Military Potential Test of the UH-2A Helicopter.

DTIC Science & Technology

1963-10-25

required to fully service two engines during engine change. 3. One quart of hydr aulic fluid , MIL 5606. Used to replace spillage while disconnecting...Maryland , dated 24 January 1963. 7. Report Nr. 1, Final Report, Climatic Laboratory Environ- mental Test of the Model UH- 2A Helicopter , by US

Ground shake test of the UH-60A helicopter airframe and comparison with NASTRAN finite element model predictions

NASA Technical Reports Server (NTRS)

Howland, G. R.; Durno, J. A.; Twomey, W. J.

1990-01-01

Sikorsky Aircraft, together with the other major helicopter airframe manufacturers, is engaged in a study to improve the use of finite element analysis to predict the dynamic behavior of helicopter airframes, under a rotorcraft structural dynamics program called DAMVIBS (Design Analysis Methods for VIBrationS), sponsored by the NASA-Langley. The test plan and test results are presented for a shake test of the UH-60A BLACK HAWK helicopter. A comparison is also presented of test results with results obtained from analysis using a NASTRAN finite element model.

UH-60 Airloads Program Tutorial

NASA Technical Reports Server (NTRS)

Bousman, William G.

2009-01-01

From the fall of 1993 to late winter of 1994, NASA Ames and the U.S. Army flew a flight test program using a UH-60A helicopter with extensive instrumentation on the rotor and blades, including 242 pressure transducers. Over this period, approximately 30 flights were made, and data were obtained in level flight, maneuver, ascents, and descents. Coordinated acoustic measurements were obtained with a ground-acoustic array in cooperation with NASA Langley, and in-flight acoustic measurements with a YO-3A aircraft. NASA has sponsored the creation of a "tutorial' which covers the depth and breadth of the flight test program with a mixture of text and graphics. The primary purpose of this tutorial is to introduce the student to what is known about rotor aerodynamics based on the UH-60A measurements. The tutorial will also be useful to anyone interested in helicopters who would like to have more detailed knowledge about helicopter aerodynamics.

UH-1 Helicopter Mechanic (MOS 67N20) Job Description Survey: Performance of Specific Maintenance Tasks.

ERIC Educational Resources Information Center

Schulz, Russel E.; And Others

The report is the second of two describing the results of a world-wide survey of the maintenance activities of UH-1 helicopter mechanics for the purpose of studying the relationships among job requirements, training, and manpower considerations for aviation maintenance. A summary of the results of the first report is included. The survey…

UH-1 Helicopter Mechanic (MOS 67N20) Job Description Survey: Background, Training, and General Maintenance Activities.

ERIC Educational Resources Information Center

Schulz, Russel E.; And Others

The report, the first of two documents examining the relationship among job requirements, training, and manpower considerations for Army aviation maintenance Personnel, discusses the development of task data gathering techniques and procedures for incorporating this data into training programs for the UH-1 helicopter mechanic sPecialty (MOS…

Fidelity assessment of a UH-60A simulation on the NASA Ames vertical motion simulator

NASA Technical Reports Server (NTRS)

Atencio, Adolph, Jr.

1993-01-01

Helicopter handling qualities research requires that a ground-based simulation be a high-fidelity representation of the actual helicopter, especially over the frequency range of the investigation. This experiment was performed to assess the current capability to simulate the UH-60A Black Hawk helicopter on the Vertical Motion Simulator (VMS) at NASA Ames, to develop a methodology for assessing the fidelity of a simulation, and to find the causes for lack of fidelity. The approach used was to compare the simulation to the flight vehicle for a series of tasks performed in flight and in the simulator. The results show that subjective handling qualities ratings from flight to simulator overlap, and the mathematical model matches the UH-60A helicopter very well over the range of frequencies critical to handling qualities evaluation. Pilot comments, however, indicate a need for improvement in the perceptual fidelity of the simulation in the areas of motion and visual cuing. The methodology used to make the fidelity assessment proved useful in showing differences in pilot work load and strategy, but additional work is needed to refine objective methods for determining causes of lack of fidelity.

Flight tests of IFR landing approach systems for helicopters

NASA Technical Reports Server (NTRS)

Bull, J. S.; Hegarty, D. M.; Peach, L. L.; Phillips, J. D.; Anderson, D. J.; Dugan, D. C.; Ross, V. L.

1981-01-01

Joint NASA/FAA helicopter flight tests were conducted to investigate airborne radar approaches (ARA) and microwave landing system (MLS) approaches. Flight-test results were utilized to prove NASA with a data base to be used as a performance measure for advanced guidance and navigation concepts, and to provide FAA with data for establishment of TERPS criteria. The first flight-test investigation consisted of helicopter IFR approaches to offshore oil rigs in the Gulf of Mexico, using weather/mapping radar, operational pilots, and a Bell 212 helicopter. The second flight-test investigation consisted of IFR MLS approaches at Crows Landing (near Ames Research Center), with a Bell UH-1H helicopter, using NASA, FAA, and operational industry pilots. Tests are described and results discussed.

Comparison of NASTRAN analysis with ground vibration results of UH-60A NASA/AEFA test configuration

NASA Technical Reports Server (NTRS)

Idosor, Florentino; Seible, Frieder

1990-01-01

Preceding program flight tests, a ground vibration test and modal test analysis of a UH-60A Black Hawk helicopter was conducted by Sikorsky Aircraft to complement the UH-60A test plan and NASA/ARMY Modern Technology Rotor Airloads Program. The 'NASA/AEFA' shake test configuration was tested for modal frequencies and shapes and compared with its NASTRAN finite element model counterpart to give correlative results. Based upon previous findings, significant differences in modal data existed and were attributed to assumptions regarding the influence of secondary structure contributions in the preliminary NASTRAN modeling. An analysis of an updated finite element model including several secondary structural additions has confirmed that the inclusion of specific secondary components produces a significant effect on modal frequency and free-response shapes and improves correlations at lower frequencies with shake test data.

Navigation and flight director guidance for the NASA/FAA helicopter MLS curved approach flight test program

NASA Technical Reports Server (NTRS)

Phatak, A. V.; Lee, M. G.

1985-01-01

The navigation and flight director guidance systems implemented in the NASA/FAA helicopter microwave landing system (MLS) curved approach flight test program is described. Flight test were conducted at the U.S. Navy's Crows Landing facility, using the NASA Ames UH-lH helicopter equipped with the V/STOLAND avionics system. The purpose of these tests was to investigate the feasibility of flying complex, curved and descending approaches to a landing using MLS flight director guidance. A description of the navigation aids used, the avionics system, cockpit instrumentation and on-board navigation equipment used for the flight test is provided. Three generic reference flight paths were developed and flown during the test. They were as follows: U-Turn, S-turn and Straight-In flight profiles. These profiles and their geometries are described in detail. A 3-cue flight director was implemented on the helicopter. A description of the formulation and implementation of the flight director laws is also presented. Performance data and analysis is presented for one pilot conducting the flight director approaches.

Flight Test Identification and Simulation of a UH-60A Helicopter and Slung Load

NASA Technical Reports Server (NTRS)

Cicolani, Luigi S.; Sahai, Ranjana; Tucker, George E.; McCoy, Allen H.; Tyson, Peter H.; Tischler, Mark B.; Rosen, Aviv

2001-01-01

Helicopter slung-load operations are common in both military and civil contexts. Helicopters and loads are often qualified for these operations by means of flight tests, which can be expensive and time consuming. There is significant potential to reduce such costs both through revisions in flight-test methods and by using validated simulation models. To these ends, flight tests were conducted at Moffett Field to demonstrate the identification of key dynamic parameters during flight tests (aircraft stability margins and handling-qualities parameters, and load pendulum stability), and to accumulate a data base for simulation development and validation. The test aircraft was a UH-60A Black Hawk, and the primary test load was an instrumented 8- by 6- by 6-ft cargo container. Tests were focused on the lateral and longitudinal axes, which are the axes most affected by the load pendulum modes in the frequency range of interest for handling qualities; tests were conducted at airspeeds from hover to 80 knots. Using telemetered data, the dynamic parameters were evaluated in near real time after each test airspeed and before clearing the aircraft to the next test point. These computations were completed in under 1 min. A simulation model was implemented by integrating an advanced model of the UH-60A aerodynamics, dynamic equations for the two-body slung-load system, and load static aerodynamics obtained from wind-tunnel measurements. Comparisons with flight data for the helicopter alone and with a slung load showed good overall agreement for all parameters and test points; however, unmodeled secondary dynamic losses around 2 Hz were found in the helicopter model and they resulted in conservative stability margin estimates.

Helicopter noise measurements data report. volume II. helicopter models: Bell 212 (UH-1N), Sikorsky S-61 (SH-3A), Sikorsky S-64 'Skycrane' (CH- 54B), Boeing Vertol 'Chinook' (CH-47C)

DOT National Transportation Integrated Search

1977-04-01

The helicopter models used in this test program were the Hughes 300C, Hughes 500C, Bell 47-G, Bell 206-L, Bell 212 (UH-1N), Sikorsky S-61 (SH-3A), Sikorsky S-64 'Skycrane' (CH-54B), and Boeing Vertol 'Chinook' CH-47C. Volume I contains the measured n...

NASA/UH signing of memorandum of understanding

NASA Image and Video Library

1996-10-02

NASA/University of Houston (UH) signing of memorandum of understanding. Johnson Space Center (JSC) Director George Abbey signs a memorandum of understanding with University of Houston's President Glenn Goerke and University of Houston Clear Lake President Williams Staples. UH will supply post-doctoral researchers to JSC for more than 15 projects of scientific interest to both JSC and the university. Seated from left are, Abbey, Goerke and Staples. Standing from left are David Criswell, director of the Institute of Space Systems Operations; Texas State Representatives Michael Jackson, Robert Talton and Talmadge Heflin. View appears in Space News Roundup v35 n41 p4, 10-18-96.

KSC00pp1789

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers get ready to move a NASA UH-1H helicopter outside. They have been painting the blades of four NASA UH-1H helicopters, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire contro

KSC-00pp1789

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers get ready to move a NASA UH-1H helicopter outside. They have been painting the blades of four NASA UH-1H helicopters, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire contro

KSC00pp1790

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA UH-1H helicopter is prepared for transfer back to Patrick Air Force Base after being painted. The blades of four NASA UH-1H helicopters were repainted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1790

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA UH-1H helicopter is prepared for transfer back to Patrick Air Force Base after being painted. The blades of four NASA UH-1H helicopters were repainted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

Gear tooth stress measurements on the UH-60A helicopter transmission

NASA Technical Reports Server (NTRS)

Oswald, Fred B.

1987-01-01

The U.S. Army UH-60A (Black Hawk) 2200-kW (3000-hp) class twin-engine helicopter transmission was tested at the NASA Lewis Research Center. Results from these experimental (strain-gage) stress tests will enhance the data base for gear stress levels in transmissions of a similar power level. Strain-gage measurements were performed on the transmission's spiral-bevel combining pinions, the planetary Sun gear, and ring gear. Tests were performed at rated speed and at torque levels 25 to 100 percent that of rated. One measurement series was also taken at a 90 percent speed level. The largest stress found was 760 MPa (110 ksi) on the combining pinion fillet. This is 230 percent greater than the AGMA index stress. Corresponding mean and alternating stresses were 300 and 430 MPa (48 and 62 ksi). These values are within the range of successful test experience reported for other transmissions. On the fillet of the ring gear, the largest stress found was 410 MPa (59 ksi). The ring-gear peak stress was found to be 11 percent less than an analytical (computer simulation) value and it is 24 percent greater than the AGMA index stress. A peak compressive stress of 650 MPa (94 ksi) was found at the center of the Sun gear tooth root.

Effect of advanced component technology on helicopter transmissions

NASA Technical Reports Server (NTRS)

Lewicki, David G.; Townsend, Dennis P.

1989-01-01

Experimental tests were performed on the NASA/Bell Helicopter Textron (BHT) 500 hp advanced technology transmission (ATT) at the NASA Lewis Research Center. The ATT was a retrofit of the OH-58C helicopter 236 kW (317 hp) main rotor transmission, upgraded to 373 kW (500 hp), with a design goal of retaining long life with a minimum increase in cost, weight, and size. Vibration, strain, efficiency, deflection, and temperature experiments were performed and the results were compared to previous experiments on the OH-58A, OH-58C, and UH-60A transmissions. The high-contact-ratio gears and the cantilevered-mounted, flexible ring gear of the ATT reduced vibration compared to that of the OH-58C. The ATT flexible ring gear improved planetary load sharing compared to that of the rigid ring gear of the UH-60A transmission. The ATT mechanical efficiency was lower than that of the OH-58A transmission, probably due to the high-contact-ratio planetary gears.

Piloted Evaluation of a UH-60 Mixer Equivalent Turbulence Simulation Model

NASA Technical Reports Server (NTRS)

Lusardi, Jeff A.; Blanken, Chris L.; Tischeler, Mark B.

2002-01-01

A simulation study of a recently developed hover/low speed Mixer Equivalent Turbulence Simulation (METS) model for the UH-60 Black Hawk helicopter was conducted in the NASA Ames Research Center Vertical Motion Simulator (VMS). The experiment was a continuation of previous work to develop a simple, but validated, turbulence model for hovering rotorcraft. To validate the METS model, two experienced test pilots replicated precision hover tasks that had been conducted in an instrumented UH-60 helicopter in turbulence. Objective simulation data were collected for comparison with flight test data, and subjective data were collected that included handling qualities ratings and pilot comments for increasing levels of turbulence. Analyses of the simulation results show good analytic agreement between the METS model and flight test data, with favorable pilot perception of the simulated turbulence. Precision hover tasks were also repeated using the more complex rotating-frame SORBET (Simulation Of Rotor Blade Element Turbulence) model to generate turbulence. Comparisons of the empirically derived METS model with the theoretical SORBET model show good agreement providing validation of the more complex blade element method of simulating turbulence.

Adaptive Neuro-Fuzzy Modeling of UH-60A Pilot Vibration

NASA Technical Reports Server (NTRS)

Kottapalli, Sesi; Malki, Heidar A.; Langari, Reza

2003-01-01

Adaptive neuro-fuzzy relationships have been developed to model the UH-60A Black Hawk pilot floor vertical vibration. A 200 point database that approximates the entire UH-60A helicopter flight envelope is used for training and testing purposes. The NASA/Army Airloads Program flight test database was the source of the 200 point database. The present study is conducted in two parts. The first part involves level flight conditions and the second part involves the entire (200 point) database including maneuver conditions. The results show that a neuro-fuzzy model can successfully predict the pilot vibration. Also, it is found that the training phase of this neuro-fuzzy model takes only two or three iterations to converge for most cases. Thus, the proposed approach produces a potentially viable model for real-time implementation.

BOREAS RSS-3 Reflectance Measured from a Helicopter-Mounted SE-590

NASA Technical Reports Server (NTRS)

Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Walthall, Charles L.; Loechel, Sara

2000-01-01

The BOREAS RSS-3 team collected multiple remotely sensed data sets from the NASA UH-1 helicopter. This data set includes helicopter-based radiometric measurements of forested sites acquired during BOREAS made with an SE-590 processed to reflectance factors. The data used in this analysis were collected in 1994 during the three BOREAS IFCs at numerous tower and auxiliary sites in both the NSA and the SSA. The 15-degree FOV of the SE-590 yielded a ground resolution of approximately 79 m at the 300-m nominal altitude. The data are provided in tabular ASCII files.

Helicopter Approach Capability Using the Differential Global Positioning System

NASA Technical Reports Server (NTRS)

Kaufmann, David N.

1994-01-01

The results of flight tests to determine the feasibility of using the Global Positioning System (GPS) in the Differential mode (DGPS) to provide high accuracy, precision navigation and guidance for helicopter approaches to landing are presented. The airborne DGPS receiver and associated equipment is installed in a NASA UH-60 Black Hawk helicopter. The ground-based DGPS reference receiver is located at a surveyed test site and is equipped with a real-time VHF data link to transmit correction information to the airborne DGPS receiver. The corrected airborne DGPS information, together with the preset approach geometry, is used to calculate guidance commands which are sent to the aircraft's approach guidance instruments. The use of DGPS derived guidance for helicopter approaches to landing is evaluated by comparing the DGPS data with the laser tracker truth data. The errors indicate that the helicopter position based on DGPS guidance satisfies the International Civil Aviation Organization (ICAO) Category 1 (CAT 1) lateral and vertical navigational accuracy requirements.

Flight Testing and Real-Time System Identification Analysis of a UH-60A Black Hawk Helicopter with an Instrumented External Sling Load

NASA Technical Reports Server (NTRS)

McCoy, Allen H.

1998-01-01

Helicopter external air transportation plays an important role in today's world. For both military and civilian helicopters, external sling load operations offer an efficient and expedient method of handling heavy, oversized cargo. With the ability to reach areas otherwise inaccessible by ground transportation, helicopter external load operations are conducted in industries such as logging, construction, and fire fighting, as well as in support of military tactical transport missions. Historically, helicopter and load combinations have been qualified through flight testing, requiring considerable time and cost. With advancements in simulation and flight test techniques there is potential to substantially reduce costs and increase the safety of helicopter sling load certification. Validated simulation tools make possible accurate prediction of operational flight characteristics before initial flight tests. Real time analysis of test data improves the safety and efficiency of the testing programs. To advance these concepts, the U.S. Army and NASA, in cooperation with the Israeli Air Force and Technion, under a Memorandum of Agreement, seek to develop and validate a numerical model of the UH-60 with sling load and demonstrate a method of near real time flight test analysis. This thesis presents results from flight tests of a U.S. Army Black Hawk helicopter with various external loads. Tests were conducted as the U.S. first phase of this MOA task. The primary load was a container express box (CONEX) which contained a compact instrumentation package. The flights covered the airspeed range from hover to 70 knots. Primary maneuvers were pitch and roll frequency sweeps, steps, and doublets. Results of the test determined the effect of the suspended load on both the aircraft's handling qualities and its control system's stability margins. Included were calculations of the stability characteristics of the load's pendular motion. Utilizing CIFER(R) software, a method for near

NASA helicopter transmission system technology program

NASA Technical Reports Server (NTRS)

Zaretsky, E. V.

1983-01-01

The purpose of the NASA Helicopter Transmission System Technology Program is to improve specific mechanical components and the technology for combining these into advanced drive systems to make helicopters more viable and cost competitive for commerical applications. The history, goals, and elements of the program are discussed.

Flight-test experience of a helicopter encountering an airplane trailing vortex

NASA Technical Reports Server (NTRS)

Dunham, R. E., Jr.; Holbrook, G. T.; Campbell, R. L.; Van Gunst, R. W.; Mantay, W. R.

1976-01-01

This paper presents results of a flight-test experiment of a UH-1H helicopter encountering the vortex wake of a C-54 airplane. The helicopter was instrumented to record the pilot control inputs, determine the upset experience, and measure critical loads within the rotor system. During the flight-test program 132 penetrations of the vortex wake were made by the helicopter at separation distances from 3/8 to 6-1/2 nautical miles. Test results indicated that the helicopter upsets and the vortex induced blade loads experienced were minimal and well within safe limits. The upsets were very mild when compared to a typical response of a small airplane to the vortex wake of the C-54 airplane.

Helicopter flight-control design using an H(2) method

NASA Technical Reports Server (NTRS)

Takahashi, Marc D.

1991-01-01

Rate-command and attitude-command flight-control designs for a UH-60 helicopter in hover are presented and were synthesized using an H(2) method. Using weight functions, this method allows the direct shaping of the singular values of the sensitivity, complementary sensitivity, and control input transfer-function matrices to give acceptable feedback properties. The designs were implemented on the Vertical Motion Simulator, and four low-speed hover tasks were used to evaluate the control system characteristics. The pilot comments from the accel-decel, bob-up, hovering turn, and side-step tasks indicated good decoupling and quick response characteristics. However, an underlying roll PIO tendency was found to exist away from the hover condition, which was caused by a flap regressing mode with insufficient damping.

Development in helicopter tail boom strake applications in the US

NASA Technical Reports Server (NTRS)

Wilson, John C.; Kelley, Henry L.; Donahue, Cynthia C.; Yenni, Kenneth R.

1988-01-01

The use of a strake or spoiler on a helicopter tail boom to beneficially change helicopter tail boom air loads was suggested in the United States in 1975. The anticipated benefits were a change of tail boom loads to reduce required tail rotor thrust and power and improve directional control. High tail boom air loads experienced by the YAH-64 and described in 1978 led to a wind tunnel investigation of the usefullness of strakes in altering such loads on the AH-64, UH-60, and UH-1 helicopters. The wind tunnel tests of 2-D cross sections of the tail boom of each demonstrated that a strake or strakes would be effective. Several limited test programs with the U.S. Army's OH-58A, AH-64, and UH-60A were conducted which showed the effects of strakes were modest for those helicopters. The most recent flight test program, with a Bell 204B, disclosed that for the 204B the tail boom strake or strakes would provide more than a modest improvement in directional control and reduction in tail rotor power.

Flight-Time Identification of a UH-60A Helicopter and Slung Load

NASA Technical Reports Server (NTRS)

Cicolani, Luigi S.; McCoy, Allen H.; Tischler, Mark B.; Tucker, George E.; Gatenio, Pinhas; Marmar, Dani

1998-01-01

This paper describes a flight test demonstration of a system for identification of the stability and handling qualities parameters of a helicopter-slung load configuration simultaneously with flight testing, and the results obtained.Tests were conducted with a UH-60A Black Hawk at speeds from hover to 80 kts. The principal test load was an instrumented 8 x 6 x 6 ft cargo container. The identification used frequency domain analysis in the frequency range to 2 Hz, and focussed on the longitudinal and lateral control axes since these are the axes most affected by the load pendulum modes in the frequency range of interest for handling qualities. Results were computed for stability margins, handling qualities parameters and load pendulum stability. The computations took an average of 4 minutes before clearing the aircraft to the next test point. Important reductions in handling qualities were computed in some cases, depending, on control axis and load-slung combination. A database, including load dynamics measurements, was accumulated for subsequent simulation development and validation.

Effects of Microclimate Cooling on Physiology and Performance While Flying the UH-60 Helicopter Simulator in NBC Conditions in a Controlled Heat Environment

DTIC Science & Technology

1992-08-01

including instrumenting and dressing the subjects, monitoring the physiological parameters in the simulator, and collecting and processing data. They...also was decided to extend the recruiting process to include all helicopter aviators, even if not UH-60 qualified. There is little in the flight profile...parameter channels, and the data were processed to produce a single root mean square (RMS) error value for each channel appropriate to each of the 9

CAA modeling of helicopter main rotor in hover

NASA Astrophysics Data System (ADS)

Kusyumov, Alexander N.; Mikhailov, Sergey A.; Batrakov, Andrey S.; Kusyumov, Sergey A.; Barakos, George

In this work rotor aeroacoustics in hover is considered. Farfield observers are used and the nearfield flow parameters are obtained using the in house HMB and commercial Fluent CFD codes (identical hexa-grids are used for both solvers). Farfield noise at a remote observer position is calculated at post processing stage using FW-H solver implemented in Fluent and HMB. The main rotor of the UH-1H helicopter is considered as a test case for comparison to experimental data. The sound pressure level is estimated for different rotor blade collectives and observation angles.

KSC00pp1791

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A newly repainted NASA helicopter is transported to S.R. 3 for return to Patrick AFB. Workers painted the blades of four NASA UH-1H helicopters, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1791

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A newly repainted NASA helicopter is transported to S.R. 3 for return to Patrick AFB. Workers painted the blades of four NASA UH-1H helicopters, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

Helicopter payload gains utilizing water injection for hot day power augmentation

NASA Technical Reports Server (NTRS)

Stroub, R. H.

1972-01-01

An analytical investigation was undertaken to assess the gains in helicopter mission payload through the use of water injection to produce power augmentation in an altitude-hot day environment. Substantial gains are shown for two representative helicopters, the UH-lH and CH-47B. The UH-lH payload increased 86.7 percent for a 50 n.mi. (92.6 km) radius mission involving two out-of-ground effect (OGE) hover take-offs of 2 minutes each at 5000 ft. (1525 m) 35 C ambient conditions. The CH-47B payload increased 49.5 percent for a 50 n.mi. (92.6 km) radius mission with sling loaded cargo as the outbound payload and a 3000 lb. (1360 kg) internal cargo on the return leg. The mission included two 4 min. OGE hovers at 6000 ft. (1830 m) 35 C. An improvement in take off performance and maximum performance climb also resulted as a consequence of the OGE hover capability and higher maximum power available.

Sensitivity analysis of helicopter IMC decelerating steep approach and landing performance to navigation system parameters

NASA Technical Reports Server (NTRS)

Karmali, M. S.; Phatak, A. V.

1982-01-01

Results of a study to investigate, by means of a computer simulation, the performance sensitivity of helicopter IMC DSAL operations as a function of navigation system parameters are presented. A mathematical model representing generically a navigation system is formulated. The scenario simulated consists of a straight in helicopter approach to landing along a 6 deg glideslope. The deceleration magnitude chosen is 03g. The navigation model parameters are varied and the statistics of the total system errors (TSE) computed. These statistics are used to determine the critical navigation system parameters that affect the performance of the closed-loop navigation, guidance and control system of a UH-1H helicopter.

NASA/FAA helicopter simulator workshop

NASA Technical Reports Server (NTRS)

Larsen, William E. (Editor); Randle, Robert J., Jr. (Editor); Bray, Richard S. (Editor); Zuk, John (Editor)

1992-01-01

A workshop was convened by the FAA and NASA for the purpose of providing a forum at which leading designers, manufacturers, and users of helicopter simulators could initiate and participate in a development process that would facilitate the formulation of qualification standards by the regulatory agency. Formal papers were presented, special topics were discussed in breakout sessions, and a draft FAA advisory circular defining specifications for helicopter simulators was presented and discussed. A working group of volunteers was formed to work with the National Simulator Program Office to develop a final version of the circular. The workshop attracted 90 individuals from a constituency of simulator manufacturers, training organizations, the military, civil regulators, research scientists, and five foreign countries.

KSC00pp1786

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers paint the blades of a NASA UH-1H helicopter, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1787

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers paint the blades of a NASA UH-1H helicopter, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1786

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers paint the blades of a NASA UH-1H helicopter, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1787

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers paint the blades of a NASA UH-1H helicopter, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1798

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- At S.R. 3 a NASA helicopter returns to Patrick Air Force Base. The helicopter is one of four UH-1H helicopters that have had its blades painted, changing the previous black color to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1798

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- At S.R. 3 a NASA helicopter returns to Patrick Air Force Base. The helicopter is one of four UH-1H helicopters that have had its blades painted, changing the previous black color to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1797

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- At S.R. 3 a NASA helicopter lifts off to return to Patrick Air Force Base. The helicopter is one of four UH-1H helicopters that have had its blades painted, changing the previous black color to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1797

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- At S.R. 3 a NASA helicopter lifts off to return to Patrick Air Force Base. The helicopter is one of four UH-1H helicopters that have had its blades painted, changing the previous black color to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

Tests with an integrated helmet system for the TIGER helicopter

NASA Astrophysics Data System (ADS)

Boehm, Hans-Dieter V.; Evers, Carl; Stenner, K.-H.

