional 25% improvement in overall efficiency over the early turbofans. Such significant improvements in overall efficiency would reduce the cost per seat mile, which is a major government and Industry challenge for the 21th century. The research is part of the Advanced Subsonic Technology (AST) program that involves a NASA, U.S. Industry and FAA partnership with the goal of a safe and highly productive global air transportation system. The immediate objective of the study is to perform numerical simulation of duct-strut interactions to elucidate the loss mechanisms associated with this configuration that is typical of advanced turbofan engines such as ADP. However, at present experimental data for a duct-strut configuration are not available. Thus, as a first step a wing-body junction flow would be studied and is the specific objective of the present study. At the outset it is to be recognized that while duct-strut interaction flow is similar to that of wing-body junction flows, there are some differences owing to the presence of a wall at both ends of the strut. Likewise, some differences are due to the sheared inflow (as opposed to a uniform inflow) velocity profile. It is however expected that some features of a wing-body junction flow would persist. Next, some of the salient aspects of the complex flow near a wing-body junction, as revealed by various studies reported in the literature will be reviewed. One of the principle characteristics of the juncture flow, is the presence of the mean flow components in a plane perpendicular to the direction of the oncoming free

  10. Knowledge Discovery for Transonic Regional-Jet Wing through Multidisciplinary Design Exploration

    NASA Astrophysics Data System (ADS)

    Chiba, Kazuhisa; Obayashi, Shigeru; Morino, Hiroyuki

    Data mining is an important facet of solving multi-objective optimization problem. Because it is one of the effective manner to discover the design knowledge in the multi-objective optimization problem which obtains large data. In the present study, data mining has been performed for a large-scale and real-world multidisciplinary design optimization (MDO) to provide knowledge regarding the design space. The MDO among aerodynamics, structures, and aeroelasticity of the regional-jet wing was carried out using high-fidelity evaluation models on the adaptive range multi-objective genetic algorithm. As a result, nine non-dominated solutions were generated and used for tradeoff analysis among three objectives. All solutions evaluated during the evolution were analyzed for the tradeoffs and influence of design variables using a self-organizing map to extract key features of the design space. Although the MDO results showed the inverted gull-wings as non-dominated solutions, one of the key features found by data mining was the non-gull wing geometry. When this knowledge was applied to one optimum solution, the resulting design was found to have better performance compared with the original geometry designed in the conventional manner.

  11. The Effects of Surface Waviness and of Rib Stitching on Wing Drag

    NASA Technical Reports Server (NTRS)

    Hood, Manley J

    1939-01-01

    Surface waviness and rib stitching have been investigated as part of a series of tests to determine the effects on wing drag of common surface irregularities. The tests were made in the N.A.C.A. 8-foot high-speed wind tunnel at Reynolds Numbers up to 17,000,000. The results of the tests showed that the waviness common to airplane wings will cause no serious increase in drag unless the waviness exists on the forward part of the wing, where it may cause premature transition or premature compressibility effects. Waves 3 inches wide and 0.048 inch high, for example, increased the drag 1 percent when they covered the rear 67 percent of both surfaces and 10 percent when they covered the rear 92 percent. A single wave 3 inches wide and only 0.020 inch high at the 10.5-percent-chord point on the upper surface caused transition to occur on the wave and increased the drag 6 percent. Rib stitching increased the drag 7 percent when the rib spacing was 6 inches; the drag increment was proportional to the number of ribs for wider spacings. About one-third of the increase was due to premature transition at the forward ends of the stitching.