1998-08-01

The TIGER helicopter is under development by the MODs of France and Germany for their armies. The initial German requirement was for anti-tank missions only. This task has been extended to support missions which resulted in an upgrade to the German 'UH-TIGER' variant. German MOD is planning to procure 212 UH-TIGER helicopters armed with TRIGAT-, HOT anti-tank missiles, STINGER air-to-air missiles, 68 mm rockets and a gun pod with a 12.7 mm gun.

Helicopter Noise Definition Report UH-60A, S-76, A-109, 206-L

DTIC Science & Technology

1981-12-01

ALL THE WORLDS AIRCRAF~ 25 -.. H., . . . I - I’I Fi.I 2.3. Sikrsk UH .0A "Bla *khaw -" | r a’ Fig. 2.3.2 Sikoraky S-76, "Spirit" -. q A,~ ~ j A. "I...1305 1:2 -04830 8545 82+9 75*1 O1,6 87,b Sete 11,5 10s5 1#2 -1*0 31 85.7 83,3 75,1 80.0 86#6 67,7 16#5 150 1#1 -0#7 32 83.7 81.2 73.5 79.3 85,6 8669...RIO. TIMITIKE PNLTP WAR REOORDED RAOD TIMiTIME PNLTM WAS RADIATED R/OlAIORAFT RPATE OLI•ND OR DS6ENT O’D-ANGtOL•IM OR DESCENT ANGE.E G*6GROUND SPEED

A model-based analysis of a display for helicopter landing approach. [control theoretical model of human pilot

NASA Technical Reports Server (NTRS)

Hess, R. A.; Wheat, L. W.

1975-01-01

A control theoretic model of the human pilot was used to analyze a baseline electronic cockpit display in a helicopter landing approach task. The head down display was created on a stroke written cathode ray tube and the vehicle was a UH-1H helicopter. The landing approach task consisted of maintaining prescribed groundspeed and glideslope in the presence of random vertical and horizontal turbulence. The pilot model was also used to generate and evaluate display quickening laws designed to improve pilot vehicle performance. A simple fixed base simulation provided comparative tracking data.

Helicopter simulation validation using flight data

NASA Technical Reports Server (NTRS)

Key, D. L.; Hansen, R. S.; Cleveland, W. B.; Abbott, W. Y.

1982-01-01

A joint NASA/Army effort to perform a systematic ground-based piloted simulation validation assessment is described. The best available mathematical model for the subject helicopter (UH-60A Black Hawk) was programmed for real-time operation. Flight data were obtained to validate the math model, and to develop models for the pilot control strategy while performing mission-type tasks. The validated math model is to be combined with motion and visual systems to perform ground based simulation. Comparisons of the control strategy obtained in flight with that obtained on the simulator are to be used as the basis for assessing the fidelity of the results obtained in the simulator.

KSC00pp1788

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers put the finishing touches on new paint for the blades of a NASA UH-1H helicopter. They have changed the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen from above by a second helicopter. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1788

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- Workers put the finishing touches on new paint for the blades of a NASA UH-1H helicopter. They have changed the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen from above by a second helicopter. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1793

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA helicopter lands on S.R. 3 for transfer to Patrick Air Force Base. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1793

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA helicopter lands on S.R. 3 for transfer to Patrick Air Force Base. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1792

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA helicopter from Patrick Air Force Base is about to land on S.R. 3. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1792

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA helicopter from Patrick Air Force Base is about to land on S.R. 3. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1795

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA helicopter is secured for transfer to Ransom Road at KSC. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1795

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- A NASA helicopter is secured for transfer to Ransom Road at KSC. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

NASA helicopter helps fight fire at KSC

NASA Technical Reports Server (NTRS)

2000-01-01

A NASA helicopter drops water from a special '''bucket''' onto a small fire on Kennedy Space Center grounds. The site is between Kennedy Parkway North and the Indian River. The fire is one of many throughout Central Florida, which is suffering from drought.

NASA helicopter helps fight fire at KSC

NASA Technical Reports Server (NTRS)

2000-01-01

A NASA helicopter takes off to bring water to fight a small fire on Kennedy Space Center grounds. The site is between Kennedy Parkway North and the Indian River. The fire is one of many throughout Central Florida, which is suffering from drought.

KSC-00pp1796

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- At S.R. 3 a pilot prepares a NASA helicopter for a return flight to Patrick Air Force Base. The helicopter is one of four UH-1H helicopters that have had its blades painted, changing the previous black color to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC00pp1796

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- At S.R. 3 a pilot prepares a NASA helicopter for a return flight to Patrick Air Force Base. The helicopter is one of four UH-1H helicopters that have had its blades painted, changing the previous black color to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

Does modern helicopter construction reduce noise exposure in helicopter rescue operations?

PubMed

Küpper, Thomas; Jansing, Paul; Schöffl, Volker; van Der Giet, Simone

2013-01-01

During helicopter rescue operations the medical personnel are at high risk for hearing damage by noise exposure. There are two important factors to be taken into account: first, the extreme variability, with some days involving no exposure but other days with extreme exposure; second, the extreme noise levels during work outside the helicopter, e.g. during winch operations. The benefit of modern, less noisier constructions and the consequences for noise protection are still unknown. We estimated the noise exposure of the personnel for different helicopter types used during rescue operations in the Alps and in other regions of the world with special regard to the advanced types like Eurocopter EC 135 to compare the benefit of modern constructions for noise protection with earlier ones. The rescue operations over 1 year of four rescue bases in the Alps (Raron and Zermatt in Switzerland; Landeck and Innsbruck in Austria, n = 2731) were analyzed for duration of rescue operations (noise exposure). Noise levels were measured during rescue operations at defined points inside and outside the different aircraft. The setting is according to the European standard (Richtlinie 2003/10/EG Amtsblatt) and to Class 1 DIN/IEC 651. With both data sets the equivalent noise level L(eq8h) was calculated. For comparison it was assumed that all rescue operations were performed with a specific type of helicopter. Then model calculations for noise exposure by different helicopter types, such as Alouette IIIb, Alouette II 'Lama', Ecureuil AS350, Bell UH1D, Eurocopter EC135, and others were performed. Depending on modern technologies the situation for the personnel has been improved significantly. Nevertheless noise prevention, which includes noise intermissions in spare time, is essential. Medical checks of the crews by occupational medicine (e.g. 'G20' in Germany) are still mandatory.

KSC00pp1794

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- The pilot of the NASA helicopter secures the rotary blade before the helicopter’s transfer to Ransom Road at KSC. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

KSC-00pp1794

NASA Image and Video Library

2000-10-25

KENNEDY SPACE CENTER, FLA. -- The pilot of the NASA helicopter secures the rotary blade before the helicopter’s transfer to Ransom Road at KSC. It is one of four UH-1H helicopters that will have its blades painted, changing the black to a pattern of white and yellow stripes. The pattern provides better visibility in smoke and fire conditions. When the rotors are turning, the stripes create a yellow and white circle that is more easily seen by a second helicopter from above. The helicopters, primarily used for security and medical evacuation for NASA, will be used to deliver water via buckets during brush fires. The change was made to comply with U.S. Fish and Wildlife and Department of Forestry regulations for helicopter-assisted fire control

State Estimation of Main Rotor Flap and Lead-Lag Using Accelerometers and Laser Transducers on the RASCAL UH-60 Helicopter

NASA Technical Reports Server (NTRS)

Fletcher, Jay W.; Chen, Robert T. N.; Strasilla, Eric; Aiken, Edwin W. (Technical Monitor)

1995-01-01

Modern rotorcraft flight control system designs which promise to yield high vehicle response bandwidth and good gust rejection can benefit from the use of rotor-state feedbacks. The measurement of main rotor blade motions is also desirable to validate and improve rotorcraft simulation models, to identify high-order linear flight dynamics models, to provide rotor system health monitoring; during flight test, and to provide for correlation with acoustic measurements from wind tunnel and flight tests. However, few attempts have been made to instrument a flight vehicle in this manner, and no previous system has had the robustness and accuracy required for these diverse applications. A rotor blade motion measurement and estimation system has been developed by NASA and the U.S. Army for use on the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) helicopter. RASCAL is a UH-60 Blackhawk which is being modified at Ames Research Center in a phased development program for use in flight dynamics and controls, navigation, airspace management, and rotorcraft human factors research. The aircraft will feature a full-authority, digital, fly-by-wire research flight control system; a coupled ring laser gyro, differential GPS based navigation system; a stereoscopic color wide field of view helmet, mounted display; programmable panel mounted displays; and advanced navigation sensors. The rotor blade motion system is currently installed for data acquisition only, but will be integrated with the research flight control system when it is installed later this year.

Airworthiness and Flight Characteristics Evaluation, UH-60A (Black Hawk) Helicopter

DTIC Science & Technology

1981-09-01

ACTIVITY EDWARDS AIR FORCE BASE, CALIFORNIA 93523 8..30 83 09 0 1 n 04 DISCLoAIMER NOTICE The findings of this report are not to be constrned as an...EDWARDS AIR FORCE BASE, CALIFORNJA 68-0-BH031.-01-68 II. CONTROLLING OFFICE NAME AND ADORESS 1I. REPORT OATS US ARMY AVN RESEARCH & DEVELOPMENT COMMAND...34| conipliance with the applicable paragraphs of the Prime Item Development Specification The UH-60A was tested at Edwards Air Force Base. California

Aeromechanics Analysis of a Compound Helicopter

NASA Technical Reports Server (NTRS)

Yeo, Hyeonsoo; Johnson, Wayne

2006-01-01

A design and aeromechanics investigation was conducted for a 100,000-lb compound helicopter with a single main rotor, which is to cruise at 250 knots at 4000 ft/95 deg F condition. Performance, stability, and control analyses were conducted with the comprehensive rotorcraft analysis CAMRAD II. Wind tunnel test measurements of the performance of the H-34 and UH-1D rotors at high advance ratio were compared with calculations to assess the accuracy of the analysis for the design of a high speed helicopter. In general, good correlation was obtained with the increase of drag coefficients in the reverse flow region. An assessment of various design parameters (disk loading, blade loading, wing loading) on the performance of the compound helicopter was made. Performance optimization was conducted to find the optimum twist, collective, tip speed, and taper using the comprehensive analysis. Blade twist was an important parameter on the aircraft performance and most of the benefit of slowing the rotor occurred at the initial 20 to 30% reduction of rotor tip speed. No stability issues were observed with the current design and the control derivatives did not change much with speed, but did exhibit significant coupling.

NASA helicopter helps fight brush fire at KSC

NASA Technical Reports Server (NTRS)

2000-01-01

A NASA helicopter flies toward the source of the smoke to drop its load of water on a wildfire at KSC. Before being extinguished, the fire burned about 20 acres at a site near gate 2C on Kennedy Parkway North (route 3).

78 FR 65169 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-31

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Deutschland GmbH (Eurocopter) Model EC135 P1, P2, P2+, T1, T2, and T2+ helicopters. This AD requires... GmbH: Amendment 39-17629; Docket No. FAA-2013-0446; Directorate Identifier 2010-SW-007-AD. (a...

NASA helicopter helps fight brush fire at KSC

NASA Technical Reports Server (NTRS)

2000-01-01

A NASA helicopter flies over fire-fighting equipment and personnel in order to drop its load of water on a wildfire at KSC. Before being extinguished, the fire burned about 20 acres at a site near gate 2C on Kennedy Parkway North (route 3).

77 FR 44116 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-27

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Eurocopter Deutschland GmbH (ECD) MBB-BK 117 A-3, MBB-BK 117 A-4, MBB- BK B-1, MBB-BK 117 B-2, and MBB-BK C-1... directive (AD): 2012-14-14 Eurocopter Deutschland GmbH Helicopters: Amendment 39- 17128; Docket No. FAA-2012...

76 FR 76068 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-06

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... GmbH Model BO-105A, BO-105C, BO-105LS A-1, BO- 105LS A-3, and BO-105S helicopters. This proposed AD... airworthy main rotor blade. Note 1: Eurocopter Deutschland GmbH Emergency Alert Service Bulletin No. BO105...

NASA helicopter helps fight brush fire at KSC

NASA Technical Reports Server (NTRS)

2000-01-01

A NASA helicopter dips its fire-fighting bucket into the river to pick up and deliver a cargo of water to a wildfire at KSC. Before being extinguished, the fire burned about 20 acres at a site near gate 2C on Kennedy Parkway North (route 3).

Correlate Life Predictions and Condition Indicators in Helicopter Tail Gearbox Bearings

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.; Bolander, Nathan; Haynes, Chris; Branning, Jeremy; Wade, Daniel R.

2010-01-01

Research to correlate bearing remaining useful life (RUL) predictions with Helicopter Health Usage Monitoring Systems (HUMS) condition indicators (CI) to indicate the damage state of a transmission component has been developed. Condition indicators were monitored and recorded on UH-60M (Black Hawk) tail gearbox output shaft thrust bearings, which had been removed from helicopters and installed in a bearing spall propagation test rig. Condition indicators monitoring the tail gearbox output shaft thrust bearings in UH-60M helicopters were also recorded from an on-board HUMS. The spal-lpropagation data collected in the test rig was used to generate condition indicators for bearing fault detection. A damage progression model was also developed from this data. Determining the RUL of this component in a helicopter requires the CI response to be mapped to the damage state. The data from helicopters and a test rig were analyzed to determine if bearing remaining useful life predictions could be correlated with HUMS condition indicators (CI). Results indicate data fusion analysis techniques can be used to map the CI response to the damage levels.

78 FR 56597 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-13

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Deutschland GmbH (ECD) Model EC135P1, EC135P2, EC135P2+, EC135T1, EC135T2, and EC135T2+ helicopters with... directive (AD): 2013-18-05 Eurocopter Deutschland GmbH: Amendment 39-17578; Docket No. FAA-2013-0398...

78 FR 26715 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-08

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... GmbH (ECD) Model EC135P1, EC135P2, EC135P2+, EC135T1, EC135T2, and EC135T2+ helicopters with certain... airworthiness directive (AD): Eurocopter Deutschland GmbH: Docket No. FAA-2013-0398; Directorate Identifier 2011...

77 FR 20321 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-04

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... Deutschland GmbH (ECD) MBB-BK 117 A-3, MBB-BK 117 A-4, MBB- BK B-1, MBB-BK 117 B-2, and MBB-BK C-1 helicopters... Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 A-4 model. The EASA AD makes no mention of this model. The...

78 FR 30793 - Airworthiness Directives; Eurocopter Deutschland GmbH Model Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-23

... Deutschland GmbH Model Helicopters AGENCY: Federal Aviation Administration (FAA) DOT. ACTION: Notice of... Deutschland GmbH (Eurocopter) Model EC135 P1, P2, P2+, T1, T2, and T2+ helicopters to require inspecting each...): Eurocopter Deutschland GmbH: Docket No. FAA-2013-0446; Directorate Identifier 2010-SW-007-AD. (a...

Optimum Design of a Compound Helicopter

NASA Technical Reports Server (NTRS)

Yeo, Hyeonsoo; Johnson, Wayne

2006-01-01

A design and aeromechanics investigation was conducted for a 100,000-lb compound helicopter with a single main rotor, which is to cruise at 250 knots at 4000 ft/95 deg F condition. Performance, stability, and control analyses were conducted with the comprehensive rotorcraft analysis CAMRAD II. Wind tunnel test measurements of the performance of the H-34 and UH-1D rotors at high advance ratio were compared with calculations to assess the accuracy of the analysis for the design of a high speed helicopter. In general, good correlation was obtained when an increase of drag coefficients in the reverse flow region was implemented. An assessment of various design parameters (disk loading, blade loading, wing loading) on the performance of the compound helicopter was conducted. Lower wing loading (larger wing area) and higher blade loading (smaller blade chord) increased aircraft lift-to-drag ratio. However, disk loading has a small influence on aircraft lift-to-drag ratio. A rotor parametric study showed that most of the benefit of slowing the rotor occurred at the initial 20 to 30% reduction of the advancing blade tip Mach number. No stability issues were observed with the current design. Control derivatives did not change significantly with speed, but the did exhibit significant coupling.

Helicopter approach capability using the differential Global Positioning System

NASA Technical Reports Server (NTRS)

Kaufmann, David N.

1993-01-01

The results of flight tests to determine the feasibility of using the Global Positioning System (GPS) in the differential mode (DGPS) to provide high accuracy, precision navigation and guidance for helicopter approaches to landing are presented. The airborne DGPS receiver and associated equipment is installed in a NASA UH-60 Black Hawk helicopter. The ground-based DGPS reference receiver is located at a surveyed test site and is equipped with a real-time VHF data link to transmit correction information to the airborne DGPS receiver. The corrected airborne DGPS information, together with the preset approach geometry, is used to calculate guidance commands which are sent to the aircraft's approach guidance instruments. The use of DGPS derived guidance for helicopter approaches to landing is evaluated by comparing the DGPS data with the laser tracker truth data. Both standard (3 degrees) and steep (6 degrees and 9 degrees) glidescope straight-in approaches were flown. DGPS positioning accuracy based on a time history analysis of the entire approach was 0.2 m (mean) +/- 1.8 m (2 sigma) laterally and -2.0 m (mean) +/- 3.5 m (2 sigma) vertically for 3 degree glidescope approaches, -0.1 m (mean) +/- 1.5 m (2 sigma) laterally and -1.1 m (mean) +/- 3.5 m (2 sigma) vertically for 6 degree glidescope approaches, and 0.2 m (mean) +/- 1.3 m (2 sigma) laterally and -1.0 m (mean) +/- 2.8 (2 sigma) vertically for 9 degree glidescope approaches. DGPS positioning accuracy at the 200 ft decision height on a standard 3 degree glidescope approach was 0.3 m (mean) +/- 1.5 m (2 sigma) laterally and -2.3 m (mean) +/- 1.6 m (2 sigma) vertically. These errors indicate that the helicopter position based on DGPS guidance satisfies the International Civil Aviation Organization Category 1 lateral and vertical accuracy requirements.

Integration of Diagnostics into Ground Equipment Study. Volume 1

DTIC Science & Technology

2004-07-30

Marine Corps V-22, CH-53E, MH-53E, SH- 60B, MH- 60S /R, AH-1Z and UH -1Y aircraft. In addition, 30 systems are in delivery to the US Army Aviation Applied...simultaneous) can be connected to the VMEP system, which is based on a PC-104 platform and a 233MHz processor. The AH-64 Apache and UH - 60 Blackhawk are outfitted...34A Model-Based Health and Usage Monitoring and Diagnostic System for the UH - 60 Helicopter," Proceedings of the American Helicopter Society 57th

78 FR 44039 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-23

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters with a jettisonable sliding door (door) installed... airworthiness directive (AD): Eurocopter Deutschland GmbH Helicopters (Eurocopter): Docket No. FAA-2013-0642...

78 FR 42409 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-16

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA...) for Eurocopter Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This AD requires... directive (AD): 2013-12-05 Eurocopter Deutschland GmbH Helicopters: Amendment 39- 17483; Docket No. FAA-2013...

78 FR 31394 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-24

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters. This AD... directive (AD): 2013-10-05 Eurocopter Deutschland GmbH Helicopters: Amendment 39- 17458; Docket No. FAA-2013...

Consolidation Needed for Procurements of DoD H-60 Helicopter Spare Parts (REDACTED)

DTIC Science & Technology

2016-10-12

Information Act. Report No. DODIG-2017-002 O C T O B E R 1 2 , 2 0 1 6 Consolidation Needed for Procurements of DoD H -60 Helicopter Spare Parts I N T E G R...Brief Consolidation Needed for Procurements of DoD H -60 Helicopter Spare Parts October 12, 2016 Visit us at www.dodig.mil Objective We determined...whether DoD was effectively managing the procurement of H -60 helicopter ( H -60) spare parts. The Army, Navy, Air Force, and U.S. Special Operations

78 FR 44050 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-23

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... Deutschland GmbH (Eurocopter) Model EC135P2+ and EC135T2+ helicopters. This proposed AD would require... adding the following new airworthiness directive (AD): Eurocopter Deutschland GmbH Helicopters: Docket No...

UH-60A Black Hawk engineering simulation program. Volume 1: Mathematical model

NASA Technical Reports Server (NTRS)

Howlett, J. J.

1981-01-01

A nonlinear mathematical model of the UR-60A Black Hawk helicopter was developed. This mathematical model, which was based on the Sikorsky General Helicopter (Gen Hel) Flight Dynamics Simulation, provides NASA with an engineering simulation for performance and handling qualities evaluations. This mathematical model is total systems definition of the Black Hawk helicopter represented at a uniform level of sophistication considered necessary for handling qualities evaluations. The model is a total force, large angle representation in six rigid body degrees of freedom. Rotor blade flapping, lagging, and hub rotational degrees of freedom are also represented. In addition to the basic helicopter modules, supportive modules were defined for the landing interface, power unit, ground effects, and gust penetration. Information defining the cockpit environment relevant to pilot in the loop simulation is presented.

UH1-Y - Benefits and Deficiencies

DTIC Science & Technology

2009-02-20

Report, NA 01 HCG -1 (hereinafter Test and Evaluation Report). 2 author’s experience. 3 Test and Evaluation Report. 4 Test and Evaluation Report...Critical Intelligence. Aug 14, 24(33). - - - 2008. DOD Approves Full Production for UH-1Y Despite Major Deficiency. Oct 2, 24(40). NA 01-11- HCG -2-1...2008. Operational Test and Evaluation Report, NA 01 HCG -1. Parmalee, Patricia, ed. 2005. Test Time. Aviation Week & Space Technology. Jun 20, 162

77 FR 72913 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-07

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Eurocopter Deutschland GmbH (ECD) Model EC135 helicopters, except the EC 135 P2+ and T2+. This AD requires... apply to all Eurocopter Deutschland GmbH (ECD) model EC135 helicopters, except the EC 135 P2+ and T2...

77 FR 27661 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-11

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... Deutschland GmbH (ECD) model EC135 helicopters, except the EC 135 P2+ and T2+. This proposed AD was prompted...) Applicability This AD applies to all Eurocopter Deutschland GmbH (ECD) Model EC135 helicopters, except EC 135 P2...

Helicopter noise definition report: UH-60A, S-76, A-109, 206-L

DOT National Transportation Integrated Search

1981-12-31

This document presents noise data for the Sikorsky UH-60A Blackhawk, the Sikorsky S-76 Spirit, the Agusta A-109 and the Bell 206-L. The acoustical data are accompanied by phototheodolite tracking data, cockpit instrument panel photo data, and meteoro...

Investigation of Rotor Performance and Loads of a UH-60A Individual Blade Control System

NASA Technical Reports Server (NTRS)

Yeo, Hyeonsoo; Romander, Ethan A.; Norman, Thomas R.

2010-01-01

A full-scale wind tunnel test was recently conducted (March 2009) in the National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-FootWind Tunnel to evaluate the potential of an individual blade control (IBC) system to improve rotor performance and reduce vibrations, loads, and noise for a UH-60A rotor system [1]. This test was the culmination of a long-termcollaborative effort between NASA, U.S. Army, Sikorsky Aircraft Corporation, and ZF Luftfahrttechnik GmbH (ZFL) to demonstrate the benefits of IBC for a UH-60Arotor. Figure 1 shows the UH-60Arotor and IBC system mounted on the NFAC Large Rotor Test Apparatus (LRTA). The IBC concept used in the current study utilizes actuators placed in the rotating frame, one per blade. In particular, the pitch link of the rotor blade was replacedwith an actuator, so that the blade root pitch can be changed independently. This concept, designed for a full-scale UH-60A rotor, was previously tested in the NFAC 80- by 120-FootWind Tunnel in September 2001 at speeds up to 85 knots [2]. For the current test, the same UH-60A rotor and IBC system were tested in the 40- by 80-FootWind Tunnel at speeds up to 170 knots. Figure 2 shows the servo-hydraulic IBC actuator installed between the swashplate and the blade pitch horn. Although previous wind tunnel experiments [3, 4] and analytical studies on IBC [5, 6] have shown the promise to improve the rotor s performance, in-depth correlation studies have not been performed. Thus, the current test provides a unique resource that can be used to assess the accuracy and reliability of prediction methods and refine theoretical models, with the ultimate goal of providing the technology for timely and cost-effective design and development of new rotors. In this paper, rotor performance and loads calculations are carried out using the analyses CAMRAD II and coupled OVERFLOW-2/CAMRAD II and the results are compared with these UH-60A/IBC wind tunnel test data.

Monitoring of pre-frontal oxygen status in helicopter pilots using near-infrared spectrophotometers

PubMed Central

Kikukawa, Azusa; Kobayashi, Asao; Miyamoto, Yoshinori

2008-01-01

Background There are few in-flight studies of cognition-related cerebral oxygen status in helicopter pilots. Methods Four male helicopter pilots volunteered for nine sorties during visual flight in a BK117 and UH-60J. The pilots' pre-frontal oxy-hemoglobin (O2Hb) and deoxy-hemoglobin (HHb) concentration were continuously monitored from the right/left sections of the forehead using near-infrared spectrophotometers with a consideration of motion artifacts. Results The concentration of O2Hb progressively increased (13.98 μmol•L-1 as a maximum increased concentration) in both the right/left sections of the forehead from the basal level during the heightened cognitive demand of helicopter flight. There was comparatively little change (4.32 μmol•L-1 as a maximum increased concentration) in HHb concentration during measurement of helicopter flight. HHb changes were apparently not affected by a heightened cognitive demand of helicopter pilots. Conclusion These results demonstrate that near-infrared spectroscopy, especially O2Hb measurements, provides a sensitive method for the monitoring of cognitive demand (maneuvers) in helicopter pilots. PMID:18616829

Cooperative program for design, fabrication, and testing of graphite/epoxy composite helicopter shafting

NASA Technical Reports Server (NTRS)

Wright, C. C.; Baker, D. J.; Corvelli, N.; Thurston, L.; Clary, R.; Illg, W.

1971-01-01

The fabrication of UH-1 helicopter tail rotor drive shafts from graphite/epoxy composite materials is discussed. Procedures for eliminating wrinkles caused by lack of precure compaction are described. The development of the adhesive bond between aluminum end couplings and the composite tube is analyzed. Performance tests to validate the superiority of the composite materials are reported.

77 FR 49705 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-17

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Deutschland GmbH Model MBB-BK 117 C-2 helicopters. A page reference of the rotorcraft flight manual in the...

78 FR 7312 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-01

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration, DOT. ACTION: Notice of proposed... Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This proposed AD would require changing the... new Airworthiness Directive (AD): Eurocopter Deutschland GmbH: Docket No. FAA-2013-0021; Directorate...

77 FR 37790 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-25

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Eurocopter Deutschland GmbH (ECD) Model EC135 helicopters. The existing EAD, which was previously sent to all... new airworthiness directive (AD): 2012-11-02 Eurocopter Deutschland GmbH: Amendment 39-17065; Docket...

77 FR 42958 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-23

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 (all versions) and BO-105LS... Eurocopter Deutschland GmbH Helicopters: Amendment 39- 17113; Docket No. FAA-2012-0704; Directorate...

Computation of UH-60A Airloads Using CFD/CSD Coupling on Unstructured Meshes

NASA Technical Reports Server (NTRS)

Biedron, Robert T.; Lee-Rausch, Elizabeth M.

2011-01-01

An unsteady Reynolds-averaged Navier-Stokes solver for unstructured grids is used to compute the rotor airloads on the UH-60A helicopter at high-speed and high thrust conditions. The flow solver is coupled to a rotorcraft comprehensive code in order to account for trim and aeroelastic deflections. Simulations are performed both with and without the fuselage, and the effects of grid resolution, temporal resolution and turbulence model are examined. Computed airloads are compared to flight data.

NDARC - NASA Design and Analysis of Rotorcraft Validation and Demonstration

NASA Technical Reports Server (NTRS)

Johnson, Wayne

2010-01-01

Validation and demonstration results from the development of the conceptual design tool NDARC (NASA Design and Analysis of Rotorcraft) are presented. The principal tasks of NDARC are to design a rotorcraft to satisfy specified design conditions and missions, and then analyze the performance of the aircraft for a set of off-design missions and point operating conditions. The aircraft chosen as NDARC development test cases are the UH-60A single main-rotor and tail-rotor helicopter, the CH-47D tandem helicopter, the XH-59A coaxial lift-offset helicopter, and the XV-15 tiltrotor. These aircraft were selected because flight performance data, a weight statement, detailed geometry information, and a correlated comprehensive analysis model are available for each. Validation consists of developing the NDARC models for these aircraft by using geometry and weight information, airframe wind tunnel test data, engine decks, rotor performance tests, and comprehensive analysis results; and then comparing the NDARC results for aircraft and component performance with flight test data. Based on the calibrated models, the capability of the code to size rotorcraft is explored.

Measurement of the UH-60A Hub Large Rotor Test Apparatus Control System Stiffness

NASA Technical Reports Server (NTRS)

Kufeld, Robert M.

2014-01-01

This purpose of this report is to provides details of the measurement of the control system stiffness of the UH-60A rotor hub mounted on the Large Rotor Test Apparatus (UH-60A/LRTA). The UH-60A/LRTA was used in the 40- by 80-Foot Wind Tunnel to complete the full-scale wind tunnel test portion of the NASA / ARMY UH-60A Airloads Program. This report describes the LRTA control system and highlights the differences between the LRTA and UH-60A aircraft. The test hardware, test setup, and test procedures are also described. Sample results are shown, including the azimuthal variation of the measured control system stiffness for three different loadings and two different dynamic actuator settings. Finally, the azimuthal stiffness is converted to fixed system values using multi-blade transformations for input to comprehensive rotorcraft prediction codes.

78 FR 25361 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-01

... Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT... Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This AD requires inspecting the long tail... directive (AD): 2013-03-18 Eurocopter Deutschland GmbH (Eurocopter): Amendment 39- 17352; Docket No. FAA...

77 FR 27659 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-11

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... Deutschland GmbH (ECD) Model BO-105A, BO-105C, and BO-105S helicopters. This proposed AD is prompted by...

77 FR 69558 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-20

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Eurocopter Deutschland GmbH (ECD) Model EC135 P1, EC135 P2, EC135 P2+, EC135 T1... with this AD through an AMOC. (h) Additional Information (1) Eurocopter Emergency Alert Service...

Rotorcraft Downwash Flow Field Study to Understand the Aerodynamics of Helicopter Brownout

NASA Technical Reports Server (NTRS)

Wadcock, Alan J.; Ewing, Lindsay A.; Solis, Eduardo; Potsdam, Mark; Rajagopalan, Ganesh

2008-01-01

Rotorcraft brownout is caused by the entrainment of dust and sand particles in helicopter downwash, resulting in reduced pilot visibility during low, slow flight and landing. Recently, brownout has become a high-priority problem for military operations because of the risk to both pilot and equipment. Mitigation of this problem has focused on flight controls and landing maneuvers, but current knowledge and experimental data describing the aerodynamic contribution to brownout are limited. This paper focuses on downwash characteristics of a UH-60 Blackhawk as they pertain to particle entrainment and brownout. Results of a full-scale tuft test are presented and used to validate a high-fidelity Navier-Stokes computational fluid dynamics (CFD) calculation. CFD analysis for an EH-101 Merlin helicopter is also presented, and its flow field characteristics are compared with those of the UH-60.

Comparison of Test Stand and Helicopter Oil Cooler Bearing Condition Indicators

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.; Branning, Jeremy; Wade, Damiel R.; Bolander, Nathan

2010-01-01

The focus of this paper was to compare the performance of HUMS condition indicators (CI) when detecting a bearing fault in a test stand or on a helicopter. This study compared data from two sources: first, CI data collected from accelerometers installed on two UH-60 Black Hawk helicopters when oil cooler bearing faults occurred, along with data from helicopters with no bearing faults; and second, CI data that was collected from ten cooler bearings, healthy and faulted, that were removed from fielded helicopters and installed in a test stand. A method using Receiver Operating Characteristic (ROC) curves to compare CI performance was demonstrated. Results indicated the bearing energy CI responded differently for the helicopter and the test stand. Future research is required if test stand data is to be used validate condition indicator performance on a helicopter.

78 FR 4090 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-18

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This proposed AD would require determining if a... amends Sec. 39.13 by adding the following new airworthiness directive (AD): Eurocopter Deutschland GmbH...

77 FR 37777 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-25

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... directive (AD) for all Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters. That AD currently... Safety Agency AD No. 2011-0162, dated August 30, 2011. (h) Subject Joint Aircraft Service Component (JASC...

Signal Detection Theory Applied to Helicopter Transmission Diagnostic Thresholds

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.; Keller, Jonathan A.; Wade, Daniel R.

2008-01-01

Helicopter Health Usage Monitoring Systems (HUMS) have potential for providing data to support increasing the service life of a dynamic mechanical component in the transmission of a helicopter. Data collected can demonstrate the HUMS condition indicator responds to a specific component fault with appropriate alert limits and minimal false alarms. Defining thresholds for specific faults requires a tradeoff between the sensitivity of the condition indicator (CI) limit to indicate damage and the number of false alarms. A method using Receiver Operating Characteristic (ROC) curves to assess CI performance was demonstrated using CI data collected from accelerometers installed on several UH60 Black Hawk and AH64 Apache helicopters and an AH64 helicopter component test stand. Results of the analysis indicate ROC curves can be used to reliably assess the performance of commercial HUMS condition indicators to detect damaged gears and bearings in a helicopter transmission.

Signal Detection Theory Applied to Helicopter Transmission Diagnostic Thresholds

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.; Keller, Jonathan A.; Wade, Daniel R.

2009-01-01

Helicopter Health Usage Monitoring Systems (HUMS) have potential for providing data to support increasing the service life of a dynamic mechanical component in the transmission of a helicopter. Data collected can demonstrate the HUMS condition indicator responds to a specific component fault with appropriate alert limits and minimal false alarms. Defining thresholds for specific faults requires a tradeoff between the sensitivity of the condition indicator (CI) limit to indicate damage and the number of false alarms. A method using Receiver Operating Characteristic (ROC) curves to assess CI performance was demonstrated using CI data collected from accelerometers installed on several UH60 Black Hawk and AH64 Apache helicopters and an AH64 helicopter component test stand. Results of the analysis indicate ROC curves can be used to reliably assess the performance of commercial HUMS condition indicators to detect damaged gears and bearings in a helicopter transmission.

Performance Data from a Wind-Tunnel Test of Two Main-rotor Blade Designs for a Utility-Class Helicopter

NASA Technical Reports Server (NTRS)

Singleton, Jeffrey D.; Yeager, William T., Jr.; Wilbur, Matthew L.

1990-01-01

An investigation was conducted in the NASA Langley Transonic Dynamics Tunnel to evaluate an advanced main rotor designed for use on a utility class helicopter, specifically the U.S. Army UH-60A Blackhawk. This rotor design incorporated advanced twist, airfoil cross sections, and geometric planform. For evaluation purposes, the current UH-60A main rotor was also tested and is referred to as the baseline blade set. A total of four blade sets were tested. One set of both the baseline and the advanced rotors were dynamically scaled to represent a full scale helicopter rotor blade design. The remaining advanced and baseline blade sets were not dynamically scaled so as to isolate the effects of structural elasticity. The investigation was conducted in hover and at rotor advance ratios ranging from 0.15 to 0.4 at a range of nominal test medium densities from 0.00238 to 0.009 slugs/cu ft. This range of densities, coupled with varying rotor lift and propulsive force, allowed for the simulation of several vehicle gross weight and density altitude combinations. Performance data are presented for all blade sets without analysis; however, cross referencing of data with flight condition may be useful to the analyst for validating aeroelastic theories and design methodologies as well as for evaluating advanced design parameters.

77 FR 43736 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-26

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration, DOT. ACTION: Notice of proposed... Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This proposed AD is prompted by the discovery... Deutschland GmbH: Docket No. FAA-2012-0773; Directorate Identifier 2009-SW-71-AD. (a) Applicability This AD...

78 FR 40047 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-03

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... GmbH (ECD) Model EC135 and MBB-BK 117 C-2 helicopters. This proposed AD is prompted by the discovery... amends Sec. 39.13 by adding the following new airworthiness directive (AD): Eurocopter Deutschland GmbH...

78 FR 2223 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-10

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... GmbH (Eurocopter) Model BO-105A, BO-105C, BO- 105S, BO-105LS A-1, BO-105LS A-3, EC135 P1, EC135 P2... new airworthiness directive (AD): Eurocopter Deutschland GmbH: Docket No. FAA-2012-1305; Directorate...

78 FR 37446 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-21

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Deutschland GmbH (Eurocopter) Model BO-105A, BO-105C, BO- 105S, BO-105LS A-1, BO-105LS A-3, EC135 P1, EC135 P2... new airworthiness directive (AD): 2013-11-15 Eurocopter Deutschland GmbH: Amendment 39-17475; Docket...

Helicopter approach capability using the differential global positioning system. M.S. Thesis

NASA Technical Reports Server (NTRS)

Kaufmann, David N.

1993-01-01

The results of flight tests to determine the feasibility of using the Global Positioning System (GPS) in the differential mode (DGPS) to provide high accuracy, precision navigation, and guidance for helicopter approaches to landing are presented. The airborne DGPS receiver and associated equipment is installed in a NASA UH-60 Black Hawk helicopter. The ground-based DGPS reference receiver is located at a surveyed test site and is equipped with a real-time VHF data link to transmit correction information to the airborne DGPS receiver. The corrected airborne DGPS information, together with the preset approach geometry, is used to calculate guidance commands which are sent to the aircraft's approach guidance instruments. The use of DGPS derived guidance for helicopter approaches to landing is evaluated by comparing the DGPS data with the laser tracker truth data. Both standard (3 deg) and steep (6 deg and 9 deg) glideslope straight-in approaches were flown. DGPS positioning accuracy based on a time history analysis of the entire approach was 0.2 m (mean) +/- 1.8 m (2 sigma) laterally and -2.0 m (mean) +/- 3.5 m (2 sigma) vertically for 3 deg glideslope approaches, -0.1 m (mean) +/- 1.5 m (2 sigma) laterally and -1.1 m (mean) +/- 3.5 m (2 sigma) vertically for 6 deg glideslope approaches and 0.2 m (mean) +/- 1.3 m (2 sigma) laterally and -1.0 m (mean) +/- 2.8 m (2 sigma) vertically for 9 deg glideslope approaches. DGPS positioning accuracy at the 200 ft decision height (DH) on a standard 3 deg slideslope approach was 0.3 m (mean) +/- 1.5 m (2 sigma) laterally and -2.3 m (mean) +/- 1.6 m (2 sigma) vertically. These errors indicate that the helicopter position based on DGPS guidance satisfies the International Civil Aviation Organization (ICAO) Category 1 (CAT 1) lateral and vertical navigational accuracy requirements.

Rotorcraft handling-qualities design criteria development

NASA Technical Reports Server (NTRS)

Aiken, Edwin W.; Lebacqz, J. Victor; Chen, Robert T. N.; Key, David L.

1988-01-01

Joint NASA/Army efforts at the Ames Research Center to develop rotorcraft handling-qualities design criteria began in earnest in 1975. Notable results were the UH-1H VSTOLAND variable stability helicopter, the VFA-2 camera-and-terrain-board simulator visual system, and the generic helicopter real-time mathematical model, ARMCOP. An initial series of handling-qualities studies was conducted to assess the effects of rotor design parameters, interaxis coupling, and various levels of stability and control augmentation. The ability to conduct in-flight handling-qualities research was enhanced by the development of the NASA/Army CH-47 variable-stability helicopter. Research programs conducted using this vehicle include vertical-response investigations, hover augmentation systems, and the effects of control-force characteristics. The handling-qualities data base was judged to be sufficient to allow an update of the military helicopter handling-qualities specification, MIL-H-8501. These efforts, including not only the in-house experimental work but also contracted research and collaborative programs performed under the auspices of various international agreements. The report concludes by reviewing the topics that are currently most in need of work, and the plans for addressing these topics.

Analytical methodology for determination of helicopter IFR precision approach requirements. [pilot workload and acceptance level

NASA Technical Reports Server (NTRS)

Phatak, A. V.

1980-01-01

A systematic analytical approach to the determination of helicopter IFR precision approach requirements is formulated. The approach is based upon the hypothesis that pilot acceptance level or opinion rating of a given system is inversely related to the degree of pilot involvement in the control task. A nonlinear simulation of the helicopter approach to landing task incorporating appropriate models for UH-1H aircraft, the environmental disturbances and the human pilot was developed as a tool for evaluating the pilot acceptance hypothesis. The simulated pilot model is generic in nature and includes analytical representation of the human information acquisition, processing, and control strategies. Simulation analyses in the flight director mode indicate that the pilot model used is reasonable. Results of the simulation are used to identify candidate pilot workload metrics and to test the well known performance-work-load relationship. A pilot acceptance analytical methodology is formulated as a basis for further investigation, development and validation.

Helicopter Reliability and Maintainability Trends during Development and Production.

DTIC Science & Technology

1981-07-01

engine entry (the T-53) showed improvement in successive models. For helicopters, we have mixed results: some improved (YUH-60A, CH-47, UH-lD, AH-IG...understand the linkage between R&M program goals and life cycle costs, however, it is necessary to understand-- (1) what resource levels are required during...attributes of the system; (3) how those field attributes affect the cost of owner- ship of the system; and (4) whether or not, and at what cost, R&M values

An Analysis of Factors That Influence Logistics, Operational Availability, and Flight Hour Supply of the German Attack Helicopter Fleet

DTIC Science & Technology

2017-06-01

maintenance times from the fleet are randomly resampled when running the model to enhance model realism. The use of a simulation model to represent the...helicopter regiment. 2. Attack Helicopter UH TIGER The EC665, or Airbus Helicopter TIGER, (Figure 3) is a four- bladed , twin- engine multi-role attack...migrated into the automated management system SAP Standard Product Family (SASPF), and the usage clock starts to run with the amount of the current

78 FR 52410 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA... Deutschland GmbH (ECD) Model BO-105A, BO-105C, BO-105S, BO- 105LS A-1, BO-105LS A-3, MBB-BK 117 A-1, MBB-BK... directive (AD): 2013-16-13 Eurocopter Deutschland GmbH (ECD): Amendment 39-17551; Docket No. FAA-2012-0887...

The Danger Zone for Noise Hazards Around the Black Hawk Helicopter.

PubMed

Jones, Heath G; Greene, Nathaniel T; Chen, Michael R; Azcona, Cierrah M; Archer, Brandon J; Reeves, Efrem R

2018-06-01

During ground operations, rotary-wing aircraft engines and subsystems produce noise hazards that place airfield personnel at risk for hearing damage. The noise exposure levels outside the aircraft during various operating conditions, and the distances from aircraft at which they drop to safe levels, are not readily available. The current study measured noise levels at various positions around the UH-60 Black Hawk helicopter for three operating conditions typically used when the aircraft is on the ground. Microphones were positioned systematically around the helicopter and A-weighted sound pressure levels (SPLs) were computed from the recordings. In addition, the 85-dBA SPL contour around the aircraft was mapped. The resulting A-weighted SPLs and contour mapping were used to determine the noise hazard area around the helicopter. Measurements reported here show noise levels of 105 dB or greater in all operating conditions. The fueling location at the left rear of the aircraft near the auxiliary power unit (APU) is the area of greatest risk for noise-induced hearing loss (NIHL). Additionally, sound field contours indicate noise hazard areas (>85 dBA SPL) can extend beyond 100 ft from the helicopter. This report details the areas of greatest risk for auditory injury around the UH-60 Black Hawk helicopter. Our findings suggest the area of hazardous noise levels around the aircraft can extend to neighboring aircraft, particularly on the side of the aircraft where the APU is located. Hearing protection should be worn whenever the aircraft is operating, even if working at a distance.Jones HG, Greene NT, Chen MR, Azcona CM, Archer BJ, Reeves ER. The danger zone for noise hazards around the Black Hawk helicopter. Aerosp Med Hum Perform. 2018; 89(6):547-551.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: McDonnell-Douglas Helicopter Company achievements

NASA Technical Reports Server (NTRS)

Toossi, Mostafa; Weisenburger, Richard; Hashemi-Kia, Mostafa

1993-01-01

This paper presents a summary of some of the work performed by McDonnell Douglas Helicopter Company under NASA Langley-sponsored rotorcraft structural dynamics program known as DAMVIBS (Design Analysis Methods for VIBrationS). A set of guidelines which is applicable to dynamic modeling, analysis, testing, and correlation of both helicopter airframes and a large variety of structural finite element models is presented. Utilization of these guidelines and the key features of their applications to vibration modeling of helicopter airframes are discussed. Correlation studies with the test data, together with the development and applications of a set of efficient finite element model checkout procedures, are demonstrated on a large helicopter airframe finite element model. Finally, the lessons learned and the benefits resulting from this program are summarized.

Analysis of a Hovering Rotor in Icing Conditions

NASA Technical Reports Server (NTRS)

Narducci, Robert; Kreeger, Richard E.

2012-01-01

A high fidelity analysis method is proposed to evaluate the ice accumulation and the ensuing rotor performance degradation for a helicopter flying through an icing cloud. The process uses computational fluid dynamics (CFD) coupled to a rotorcraft comprehensive code to establish the aerodynamic environment of a trimmed rotor prior to icing. Based on local aerodynamic conditions along the rotor span and accounting for the azimuthal variation, an ice accumulation analysis using NASA's Lewice3D code is made to establish the ice geometry. Degraded rotor performance is quantified by repeating the high fidelity rotor analysis with updates which account for ice shape and mass. The process is applied on a full-scale UH-1H helicopter in hover using data recorded during the Helicopter Icing Flight Test Program.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program : Bell Helicopter Textron accomplishments

NASA Technical Reports Server (NTRS)

Cronkhite, James D.

1993-01-01

Accurate vibration prediction for helicopter airframes is needed to 'fly from the drawing board' without costly development testing to solve vibration problems. The principal analytical tool for vibration prediction within the U.S. helicopter industry is the NASTRAN finite element analysis. Under the NASA DAMVIBS research program, Bell conducted NASTRAN modeling, ground vibration testing, and correlations of both metallic (AH-1G) and composite (ACAP) airframes. The objectives of the program were to assess NASTRAN airframe vibration correlations, to investigate contributors to poor agreement, and to improve modeling techniques. In the past, there has been low confidence in higher frequency vibration prediction for helicopters that have multibladed rotors (three or more blades) with predominant excitation frequencies typically above 15 Hz. Bell's findings under the DAMVIBS program, discussed in this paper, included the following: (1) accuracy of finite element models (FEM) for composite and metallic airframes generally were found to be comparable; (2) more detail is needed in the FEM to improve higher frequency prediction; (3) secondary structure not normally included in the FEM can provide significant stiffening; (4) damping can significantly affect phase response at higher frequencies; and (5) future work is needed in the areas of determination of rotor-induced vibratory loads and optimization.

Automated Power Assessment for Helicopter Turboshaft Engines

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Litt, Jonathan S.

2008-01-01

An accurate indication of available power is required for helicopter mission planning purposes. Available power is currently estimated on U.S. Army Blackhawk helicopters by performing a Maximum Power Check (MPC), a manual procedure performed by maintenance pilots on a periodic basis. The MPC establishes Engine Torque Factor (ETF), an indication of available power. It is desirable to replace the current manual MPC procedure with an automated approach that will enable continuous real-time assessment of available power utilizing normal mission data. This report presents an automated power assessment approach which processes data currently collected within helicopter Health and Usage Monitoring System (HUMS) units. The overall approach consists of: 1) a steady-state data filter which identifies and extracts steady-state operating points within HUMS data sets; 2) engine performance curve trend monitoring and updating; and 3) automated ETF calculation. The algorithm is coded in MATLAB (The MathWorks, Inc.) and currently runs on a PC. Results from the application of this technique to HUMS mission data collected from UH-60L aircraft equipped with T700-GE-701C engines are presented and compared to manually calculated ETF values. Potential future enhancements are discussed.

Piloted Evaluation of Modernized Limited Authority Control Laws in the NASA-Ames Vertical Motion Simulator (VMS)

NASA Technical Reports Server (NTRS)

Sahasrabudhe, Vineet; Melkers, Edgar; Faynberg, Alexander; Blanken, Chris L.

2003-01-01

The UH-60 BLACK HAWK was designed in the 1970s, when the US Army primarily operated during the day in good visual conditions. Subsequently, the introduction of night-vision goggles increased the BLACK HAWK'S mission effectiveness, but the accident rate also increased. The increased accident rate is strongly tied to increased pilot workload as a result of a degradation in visual cues. Over twenty years of research in helicopter flight control and handling qualities has shown that these degraded handling qualities can be recovered by modifying the response type of the helicopter in low speed flight. Sikorsky Aircraft Corporation initiated a project under the National Rotorcraft Technology Center (NRTC) to develop modern flight control laws while utilizing the existing partial authority Stability Augmentation System (SAS) of the BLACK HAWK. This effort resulted in a set of Modernized Control Laws (MCLAWS) that incorporate rate command and attitude command response types. Sikorsky and the US Army Aeroflightdynamics Directorate (AFDD) conducted a piloted simulation on the NASA-Ames Vertical h4otion Simulator, to assess potential handling qualities and to reduce the risk of subsequent implementation and flight test of these modern control laws on AFDD's EH-60L helicopter. The simulation showed that Attitude Command Attitude Hold control laws in pitch and roll improve handling qualities in the low speed flight regime. These improvements are consistent across a range of mission task elements and for both good and degraded visual environments. The MCLAWS perform better than the baseline UH-60A control laws in the presence of wind and turbulence. Finally, while the improved handling qualities in the pitch and roll axis allow the pilot to pay more attention to the vertical axis and hence altitude performance also improves, it is clear from pilot comments and altitude excursions that the addition of an Altitude Hold function would further reduce workload and improve overall

Heli/SITAN: A Terrain Referenced Navigation algorithm for helicopters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hollowell, J.

1990-01-01

Heli/SITAN is a Terrain Referenced Navigation (TRN) algorithm that utilizes radar altimeter ground clearance measurements in combination with a conventional navigation system and a stored digital terrain elevation map to accurately estimate a helicopter's position. Multiple Model Adaptive Estimation (MMAE) techniques are employed using a bank of single state Kalman filters to ensure that reliable position estimates are obtained even in the face of large initial position errors. A real-time implementation of the algorithm was tested aboard a US Army UH-1 helicopter equipped with a Singer-Kearfott Doppler Velocity Sensor (DVS) and a Litton LR-80 strapdown Attitude and Heading Reference Systemmore » (AHRS). The median radial error of the position fixes provided in real-time by this implementation was less than 50 m for a variety of mission profiles. 6 refs., 7 figs.« less

Extending access to specialist services: the impact of an onsite helipad and analysis of the first 100 flights.

PubMed

Freshwater, Eleanor S; Dickinson, Phillip; Crouch, Robert; Deakin, Charles D; Eynon, C Andy

2014-02-01

In November 2011, University Hospital Southampton (UHS), now a major trauma centre, opened its onsite helipad, allowing patients to be brought to the emergency department (ED) directly by air ambulance. Prior to this, helicopters were required to land at a local playing field and the patient had to be transferred by land ambulance. This study aims to investigate the impact this change in practice has had on the flow of patients to the ED. The authors completed a retrospective case analysis of the first 100 patients brought directly to UHS by helicopter. Data were obtained from ED notes and helicopter provider databases. Analysis was conducted on the type of incident and appropriateness of referral. Incident locations were plotted geographically. 100 patients arrived at UHS ED by helicopter between 17 November 2011 and 31 March 2012. Of these, 79 were primary helicopter emergency medical service (HEMS) missions and 21 were secondary transfers from other hospitals. Of the HEMS patients, 38 were likely to have been transported to another hospital, had there not been an onsite helipad at UHS. 29 passed another suitable receiving hospital en route and therefore may have come to UHS for speciality services. The provision of an onsite, 24 h helipad facility at UHS has resulted in a significant number of patients being transported to the hospital by helicopter who might otherwise have attended an alternative hospital.