  12. Origin and diversification of wings: Insights from a neopteran insect

    PubMed Central

    Medved, Victor; Marden, James H.; Fescemyer, Howard W.; Der, Joshua P.; Liu, Jin; Mahfooz, Najmus; Popadić, Aleksandar

    2015-01-01

    Winged insects underwent an unparalleled evolutionary radiation, but mechanisms underlying the origin and diversification of wings in basal insects are sparsely known compared with more derived holometabolous insects. In the neopteran species Oncopeltus fasciatus, we manipulated wing specification genes and used RNA-seq to obtain both functional and genomic perspectives. Combined with previous studies, our results suggest the following key steps in wing origin and diversification. First, a set of dorsally derived outgrowths evolved along a number of body segments including the first thoracic segment (T1). Homeotic genes were subsequently co-opted to suppress growth of some dorsal flaps in the thorax and abdomen. In T1 this suppression was accomplished by Sex combs reduced, that when experimentally removed, results in an ectopic T1 flap similar to prothoracic winglets present in fossil hemipteroids and other early insects. Global gene-expression differences in ectopic T1 vs. T2/T3 wings suggest that the transition from flaps to wings required ventrally originating cells, homologous with those in ancestral arthropod gill flaps/epipods, to migrate dorsally and fuse with the dorsal flap tissue thereby bringing new functional gene networks; these presumably enabled the T2/T3 wing’s increased size and functionality. Third, “fused” wings became both the wing blade and surrounding regions of the dorsal thorax cuticle, providing tissue for subsequent modifications including wing folding and the fit of folded wings. Finally, Ultrabithorax was co-opted to uncouple the morphology of T2 and T3 wings and to act as a general modifier of hindwings, which in turn governed the subsequent diversification of lineage-specific wing forms. PMID:26668365

  13. Application of the joined wing to tiltrotor aircraft

    NASA Technical Reports Server (NTRS)

    Wolkovitch, Julian; Wainfan, Barnaby; Ben-Harush, Yitzhak; Johnson, Wayne

    1989-01-01

    A study was made to determine the potential speed improvements and other benefits resulting from the application of the joined wing concept to tiltrotor aircraft. Using the XV-15 as a baseline, the effect of replacing the cantilever wing by a joined-wing pair was studied. The baseline XV-15 cantilever wing has a thickness/chord ratio of 23 percent. It was found that this wing could be replaced by a joined-wing pair of the same span and total area employing airfoils of 12 percent thickness/chord ratio. The joined wing meets the same static strength requirements as the cantilever wing, but increases the limiting Mach Number of the aircraft from M=0.575 to M=0.75, equivalent to an increase of over 100 knots in maximum speed. The joined wing configuration studied is lighter than the cantilever and has approximately 11 percent less wing drag in cruise. Its flutter speed of 245 knots EAS is not high enough to allow the potential Mach number improvement to be attained at low altitude. The flutter speed can be raised either by employing rotors which can be stopped and folded in flight at speeds below 245 knots EAS, or by modifying the airframe to reduce adverse coupling with the rotor dynamics. Several modifications of wing geometry and nacelle mass distribution were investigated, but none produced a flutter speed above 260 knots EAS. It was concluded that additional research is required to achieve a more complete understanding of the mechanism of rotor/wing coupling.

  14. A four-wing chaotic attractor and its circuit implementation

    NASA Astrophysics Data System (ADS)

    van Wyk, M. A.; Qi, G.; van Wyk, B. J.

    2008-02-01

    By introducing a state feedback control to a proposed four dimensional chaotic system, an extremely complex four-wing chaotic attractor is derived having larger positive Lyapunov Exponent (LE) than other chaotic systems. Spectral analysis shows that the system in the four-wing chaotic mode has very broad frequency bandwidth, verifying its random nature, and indicating the prospect for engineering applications such as secure communications. Finally, an analog circuit, implementing the new four-wing chaotic system, is presented.

  15. Interference of multiplane wings having elliptical lift distribution

    NASA Technical Reports Server (NTRS)

    Von Sanden, H

    1924-01-01

    In calculating the self-induction of a wing surface, elliptical lift distribution is assumed, while in calculating the mutual induction or interference of two wing surfaces, a uniform distribution of the lift along the wing has hitherto been assumed. Whether the results of these calculations are substantially altered by assuming an elliptical lift distribution (which is just as probable as uniform distribution) is examined here.