Using Dynamic Interface Modeling and Simulation to Develop a Launch and Recovery Flight Simulation for a UH-60A Blackhawk

NASA Technical Reports Server (NTRS)

Sweeney, Christopher; Bunnell, John; Chung, William; Giovannetti, Dean; Mikula, Julie; Nicholson, Bob; Roscoe, Mike

2001-01-01

Joint Shipboard Helicopter Integration Process (JSHIP) is a Joint Test and Evaluation (JT&E) program sponsored by the Office of the Secretary of Defense (OSD). Under the JSHDP program is a simulation effort referred to as the Dynamic Interface Modeling and Simulation System (DIMSS). The purpose of DIMSS is to develop and test the processes and mechanisms that facilitate ship-helicopter interface testing via man-in-the-loop ground-based flight simulators. Specifically, the DIMSS charter is to develop an accredited process for using a flight simulator to determine the wind-over-the-deck (WOD) launch and recovery flight envelope for the UH-60A ship/helicopter combination. DIMSS is a collaborative effort between the NASA Ames Research Center and OSD. OSD determines the T&E and warfighter training requirements, provides the programmatics and dynamic interface T&E experience, and conducts ship/aircraft interface tests for validating the simulation. NASA provides the research and development element, simulation facility, and simulation technical experience. This paper will highlight the benefits of the NASA/JSHIP collaboration and detail achievements of the project in terms of modeling and simulation. The Vertical Motion Simulator (VMS) at NASA Ames Research Center offers the capability to simulate a wide range of simulation cueing configurations, which include visual, aural, and body-force cueing devices. The system flexibility enables switching configurations io allow back-to-back evaluation and comparison of different levels of cueing fidelity in determining minimum training requirements. The investigation required development and integration of several major simulation system at the VMS. A new UH-60A BlackHawk interchangeable cab that provides an out-the-window (OTW) field-of-view (FOV) of 220 degrees in azimuth and 70 degrees in elevation was built. Modeling efforts involved integrating Computational Fluid Dynamics (CFD) generated data of an LHA ship airwake and

Neural Network Modeling of UH-60A Pilot Vibration

NASA Technical Reports Server (NTRS)

Kottapalli, Sesi

2003-01-01

Full-scale flight-test pilot floor vibration is modeled using neural networks and full-scale wind tunnel test data for low speed level flight conditions. Neural network connections between the wind tunnel test data and the tlxee flight test pilot vibration components (vertical, lateral, and longitudinal) are studied. Two full-scale UH-60A Black Hawk databases are used. The first database is the NASMArmy UH-60A Airloads Program flight test database. The second database is the UH-60A rotor-only wind tunnel database that was acquired in the NASA Ames SO- by 120- Foot Wind Tunnel with the Large Rotor Test Apparatus (LRTA). Using neural networks, the flight-test pilot vibration is modeled using the wind tunnel rotating system hub accelerations, and separately, using the hub loads. The results show that the wind tunnel rotating system hub accelerations and the operating parameters can represent the flight test pilot vibration. The six components of the wind tunnel N/rev balance-system hub loads and the operating parameters can also represent the flight test pilot vibration. The present neural network connections can significandy increase the value of wind tunnel testing.

GT-5 Recovery Being Hoisted to Helicopter

NASA Image and Video Library

1965-08-29

S65-46646 (29 Aug. 1965) --- Astronaut L. Gordon Cooper Jr. is hoisted up to a Navy helicopter during recovery operations in the Atlantic Ocean of the Gemini-5 spacecraft. The NASA Headquarter alternative photo number is 65-H-688.

ARC-1993-AC93-0010-17

NASA Image and Video Library

1993-01-11

Sikorsky UH-60 (USA 82-23748 NASA-748) Airloads research aircraft - Blackhawk helicopter with MUX-Bucket in flight over Livermore, CA. Note: Used in publication in Flight Research at Ames; 57 Years of Development and Validation of Aeronautical Technology NASA SP-1998-3300 fig. 135

Life Forecasting as a Logistics Technique.

DTIC Science & Technology

1982-01-01

Two examples of RCM applications were investigated directly by the MIT project team: the T53-L-13B engine for the UH -lH Helicopter and the M- 60 Tank...for RCM activities. The candidate systems and the respective 4 readiness commands were the UH -lH helicopter (TSARCOM), TOY Weapon System (MIRCOM), M...have capability for developing Failure Modes and Effects Analyses ( FMEA ). 5. Accurate and dependable field or test data are generally not available. 6

UNBROKEN: UH 1N AIRCREW CONTINUE OPS DESPITE WEAK HEARING PROTECTION

DTIC Science & Technology

2016-02-29

AU/ACSC/2016 AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY UNBROKEN: UH-1N AIRCREW CONTINUE OPS DESPITE WEAK HEARING... student training. The final one at Fairchild AFB, Washington, is focused on search and rescue operations and supports the Survival, Evasion

Comparison of Computed and Measured Vortex Evolution for a UH-60A Rotor in Forward Flight

NASA Technical Reports Server (NTRS)

Ahmad, Jasim Uddin; Yamauchi, Gloria K.; Kao, David L.

2013-01-01

A Computational Fluid Dynamics (CFD) simulation using the Navier-Stokes equations was performed to determine the evolutionary and dynamical characteristics of the vortex flowfield for a highly flexible aeroelastic UH-60A rotor in forward flight. The experimental wake data were acquired using Particle Image Velocimetry (PIV) during a test of the fullscale UH-60A rotor in the National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind Tunnel. The PIV measurements were made in a stationary cross-flow plane at 90 deg rotor azimuth. The CFD simulation was performed using the OVERFLOW CFD solver loosely coupled with the rotorcraft comprehensive code CAMRAD II. Characteristics of vortices captured in the PIV plane from different blades are compared with CFD calculations. The blade airloads were calculated using two different turbulence models. A limited spatial, temporal, and CFD/comprehensive-code coupling sensitivity analysis was performed in order to verify the unsteady helicopter simulations with a moving rotor grid system.

The isotype repertoire of antibodies against novel UH-RA peptides in rheumatoid arthritis.

PubMed

De Winter, Liesbeth M; Geusens, Piet; Lenaerts, Jan; Vanhoof, Johan; Stinissen, Piet; Somers, Veerle

2016-06-07

Recently, autoantibodies against novel UH-RA peptides (UH-RA.1 and UH-RA.21) were identified as candidate biomarkers for patients with rheumatoid arthritis (RA) who are seronegative for the current diagnostic markers rheumatoid factor and anticitrullinated protein antibodies. Previously, screening for anti-UH-RA autoantibodies was based on measuring the immunoglobulin (Ig) G response. We aimed to investigate whether measurement of other isotypes could improve the performance of diagnostic testing. In addition, assigning the isotype profile might provide valuable information on effector functions of the antibodies. The isotype profile of antibodies against UH-RA.1 and UH-RA.21 was studied. The IgG, IgM, and IgA classes, together with the 4 different IgG subclasses, were determined in 285 patients with RA, 88 rheumatic control subjects, and 90 healthy control subjects. Anti-UH-RA.1 antibodies were primarily of the IgM isotype and twice as prevalent as IgG (IgG3-dominated) and IgA. RA sensitivity when testing for anti-UH-RA.1 IgM was shown to be higher than when testing for the IgG isotype: 18 % versus 9 % sensitivity when RA specificity was set to 90 %. Within antibodies against UH-RA.21, IgG and IgA were more common than IgM. Different anti-UH-RA.21 IgG subclasses were found, with the highest prevalence found for IgG2. Combined testing for IgG and IgA slightly increased RA sensitivity of UH-RA.21-specific antibody testing to 27 % compared with solely testing for IgG (23 %). Notably, a higher number of anti-UH-RA.21 antibody isotypes was related to increased levels of erythrocyte sedimentation rate. Finally, for both antibody responses, the full antibody isotype use was demonstrated in early and seronegative disease. The isotype distribution of anti-UH-RA.1 and anti-UH-RA.21 antibodies was successfully outlined, and, for antibodies against UH-RA.1, we found that isotype-specific testing might have implications for diagnostic testing. The exact mechanisms by

Implementation of a Helicopter Flight Simulator with Individual Blade Control

NASA Astrophysics Data System (ADS)

Zinchiak, Andrew G.

2011-12-01

Nearly all modern helicopters are designed with a swashplate-based system for control of the main rotor blades. However, the swashplate-based approach does not provide the level of redundancy necessary to cope with abnormal actuator conditions. For example, if an actuator fails (becomes locked) on the main rotor, the cyclic inputs are consequently fixed and the helicopter may become stuck in a flight maneuver. This can obviously be seen as a catastrophic failure, and would likely lead to a crash. These types of failures can be overcome with the application of individual blade control (IBC). IBC is achieved using the blade pitch control method, which provides complete authority of the aerodynamic characteristics of each rotor blade at any given time by replacing the normally rigid pitch links between the swashplate and the pitch horn of the blade with hydraulic or electronic actuators. Thus, IBC can provide the redundancy necessary for subsystem failure accommodation. In this research effort, a simulation environment is developed to investigate the potential of the IBC main rotor configuration for fault-tolerant control. To examine the applications of IBC to failure scenarios and fault-tolerant controls, a conventional, swashplate-based linear model is first developed for hover and forward flight scenarios based on the UH-60 Black Hawk helicopter. The linear modeling techniques for the swashplate-based helicopter are then adapted and expanded to include IBC. Using these modified techniques, an IBC based mathematical model of the UH-60 helicopter is developed for the purposes of simulation and analysis. The methodology can be used to model and implement a different aircraft if geometric, gravimetric, and general aerodynamic data are available. Without the kinetic restrictions of the swashplate, the IBC model effectively decouples the cyclic control inputs between different blades. Simulations of the IBC model prove that the primary control functions can be manually

Using Fly-By-Wire Technology in Future Models of the UH-60 and Other Rotary Wing Aircraft

NASA Technical Reports Server (NTRS)

Solem, Courtney K.

2011-01-01

Several fixed-winged airplanes have successfully used fly-by-wire (FBW) technology for the last 40 years. This technology is now beginning to be incorporated into rotary wing aircraft. By using FBW technology, manufacturers are expecting to improve upon the weight, maintenance time and costs, handling and reliability of the aircraft. Before mass production of this new system begins in new models such as the UH-60MU, testing must be conducted to insure the safety of this technology as well as to reassure others it will be worth the time and money to make such a dramatic change to a perfectly functional machine. The RASCAL JUH-60A has been modified for these purposes. This Black Hawk helicopter has already been equipped with the FBW technology and can be configured as a near perfect representation of the UH-60MU. Because both machines have very similar qualities, the data collected from the RASCAL can be used to make future decisions about the UH-60MU. The U.S. Army AFDD Flight Project Office oversees all the design modifications for every hardware system used in the RASCAL aircraft. This project deals with specific designs and analyses of unique RASCAL aircraft subsystems and their modifications to conduct flight mechanics research.

78 FR 49115 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-13

... Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA...) that was published in the Federal Register. The AD applies to certain Eurocopter Deutschland GmbH...

NASA rotor system research aircraft flight-test data report: Helicopter and compound configuration

NASA Technical Reports Server (NTRS)

Erickson, R. E.; Kufeld, R. M.; Cross, J. L.; Hodge, R. W.; Ericson, W. F.; Carter, R. D. G.

1984-01-01

The flight test activities of the Rotor System Research Aircraft (RSRA), NASA 740, from June 30, 1981 to August 5, 1982 are reported. Tests were conducted in both the helicopter and compound configurations. Compound tests reconfirmed the Sikorsky flight envelope except that main rotor blade bending loads reached endurance at a speed about 10 knots lower than previously. Wing incidence changes were made from 0 to 10 deg.

Evaluation of Installation of Lightweight Doppler Navigation System (LDNS) in Iroquois UH-1H Aircraft.

DTIC Science & Technology

1983-11-01

1.1 Background 6 1.2 Purpose 6 2. Description of Equipment Under Test 7 2.1 Description of LDNS K51OA-009-O1 7 2.2 Description of SHIU K350A-013-02 11...Goggles (NVG). These evaluations will now be reported under separate tasks; however, the use of NVGs, in conjunction with the LDNS, is briefly discussed in...utility helicopter transport and gunship missions. -7- 2. DESCRIPTION OF EQUIPMENT UNDER TEST 2.1 Description of LDNS K51OA-O09-O 2.1.1 The K5IOA-O09

An evaluation of helicopter noise and vibration ride qualities criteria

NASA Technical Reports Server (NTRS)

Hammond, C. E.; Hollenbaugh, D. D.; Clevenson, S. A.; Leatherwood, J. D.

1981-01-01

Two methods of quantifying helicopter ride quality; absorbed power for vibration only and the NASA ride comfort model for both noise and vibration are discussed. Noise and vibration measurements were obtained on five operational US Army helicopters. The data were converted to both absorbed power and DISC's (discomfort units used in the NASA model) for specific helicopter flight conditions. Both models indicate considerable variation in ride quality between the five helicopters and between flight conditions within each helicopter.

A mathematical simulation model of the CH-47B helicopter, volume 1

NASA Technical Reports Server (NTRS)

Weber, J. M.; Liu, T. Y.; Chung, W.

1984-01-01

A nonlinear simulation model of the CH-47B helicopter was adapted for use in the NASA Ames Research Center (ARC) simulation facility. The model represents the specific configuration of the ARC variable stability CH-47B helicopter and will be used in ground simulation research and to expedite and verify flight experiment design. Modeling of the helicopter uses a total force approach in six rigid body degrees of freedom. Rotor dynamics are simulated using the Wheatlely-Bailey equations including steady-state flapping dynamics. Also included in the model is the option for simulation of external suspension, slung-load equations of motion.

A model structure for identification of linear models of the UH-60 helicopter in hover and forward flight

DOT National Transportation Integrated Search

1995-08-01

A linear model structure applicable to identification of the UH-60 flight : dynamics in hover and forward flight without rotor-state data is developed. The : structure of the model is determined through consideration of the important : dynamic modes ...

77 FR 75073 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-19

... Deutschland GmbH Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Supplemental notice... proposed airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model BO-105A, BO- 105C... airworthiness directive (AD): Eurocopter Deutschland GmbH: Docket No. FAA-2011-1285; Directorate Identifier 2010...

NASA Aircraft on ramp (Aerial view) Sides: (L) QSRA (R) C-8A AWJSRA - Back to Front: CV-990 (711)

NASA Technical Reports Server (NTRS)

1981-01-01

NASA Aircraft on ramp (Aerial view) Sides: (L) QSRA (R) C-8A AWJSRA - Back to Front: CV-990 (711) C-141 KAO, CV-990 (712) Galileo, T-38, YO-3A, Lear Jet, X-14, U-2, OH-6, CH-47, SH-3G, RSRA, AH-1G, XV-15, UH-1H

Simulated Guide Stars: Adapting the Robo-AO Telescope Simulator to UH 88”

NASA Astrophysics Data System (ADS)

Ashcraft, Jaren; Baranec, Christoph

2018-01-01

Robo-AO is an autonomous adaptive optics system that is in development for the UH 88” Telescope on the Mauna Kea Observatory. This system is capable of achieving near diffraction limited imaging for astronomical telescopes, and has seen successful deployment and use at the Palomar and Kitt Peak Observatories previously. A key component of this system, the telescope simulator, will be adapted from the Palomar Observatory design to fit the UH 88” Telescope. The telescope simulator will simulate the exit pupil of the UH 88” telescope so that the greater Robo-AO system can be calibrated before observing runs. The system was designed in Code V, and then further improved upon in Zemax for later development. Alternate design forms were explored for the potential of adapting the telescope simulator to the NASA Infrared Telescope Facility, where simulating the exit pupil of the telescope proved to be more problematic. A proposed design composed of solely catalog optics was successfully produced for both telescopes, and they await assembly as time comes to construct the new Robo-AO system.

A Summary of DOD-Sponsored Research Performed at NASA Langley's Impact Dynamics Research Facility

NASA Technical Reports Server (NTRS)

Jackson, Karen E.; Boitnott, Richard L.; Fasanella, Edwin L.; Jones, Lisa E.; Lyle, Karen H.

2004-01-01

The Impact Dynamics Research Facility (IDRF) is a 240-ft.-high gantry structure located at NASA Langley Research Center in Hampton, Virginia. The IDRF was originally built in the early 1960's for use as a Lunar Landing Research Facility. As such, the facility was configured to simulate the reduced gravitational environment of the Moon, allowing the Apollo astronauts to practice lunar landings under realistic conditions. In 1985, the IDRF was designated a National Historic Landmark based on its significant contributions to the Apollo Moon Landing Program. In the early 1970's the facility was converted into its current configuration as a full-scale crash test facility for light aircraft and rotorcraft. Since that time, the IDRF has been used to perform a wide variety of impact tests on full-scale aircraft, airframe components, and space vehicles in support of the General Aviation (GA) aircraft industry, the U.S. Department of Defense (DOD), the rotorcraft industry, and the NASA Space program. The objectives of this paper are twofold: to describe the IDRF facility and its unique capabilities for conducting structural impact testing, and to summarize the impact tests performed at the IDRF in support of the DOD. These tests cover a time period of roughly 2 1/2 decades, beginning in 1975 with the full-scale crash test of a CH-47 Chinook helicopter, and ending in 1999 with the external fuel system qualification test of a UH-60 Black Hawk helicopter. NASA officially closed the IDRF in September 2003; consequently, it is important to document the past contributions made in improved human survivability and impact tolerance through DOD-sponsored research performed at the IDRF.

Mission Suitability Testing of an Aircraft Simulator. Technical Report No. 75-12.

ERIC Educational Resources Information Center

Caro, Paul W.; And Others

The report describes a study conducted to evaluate Device 2B24, which simulates the UH-1 helicopter and an instrument flight environment, and to determine its suitability for cost-effectively accomplishing the instrument phase of Army rotary wing flight training and facilitating UH-1 helicopter transition training, aviator proficiency evaluation,…

Exploratory Investigation of Aerodynamic Characteristics of Helicopter Tail Boom Cross-Section Models with Passive Venting

NASA Technical Reports Server (NTRS)

Banks, Daniel W.; Kelley, Henry L.

2000-01-01

Two large-scale, two-dimensional helicopter tail boom models were used to determine the effects of passive venting on boom down loads and side forces in hovering crosswind conditions. The models were oval shaped and trapezoidal shaped. Completely porous and solid configurations, partial venting in various symmetric and asymmetric configurations, and strakes were tested. Calculations were made to evaluate the trends of venting and strakes on power required when applied to a UH-60 class helicopter. Compared with the UH-60 baseline, passive venting reduced side force but increased down load at flow conditions representing right sideward flight. Selective asymmetric venting resulted in side force benefits close to the fully porous case. Calculated trends on the effects of venting on power required indicated that the high asymmetric oval configuration was the most effective venting configuration for side force reduction, and the high asymmetric with a single strake was the most effective for overall power reduction. Also, curves of side force versus flow angle were noticeable smoother for the vented configurations compared with the solid baseline configuration; this indicated a potential for smoother flight in low-speed crosswind conditions.

78 FR 52412 - Airworthiness Directives; Eurocopter Deutschland GmbH (ECD) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

... Airworthiness Directives; Eurocopter Deutschland GmbH (ECD) Helicopters AGENCY: Federal Aviation Administration... new airworthiness directive (AD): 2013-16-20 Eurocopter Deutschland GmbH (ECD): Amendment 39-17558... the EASA AD at http://www.regulations.gov in Docket No. FAA-2013-0020. (h) Subject Joint Aircraft...

14 CFR 36.11 - Acoustical change: Helicopters.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Acoustical change: Helicopters. 36.11...: Helicopters. This section applies to all helicopters in the primary, normal, transport, and restricted... appendix H of this part, or, for helicopters having a maximum certificated takeoff weight of not more than...

14 CFR 36.11 - Acoustical change: Helicopters.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Acoustical change: Helicopters. 36.11...: Helicopters. This section applies to all helicopters in the primary, normal, transport, and restricted... appendix H of this part, or, for helicopters having a maximum certificated takeoff weight of not more than...

14 CFR 36.11 - Acoustical change: Helicopters.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Acoustical change: Helicopters. 36.11...: Helicopters. This section applies to all helicopters in the primary, normal, transport, and restricted... appendix H of this part, or, for helicopters having a maximum certificated takeoff weight of not more than...

14 CFR 36.11 - Acoustical change: Helicopters.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Acoustical change: Helicopters. 36.11...: Helicopters. This section applies to all helicopters in the primary, normal, transport, and restricted... appendix H of this part, or, for helicopters having a maximum certificated takeoff weight of not more than...

14 CFR 36.11 - Acoustical change: Helicopters.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Acoustical change: Helicopters. 36.11...: Helicopters. This section applies to all helicopters in the primary, normal, transport, and restricted... appendix H of this part, or, for helicopters having a maximum certificated takeoff weight of not more than...

KSC-98pc776

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- A beach ball-sized infrared camera, part of the Forward Looking Infrared Radar (FLIR), has been mounted on the right siderail of NASA's Huey UH-1 helicopter. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR also includes a real-time television monitor and recorder installed inside the helicopter. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. The Kennedy Space Center (KSC) security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

A review of ice accretion data from a model rotor icing test and comparison with theory

NASA Technical Reports Server (NTRS)

Britton, Randall K.; Bond, Thomas H.

1991-01-01

An experiment was conducted by the Helicopter Icing Consortium (HIC) in the NASA Lewis Icing Research Tunnel (IRT) in which a 1/6 scale fuselage model of a UH-60A Black Hawk helicopter with a generic rotor was subjected to a wide range of icing conditions. The HIC consists of members from NASA, Bell Helicopter, Boeing Helicopter, McDonnell Douglas Helicopters, Sikorsky Aircraft, and Texas A&M University. Data was taken in the form of rotor torque, internal force balance measurements, blade strain gage loading, and two dimensional ice shape tracings. A review of the ice shape data is performed with special attention given to repeatability and correctness of trends in terms of radial variation, rotational speed, icing time, temperature, liquid water content, and volumetric median droplet size. Moreover, an indepth comparison between the experimental data and the analysis of NASA's ice accretion code LEWICE is given. Finally, conclusions are drawn as to the quality of the ice accretion data and the predictability of the data base as a whole. Recommendations are also given for improving data taking technique as well as potential future work.

78 FR 67020 - Airworthiness Directives; Eurocopter Deutschland GmbH (ECD) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-08

... Airworthiness Directives; Eurocopter Deutschland GmbH (ECD) Helicopters AGENCY: Federal Aviation Administration... the AD Docket at http://www.regulations.gov . (h) Subject Joint Aircraft Service Component (JASC) Code..., of Eurocopter Deutschland GmbH Flight Manual BO 105 C/CS, Revision 5, dated March 12, 2010. (ii...

78 FR 37150 - Airworthiness Directives; Eurocopter Deutschland GmbH (ECD) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-20

... Deutschland GmbH (ECD) Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of...): Eurocopter Deutschland GmbH (ECD): Docket No. FAA-2013-0519; Directorate Identifier 2010-SW-068-AD. (a... European Aviation Safety Agency AD No. 2010-0128, dated June 25, 2010. (h) Subject Joint Aircraft Service...

XV-15 tilt rotor ship #1 and #2 parked on NASA ramp

NASA Image and Video Library

1981-04-03

The XV-15 tilt rotor ships #1 and #2 parked on the NASA Dryden Flight Research Center ramp. The XV-15s, manufactured by Bell, were involved in limited research at Dryden in 1980 and 1981. The development of the XV-15 Tiltrotor research aircraft was initiated in 1973 with joint Army/NASA funding as a "proof of concept", or "technology demonstrator" program, with two aircraft being built by Bell Helicopter Textron (BHT) in 1977. The aircraft are powered by twin Lycoming T-53 turboshaft engines that are connected by a cross-shaft and drive three-bladed, 25 ft diameter metal rotors (the size extensively tested in a wind tunnel). The engines and main transmissions are located in wingtip nacelles to minimize the operational loads on the cross-shaft system and, with the rotors, tilt as a single unit. For takeoff, the proprotors and their engines are used in the straight-up position where the thrust is directed downward. The XV-15 then climbs vertically into the air like a helicopter. In this VTOL mode, the vehicle can lift off and hover for approximately one hour. Once off the ground, the XV-15 has the ability to fly in one of two different modes. It can fly as a helicopter, in the partially converted airplane mode. The XV-15 can also then convert from the helicopter mode to the airplane mode. This is accomplished by continuous rotation of the proprotors from the helicopter rotor position to the conventional airplane propeller position. During the ten to fifteen second conversion period, the aircraft speed increases and lift is transferred from the rotors to the wing. To land, the proprotors are rotated up to the helicopter rotor position and flown as a helicopter to a vertical landing.

Orion Launch from Helicopter - Aerials

NASA Image and Video Library

2014-12-05

This helicopter view of the NASA Causeway connecting NASA's Kennedy Space Center with Cape Canaveral Air Force Staton shows the thousands of vehicles parked where guests gather to see the launch of the Orion Flight Test.

A comparison of lightning and nuclear electromagnetic pulse response of a helicopter

NASA Technical Reports Server (NTRS)

Easterbrook, C. C.; Perala, R. A.

1984-01-01

A numerical modeling technique is utilized to investigate the response of a UH-60A helicopter to both lightning and nuclear electromagnetic pulses (NEMP). The analytical approach involves the three-dimensional time domain finite-difference solutions of Maxwell's equations. Both the external currents and charges as well as the internal electromagnetic fields and cable responses are computed. Results of the analysis indicate that, in general, the short circuit current on internal cables is larger for lightning, whereas the open-circuit voltages are slightly higher for NEMP. The lightning response is highly dependent upon the rise time of the injected current as was expected. The analysis shows that a coupling levels to cables in a helicopter are 20 to 30 dB larger than those observed in fixed-wing aircraft.

Recent Langley helicopter acoustics contributions

NASA Technical Reports Server (NTRS)

Morgan, Homer G.; Pao, S. P.; Powell, C. A.

1988-01-01

The helicopter acoustics program at NASA Langley has included technology for elements of noise control ranging from sources of noise to receivers of noise. The scope of Langley contributions for about the last decade is discussed. Specifically, the resolution of two certification noise quantification issues by subjective acoustics research, the development status of the helicopter system noise prediction program ROTONET are reviewed and the highlights from research on blade rotational, broadband, and blade vortex interaction noise sources are presented. Finally, research contributions on helicopter cabin (or interior) noise control are presented. A bibliography of publications from the Langley helicopter acoustics program for the past 10 years is included.

ARC-1981-AC81-0122-1

NASA Image and Video Library

1981-02-25

NASA Aircraft on ramp (Aerial view) Sides: (L) QSRA (R) C-8A AWJSRA - Back to Front: CV-990 (711) C-141 KAO, CV-990 (712) Galileo, T-38, YO-3A, Lear Jet, X-14, U-2, OH-6, CH-47, SH-3G, RSRA, AH-1G, XV-15, UH-1H

Preliminary design features of the RASCAL - A NASA/Army rotorcraft in-flight simulator

NASA Technical Reports Server (NTRS)

Aiken, Edwin W.; Jacobsen, Robert A.; Eshow, Michelle M.; Hindson, William S.; Doane, Douglas H.

1992-01-01

Salient design features of a new NASA/Army research rotorcraft - the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) - are described. Using a UH-60A Black Hawk helicopter as a baseline vehicle, the RASCAL will be a flying laboratory capable of supporting the research requirements of major NASA and Army guidance, control, and display research programs. The paper describes the research facility requirements of these programs together with other critical constraints on the design of the research system, including safety-of-flight. Research program schedules demand a phased development approach, wherein specific research capability milestones are met and flight research projects are flown throughout the complete development cycle of the RASCAL. This development approach is summarized, and selected features of the research system are described. The research system includes a full-authority, programmable, fault-tolerant/fail-safe, fly-by-wire flight control system and a real-time obstacle detection and avoidance system which will generate low-latitude guidance commands to the pilot on a wide field-of-view, color helmet-mounted display.

Preliminary design features of the RASCAL: A NASA /Army rotorcraft in-flight simulator

NASA Technical Reports Server (NTRS)

Aiken, Edwin W.; Jacobsen, Robert A.; Eshow, Michelle M.; Hindson, William S.; Doane, Douglas H.

1993-01-01

Salient design features of a new NASA/Army research rotorcraft - the Rotorcraft-Aircrew Systems Concepts Airborne Laboratory (RASCAL) - are described. Using a UH-60A Black Hawk helicopter as a baseline vehicle, the RASCAL will be a flying laboratory capable of supporting the research requirements of major NASA and Army guidance, control, and display research programs. The paper describes the research facility requirements of these programs together with other critical constraints on the design of the research system, including safety-of-flight. Research program schedules demand a phased development approach, wherein specific research capability milestones are met and flight research projects are flown throughout the complete development cycle of the RASCAL. This development approach is summarized, and selected features of the research system are described. The research system includes a full-authority, programmable, fault-tolerant/fail-safe, fly-by-wire flight control system and a real-time obstacle detection and avoidance system which will generate low-altitude guidance commands to the pilot on a wide field-of-view, color helmet-mounted display.

Flight Test Evaluation of a Nonlinear Hub Spring on a UH-1H Helicopter.

DTIC Science & Technology

1981-04-01

APPLIED TECHNOLOGY LABORATORY POSITION STATEMENT This report documents the engineering analysis, development , arnd flight test of a non- linger hub...order to develop a design criteria to ensure that mast loads can be sustained during in-flight flapping stop contact. In addition, a comparison of the...LIST OF ILLUSTRATIONS Figure Page 1 Rotor blade-element aerodynamic coefficients used in ARHF01 .................................. 18 2 Rotor model on

Validation of helicopter noise prediction techniques

NASA Technical Reports Server (NTRS)

Succi, G. P.

1981-01-01

The current techniques of helicopter rotor noise prediction attempt to describe the details of the noise field precisely and remove the empiricisms and restrictions inherent in previous methods. These techniques require detailed inputs of the rotor geometry, operating conditions, and blade surface pressure distribution. The purpose of this paper is to review those techniques in general and the Farassat/Nystrom analysis in particular. The predictions of the Farassat/Nystrom noise computer program, using both measured and calculated blade surface pressure data, are compared to measured noise level data. This study is based on a contract from NASA to Bolt Beranek and Newman Inc. with measured data from the AH-1G Helicopter Operational Loads Survey flight test program supplied by Bell Helicopter Textron.

Mars Helicopter (Artist's Concept)

NASA Image and Video Library

2018-05-25

This artist concept shows the Mars Helicopter, a small, autonomous rotorcraft, which will travel with NASA's Mars 2020 rover mission, currently scheduled to launch in July 2020, to demonstrate the viability and potential of heavier-than-air vehicles on the Red Planet. https://photojournal.jpl.nasa.gov/catalog/PIA22460

Advanced Control System Increases Helicopter Safety

NASA Technical Reports Server (NTRS)

2008-01-01

With support and funding from a Phase II NASA SBIR project from Ames Research Center, Hoh Aeronautics Inc. (HAI), of Lomita, California, produced HeliSAS, a low-cost, lightweight, attitude-command-attitude-hold stability augmentation system (SAS) for civil helicopters and unmanned aerial vehicles. HeliSAS proved itself in over 160 hours of flight testing and demonstrations in a Robinson R44 Raven helicopter, a commercial helicopter popular with news broadcasting and police operations. Chelton Flight Systems, of Boise, Idaho, negotiated with HAI to develop, market, and manufacture HeliSAS, now available as the Chelton HeliSAS Digital Helicopter Autopilot.

UH-1H Flat Rate Manual. Volume 2

DTIC Science & Technology

1975-07-01

o o Ox IA «A IAVO o O O O O rococo co co rococo co co CO CO CO CO CO CO CO CO CO IAIAIA IA IA IT» »A IA UMA i ■ XX o 4» « § « * * ■ 2...OOO O O O O O rococo co co co co co rococo co co co co co 1 WIAIA IA U\\ ITilA IA s If r% ■H fjg X a ! °* i Q i F o M as 1 V. 3 I -372

Application of nonlinear transformations to automatic flight control

NASA Technical Reports Server (NTRS)

Meyer, G.; Su, R.; Hunt, L. R.

1984-01-01

The theory of transformations of nonlinear systems to linear ones is applied to the design of an automatic flight controller for the UH-1H helicopter. The helicopter mathematical model is described and it is shown to satisfy the necessary and sufficient conditions for transformability. The mapping is constructed, taking the nonlinear model to canonical form. The performance of the automatic control system in a detailed simulation on the flight computer is summarized.

Changes in Helicopter Reliability/Maintainability Characteristics Over Time. Volume 2. Data Submitted by Helicopter Manufacturers

DTIC Science & Technology

1975-03-01

Quarterly Evaluation Report [ CH -54A] . . . S. TI. Eighth (8th) Quarterly CH -53 Readiness Report . . .. S-79 *.hrc.e parInation sequences are used In this...Total & Subsystem R Growth Parameters Table 2 CJF-46 Total Aircraft R~ Growth Statiatics Table 5 C7O-46 Subsystem R Growth Statistics Table 5 CH -46...UH-1 Navy. H-2 Navy, *-3 Navy# e OH-6 Army, H-19 Navy, H-19 Army, H-21 Air Force, H-21 Army. H-34 Army, H-34 Navy, H-37 Navy. H-37 Army, H-46 Navy, CH

KSC-98pc781

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- A beach ball-sized infrared camera, part of the Forward Looking Infrared Radar (FLIR), has been mounted on the right siderail of NASA's Huey UH-1 helicopter and is being used to scan a large area of Volusia County, Florida, where a fire burns. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR also includes a real-time television monitor and recorder installed inside the helicopter. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. The Kennedy Space Center (KSC) security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

KSC-98pc778

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- A forest fire burning in Volusia County, Florida, is clearly visible from NASA's Huey UH-1 helicopter. The helicopter has been outfitted with a Forward Looking Infrared Radar (FLIR) and a portable global positioning satellite (GPS) system to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR includes a beach ball-sized infrared camera that is mounted on the helicopter's right siderail and a real-time television monitor and recorder installed inside. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. The Kennedy Space Center (KSC) security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

KSC-98pc774

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- Sgt. Mark Hines, of Kennedy Space Center (KSC) Security, checks out equipment used to operate the Forward Looking Infrared Radar (FLIR) installed on NASA's Huey UH-1 helicopter. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR includes a beach ball-sized infrared camera that is mounted on the helicopter's right siderail and a real-time television monitor and recorder installed inside. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. KSC's security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

KSC-98pc775

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- NASA's Huey UH-1 helicopter lands at the Shuttle Landing Facility to pick up Kennedy Space Center (KSC) Security personnel who operate the Forward Looking Infrared Radar (FLIR) installed on board. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR includes a beach ball-sized infrared camera that is mounted on the helicopter's right siderail and a real-time television monitor and recorder installed inside. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. KSC's security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

KSC-98pc777

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- A beach ball-sized infrared camera, part of the Forward Looking Infrared Radar (FLIR), has been mounted on the right siderail of NASA's Huey UH-1 helicopter. A KSC pilot prepares to fly the helicopter, which has also been outfitted with a portable global positioning satellite (GPS) system, to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR also includes a real-time television monitor and recorder installed inside the helicopter. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. The Kennedy Space Center (KSC) security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

KSC-98pc779

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- A beach ball-sized infrared camera, part of the Forward Looking Infrared Radar (FLIR), has been mounted on the right siderail of NASA's Huey UH-1 helicopter and is being used to search for fires in Volusia County, Florida. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR also includes a real-time television monitor and recorder installed inside the helicopter. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. The Kennedy Space Center (KSC) security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter

Training Presentation for NASA Civil Helicopter Safety Website

NASA Technical Reports Server (NTRS)

Iseler, Laura

2002-01-01

NASA civil helicopter safety News & Updates include the following: Mar. 2002. The Air Medical Operations Survey has been completed! Check it out! Also accessible via the Mission pages under Air Medical Mission. Air Medical and Law Enforcement Mission pages have been added. They are accessible via the Mission pages. The Public Use, Personal, Offshore, Law Enforcement, External Load, Business and Gyro accident pages (accessable via the Mission page) have been updated. Feb. 2002. A Words of Wisdom section has been added. You can access it by clicking the Library button. A link to a Corporate Accident Response Plan has been added to the Accident page. The AMs, Aerial Application and Instruction accident pages (accessable via the Mission page) have been updated. Jan. 2002. A new searchable safety article database has been added. You can access it by clicking the Library button. The 2001 accident summaries have been updated and the statistics have been compiled - check it out by clicking the accident tab to the left. Dec. 2001. Please read the FAA Administrator's memo regarding the latest FBI warning. 3ee the FAA column - Fall 2001 Read it now!

Assessment of simulation fidelity using measurements of piloting technique in flight

NASA Technical Reports Server (NTRS)

Ferguson, S. W.; Clement, W. F.; Cleveland, W. B.; Key, D. L.

1984-01-01

The U.S. Army and NASA have undertaken the systematic validation of a ground-based piloted simulator for the UH-60A helicopter. The results of previous handling quality and task performance flight tests for this helicopter have been used as a data base for evaluating the fidelity of the present simulation, which is being conducted at the NASA Ames Research Center's Vertical Motion Simulator. Such nap-of-the-earth piloting tasks as pop-up, hover turn, dash/quick stop, sidestep, dolphin, and slalom, have been investigated. It is noted that pilot simulator performance is significantly and quantifiable degraded by comparison with flight test results for the same tasks.

78 FR 78710 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-27

... attached loads, and subsequent loss of helicopter control. DATES: This AD is effective January 31, 2014... of the boom and attached loads, and subsequent loss of helicopter control. The NPRM was prompted by... the loss of the boom and attached loads. According to EASA, boom P/Ns 44301-500 and 44307-500-1 are of...

Contingency power concepts for helicopter turboshaft engine

NASA Technical Reports Server (NTRS)

Hirschkron, R.; Davis, R. H.; Goldstein, D. N.; Haynes, J. F.; Gauntner, J. W.

1984-01-01

Twin helicopter engines are often sized by power requirement of safe mission completion after the failure of one of the two engines. This study was undertaken for NASA Lewis by General Electric Co. to evaluate the merits of special design features to provide a 2-1/2 minute Contingency Power rating, permitting an engine size reduction. The merits of water injection, cooling flow modulation, throttle push and an auxiliary power plant were evaluated using military life cycle cost (LCC) and commercial helicopter direct operating cost (DOC) merit factors in a rubber engine/rubber aircraft scenario.

Detached Eddy Simulation of the UH-60 Rotor Wake Using Adaptive Mesh Refinement

NASA Technical Reports Server (NTRS)

Chaderjian, Neal M.; Ahmad, Jasim U.

2012-01-01

Time-dependent Navier-Stokes flow simulations have been carried out for a UH-60 rotor with simplified hub in forward flight and hover flight conditions. Flexible rotor blades and flight trim conditions are modeled and established by loosely coupling the OVERFLOW Computational Fluid Dynamics (CFD) code with the CAMRAD II helicopter comprehensive code. High order spatial differences, Adaptive Mesh Refinement (AMR), and Detached Eddy Simulation (DES) are used to obtain highly resolved vortex wakes, where the largest turbulent structures are captured. Special attention is directed towards ensuring the dual time accuracy is within the asymptotic range, and verifying the loose coupling convergence process using AMR. The AMR/DES simulation produced vortical worms for forward flight and hover conditions, similar to previous results obtained for the TRAM rotor in hover. AMR proved to be an efficient means to capture a rotor wake without a priori knowledge of the wake shape.

Testing of YUH-61A helicopter transmission in NASA Lewis 2240-kW (3000-hp facility

NASA Technical Reports Server (NTRS)

Mitchell, A. M.; Oswald, F. B.; Schuller, F. T.

1986-01-01

A helicopter transmission that was being considered for the Army's Utility Tactical Transport Attack System (UTTAS) was tested in the NASA Lewis 2240-kW (3000-hp) test facility to obtain the transmission's operational data. The results will form a vibration and efficiency data base for evaluation similar-class helicopter transmissions. The transmission's mechanical efficiency was determined to be 98.7 percent at its rated power level of 2080 kW (2792 hp). At power levels up to 113 percent of rated the transmission displayed 56 percent higher vibration acceleration levels on the right input than on the left input. Both vibration signature analysis and final visual inspection indicated that the right input spiral-bevel gear had poor contact patterns. The highest vibration meter level was 52 g's rms at the accessory gear, which had free-wheeling gearsets. At 113 percent power and 100 percent rated speed the vibration meter levels generally ranged from 3 to 25 g's rms.

Helicopter Non-Unique Trim Strategies for Blade-Vortex Interaction (BVI) Noise Reduction

NASA Technical Reports Server (NTRS)

Malpica, Carlos; Greenwood, Eric; Sim, Ben W.

2016-01-01

An acoustics parametric analysis of the effect of fuselage drag and pitching moment on the Blade-Vortex Interaction (BVI) noise radiated by a medium lift helicopter (S-70UH-60) in a descending flight condition was conducted. The comprehensive analysis CAMRAD II was used for the calculation of vehicle trim, wake geometry and integrated air loads on the blade. The acoustics prediction code PSU-WOPWOP was used for calculating acoustic pressure signatures for a hemispherical grid centered at the hub. This paper revisits the concept of the X-force controller for BVI noise reduction, and investigates its effectiveness on an S-70 helicopter. The analysis showed that further BVI noise reductions were achievable by controlling the fuselage pitching moment. Reductions in excess of 6 dB of the peak BVI noise radiated towards the ground were demonstrated by compounding the effect of airframe drag and pitching moment simultaneously.

Modeling of UH-60A Hub Accelerations with Neural Networks

NASA Technical Reports Server (NTRS)

Kottapalli, Sesi

2002-01-01

Neural network relationships between the full-scale, flight test hub accelerations and the corresponding three N/rev pilot floor vibration components (vertical, lateral, and longitudinal) are studied. The present quantitative effort on the UH-60A Black Hawk hub accelerations considers the lateral and longitudinal vibrations. An earlier study had considered the vertical vibration. The NASA/Army UH-60A Airloads Program flight test database is used. A physics based "maneuver-effect-factor (MEF)", derived using the roll-angle and the pitch-rate, is used. Fundamentally, the lateral vibration data show high vibration levels (up to 0.3 g's) at low airspeeds (for example, during landing flares) and at high airspeeds (for example, during turns). The results show that the advance ratio and the gross weight together can predict the vertical and the longitudinal vibration. However, the advance ratio and the gross weight together cannot predict the lateral vibration. The hub accelerations and the advance ratio can be used to satisfactorily predict the vertical, lateral, and longitudinal vibration. The present study shows that neural network based representations of all three UH-60A pilot floor vibration components (vertical, lateral, and longitudinal) can be obtained using the hub accelerations along with the gross weight and the advance ratio. The hub accelerations are clearly a factor in determining the pilot vibration. The present conclusions potentially allow for the identification of neural network relationships between the experimental hub accelerations obtained from wind tunnel testing and the experimental pilot vibration data obtained from flight testing. A successful establishment of the above neural network based link between the wind tunnel hub accelerations and the flight test vibration data can increase the value of wind tunnel testing.

Adding In-Plane Flexibility to the Equations of Motion of a Single Rotor Helicopter

NASA Technical Reports Server (NTRS)

Curtiss, H. C., Jr.

2000-01-01

This report describes a way to add the effects of main rotor blade flexibility in the in- plane or lead-lag direction to a large set of non-linear equations of motion for a single rotor helicopter with rigid blades(l). Differences between the frequency of the regressing lag mode predicted by the equations of (1) and that measured in flight (2) for a UH-60 helicopter indicate that some element is missing from the analytical model of (1) which assumes rigid blades. A previous study (3) noted a similar discrepancy for the CH-53 helicopter. Using a relatively simple analytical model in (3), compared to (1), it was shown that a mechanical lag damper increases significantly the coupling between the rigid lag mode and the first flexible mode. This increased coupling due to a powerful lag damper produces an increase in the lowest lag frequency when viewed in a frame rotating with the blade. Flight test measurements normally indicate the frequency of this mode in a non-rotating or fixed frame. This report presents the additions necessary to the full equations of motion, to include main rotor blade lag flexibility. Since these additions are made to a very complex nonlinear dynamic model, in order to provide physical insight, a discussion of the results obtained from a simplified set of equations of motion is included. The reduced model illustrates the physics involved in the coupling and should indicate trends in the full model.

NASTRAN Modeling of Flight Test Components for UH-60A Airloads Program Test Configuration

NASA Technical Reports Server (NTRS)

Idosor, Florentino R.; Seible, Frieder

1993-01-01

Based upon the recommendations of the UH-60A Airloads Program Review Committee, work towards a NASTRAN remodeling effort has been conducted. This effort modeled and added the necessary structural/mass components to the existing UH-60A baseline NASTRAN model to reflect the addition of flight test components currently in place on the UH-60A Airloads Program Test Configuration used in NASA-Ames Research Center's Modern Technology Rotor Airloads Program. These components include necessary flight hardware such as instrument booms, movable ballast cart, equipment mounting racks, etc. Recent modeling revisions have also been included in the analyses to reflect the inclusion of new and updated primary and secondary structural components (i.e., tail rotor shaft service cover, tail rotor pylon) and improvements to the existing finite element mesh (i.e., revisions of material property estimates). Mode frequency and shape results have shown that components such as the Trimmable Ballast System baseplate and its respective payload ballast have caused a significant frequency change in a limited number of modes while only small percent changes in mode frequency are brought about with the addition of the other MTRAP flight components. With the addition of the MTRAP flight components, update of the primary and secondary structural model, and imposition of the final MTRAP weight distribution, modal results are computed representative of the 'best' model presently available.

Navier-Stokes Simulation of UH-60A Rotor/Wake Interaction Using Adaptive Mesh Refinement

NASA Technical Reports Server (NTRS)

Chaderjian, Neal M.

2017-01-01

Time-dependent Navier-Stokes simulations have been carried out for a flexible UH-60A rotor in forward flight, where the rotor wake interacts with the rotor blades. These flow conditions involved blade vortex interaction and dynamic stall, two common conditions that occur as modern helicopter designs strive to achieve greater flight speeds and payload capacity. These numerical simulations utilized high-order spatial accuracy and delayed detached eddy simulation. Emphasis was placed on understanding how improved rotor wake resolution affects the prediction of the normal force, pitching moment, and chord force of the rotor. Adaptive mesh refinement was used to highly resolve the turbulent rotor wake in a computationally efficient manner. Moreover, blade vortex interaction was found to trigger dynamic stall. Time-dependent flow visualization was utilized to provide an improved understanding of the numerical and physical mechanisms involved with three-dimensional dynamic stall.

KSC-98pc780

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- Sgt. Mark Hines, of Kennedy Space Center (KSC) Security, points out a view of a fire on the Forward Looking Infrared Radar (FLIR) video screen to Greg Dunn, of Florida's Division of Forestry, as KSC pilots fly NASA's Huey UH-1 helicopter over fires burning in Volusia County, Florida. The FLIR includes a beach-ball sized infrared camera that is mounted on the helicopter's right siderail and a real-time TV monitor and recorder installed inside. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support the Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. KSC's security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter.

The NASA modern technology rotors program

NASA Technical Reports Server (NTRS)

Watts, M. E.; Cross, J. L.

1986-01-01

Existing data bases regarding helicopters are based on work conducted on 'old-technology' rotor systems. The Modern Technology Rotors (MTR) Program is to provide extensive data bases on rotor systems using present and emerging technology. The MTR is concerned with modern, four-bladed, rotor systems presently being manufactured or under development. Aspects of MTR philosophy are considered along with instrumentation, the MTR test program, the BV 360 Rotor, and the UH-60 Black Hawk. The program phases include computer modelling, shake test, model-scale test, minimally instrumented flight test, extensively pressure-instrumented-blade flight test, and full-scale wind tunnel test.

29 CFR 1910.183 - Helicopters.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 29 Labor 5 2014-07-01 2014-07-01 false Helicopters. 1910.183 Section 1910.183 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Materials Handling and Storage § 1910.183 Helicopters. (a) [Reserved...) Housekeeping. Good housekeeping shall be maintained in all helicopter loading and unloading areas. (h) Load...

29 CFR 1910.183 - Helicopters.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 29 Labor 5 2013-07-01 2013-07-01 false Helicopters. 1910.183 Section 1910.183 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Materials Handling and Storage § 1910.183 Helicopters. (a) [Reserved...) Housekeeping. Good housekeeping shall be maintained in all helicopter loading and unloading areas. (h) Load...

29 CFR 1910.183 - Helicopters.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 29 Labor 5 2012-07-01 2012-07-01 false Helicopters. 1910.183 Section 1910.183 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Materials Handling and Storage § 1910.183 Helicopters. (a) [Reserved...) Housekeeping. Good housekeeping shall be maintained in all helicopter loading and unloading areas. (h) Load...

CFD Based Computations of Flexible Helicopter Blades for Stability Analysis

NASA Technical Reports Server (NTRS)

Guruswamy, Guru P.

2011-01-01

As a collaborative effort among government aerospace research laboratories an advanced version of a widely used computational fluid dynamics code, OVERFLOW, was recently released. This latest version includes additions to model flexible rotating multiple blades. In this paper, the OVERFLOW code is applied to improve the accuracy of airload computations from the linear lifting line theory that uses displacements from beam model. Data transfers required at every revolution are managed through a Unix based script that runs jobs on large super-cluster computers. Results are demonstrated for the 4-bladed UH-60A helicopter. Deviations of computed data from flight data are evaluated. Fourier analysis post-processing that is suitable for aeroelastic stability computations are performed.

An analytically linearized helicopter model with improved modeling accuracy

NASA Technical Reports Server (NTRS)

Jensen, Patrick T.; Curtiss, H. C., Jr.; Mckillip, Robert M., Jr.

1991-01-01

An analytically linearized model for helicopter flight response including rotor blade dynamics and dynamic inflow, that was recently developed, was studied with the objective of increasing the understanding, the ease of use, and the accuracy of the model. The mathematical model is described along with a description of the UH-60A Black Hawk helicopter and flight test used to validate the model. To aid in utilization of the model for sensitivity analysis, a new, faster, and more efficient implementation of the model was developed. It is shown that several errors in the mathematical modeling of the system caused a reduction in accuracy. These errors in rotor force resolution, trim force and moment calculation, and rotor inertia terms were corrected along with improvements to the programming style and documentation. Use of a trim input file to drive the model is examined. Trim file errors in blade twist, control input phase angle, coning and lag angles, main and tail rotor pitch, and uniform induced velocity, were corrected. Finally, through direct comparison of the original and corrected model responses to flight test data, the effect of the corrections on overall model output is shown.

Analytic investigation of helicopter rotor blade appended aeroelastic devices

NASA Technical Reports Server (NTRS)

Bielawa, Richard L.

1984-01-01

Analytic evaluations of four different passive aeroelastic devices appended to helicopter rotor blades are presented. The devices consist of a passive tuned tab, a control coupled tab, an all-flying tip and a harmonic dilational airfoil tip. Each device was conceived for improving either aerodynamic performance or reducing vibratory control loads or hub shears. The evaluation was performed using a comprehensive rotor aeroelastic analysis (the G400PA code with appropriate modifications), together with data for a realistic helicopter rotor blade (the UH-60A Blackhawk), in high speed flight (90 m/s, 175 kts). The results of this study show that significant performance (L/(D sub e)) gains can be achieved with the all-flying free tip. Results from the harmonic dilational airfoil tip show the potential for moderate improvements in L/(D sub e). Finally, the results for the passive tuned tab and the control coupled tab, as configured for this study, show these devices to be impractical. Sections are included which describe the operation of each device, the required G400PA modifications, and the detailed results obtained for each device.

The Development of the CONDUIT Advanced Control System Design and Evaluation Interface with a Case Study Application to an Advanced Fly by Wire Helicopter Design

NASA Technical Reports Server (NTRS)

Colbourne, Jason

1999-01-01

This report details the development and use of CONDUIT (Control Designer's Unified Interface). CONDUIT is a design tool created at Ames Research Center for the purpose of evaluating and optimizing aircraft control systems against handling qualities. Three detailed design problems addressing the RASCAL UH-60A Black Hawk are included in this report to show the application of CONDUIT to helicopter control system design.

78 FR 60182 - Airworthiness Directives; Bell Helicopter Textron, Inc., Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-01

... Helicopter Textron, Inc. (Bell), Model 214B, 214B-1, and 214ST helicopters. This AD requires creating a... and 214B-1 helicopters with a certain spindle installed. The NPRM proposed to require creating a...

Orion Launch from Helicopter - Aerials

NASA Image and Video Library

2014-12-05

This helicopter view of Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida shows the United Launch Alliance Delta IV Heavy rocket as it stands ready to boost NASA's Orion spacecraft on a 4.5-hour mission.

Bearing restoration by grinding

NASA Technical Reports Server (NTRS)

Hanau, H.; Parker, R. J.; Zaretsky, E. V.; Chen, S. M.; Bull, H. L.

1976-01-01

A joint program was undertaken by the NASA Lewis Research Center and the Army Aviation Systems Command to restore by grinding those rolling-element bearings which are currently being discarded at aircraft engine and transmission overhaul. Three bearing types were selected from the UH-1 helicopter engine (T-53) and transmission for the pilot program. No bearing failures occurred related to the restoration by grinding process. The risk and cost of a bearing restoration by grinding programs was analyzed. A microeconomic impact analysis was performed.

78 FR 56592 - Airworthiness Directives; Bell Helicopter Textron, Inc. (Bell) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-13

... Airworthiness Directives; Bell Helicopter Textron, Inc. (Bell) Helicopters AGENCY: Federal Aviation...) 76-12- 07 for all Bell Model 204B and certain serial-numbered Model 205A-1 helicopters with a certain... detect a crack in the link segments and, for affected Model 205A-1 helicopters, replacing the chain and...

Investigation of Rotor Performance and Loads of a UH-60A Individual Blade Control System

NASA Technical Reports Server (NTRS)

Yeo, Hyeonsoo; Romander, Ethan A.; Norman, Thomas R.