  16. Biomechanical basis of wing and haltere coordination in flies

    PubMed Central

    Deora, Tanvi; Singh, Amit Kumar; Sane, Sanjay P.

    2015-01-01

    The spectacular success and diversification of insects rests critically on two major evolutionary adaptations. First, the evolution of flight, which enhanced the ability of insects to colonize novel ecological habitats, evade predators, or hunt prey; and second, the miniaturization of their body size, which profoundly influenced all aspects of their biology from development to behavior. However, miniaturization imposes steep demands on the flight system because smaller insects must flap their wings at higher frequencies to generate sufficient aerodynamic forces to stay aloft; it also poses challenges to the sensorimotor system because precise control of wing kinematics and body trajectories requires fast sensory feedback. These tradeoffs are best studied in Dipteran flies in which rapid mechanosensory feedback to wing motor system is provided by halteres, reduced hind wings that evolved into gyroscopic sensors. Halteres oscillate at the same frequency as and precisely antiphase to the wings; they detect body rotations during flight, thus providing feedback that is essential for controlling wing motion during aerial maneuvers. Although tight phase synchrony between halteres and wings is essential for providing proper timing cues, the mechanisms underlying this coordination are not well understood. Here, we identify specific mechanical linkages within the thorax that passively mediate both wing–wing and wing–haltere phase synchronization. We demonstrate that the wing hinge must possess a clutch system that enables flies to independently engage or disengage each wing from the mechanically linked thorax. In concert with a previously described gearbox located within the wing hinge, the clutch system enables independent control of each wing. These biomechanical features are essential for flight control in flies. PMID:25605915

  17. MTR OFFICE WINGS AT WEST SIDE OF MTR HIGH BAY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR OFFICE WINGS AT WEST SIDE OF MTR HIGH BAY REACTOR BUILDING. CONTEXTUAL VIEW. CAMERA FACING NORTHEAST. FROM LEFT TO RIGHT, TRA-652 (OFFICE WING), TRA-661 (SOUTH WING EXTENSION), SECOND/THIRD FLOOR (BALCONIES) OF MTR-603, MTR HIGH-BAY. AT RIGHT EDGE OF VIEW IS REACTOR SERVICES BUILDING (TRA-635). INL NEGATIVE NO. HD46-44-1. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  18. A blue-winged teal swims in the waters of KSC

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This male blue-winged teal is one of 23 species of migratory waterfowl that winter in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. The male is usually identified with pale blue shoulder patches and a white crescent in front of its eye. The blue-winged teal's normal range is from Canada to North Carolina, the Gulf Coast and southern California, preferring marshes, shallow ponds and lakes. It winters as far as northern South America. The refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

  19. 6. ANOTHER GRANDSTAND ENTRANCE, EAST WING OF GRANDSTAND. NOTE PHILADELPHIA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. ANOTHER GRANDSTAND ENTRANCE, EAST WING OF GRANDSTAND. NOTE PHILADELPHIA ATHLETICS'S LETTER 'A' ON CARTOUCHE. - Shibe Park (Stadium), 2701 North Twenty-first Street, Philadelphia, Philadelphia County, PA

  20. Experimental measurements of skin friction on upper surface blown wing

    NASA Technical Reports Server (NTRS)

    Miner, D. D.; Campbell, J. F.

    1975-01-01

    An experimental investigation was conducted to obtain skin-friction measurements on a wing with a circular jet exhausting above it. A Preston tube was used to determine the local shear stress at a point on the wing's upper surface. Data were obtained for four nozzle pressures and four vertical displacements of the jet above the wing. The results indicated that the highest skin-friction values occurred with the jet closest to the wing and with the highest nozzle pressure. These data trends were validated by calculations which combined two-dimensional, turbulent boundary-layer theory with axisymmetric co-flowing jet theory.