2011-01-01

Wind tunnel measurements of performance, loads, and vibration of a full-scale UH-60A Black Hawk main rotor with an individual blade control (IBC) system are compared with calculations obtained using the comprehensive helicopter analysis CAMRAD II and a coupled CAMRAD II/OVERFLOW 2 analysis. Measured data show a 5.1% rotor power reduction (8.6% rotor lift to effective-drag ratio increase) using 2/rev IBC actuation with 2.0 amplitude at = 0.4. At the optimum IBC phase for rotor performance, IBC actuator force (pitch link force) decreased, and neither flap nor chord bending moments changed significantly. CAMRAD II predicts the rotor power variations with the IBC phase reasonably well at = 0.35. However, the correlation degrades at = 0.4. Coupled CAMRAD II/OVERFLOW 2 shows excellent correlation with the measured rotor power variations with the IBC phase at both = 0.35 and = 0.4. Maximum reduction of IBC actuator force is better predicted with CAMRAD II, but general trends are better captured with the coupled analysis. The correlation of vibratory hub loads is generally poor by both methods, although the coupled analysis somewhat captures general trends.

Investigation of Rotor Performance and Loads of a UH-60A Individual Blade Control System

NASA Technical Reports Server (NTRS)

Yeo, Hyeonsoo; Romander, Ethan A.; Norman, Thomas R.

2011-01-01

Wind tunnel measurements of performance, loads, and vibration of a full-scale UH-60A Black Hawk main rotor with an individual blade control (IBC) system are compared with calculations obtained using the comprehensive helicopter analysis CAMRAD II and a coupled CAMRAD II/OVERFLOW 2 analysis. Measured data show a 5.1% rotor power reduction (8.6% rotor lift to effective-drag ratio increase) using 2/rev IBC actuation with 2.0. amplitude at u = 0.4. At the optimum IBC phase for rotor performance, IBC actuator force (pitch link force) decreased, and neither flap nor chord bending moments changed significantly. CAMRAD II predicts the rotor power variations with IBC phase reasonably well at u = 0.35. However, the correlation degrades at u = 0.4. Coupled CAMRAD II/OVERFLOW 2 shows excellent correlation with the measured rotor power variations with IBC phase at both u = 0.35 and u = 0.4. Maximum reduction of IBC actuator force is better predicted with CAMRAD II, but general trends are better captured with the coupled analysis. The correlation of vibratory hub loads is generally poor by both methods, although the coupled analysis somewhat captures general trends.

Performance and Loads Correlation of a UH-60A Slowed Rotor at High Advance Ratios

NASA Technical Reports Server (NTRS)

Kottapalli, Sesi B.

2012-01-01

Measured data from the slowed rotor part of the 2010 UH-60A Airloads Rotor test in the NASA Ames 40- by 80- Foot Wind Tunnel are compared with CAMRAD II calculations. The emphasis in this initial study is to correlate overall trends. This analytical effort considers advance ratios from 0.3 to 1.0, with the rotor rotational speed at 40%NR. The rotor performance parameters considered are the thrust coefficient, power coefficient, L/DE, torque, and H-force. The blade loads considered are the half peak-to-peak, mid-span and outboard torsion, flatwise, and chordwise moments, and the pitch link load. For advance ratios . 0.7, the overall trends for the performance and loads (excluding the pitch link load) could be captured, but with substantial overprediction or underprediction. The correlation gradually deteriorates as the advance ratio is increased and for advance ratios . 0.8 there is no correlation. The pitch link load correlation is not good. There is considerable scope for improvement in the prediction of the blade loads. Considering the modeling complexity associated with the unconventional operating condition under consideration, the current predictive ability to capture overall trends is encouraging.

Uh and um revisited: are they interjections for signaling delay?

PubMed

O'Connell, Daniel C; Kowal, Sabine

2005-11-01

Clark and Fox Tree (2002) have presented empirical evidence, based primarily on the London-Lund corpus (LL; Svartvik & Quirk, 1980), that the fillers uh and um are conventional English words that signal a speaker's intention to initiate a minor and a major delay, respectively. We present here empirical analyses of uh and um and of silent pauses (delays) immediately following them in six media interviews of Hillary Clinton. Our evidence indicates that uh and um cannot serve as signals of upcoming delay, let alone signal it differentially: In most cases, both uh and um were not followed by a silent pause, that is, there was no delay at all; the silent pauses that did occur after um were too short to be counted as major delays; finally, the distributions of durations of silent pauses after uh and um were almost entirely overlapping and could therefore not have served as reliable predictors for a listener. The discrepancies between Clark and Fox Tree's findings and ours are largely a consequence of the fact that their LL analyses reflect the perceptions of professional coders, whereas our data were analyzed by means of acoustic measurements with the PRAAT software (www.praat.org). A comparison of our findings with those of O'Connell, Kowal, and Ageneau (2005) did not corroborate the hypothesis of Clark and Fox Tree that uh and um are interjections: Fillers occurred typically in initial, interjections in medial positions; fillers did not constitute an integral turn by themselves, whereas interjections did; fillers never initiated cited speech, whereas interjections did; and fillers did not signal emotion, whereas interjections did. Clark and Fox Tree's analyses were embedded within a theory of ideal delivery that we find inappropriate for the explication of these phenomena.

Calculation of flight vibration levels of the AH-1G helicopter and correlation with existing flight vibration measurements

NASA Technical Reports Server (NTRS)

Sopher, R.; Twomey, W. J.

1990-01-01

NASA-Langley is sponsoring a rotorcraft structural dynamics program with the objective to establish in the U.S. a superior capability to utilize finite element analysis models for calculations to support industrial design of helicopter airframe structures. In the initial phase of the program, teams from the major U.S. manufacturers of helicopter airframes will apply extant finite element analysis methods to calculate loads and vibrations of helicopter airframes, and perform correlations between analysis and measurements. The aforementioned rotorcraft structural dynamics program was given the acronym DAMVIBS (Design Analysis Method for Vibrations). Sikorsky's RDYNE Rotorcraft Dynamics Analysis used for the correlation study, the specifics of the application of RDYNE to the AH-1G, and comparisons of the predictions of the method with flight data for loads and vibrations on the AH-1G are described. RDYNE was able to predict trends of variations of loads and vibrations with airspeed, but in some instances magnitudes differed from measured results by factors of two or three to one. Sensitivities were studied of predictions to rotor inflow modeling, effects of torsional modes, number of blade bending modes, fuselage structural damping, and hub modal content.

Helicopter Drive System on-Condition Maintenance Capability (UH-1/AH-1)

DTIC Science & Technology

1976-07-01

Capability 17 2.2 FACTORS LIMITING THE PERFORMANCE OF THE STUDY . . 18 2.3 ASSUMPTIONS USED IN THE ANALYSIS 20 2.3.1 Assembly Operability 20 2.3.2...DRIVE SYSTEM COMPONENTS AND THEIR EFFECTIVITY 64 2 AIRCRAFT TECHNICAL MANUALS USED DURING THE STUDY 66 3 DRIVE SYSTEM COMPONENTS DA2410 RECORDS...the federal stock number, and current effectivity of these assemblies. The general approach used was to examine the overhaul and acci- dent records

A compilation and analysis of helicopter handling qualities data. Volume 1: Data compilation

NASA Technical Reports Server (NTRS)

Heffley, R. K.; Jewell, W. F.; Lehman, J. M.; Vanwinkle, R. A.

1979-01-01

A collection of basic descriptive data, stability derivatives and transfer functions for six degrees of freedom, quasi-static model is introduced. The data are arranged in a common, compact format for each of the five helicopters represented. The vehicles studied include the BO-105, AH-1h, and the CH53D.

"Uh" and "Um" Revisited: Are They Interjections for Signaling Delay?

ERIC Educational Resources Information Center

O'Connell, Daniel C.; Kowal, Sabine

2005-01-01

Clark and Fox Tree (2002) have presented empirical evidence, based primarily on the London-Lund corpus (LL; Svartvik & Quirk, 1980), that the fillers "uh" and "um" are conventional English words that signal a speaker's intention to initiate a minor and a major delay, respectively. We present here empirical analyses of "uh" and "um" and of silent…

A Model-based Health Monitoring and Diagnostic System for the UH-60 Helicopter. Appendix D

NASA Technical Reports Server (NTRS)

Patterson-Hine, Ann; Hindson, William; Sanderfer, Dwight; Deb, Somnath; Domagala, Chuck

2001-01-01

Model-based reasoning techniques hold much promise in providing comprehensive monitoring and diagnostics capabilities for complex systems. We are exploring the use of one of these techniques, which utilizes multi-signal modeling and the TEAMS-RT real-time diagnostic engine, on the UH-60 Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) flight research aircraft. We focus on the engine and transmission systems, and acquire sensor data across the 1553 bus as well as by direct analog-to-digital conversion from sensors to the QHuMS (Qualtech health and usage monitoring system) computer. The QHuMS computer uses commercially available components and is rack-mounted in the RASCAL facility. A multi-signal model of the transmission and engine subsystems enables studies of system testability and analysis of the degree of fault isolation available with various instrumentation suites. The model and examples of these analyses will be described and the data architectures enumerated. Flight tests of this system will validate the data architecture and provide real-time flight profiles to be further analyzed in the laboratory.

Blade Displacement Measurements of the Full-Scale UH-60A Airloads Rotor

NASA Technical Reports Server (NTRS)

Barrows, Danny A.; Burner, Alpheus W.; Abrego, Anita I.; Olson, Lawrence E.

2011-01-01

Blade displacement measurements were acquired during a wind tunnel test of the full-scale UH-60A Airloads rotor. The test was conducted in the 40- by 80-Foot Wind Tunnel of the National Full-Scale Aerodynamics Complex at NASA Ames Research Center. Multi-camera photogrammetry was used to measure the blade displacements of the four-bladed rotor. These measurements encompass a range of test conditions that include advance ratios from 0.15 to unique slowed-rotor simulations as high as 1.0, thrust coefficient to rotor solidity ratios from 0.01 to 0.13, and rotor shaft angles from -10.0 to 8.0 degrees. The objective of these measurements is to provide a benchmark blade displacement database to be utilized in the development and validation of rotorcraft computational tools. The methodology, system development, measurement techniques, and preliminary sample blade displacement measurements are presented.

Helicopter-based live-line work. Volume 1, Helicopter platform work between phases: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gela, G.

1993-06-01

This report presents experimental data on tests of a configuration consisting of a helicopter between two energized phases (for AC and switching surge) or poles (for DC). The configuration is that related to live-line work from a hovering helicopter. The McDonnell Douglas 500 Series helicopter was used for the tests. All tests were performed with phase-to-phase, or pole-to-pole energization. For AC tests, proper relationship between the phase-to-ground voltages and the phase-to-phase voltage was maintained by energizing the experimental setup from a balanced 3-{phi} AC source. For DC tests, one pole was energized with positive DC voltage to ground, while themore » other pole was energized with negative DC voltage to ground. For switching surge tests, a surge of positive polarity and a specific peak voltage magnitude was applied to one phase while a surge of negative polarity and the same peak voltage Magnitude was simultaneously applied to the other phase, resulting in {alpha} = 0.5 ({alpha} is the ratio between negative and total surge). In the research program, four conditions were investigated, namely helicopter operating versus not operating, and helicopter bonded to one phase or pole versus not bonded. Results from this research show effects of the rotating main rotor blade of the helicopter, effect of the position of the electrically floating helicopter in the phase-to-phase or pole-to-pole gap, effects of the mannequin, importance of the polarity of the DC poles and switching surges, and effects of inclement weather such as rain. The overall conclusion of this research is that the phase-to-phase or pole-to-pole spacings that cause sparkover with the helicopter between phases (poles) were always significantly smaller than the typical spacings on actual existing overhead transmission lines of the corresponding voltage rating.« less

77 FR 23388 - Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-19

... Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters AGENCY: Federal Aviation... are publishing a new airworthiness directive (AD) for Bell Helicopter Textron Canada Limited (Bell..., contact Bell Helicopter Textron Canada Limited, 12,800 Rue de l'Avenir, Mirabel, Quebec J7J1R4, telephone...

Evaluation of ride quality prediction methods for operational military helicopters

NASA Technical Reports Server (NTRS)

Leatherwood, J. D.; Clevenson, S. A.; Hollenbaugh, D. D.

1984-01-01

The results of a simulator study conducted to compare and validate various ride quality prediction methods for use in assessing passenger/crew ride comfort within helicopters are presented. Included are results quantifying 35 helicopter pilots' discomfort responses to helicopter interior noise and vibration typical of routine flights, assessment of various ride quality metrics including the NASA ride comfort model, and examination of possible criteria approaches. Results of the study indicated that crew discomfort results from a complex interaction between vibration and interior noise. Overall measures such as weighted or unweighted root-mean-square acceleration level and A-weighted noise level were not good predictors of discomfort. Accurate prediction required a metric incorporating the interactive effects of both noise and vibration. The best metric for predicting crew comfort to the combined noise and vibration environment was the NASA discomfort index.

DefenseLink Feature: Comrades, Loved Ones Provide Reminders of Memorial

Science.gov Websites

northeast of Baghdad when their UH-60 Black Hawk helicopter was shot down. U.S. Army photo by Sgt. Mary Black Hawk helicopter was shot down near Baghdad on Jan. 20, 2007. Courtesy photo Navy Petty Officer 1st

Rotorcraft In-Flight Simulation Research at NASA Ames Research Center: A Review of the 1980's and plans for the 1990's

NASA Technical Reports Server (NTRS)

Aiken, Edwin W.; Hindson, William S.; Lebacqz, J. Victor; Denery, Dallas G.; Eshow, Michelle M.

1991-01-01

A new flight research vehicle, the Rotorcraft-Aircrew System Concepts Airborne Laboratory (RASCAL), is being developed by the U.S. Army and NASA at ARC. The requirements for this new facility stem from a perception of rotorcraft system technology requirements for the next decade together with operational experience with the Boeing Vertol CH-47B research helicopter that was operated as an in-flight simulator at ARC during the past 10 years. Accordingly, both the principal design features of the CH-47B variable-stability system and the flight-control and cockpit-display programs that were conducted using this aircraft at ARC are reviewed. Another U.S Army helicopter, a Sikorsky UH-60A Black Hawk, was selected as the baseline vehicle for the RASCAL. The research programs that influence the design of the RASCAL are summarized, and the resultant requirements for the RASCAL research system are described. These research programs include investigations of advanced, integrated control concepts for achieving high levels of agility and maneuverability, and guidance technologies, employing computer/sensor-aiding, designed to assist the pilot during low-altitude flight in conditions of limited visibility. The approach to the development of the new facility is presented and selected plans for the preliminary design of the RASCAL are described.

Helicopter Display Improvement Study

DTIC Science & Technology

1975-05-01

PRESSURE INDICATOR 43 TURN A N D SLIP INDICATOR 21 ENGINE AND SDG OIL IN TEMPERATURE INDICATOR 44 COURSE INDICATOR 22 RADIO MAGNETIC COMPASS INDICATOR... compass seemed to present a problem to several H-l series pilots In that It was poorly located and should be moved. Possible locations Included...the UH-lNs standby compass . Both H/L and L/L pilots agreed that internal, white light was the best system currently in use. INDIVIDUAL DISPLAYS

The X-40A immediately after release from its harness suspended from a helicopter 15,000 feet above NASA's Dryden Flight Research Center at Edwards Air Force Base, California, on March 14, 2001

NASA Image and Video Library

2001-03-14

The X-40A immediately after release from its harness suspended from a helicopter 15,000 feet above NASA's Dryden Flight Research Center at Edwards Air Force Base, California, on March 14, 2001. The unpiloted X-40 is a risk-reduction vehicle for the X-37, which is intended to be a reusable space vehicle. NASA's Marshall Space Flight Center in Huntsville, Ala, manages the X-37 project. At Dryden, the X-40A will undergo a series of ground and air tests to reduce possible risks to the larger X-37, including drop tests from a helicopter to check guidance and navigation systems planned for use in the X-37. The X-37 is designed to demonstrate technologies in the orbital and reentry environments for next-generation reusable launch vehicles that will increase both safety and reliability, while reducing launch costs from $10,000 per pound to $1,000 per pound.

US Army Attack Aviation in a Decisive Action Environment: History, Doctrine, and a Need for Doctrinal Refinement

DTIC Science & Technology

2015-05-23

flight. The design used the engine, transmission, and rotor system of the UH-1 design. In doing so, Bell helicopters publicly declared that the Cobra...Public Release; Distribution is Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The attack helicopter airframe and role evolved slowly, over time, to...attack helicopter doctrine, heavily influenced by the Global War on Terror and the 11th Attack Helicopter Regiment’s disastrous deep attack during

The acoustics of a small-scale helicopter rotor in hover

NASA Technical Reports Server (NTRS)

Kitaplioglu, Cahit

1989-01-01

A 2.1 m diameter, 1/6-scale model helicopter main rotor was tested in hover in the test section of the NASA Ames 40- by 80-foot wind tunnel. Performance and noise data on a small-scale rotor at various thrust coefficients and tip Mach numbers were obtained for comparison with existing data on similar full-scale helicopter rotors. These data form part of a data base to permit the estimation of scaling effects on various rotor noise mechanisms. Another objective was to contribute to a data base that will permit the estimation of facility effects on acoustic testing. Acoustic 1/3-octave-band spectra are presented, together with variations of overall acoustic levels with rotor performance, microphone distance, and directivity angle.

A new version of the helicopter aural detection program, ICHIN

NASA Technical Reports Server (NTRS)

Mueller, A. W.; Smith, C. D.; Shepherd, K. P.; Sullivan, B. M.

1986-01-01

NASA Langley Research Center personnel have conducted an evaluation of the helicopter aural detection program I Can Hear It Now (ICHIN version-5). This was accomplished using flight noise data of five helicopters, obtained from a joint NASA and U.S. Army acoustics measurement program. The evaluation consisted of presenting the noise data to a jury of 20 subjects and to the ICHIN-5 program. A comparative study was then made of the detection distances determined by the jury and predicted by ICHIN-5. This report presents the changes made in the ICHIN-5 program as a result of this comparative study. The changes represent current psychoacoustics and propagation knowledge.

Low-noise, high-strength, spiral-bevel gears for helicopter transmissions

NASA Technical Reports Server (NTRS)

Lewicki, David G.; Handschuh, Robert F.; Henry, Zachary S.; Litvin, Faydor L.

1993-01-01

Improvements in spiral-bevel gear design were investigated to support the Army/NASA Advanced Rotorcraft Transmission program. Program objectives were to reduce weight by 25 percent, reduce noise by 10 dB, and increase life to 5000 hr mean-time-between-removal. To help meet these goals, advanced-design spiral-bevel gears were tested in an OH-58D helicopter transmission using the NASA 500-hp Helicopter Transmission Test Stand. Three different gear designs tested included: (1) the current design of the OH-58D transmission except gear material X-53 instead of AISI 9310; (2) a higher-strength design the same as the current but with a full fillet radius to reduce gear tooth bending stress (and thus, weight); and (3) a lower-noise design the same as the high-strength but with modified tooth geometry to reduce transmission error and noise. Noise, vibration, and tooth strain tests were performed and significant gear stress and noise reductions were achieved.

Helicopter Field Testing of NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System fully Integrated with the Morpheus Vertical Test Bed Avionics

NASA Technical Reports Server (NTRS)

Epp, Chirold D.; Robertson, Edward A.; Ruthishauser, David K.

2013-01-01

The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project was chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with real-time terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. This is accomplished with the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN). The NASA plan for the ALHAT technology is to perform the TRL6 closed loop demonstration on the Morpheus Vertical Test Bed (VTB). The first Morpheus vehicle was lost in August of 2012 during free-flight testing at Kennedy Space Center (KSC), so the decision was made to perform a helicopter test of the integrated ALHAT System with the Morpheus avionics over the ALHAT planetary hazard field at KSC. The KSC helicopter tests included flight profiles approximating planetary approaches, with the entire ALHAT system interfaced with all appropriate Morpheus subsystems and operated in real-time. During these helicopter flights, the ALHAT system imaged the simulated lunar terrain constructed in FY2012 to support ALHAT/Morpheus testing at KSC. To the best of our knowledge, this represents the highest fidelity testing of a system of this kind to date. During this helicopter testing, two new Morpheus landers were under construction at the Johnson Space Center to support the objective of an integrated ALHAT/Morpheus free-flight demonstration. This paper provides an overview of this helicopter flight test activity, including results and lessons learned, and also provides an overview of recent integrated testing of ALHAT on the second

Helicopter Field Testing of NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System fully integrated with the Morpheus Vertical Test Bed Avionics

NASA Technical Reports Server (NTRS)

Rutishauser, David; Epp, Chirold; Robertson, Edward

2013-01-01

The Autonomous Landing Hazard Avoidance Technology (ALHAT) Project was chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with real-time terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. This is accomplished with the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN). The NASA plan for the ALHAT technology is to perform the TRL6 closed loop demonstration on the Morpheus Vertical Test Bed (VTB). The first Morpheus vehicle was lost in August of 2012 during free-flight testing at Kennedy Space Center (KSC), so the decision was made to perform a helicopter test of the integrated ALHAT System with the Morpheus avionics over the ALHAT planetary hazard field at KSC. The KSC helicopter tests included flight profiles approximating planetary approaches, with the entire ALHAT system interfaced with all appropriate Morpheus subsystems and operated in real-time. During these helicopter flights, the ALHAT system imaged the simulated lunar terrain constructed in FY2012 to support ALHAT/Morpheus testing at KSC. To the best of our knowledge, this represents the highest fidelity testing of a system of this kind to date. During this helicopter testing, two new Morpheus landers were under construction at the Johnson Space Center to support the objective of an integrated ALHAT/Morpheus free-flight demonstration. This paper provides an overview of this helicopter flight test activity, including results and lessons learned, and also provides an overview of recent integrated testing of ALHAT on the second

Considerations of Methods of Improving Helicopter Efficiency

NASA Technical Reports Server (NTRS)

Dingeldein, Richard C.

1961-01-01

Recent NASA helicopter research indicates that significant improvements in hovering efficiency, up to 7 percent, are available from the use of a special airfoil section formed by combining an NACA 632A015 thickness distribution with an NACA 230 mean line. This airfoil should be considered for flying-crane-type helicopters. Application of standard leading-edge roughness causes a large drop in efficiency; however, the cambered rotor is shown to retain its superiority over a rotor having a symmetrical airfoil when both rotors have leading-edge roughness. A simple analysis of available rotor static-thrust data indicates a greatly reduced effect of compressibility effects on the rotor profile-drag power than predicted from calculations. Preliminary results of an experimental study of helicopter parasite drag indicate the practicability of achieving an equivalent flat-plate parasite-drag area of less than 4 square feet for a rotor-head-pylon-fuselage configuration (landing gear retracted) in the 2,000-pound minimum-flying-weight class. The large drag penalty of a conventional skid-type landing (3.6 square feet) can be reduced by two-thirds by careful design. Clean, fair, and smooth fuselages that tend to have narrow, deep cross sections are shown to have advantages from the standpoint of drag and download. A ferry range of the order of 1,500 miles is indicated to be practicable for the small helicopter considered.

Advanced helicopter cockpit and control configurations for helicopter combat missions

NASA Technical Reports Server (NTRS)

Haworth, Loran A.; Atencio, Adolph, Jr.; Bivens, Courtland; Shively, Robert; Delgado, Daniel

1987-01-01

Two piloted simulations were conducted by the U.S. Army Aeroflightdynamics Directorate to evaluate workload and helicopter-handling qualities requirements for single pilot operation in a combat Nap-of-the-Earth environment. The single-pilot advanced cockpit engineering simulation (SPACES) investigations were performed on the NASA Ames Vertical Motion Simulator, using the Advanced Digital Optical Control System control laws and an advanced concepts glass cockpit. The first simulation (SPACES I) compared single pilot to dual crewmember operation for the same flight tasks to determine differences between dual and single ratings, and to discover which control laws enabled adequate single-pilot helicopter operation. The SPACES II simulation concentrated on single-pilot operations and use of control laws thought to be viable candidates for single pilot operations workload. Measures detected significant differences between single-pilot task segments. Control system configurations were task dependent, demonstrating a need for inflight reconfigurable control system to match the optimal control system with the required task.

Interior noise and vibration measurements on operational military helicopters and comparisons with various ride quality criteria

NASA Technical Reports Server (NTRS)

Clevenson, S. A.; Leatherwood, J. D.; Hollenbaugh, D. D.

1983-01-01

The results of physical measurements of the interior noise and vibration obtained within eight operational military helicopters are presented. The data were extensively analyzed and are presented in the following forms: noise and vibration spectra, overall root-mean-square acceleration levels in three linear axes, peak accelerations at dominant blade passage frequencies, acceleration exceedance data, and overall and ""A'' weighted sound pressure levels. Peak acceleration levels were compared to the ISO 1-hr reduced comfort and fatigue decreased proficiency boundaries and the NASA discomfort criteria. The ""A'' weighted noise levels were compared to the NASA annoyance criteria, and the overall noise spectra were compared to MIL-STD-1294 (""Acoustical Noise Limits in Helicopters''). Specific vibration components at blade passage frequencies for several aircraft exceeded both the ISO reduced comfort boundary and the NASA passenger discomfort criteria. The ""A'' weighted noise levels, corrected for SPH-4 helmet attenuation characteristics, exceeded the NASA annoyance threshold for several aircraft.

Modeling and Simulation of a Helicopter Slung Load Stabilization Device

NASA Technical Reports Server (NTRS)

Cicolani, Luigi S.; Ehlers, George E.

2002-01-01

This paper addresses the problem of simulation and stabilization of the yaw motions of a cargo container slung load. The study configuration is a UH-60 helicopter carrying a 6ft x 6 ft x 8 ft CONEX container. This load is limited to 60 KIAS in operations and flight testing indicates that it starts spinning in hover and that spin rate increases with airspeed. The simulation reproduced the load yaw motions seen in the flight data after augmenting the load model with terms representing unsteady load yaw moment effects acting to reinforce load oscillations, and augmenting the hook model to include yaw resistance at the hook. The use of a vertical fin to stabilize the load is considered. Results indicate that the CONEX airspeed can be extended to 110 kts using a 3x5 ft fin.

Correlation Study of the UH-1B Helicopter Blast Test Results from the DICE-THROW Event

DTIC Science & Technology

1977-10-01

histories using the digital computer for numerical computations and plotting. The data reduction system and procedure are essentially those of...as low as 0 = -0.8 deg) due to a significant move- ment of the remote F/A (fore-and-aft) stick. The time history of this remote control is depicted...I I I 5930 ’ yfv ,y ’N0I1VIA30 MVA oo I idSn 3S0N- 124 -iH9l8 3S0N ■03S/S93a ’-I 󈧣Va MVA J.i3T 3S0N ■ 125 r- 1 1 r r 1 ■ 1

FAA Vertical Flight Bibliography, 1962 - 1994

DTIC Science & Technology

1994-08-01

high altitude conditions. A UH-1H aircraft will be used. This project is similar to the work documented in FAA/CT-TN87/40 "Heliport Approach and... work . TITLE: TEST PLAN FOR HELICOPTER VISUAL SEGMENT APPROACH LIGHTING SYSTEM (HALS) REPORT #: FAA/CT-TN88/19 NTIS: N/ A DATE: November 1988 AUTHORS...Hiering, Robert H. Ahlers) (NTIS: N/ A ) RD-64-4 State-of-the-Art Survey for Minimum Approach , Landing and Takeoff Intervals as Dictated by Wakes

Helicopter Acoustic Flight Test with Altitude Variation and Maneuvers

NASA Technical Reports Server (NTRS)

Watts, Michael E.; Greenwood, Eric; Sim, Ben; Stephenson, James; Smith, Charles D.

2016-01-01

A cooperative flight test campaign between NASA and the U.S. Army was performed from September 2014 to February 2015. The purposes of the testing were to: investigate the effects of altitude variation on noise generation, investigate the effects of gross weight variation on noise generation, establish the statistical variability in acoustic flight testing of helicopters, and characterize the effects of transient maneuvers on radiated noise for a medium-lift utility helicopter. This test was performed at three test sites (0, 4000, and 7000 feet above mean sea level) with two aircraft (AS350 SD1 and EH-60L) tested at each site. This report provides an overview of the test, documents the data acquired and describes the formats of the stored data.

Helicopter Fatigue Life Assessment

DTIC Science & Technology

1981-03-01

is made to bring together alternative statistical opinions. 1. INTRODUCTION In almost arn paper on helicopter fatigue (references 1-15) a diagram is...of fatigue life calculations. In the excercise of the A.H.S., mentioned in the introduction the ratios of fatljue life, based on a cycle counting...monitoring. I INTRODUCTION The requirements for the design of structures of United Kingdom Military aeroplanes against fatigue are contained in Aviation

Evaluation of ride quality prediction methods for helicopter interior noise and vibration environments

NASA Technical Reports Server (NTRS)

Leatherwood, J. D.; Clevenson, S. A.; Hollenbaugh, D. D.

1984-01-01

The results of a simulator study conducted to compare and validate various ride quality prediction methods for use in assessing passenger/crew ride comfort within helicopters are presented. Included are results quantifying 35 helicopter pilots discomfort responses to helicopter interior noise and vibration typical of routine flights, assessment of various ride quality metrics including the NASA ride comfort model, and examination of possible criteria approaches. Results of the study indicated that crew discomfort results from a complex interaction between vibration and interior noise. Overall measures such as weighted or unweighted root-mean-square acceleration level and A-weighted noise level were not good predictors of discomfort. Accurate prediction required a metric incorporating the interactive effects of both noise and vibration. The best metric for predicting crew comfort to the combined noise and vibration environment was the NASA discomfort index.

Unsteady flow and dynamic response analyses for helicopter rotor blades

NASA Technical Reports Server (NTRS)

Bratanow, T.

1979-01-01

Research is presented on helicopter rotor blade vibration and on two and three dimensional analyses of unsteady incompressible viscous flow past oscillating helicopter rotor blades. A summary is presented of the two international research collaborations which resulted from the NASA project: the collaboration under the auspices of NATO between the University of Wisconsin-Milwaukee, University of Brussels, Belgium and the Aerodynamics Research Establishment in Goettingen, West Germany, and the collaboration under the auspices of the National Science Foundation between UWM and the University of Hamburg and the Ship Research Establishment in Hamburg, West Germany. A summary is given of the benefits from the NASA project to UWM, the College of Engineering and Applied Science, and the participants on the project.

Quantum 1/F Noise in Solid State Double Devices, in Particular Hg(1-x) CdxTe Diodes.

DTIC Science & Technology

1986-05-22

1 / f noise , diffusion noise , recombination noise , Hooge formula, Hooge parameter, coherent and...The data will be discussed and interpreted in subsequent sections. f 1 . The Hooge equation and quantum 1 / f noise (A. van der Ziel) According to Hooge [ 1 ...the relative current 1 / f noise of a semiconductor resistor may be written as SI( f ) uH 12 N where uH is the Hooge

76 FR 12274 - Special Conditions: Bell Helicopter Textron Canada Limited Model 206B and 206L Series Helicopters...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-07

..., Type Certificate Number H2SW. This AP/SAS performs non- critical control functions, since this model... helicopters. These model helicopters will have novel or unusual design features when modified by installing..., Aviation Safety Engineer, FAA, Rotorcraft Directorate, Regulations and Policy Group (ASW-111), 2601 Meacham...

Development and evaluation of a helicopter-borne water-quality monitoring system

NASA Technical Reports Server (NTRS)

Wallace, J. W.; Jordan, R. A.; Flynn, J.; Thomas, R. W.

1978-01-01

A small, helicopter-borne water-quality monitoring package is being developed by the NASA/EPA using a combination of basic in situ water quality sensors and physical sample collector technology. The package is a lightweight system which can be carried and operated by one person as a passenger in a small helicopter typically available by rental at commercial airports. Real-time measurements are made by suspending the water quality monitoring package with a cable from the hovering helicopter. Designed primarily for use in rapidly assessing hazardous material spills in inland and coastal zone water bodies, the system can survey as many as 20 data stations up to 1.5 kilometers apart in 1 hour. The system provides several channels of sensor data and allows for the addition of future sensors. The system will also collect samples from selected sites with sample collection on command. An EPA Spill Response Team member can easily transport, deploy, and operate the water quality monitoring package to determine the distribution, movement, and concentration of the spilled material in the water body.

An investigation of helicopter dynamic coupling using an analytical model

NASA Technical Reports Server (NTRS)

Keller, Jeffrey D.

1995-01-01

Many attempts have been made in recent years to predict the off-axis response of a helicopter to control inputs, and most have had little success. Since physical insight is limited by the complexity of numerical simulation models, this paper examines the off-axis response problem using an analytical model, with the goal of understanding the mechanics of the coupling. A new induced velocity model is extended to include the effects of wake distortion from pitch rate. It is shown that the inclusion of these results in a significant change in the lateral flap response to a steady pitch rate. The proposed inflow model is coupled with the full rotor/body dynamics, and comparisons are made between the model and flight test data for a UH-60 in hover. Results show that inclusion of induced velocity variations due to shaft rate improves correlation in the pitch response to lateral cycle inputs.

Iceproofing Helicopters

NASA Technical Reports Server (NTRS)

1977-01-01

NASA aircraft-icing research has been applied to expand the utility of the big flying-crane helicopter built by the Sikorsky Aircraft Division of United Technologies in Stratford, Conn. Sikorsky wanted to adapt the Skycrane, used in both military and commercial service, to lift heavy external loads in areas where icing conditions occur; ice build-up around the engine air inlets caused the major problem. NASA-Lewis has a special wind tunnel for injecting super cooled water droplets into the wind thereby simulating a natural icing cloud and observing how ice builds up on various shaped surfaces. From Lewis, Sikorsky engineers obtained information which optimized the design of the inlet anti-ice system. The resulting design proved to be an effective anti-icing modification for the flying crane. Sikorsky is also using additional Lewis Icing Research Tunnel data in its development of a new VTOL (Vertical Take-Off and Landing) aircraft.

The 3600 hp split-torque helicopter transmission

NASA Technical Reports Server (NTRS)

White, G.

1985-01-01

Final design details of a helicopter transmission that is powered by GE twin T 700 engines each rated at 1800 hp are presented. It is demonstrated that in comparison with conventional helicopter transmission arrangements the split torque design offers: weight reduction of 15%; reduction in drive train losses of 9%; and improved reliability resulting from redundant drive paths between the two engines and the main shaft. The transmission fits within the NASA LeRC 3000 hp Test Stand and accepts the existing positions for engine inputs, main shaft, connecting drive shafts, and the cradle attachment points. One necessary change to the test stand involved gear trains of different ratio in the tail drive gearbox. Progressive uprating of engine input power from 3600 to 4500 hp twin engine rating is allowed for in the design. In this way the test transmission will provide a base for several years of analytical, research, and component development effort targeted at improving the performance and reliability of helicopter transmission.

Helicopter theory

NASA Technical Reports Server (NTRS)

Johnson, W.

1980-01-01

A comprehensive presentation is made of the engineering analysis methods used in the design, development and evaluation of helicopters. After an introduction covering the fundamentals of helicopter rotors, configuration and operation, rotary wing history, and the analytical notation used in the text, the following topics are discussed: (1) vertical flight, including momentum, blade element and vortex theories, induced power, vertical drag and ground effect; (2) forward flight, including in addition to momentum and vortex theory for this mode such phenomena as rotor flapping and its higher harmonics, tip loss and root cutout, compressibility and pitch-flap coupling; (3) hover and forward flight performance assessment; (4) helicopter rotor design; (5) rotary wing aerodynamics; (6) rotary wing structural dynamics, including flutter, flap-lag dynamics ground resonance and vibration and loads; (7) helicopter aeroelasticity; (8) stability and control (flying qualities); (9) stall; and (10) noise.

Assessment of Comprehensive Analysis Calculation of Airloads on Helicopter Rotors

NASA Technical Reports Server (NTRS)

Yeo, Hyeonsoo; Johnson, Wayne

2004-01-01

Blade section normal force and pitching moment were investigated for six rotors operating at transition and high speeds: H-34 in flight and wind tunnel, SA 330 (research Puma), SA 349/2, UH-60A full-scale and BO-105 model (HART-I). The measured data from flight and wind tunnel tests were compared with calculations obtained using the comprehensive analysis CAMRAD II. The calculations were made using two free wake models: rolled-up and multiple-trailer with consolidation models. At transition speed, there is fair to good agreement for the blade section normal force between the test data and analysis for the H-34, research Puma, and SA 349/2 with the rolled-up wake. The calculated airloads differ significantly from the measurements for the UH-60A and BO-105. Better correlation is obtained for the UH-60A and BO-105 by using the multiple-trailer with consolidation wake model. In the high speed condition, the analysis shows generally good agreement with the research Puma flight data in both magnitude and phase. However, poor agreement is obtained for the other rotors examined. The analysis shows that the aerodynamic tip design (chord length and quarter chord location) of the Puma has an important influence on the phase correlation.

Revolutionary Concepts for Helicopter Noise Reduction: SILENT Program

NASA Technical Reports Server (NTRS)

Edwards, Bryan; Cox, Charles; Booth, Earl R., Jr. (Technical Monitor)

2002-01-01

As part of a NASA initiative to reduce helicopter main rotor noise, a Phase 1 study has been performed of candidate noise reduction concepts. Both conventional and novel design technologies have been analyzed that reduce the community impact of helicopter operations. In this study the noise reduction potential and design implications are assessed for conventional means of noise reduction, e.g., tip speed reduction, tip shapes and airfoil tailoring, and for two innovative design concepts: modulated blade spacing and x-force control. Main rotor designs that incorporate modulated blade spacing are shown to have reduced peak noise levels in most flight operations. X-force control alters the helicopter's force balance whereby the miss distance between main rotor blades and shed vortices can be controlled. This control provides a high potential to mitigate BVI noise radiation. Each concept is evaluated using best practice design and analysis methods, achieving the study's aim to significantly reduce noise with minimal performance degradation and no vibration increase. It is concluded that a SILENT main rotor design, incorporating the modulated blade spacing concept, offers significantly reduced noise levels and the potential of a breakthrough in how a helicopter's sound is perceived and judged. The SILENT rotor represents a definite advancement in the state-of-the-art and is selected as the design concept for demonstration in Phase 2. A Phase 2 Implementation Plan is developed for whirl cage and wind tunnel evaluations of a scaled model SILENT rotor.

Genome-wide increase in histone H2A ubiquitylation in a mouse model of Huntington's disease.

PubMed

McFarland, Karen N; Das, Sudeshna; Sun, Ting Ting; Leyfer, Dmitri; Kim, Mee-Ohk; Xia, Eva; Sangrey, Gavin R; Kuhn, Alexandre; Luthi-Carter, Ruth; Clark, Timothy W; Sadri-Vakili, Ghazaleh; Cha, Jang-Ho J

2013-01-01

Huntington's disease (HD) is a neurodegenerative disorder with selective vulnerability of striatal neurons and involves extensive transcriptional dysregulation early in the disease process. Previous work in cell and mouse models has shown that histone modifications are altered in HD. Specifically, monoubiquitylated histone H2A (uH2A) is present at the promoters of downregulated genes which led to the hypothesis that uH2A plays a role in transcriptional silencing in HD. To broaden our view of uH2A function in transcription in HD, we examined genome-wide binding sites of uH2A in 12-week old striatal tissue from R6/2 transgenic HD mouse model. We used chromatin immunoprecipitation followed by genomic promoter microarray hybridization (ChIP-chip) and then interrogated how these binding sites correlate with transcribed genes. Our analysis reveals that, while uH2A levels are globally increased at the genome in the transgenic (TG) striatum, uH2A localization at a gene did not strongly correlate with the absence of its transcript. Furthermore, analysis of differential ubiquitylation in wild-type (WT) and TG striata did not reveal the expected enrichment of uH2A at genes with decreased expression in the TG striatum. This first description of genome-wide localization of uH2A in an HD model reveals that monoubiquitylation of histone H2A may not function at the level of the individual gene but may rather influence transcription through global chromatin structure.

Two-dimensional aerodynamic characteristics of several polygon-shaped cross-sectional models applicable to helicopter fuselages

NASA Technical Reports Server (NTRS)

Kelley, Henry L.; Crowell, Cynthia A.; Wilson, John C.

1992-01-01

A wind-tunnel investigation was conducted to determine 2-D aerodynamic characteristics of nine polygon-shaped models applicable to helicopter fuselages. The models varied from 1/2 to 1/5 scale and were nominally triangular, diamond, and rectangular in shape. Side force and normal force were obtained at increments of angle of flow incidence from -45 to 90 degrees. The data were compared with results from a baseline UH-60 tail-boom cross-section model. The results indicate that the overall shapes of the plots of normal force and side force were similar to the characteristic shape of the baseline data; however, there were important differences in magnitude. At a flow incidence of 0 degrees, larger values of normal force for the polygon models indicate an increase in fuselage down load of 1 to 2.5 percent of main-rotor thrust compared with the baseline value. Also, potential was indicated among some of the configurations to produce high fuselage side forces and yawing moments compared with the baseline model.

Helicopter noise regulations: An industry perspective

NASA Technical Reports Server (NTRS)

Wagner, R. A.

1978-01-01

A review of helicopter noise measurement programs and noise reduction/economic studies of FAA is given along with a critique of a study which addresses the economic impact of noise reduction on helicopter noise. Modification of several helicopters to reduce noise and demonstrate the economic impact of the application of the current state-of-the-art technology is discussed. Specific helicopters described include Boeing Vertol 347 Helicopter, Hughes OH-6 Helicopter, and Hughes 269C Helicopter. Other topics covered include: (1) noise trends and possible noise limits; (2) accuracy of helicopter noise prediction techniques; (3) limited change possibilities of derivatives; and (4) rotor impulsive noise. The unique operational capabilities of helicopters and the implications relative to noise regulations and certification are discussed.

NASA and Canadian Snowbirds Aircrafts

NASA Image and Video Library

2018-05-09

Several types of aircraft are on the tarmac at the Shuttle Landing Facility (SLF) at NASA's Kennedy Space in Florida. From left, are two Canadian Forces Snowbird CF-18 jets, a NASA Huey helicopter, and two NASA T-38 trainer aircraft. The Canadian Forces Snowbirds performed aerial maneuvers over Kennedy and Cape Canaveral Air Force Station during a practice flight on May 9, 2018, between their scheduled air shows.

The many faces of ubiquitinated histone H2A: insights from the DUBs

PubMed Central

Vissers, Joseph HA; Nicassio, Francesco; van Lohuizen, Maarten; Di Fiore, Pier Paolo; Citterio, Elisabetta

2008-01-01

Monoubiquitination of H2A is a major histone modification in mammalian cells. Understanding how monoubiquitinated H2A (uH2A) regulates DNA-based processes in the context of chromatin is a challenging question. Work in the past years linked uH2A to transcriptional repression by the Polycomb group proteins of developmental regulators. Recently, a number of mammalian deubiquitinating enzymes (DUBs) that catalyze the removal of ubiquitin from H2A have been discovered. These studies provide convincing evidence that H2A deubiquitination is connected with gene activation. In addition, uH2A regulatory enzymes have crucial roles in the cellular response to DNA damage and in cell cycle progression. In this review we will discuss new insights into uH2A biology, with emphasis on the H2A DUBs. PMID:18430235

Operator’s Manual for UH-60A Helicopter, UH-60L Helicopter, EH-60A Helicopter

DTIC Science & Technology

1996-10-31

electrolyte is harmful to the skin and clothing. If potassium hydroxide is spilled on clothing or other material, wash immediately with clean water . If spilled...on personnel, immediately flush the affected area with clean water . Continue washing until medical assistance arrives. Neutralize any spilled...electrolyte by thoroughly flushing contacted area with water . CARBON MONOXIDE When smoke, suspected carbon monoxide fumes, or symptoms of anoxia exist, the

Hover and forward flight acoustics and performance of a small-scale helicopter rotor system

NASA Technical Reports Server (NTRS)

Kitaplioglu, C.; Shinoda, P.

1985-01-01

A 2.1-m diam., 1/6-scale model helicopter main rotor was tested in hover in the test section of the NASA Ames 40- by 80- Foot Wind Tunnel. Subsequently, it was tested in forward flight in the Ames 7- by 10-Foot Wind Tunnel. The primary objective of the tests was to obtain performance and noise data on a small-scale rotor at various thrust coefficients, tip Mach numbers, and, in the later case, various advance ratios, for comparisons with similar existing data on full-scale helicopter rotors. This comparison yielded a preliminary evaluation of the scaling of helicopter rotor performance and acoustic radiation in hover and in forward flight. Correlation between model-scale and full-scale performance and acoustics was quite good in hover. In forward flight, however, there were significant differences in both performance and acoustic characteristics. A secondary objective was to contribute to a data base that will permit the estimation of facility effects on acoustic testing.

Maneuver Acoustic Flight Test of the Bell 430 Helicopter

NASA Technical Reports Server (NTRS)

Watts, Michael E.; Snider, Royce; Greenwood, Eric; Baden, Joel

2012-01-01

A cooperative flight test by NASA, Bell Helicopter and the U.S. Army to characterize the steady state acoustics and measure the maneuver noise of a Bell Helicopter 430 aircraft was accomplished. The test occurred during June/July, 2011 at Eglin Air Force Base, Florida. This test gathered a total of 410 data points over 10 test days and compiled an extensive data base of dynamic maneuver measurements. Three microphone configurations with up to 31 microphones in each configuration were used to acquire acoustic data. Aircraft data included DGPS, aircraft state and rotor state information. This paper provides an overview of the test.

Helicopter Flight Test of a Compact, Real-Time 3-D Flash Lidar for Imaging Hazardous Terrain During Planetary Landing

NASA Technical Reports Server (NTRS)

Roback, VIncent E.; Amzajerdian, Farzin; Brewster, Paul F.; Barnes, Bruce W.; Kempton, Kevin S.; Reisse, Robert A.; Bulyshev, Alexander E.

2013-01-01

A second generation, compact, real-time, air-cooled 3-D imaging Flash Lidar sensor system, developed from a number of cutting-edge components from industry and NASA, is lab characterized and helicopter flight tested under the Autonomous Precision Landing and Hazard Detection and Avoidance Technology (ALHAT) project. The ALHAT project is seeking to develop a guidance, navigation, and control (GN&C) and sensing system based on lidar technology capable of enabling safe, precise crewed or robotic landings in challenging terrain on planetary bodies under any ambient lighting conditions. The Flash Lidar incorporates a 3-D imaging video camera based on Indium-Gallium-Arsenide Avalanche Photo Diode and novel micro-electronic technology for a 128 x 128 pixel array operating at a video rate of 20 Hz, a high pulse-energy 1.06 µm Neodymium-doped: Yttrium Aluminum Garnet (Nd:YAG) laser, a remote laser safety termination system, high performance transmitter and receiver optics with one and five degrees field-of-view (FOV), enhanced onboard thermal control, as well as a compact and self-contained suite of support electronics housed in a single box and built around a PC-104 architecture to enable autonomous operations. The Flash Lidar was developed and then characterized at two NASA-Langley Research Center (LaRC) outdoor laser test range facilities both statically and dynamically, integrated with other ALHAT GN&C subsystems from partner organizations, and installed onto a Bell UH-1H Iroquois "Huey" helicopter at LaRC. The integrated system was flight tested at the NASA-Kennedy Space Center (KSC) on simulated lunar approach to a custom hazard field consisting of rocks, craters, hazardous slopes, and safe-sites near the Shuttle Landing Facility runway starting at slant ranges of 750 m. In order to evaluate different methods of achieving hazard detection, the lidar, in conjunction with the ALHAT hazard detection and GN&C system, operates in both a narrow 1deg FOV raster

Flight-test evaluation of civil helicopter terminal approach operations using differential GPS

NASA Technical Reports Server (NTRS)

Edwards, F. G.; Hegarty, D. M.

1989-01-01

A civil code differential Global Positioning System (DGPS) has been developed and flight-tested by the NASA Ames Research Center. The system was used to evaluate the performance of the DGPS for support of helicopter terminal approach operations. The airborne component of the DGPS was installed in a NASA helicopter. The ground-reference component was installed in a mobile van and equipped with a real-time VHF telemetry data link to transmit correction information to the aircraft system. An extensive series of tests was conducted to evaluate the performance of the system for several different configurations of the airborne navigation filter. This paper will describe the systems, the results of the flight tests, and the results of the posttest analysis.

The effect of operations on the ground noise footprints associated with a large multibladed, nonbanging helicopter

NASA Technical Reports Server (NTRS)

Hilton, D. A.; Henderson, H. R.; Maglieri, D. J.; Bigler, W. B., II

1978-01-01

In order to expand the data base of helicopter external noise characteristics, a flyover noise measurement program was conducted utilizing the NASA Civil Helicopter Research Aircraft. The remotely operated multiple array acoustics range (ROMAAR) and a 2560-m linear microphone array were utilized for the purpose of documenting the noise characteristics of the test helicopter during flyby and landing operations. By utilizing both ROMAAR concept and the linear array, the data necessary to plot the ground noise footprints and noise radiation patterns were obtained. Examples of the measured noise signature of the test helicopter, the ground noise footprint or contours, and the directivity patterns measured during level flyby and landing operations of a large, multibladed, nonbanging helicopter, the CH-53, are presented.

Design and Flight Evaluation of an Integrated Navigation and Near-Terrain Helicopter Guidance System for Nighttime and Adverse Weather Operations

DOT National Transportation Integrated Search

1994-08-01

NASA and the U.S. Army have designed, developed, and flight evaluated a : Computer Aiding for Low-Altitude Helicopter Flight (CALAHF) guidance system. : This system provides guidance to the pilot for near-terrain covert helicopter : operations. It au...

Preliminary study of the pilot's workload during emergency procedures in helicopters air operations.

PubMed

Bezerra, Flávio G V; Ribeiro, Selma L O

2012-01-01

Military air operations and law enforcement operations in helicopters are examples of activities that require high performance of the operator. This article aimed at presenting a preliminary analysis of data obtained in the initial study in order to validate the instruments and the research protocol that focuses on the analysis of the workload imposed on helicopter pilots in emergency situations. The research was conducted in an environment of real flight training and used the NASA-TLX Scale to assess the workload and an interview guide to obtain reports on the main tasks performed. Preliminary data obtained is related to the participation of 10 (ten) volunteer pilots with experience in different types of helicopters. Four scenarios involving helicopter emergency procedures of HB-350 "Squirrel" were outlined. For this article, the analysis used only the data regarding the Physical and Mental Demands of the NASA-TLX Scale. Preliminarily, the results indicate that the "time pressure" as a factor contributing to increase mental requirement in emergency situations in flight, and that this increase was reflected in the request of mental processes such as: identification of the breakdown, attention and monitoring parameters. Future steps include extending the sample and adding physiological tools to better understand the effects of these types of emergencies on pilot performance and flight safety.

77 FR 12991 - Airworthiness Directives; Robinson Helicopter Company Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-05

... Airworthiness Directives; Robinson Helicopter Company Helicopters AGENCY: Federal Aviation Administration (FAA...) that was published in the Federal Register. That AD applies to Robinson Helicopter Company (Robinson...

78 FR 1730 - Airworthiness Directives; Bell Helicopter Textron Inc. Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-09

... Helicopter Textron Inc. (BHTI) Model 205A, 205A-1, and 205B helicopters with certain starter/generator power... that may lead to a fire in the starter/generator, smoke in the cockpit that reduces visibility, and... Office, M-30, West Building Ground Floor, Room W12- 140, 1200 New Jersey Avenue SE., Washington, DC 20590...

Helicopter crashworthiness research program

NASA Technical Reports Server (NTRS)

Farley, Gary L.; Boitnott, Richard L.; Carden, Huey D.

1988-01-01

Results are presented from the U.S. Army-Aerostructures Directorate/NASA-Langley Research Center joint research program on helicopter crashworthiness. Through the on-going research program an in-depth understanding was developed on the cause/effect relationships between material and architectural variables and the energy-absorption capability of composite material and structure. Composite materials were found to be efficient energy absorbers. Graphite/epoxy subfloor structures were more efficient energy absorbers than comparable structures fabricated from Kevlar or aluminum. An accurate method predicting the energy-absorption capability of beams was developed.

The Integration of all Fleet Air Arm Helicopters into Joint Helicopter Command

DTIC Science & Technology

2008-04-04

Defence Comptroller and Auditor General, Helicopter Logistics HC 840 Session 2001 – 2002, 23 May 2002, 1. 4 The Army currently operate Apache AH1...and Auditor report into MOD 5 Major General Gary Coward discussion with Jane’s correspondent, Tim...janes.com.ezproxy6.ndu.edu, 1. 6 Ministry of Defence Comptroller and Auditor General: Battlefield Helicopters HC 486 Session 2003 – 2004, 7 April 2004

An anthropometric analysis of Korean male helicopter pilots for helicopter cockpit design.

PubMed

Lee, Wonsup; Jung, Kihyo; Jeong, Jeongrim; Park, Jangwoon; Cho, Jayoung; Kim, Heeeun; Park, Seikwon; You, Heecheon

2013-01-01

This study measured 21 anthropometric dimensions (ADs) of 94 Korean male helicopter pilots in their 20s to 40s and compared them with corresponding measurements of Korean male civilians and the US Army male personnel. The ADs and the sample size of the anthropometric survey were determined by a four-step process: (1) selection of ADs related to helicopter cockpit design, (2) evaluation of the importance of each AD, (3) calculation of required sample sizes for selected precision levels and (4) determination of an appropriate sample size by considering both the AD importance evaluation results and the sample size requirements. The anthropometric comparison reveals that the Korean helicopter pilots are larger (ratio of means = 1.01-1.08) and less dispersed (ratio of standard deviations = 0.71-0.93) than the Korean male civilians and that they are shorter in stature (0.99), have shorter upper limbs (0.89-0.96) and lower limbs (0.93-0.97), but are taller on sitting height, sitting eye height and acromial height (1.01-1.03), and less dispersed (0.68-0.97) than the US Army personnel. The anthropometric characteristics of Korean male helicopter pilots were compared with those of Korean male civilians and US Army male personnel. The sample size determination process and the anthropometric comparison results presented in this study are useful to design an anthropometric survey and a helicopter cockpit layout, respectively.

Aircraft Transparency Failure and Logistical Cost Analysis. Volume I. Program Summary

DTIC Science & Technology

1978-12-01

Hours liv LIST OF ABBREVIATIONS (Continued) SFMC Field Maintenance Cost FMEA Failure Modes and Effect Analysis SFMS Field Maintenance Squadron FSN...3, CH-53, AND UH -1 Figure 3. Study Aircraft 10 I. 1. WINDSHIELDS 2. CANOPIES 3. WINDOWS INTERACTIVE SUPPORT SYSTEMS 1. ANTI-ICING 2. DEFOGGING 3...52,947 13,761 UH /TH-1F, 1P 73,431 73,640 Total helicopters 339,690 113,492 2.99 Bombers B-S2G 138,348 64,431 B-S2P 93,000 36,936 B-57 34,527 19,552

New fire-fighting water bucket is lifted by helicopter

NASA Technical Reports Server (NTRS)

2000-01-01

A NASA helicopter lifts a high-impact-resistant flexible plastic bucket that will be used for fire protection on property and buildings at Kennedy Space Center. Known as the 'Bambi' bucket, the 324-gallon container will also support the Fish and Wildlife Service for controlled burns plus any wild fires in the area.

77 FR 30232 - Airworthiness Directives; Bell Helicopter Textron Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

...-0530; Directorate Identifier 2011-SW-075-AD] RIN 2120-AA64 Airworthiness Directives; Bell Helicopter Textron Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). SUMMARY: We propose to adopt a new airworthiness directive (AD) for Bell Helicopter...

Control of a human-powered helicopter in hover

NASA Technical Reports Server (NTRS)

Totah, Joseph J.; Patterson, William

1988-01-01

The study of a control system for the Da Vinci 2 human-powered helicopter in hovering flight is documented. This helicopter has two very large, slowly rotating rotor blades and is considered to be unstable in hover. The control system is designed to introduce stability in hover by maintaining level rotors through the use of rotor tip mounted control surfaces. A five degree of freedom kinematic model was developed to study this control system and is documented. Results of this study show that the unaugmented configuration is unstable due to the large Lock Number, and the augmented configuration is stable. The role of NASA in this study included the development and analysis of the kinematic model and control laws. Both analytical and numerical techniques were used.

[Rescue helicopters in secondary missions].

PubMed

Gorgass, B; Frey, G

1977-11-03

During the last five years, we have had to fly 560 primary and 1150 secondary missions with the rescue helicopter of the Ulm Rescue Centre. This relationship of approximately 1 : 2 is distinctly different from the numbers obtained in other helicopter bases. The geographical location and structure of the hospitals within range of the Ulm rescue helicopter account for the large proportion of urgent secondary missions. The evaluation of these secondary missions concurs with the ADAC statistics and shows that the quick transport of the emergency doctor to the scene of the emergency, is only one component in the functions of the rescue helicopter. During primary and secondary missions, the ability to transport emergency patients to the nearest qualified hospital by helicopter, which is a mobile intensive care unit, is of equal importance. In the future, rescue helicopters will have to take these requirements into account by providing the necessary equipment and more especially, by providing sufficient space to carry out emergency diagnostic and therapeutic treatment.

Specialists Meeting on Helicopter Design Mission Load Spectra

DTIC Science & Technology

1976-08-01

partement Scientifique AEROSPATIAI*E - B.P n0 13 13 722 -AINN 1I INTRODUCTION Si 1e princips g~ndral de d~tarmination des dur~ea de vie des pibcea d’h...reprdsentatives de l’utilisation h 6valuer un certain nombro do jauges.extensom~triques. Coa jauges , placgos sur chacun des 4ldmonte critiquos au point do Vuo...sensitivity. 1. INTRODUCTION The design of the fatigue critical components of a helicopter, which are mainly the blades, the hub, and the drive system

SCAT Classifications of 5 Supernovae with the UH88/SNIFS

NASA Astrophysics Data System (ADS)

Tucker, Michael A.; Huber, Mark; Shappee, Benjamin J.; Dong, Subo; Bose, S.; Chen, Ping

2018-03-01

We present the first classifications from the newly formed Spectral Classification of Astronomical Transients (SCAT) survey. SCAT is a transient identification survey utilizing the SuperNova Integral Field Spectrograph (SNIFS) on the University of Hawaii (UH) 88-inch telescope.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: Boeing Helicopters airframe finite element modeling

NASA Technical Reports Server (NTRS)

Gabel, R.; Lang, P.; Reed, D.

1993-01-01

Mathematical models based on the finite element method of structural analysis, as embodied in the NASTRAN computer code, are routinely used by the helicopter industry to calculate airframe static internal loads used for sizing structural members. Historically, less reliance has been placed on the vibration predictions based on these models. Beginning in the early 1980's NASA's Langley Research Center initiated an industry wide program with the objective of engendering the needed trust in vibration predictions using these models and establishing a body of modeling guides which would enable confident future prediction of airframe vibration as part of the regular design process. Emphasis in this paper is placed on the successful modeling of the Army/Boeing CH-47D which showed reasonable correlation with test data. A principal finding indicates that improved dynamic analysis requires greater attention to detail and perhaps a finer mesh, especially the mass distribution, than the usual stress model. Post program modeling efforts show improved correlation placing key modal frequencies in the b/rev range with 4 percent of the test frequencies.

Numerical simulation of helicopter engine plume in forward flight

NASA Technical Reports Server (NTRS)

Dimanlig, Arsenio C. B.; Vandam, Cornelis P.; Duque, Earl P. N.

1994-01-01

Flowfields around helicopters contain complex flow features such as large separated flow regions, vortices, shear layers, blown and suction surfaces and an inherently unsteady flow imposed by the rotor system. Another complicated feature of helicopters is their infrared signature. Typically, the aircraft's exhaust plume interacts with the rotor downwash, the fuselage's complicated flowfield, and the fuselage itself giving each aircraft a unique IR signature at given flight conditions. The goal of this project was to compute the flow about a realistic helicopter fuselage including the interaction of the engine air intakes and exhaust plume. The computations solve the Think-Layer Navier Stokes equations using overset type grids and in particular use the OVERFLOW code by Buning of NASA Ames. During this three month effort, an existing grid system of the Comanche Helicopter was to be modified to include the engine inlet and the hot engine exhaust. The engine exhaust was to be modeled as hot air exhaust. However, considerable changes in the fuselage geometry required a complete regriding of the surface and volume grids. The engine plume computations have been delayed to future efforts. The results of the current work consists of a complete regeneration of the surface and volume grids of the most recent Comanche fuselage along with a flowfield computation.

Comparison of Predicted and Measured Temperatures of UH-60A Helicopter Transmission

DTIC Science & Technology

1989-04-01

heairingt S StnilIea 2 24 2 2 Upper Unm shatt hearinL 24) 6,5 _j0 I Cnhirni.t betel itear 34432 C 20 40 50 811 1C0 IS ljmc~r tin that hearinut 441,k Irot...torque. percent of full rated VI Planet hearint (undler ring) 246.2 (a) ()l Percent of full rated speed) II Betel gear 73W61 (hI 75 Percent of’ full

Identification and proposed control of helicopter transmission noise at the source

NASA Technical Reports Server (NTRS)

Coy, John J.; Handschuh, Robert F.; Lewicki, David G.; Huff, Ronald G.; Krejsa, Eugene A.; Karchmer, Allan M.; Coy, John J.

1988-01-01

Helicopter cabin interiors require noise treatment which is expensive and adds weight. The gears inside the main power transmission are major sources of cabin noise. Work conducted by the NASA Lewis Research Center in measuring cabin interior noise and in relating the noise spectrum to the gear vibration of the Army OH-58 helicopter is described. Flight test data indicate that the planetary gear train is a major source of cabin noise and that other low frequency sources are present that could dominate the cabin noise. Companion vibration measurements were made in a transmission test stand, revealing that the single largest contributor to the transmission vibration was the spiral bevel gear mesh. The current understanding of the nature and causes of gear and transmission noise is discussed. It is believed that the kinematical errors of the gear mesh have a strong influence on that noise. The completed NASA/Army sponsored research that applies to transmission noise reduction is summarized. The continuing research program is also reviewed.

Identification and proposed control of helicopter transmission noise at the source

NASA Technical Reports Server (NTRS)

Coy, John J.; Handschuh, Robert F.; Lewicki, David G.; Huff, Ronald G.; Krejsa, Eugene A.; Karchmer, Allan M.

1987-01-01

Helicopter cabin interiors require noise treatment which is expensive and adds weight. The gears inside the main power transmission are major sources of cabin noise. Work conducted by the NASA Lewis Research Center in measuring cabin interior noise and in relating the noise spectrum to the gear vibration of the Army OH-58 helicopter is described. Flight test data indicate that the planetary gear train is a major source of cabin noise and that other low frequency sources are present that could dominate the cabin noise. Companion vibration measurements were made in a transmission test stand, revealing that the single largest contributor to the transmission vibration was the spiral bevel gear mesh. The current understanding of the nature and causes of gear and transmission noise is discussed. It is believed that the kinematical errors of the gear mesh have a strong influence on that noise. The completed NASA/Army sponsored research that applies to transmission noise reduction is summarized. The continuing research program is also reviewed.

Altitude-Related Change in Endotracheal Tube Cuff Pressures in Helicopter EMS.

PubMed

Weisberg, Stacy N; McCall, Jonathan C; Tennyson, Joseph

2017-06-01

Over-inflation of endotracheal tube (ETT) cuffs has the potential to lead to scarring and stenosis of the trachea.1, 2,3, 4 The air inside an ETT cuff is subject to expansion as atmospheric pressure decreases, as happens with an increase in altitude. Emergency medical services helicopters are not pressurized, thereby providing a good environment for studying the effects of altitude changes ETT cuff pressures. This study aims to explore the relationship between altitude and ETT cuff pressures in a helicopter air-medical transport program. ETT cuffs were initially inflated in a nonstandardized manner and then adjusted to a pressure of 25 cmH 2 O. The pressure was again measured when the helicopter reached maximum altitude. A final pressure was recorded when the helicopter landed at the receiving facility. We enrolled 60 subjects in the study. The mean for initial tube cuff pressures was 70 cmH 2 O. Maximum altitude for the program ranged from 1,000-3,000 feet above sea level, with a change in altitude from 800-2,480 feet. Mean cuff pressure at altitude was 36.52 ± 8.56 cmH 2 O. Despite the significant change in cuff pressure at maximum altitude, there was no relationship found between the maximum altitude and the cuff pressures measured. Our study failed to demonstrate the expected linear relationship between ETT cuff pressures and the maximum altitude achieved during typical air-medical transportation in our system. At altitudes less than 3,000 feet above sea level, the effect of altitude change on ETT pressure is minimal and does not require a change in practice to saline-filled cuffs.

75 FR 52914 - Airworthiness Directives; Bell Helicopter Textron Canada Limited Models 206A, 206B, 206L, 206L-1...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-30

... Textron Canada Limited Models 206A, 206B, 206L, 206L-1, 206L-3, and 206L-4 Helicopters AGENCY: Federal... Part Number (P/N) 101584-1 or -2, sold through Bell Helicopter Spares beginning March 2009, as an alternate to P/N 32721-1, does not conform to the approved configuration. Operating a helicopter with disk...

EMS helicopter incidents reported to the NASA Aviation Safety Reporting System

NASA Technical Reports Server (NTRS)

Connell, Linda J.; Reynard, William D.

1993-01-01

The objectives of this evaluation were to: Identify the types of safety-related incidents reported to the Aviation Safety Reporting System (ASRS) in Emergency Medical Service (EMS) helicopter operations; Describe the operational conditions surrounding these incidents, such as weather, airspace, flight phase, time of day; and Assess the contribution to these incidents of selected human factors considerations, such as communication, distraction, time pressure, workload, and flight/duty impact.

Reduction of Helicopter BVI Noise, Vibration, and Power Consumption Through Individual Blade Control

NASA Technical Reports Server (NTRS)

Jacklin, Stephen A.; Blaas, Achim; Teves, Dietrich; Kube, Roland; Warmbrodt, William (Technical Monitor)

1994-01-01

A wind tunnel test was conducted with a full-scale BO 105 helicopter rotor to evaluate the potential of open-loop individual blade control (IBC) to improve rotor performance, to reduce blade vortex interaction (BVI) noise, and to alleviate helicopter vibrations. The wind tunnel test was an international collaborative effort between NASA/U.S. Army AFDD, ZF Luftfahrttechnik, Eurocopter Deutschland, and the German Aerospace Laboratory (DLR) and was conducted under the auspices of the U.S./German MOU on Rotorcraft Aeromechanics. In this test the normal blade pitch links of the rotor were replaced by servo-actuators so that the pitch of each blade could be controlled independently of the other blades. The specially designed servoactuators and IBC control system were designed and manufactured by ZF Luftfahrttechnik, GmbH. The wind tunnel test was conducted in the 40- by 80-Foot Wind Tunnel at the NASA Ames Research Center. An extensive amount of measurement information was acquired for each IBC data point. These data include rotor performance, static and dynamic hub forces and moments, rotor loads, control loads, inboard and outboard blade pitch motion, and BVI noise data. The data indicated very significant (80 percent) simultaneous reductions in both BVI noise and hub vibrations could be obtained using multi-harmonic input at the critical descent (terminal approach) condition. The data also showed that performance improvements of up to 7 percent could be obtained using 2P input at high-speed forward flight conditions.

Whole body vibration in helicopters: risk assessment in relation to low back pain.

PubMed

Kåsin, Jan Ivar; Mansfield, Neil; Wagstaff, Anthony

2011-08-01

Helicopter pilots are exposed to whole body vibration (WBV) in their working environment. WBV has been associated with low back pain (LBP) and helicopter pilots have a high prevalence for LBP compared with other professions. The aim of this study was to develop a test protocol for measuring helicopters with ISO 2631-1 and to perform a whole body vibration risk assessment based on the European Vibration Directive in a number of commonly used military and civilian helicopters. Both absolute values and individual difference in current helicopter types are of interest in order to evaluate the possible role of vibration in LBP in helicopter pilots. In operationally relevant maneuvers, six helicopters were tested. In order to standardize measurements, each continuous flight was split into 15 separate maneuvers. A model of a working day exposure pattern was used to calculate A(8) vibration magnitudes for each helicopter. The vibration A(8) exposure estimates ranged from 0.32-0.51 m x s(-2) during an 8-h working day A(8). This compares with EU and ISO lower bounds risk criteria of 0.5 and 0.43 m x s(-2) A(8), respectively. Despite the vibration levels being relatively low, helicopter pilots report a high incidence of LBP. It is possible that helicopter pilot postures increase the risk of LBP when combined with WBV. The test protocol used in this study could be generally applied for other rotary winged aircraft testing to allow for comparison of WBV results. Data from different flight phases could be used to model different exposure profiles.

A helicopter flight does not induce significant changes in systemic biomarker profiles.

PubMed

Kåsin, Jan Ivar; Kjekshus, John; Aukrust, Pål; Mollnes, Tom Eirik; Wagstaff, Anthony

2009-01-01

Whole-body vibration and noise are inherent characteristics of helicopter operations. The helicopter pilot is affected by vibration from both low-frequency noise and mechanical vibration sources. The way this energy is transmitted to different tissues and organs depends on intensity, frequency and resonance phenomena within the body. Whole-body vibration is known to affect the muscular and skeletal system in the lower part of the spine, but less is known about the response at the cellular level to this stimulation. In some studies, chronic pathological changes have been described in different types of tissue in people exposed to low-frequency noise and vibration. The aim of the present study was to investigate possible cellular reactions to acute exposure to low-frequency noise and vibration in a helicopter. Thirteen healthy males aged 38 (18-69) years were subjected to a 3.5 h helicopter flight in a Westland Sea King Rescue helicopter. Blood tests taken before and after the flight were analysed for more than 40 parameters, including acute phase reactants, markers of leucocyte and platelet activation, complement and hemostasis markers, as well as a broad panel of cytokines, chemokines, growth factors and cell adhesion molecules. The subjects served as their own controls. With the exception of an increase in vascular cell adhesion molecule-1 (VCAM-1) during the flight, no statistically significant changes in the biomarkers were found after controlling for diurnal variation in the control blood tests, which were observed independently of the helicopter flight. In conclusion, one helicopter flight does not induce measurable changes in systemic biomarkers.

Helicopter In-Flight Tracking System (HITS) for the Gulf of Mexico

NASA Technical Reports Server (NTRS)

Martone, Patrick; Tucker, George; Aiken, Edwin W. (Technical Monitor)

2001-01-01

The National Aeronautics and Space Administration (NASA) Ames Research Center (ARC) is sponsoring deployment and testing of the Helicopter In-flight Tracking System (HITS) in a portion of the Gulf of Mexico offshore area. Using multilateration principles, HITS determines the location and altitude of all transponder-equipped aircraft without requiring changes to current Mode A, C or S avionics. HITS tracks both rotary and fixed-wing aircraft operating in the 8,500 sq. mi. coverage region. The minimum coverage altitude of 100 ft. is beneficial for petroleum industry, allowing helicopters to be tracked onto the pad of most derricks. In addition to multilateration, HITS provides surveillance reports for aircraft equipped for Automatic Dependent Surveillance - Broadcast (ADS-B), a new surveillance system under development by the Federal Aviation Administration (FAA). The U.S. Department of Transportation (DOT) Volpe National Transportation Systems Center (Volpe Center) is supporting NASA in managing HITS installation and operation, and in evaluating the system's effectiveness. Senses Corporation is supplying, installing and maintaining the HITS ground system. Project activities are being coordinated with the FAA and local helicopter operators. Flight-testing in the Gulf will begin in early 2002. This paper describes the HITS project - specifically, the system equipment (architecture, remote sensors, central processing system at Intracoastal City, LA, and communications) and its performance (accuracy, coverage, and reliability). The paper also presents preliminary results of flight tests.

Maneuver Acoustic Flight Test of the Bell 430 Helicopter Data Report

NASA Technical Reports Server (NTRS)

Watts, Michael E.; Greenwood, Eric; Smith, Charles D.; Snider, Royce; Conner, David A.

2014-01-01

A cooperative ight test by NASA, Bell Helicopter and the U.S. Army to characterize the steady state acoustics and measure the maneuver noise of a Bell Helicopter 430 aircraft was accomplished. The test occurred during June/July 2011 at Eglin Air Force Base, Florida. This test gathered a total of 410 test points over 10 test days and compiled an extensive database of dynamic maneuver measurements. Three microphone arrays with up to 31 microphon. es in each were used to acquire acoustic data. Aircraft data included Differential Global Positioning System, aircraft state and rotor state information. This paper provides an overview of the test and documents the data acquired.

Vehicle for civil helicopter ride quality research

NASA Technical Reports Server (NTRS)

Snyder, W. J.; Schlegel, R. G.

1975-01-01

A research aircraft for investigating the factors involved in civil helicopter operations was developed for NASA Langley Research Center. The aircraft is a reconfigured 17000 kg (36000 lb) military transport helicopter. The basic aircraft was reconfigured with advanced acoustic treatment, air-conditioning, and a 16-seat airline cabin. During the spring of 1975, the aircraft was flight tested to measure interior environment characteristics - noise and vibration - and was flown on 60 subjective flight missions with over 600 different subjects. Data flights established noise levels somewhat higher than expected, with a pure tone at 1400 Hz and vertical vibration levels between 0.07g and 0.17g. The noise and vibration levels were documented during subjective flight evaluations as being the primary source of discomfort. The aircraft will be utilized to document in detail the impact of various noise and vibration levels on passenger comfort during typical short-haul missions.

Feasibility and concept study to convert the NASA/AMES vertical motion simulator to a helicopter simulator

NASA Technical Reports Server (NTRS)

Belsterling, C. A.; Chou, R. C.; Davies, E. G.; Tsui, K. C.

1978-01-01

The conceptual design for converting the vertical motion simulator (VMS) to a multi-purpose aircraft and helicopter simulator is presented. A unique, high performance four degrees of freedom (DOF) motion system was developed to permanently replace the present six DOF synergistic system. The new four DOF system has the following outstanding features: (1) will integrate with the two large VMS translational modes and their associated subsystems; (2) can be converted from helicopter to fixed-wing aircraft simulation through software changes only; (3) interfaces with an advanced cab/visual display system of large dimensions; (4) makes maximum use of proven techniques, convenient materials and off-the-shelf components; (5) will operate within the existing building envelope without modifications; (6) can be built within the specified weight limit and avoid compromising VMS performance; (7) provides maximum performance with a minimum of power consumption; (8) simple design minimizes coupling between motions and maximizes reliability; and (9) can be built within existing budgetary figures.

Aerodynamic Interaction Effects of a Helicopter Rotor and Fuselage

NASA Technical Reports Server (NTRS)

Boyd, David D., Jr.

1999-01-01

A three year Cooperative Research Agreements made in each of the three years between the Subsonic Aerodynamics Branch of the NASA Langley Research Center and the Virginia Polytechnic Institute and State University (Va. Tech) has been completed. This document presents results from this three year endeavor. The goal of creating an efficient method to compute unsteady interactional effects between a helicopter rotor and fuselage has been accomplished. This paper also includes appendices to support these findings. The topics are: 1) Rotor-Fuselage Interactions Aerodynamics: An Unsteady Rotor Model; and 2) Rotor/Fuselage Unsteady Interactional Aerodynamics: A New Computational Model.

Use of an ambulance-based helicopter retrieval service.

PubMed

Wills, V L; Eno, L; Walker, C; Gani, J S

2000-07-01

John Hunter Hospital is the major trauma centre for a region covering more than 25,000 square kilometres. The helicopter primary retrieval service for trauma is paramedic staffed and protocol driven. The aim of the present study was to assess the overtriage rate created by such protocols, and to assess the benefit to patient outcomes that may be attributable to the service. The John Hunter Hospital trauma database was used to identify all cases arriving by helicopter in 1996, as well as their demographic details, injury severity score, details of the accident and outcome. An expert panel reviewed the medical records for the 184 primary retrievals. Using a consensus model, estimates of time delay or saving were calculated and likelihood of benefit, no benefit or harm was assessed. A total of 3087 trauma patients were assessed at John Hunter Hospital in 1996, of which 8% arrived by helicopter. Of the primary retrievals, 67.6% had an injury severity score of 9 or less, with only 17.9% having a score of 16 or greater. Twelve patients were discharged from Emergency and 36% were discharged within 48 h. The overall mortality was 5.0%. Twenty-five per cent of patients were retrieved within 35 km of John Hunter Hospital with minimal attributable benefit. Overall 1.7% of patients were felt to have been potentially harmed, 17.3% to have benefited and 81.0% to have had no attributable benefit related to the helicopter use. Although the majority of retrievals are for minor injuries, the service provides benefit for the region. There is potential for harm, however, where base hospitals are overflown in situations where patients have airway compromise, and where patient transfer is delayed due to helicopter activation. Primary helicopter tasking to trauma cases within 35 km of the major trauma centre is seldom beneficial.

Magnesium-dependent association and folding of oligonucleosomes reconstituted with ubiquitinated H2A.

PubMed

Jason, L J; Moore, S C; Ausio, J; Lindsey, G

2001-05-04

The MgCl2-induced folding of defined 12-mer nucleosomal arrays, in which ubiquitinated histone H2A (uH2A) replaced H2A, was analyzed by quantitative agarose gel electrophoresis and analytical centrifugation. Both types of analysis showed that uH2A arrays attained a degree of compaction similar to that of control arrays in 2 mM MgCl2. These results indicate that attachment of ubiquitin to H2A has little effect on the ability of nucleosomal arrays to form higher order folded structures in the ionic conditions tested. In contrast, uH2A arrays were found to oligomerize at lower MgCl2 concentrations than control nucleosomal arrays, suggesting that histone ubiquitination may play a role in nucleosomal fiber association.

Astronaut John Young hoisted aboard helicopter during water egress training

NASA Image and Video Library

1966-06-18

S66-39713 (18 June 1966) --- Astronaut John W. Young, Gemini-10 command pilot, is hoisted up to a U.S. Coast Guard helicopter during water egress training in the Gulf of Mexico. A team of Manned Spaceflight Center (MSC) swimmers assists in the exercise. The Static Article 5 spacecraft can be seen in the water. Photo credit: NASA

77 FR 27116 - Safety Zone, Naval Helicopter Association Reunion Helicopter Demonstration, Elizabeth River...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-09

...-AA00 Safety Zone, Naval Helicopter Association Reunion Helicopter Demonstration, Elizabeth River... establishing a temporary safety zone on the Elizabeth River in the vicinity of Norfolk, VA to support the Naval... of life on navigable waters during the Naval Helicopter Association Reunion Helicopter Demonstration...

The making of helicopters: its strategic implications for EMS helicopter operations.

PubMed

Thomas, F

1998-01-01

The purpose of this article is to provide EMS helicopter personnel with an understanding of the civil helicopter manufacturing industry. Specifically, this article examines the current helicopter marketplace and how various manufactures are responding to the recent decline in new helicopter sales. This article further describes how helicopters are designed and manufactured and how global markets, international competition, and strategic considerations are influencing future helicopter design and production. Data for this paper were obtained from a literature search through the ABI-inform Telnet Services offered through the University of Utah Marriott Library. On a search of "helicopter" during the past 5 years, 566 abstracts were identified, all of which were reviewed for information related to the purpose of this article. Forty-seven articles were identified and read in detail for information that may have related to the purpose of this article. In addition, a library search to identify textbooks that describe helicopter production systems was undertaken but did not identify any written resources. Because of the lack of written resources available in writing this article, a direct interview survey of leading helicopter manufactures, associations, and industry writers was conducted. Only information that was considered "public knowledge" was available because of concerns by the various manufactures that publication of confidential information could be detrimental to their competitive advantage. Because helicopter-manufacturing plants were not located within easy travel range, no direct observation of the production facilities could be undertaken. Furthermore, information regarding production and operational management was not easily accessible because the data were not published or were considered confidential. Therefore industry analysis had to take place through direct survey interviewing technique and data obtained through an analysis of the available published

Experimental observations of nonlinearly enhanced 2omega-UH electromagnetic radiation excited by steady-state colliding electron beams

NASA Technical Reports Server (NTRS)

Intrator, T.; Hershkowitz, N.; Chan, C.

1984-01-01

Counterstreaming large-diameter electron beams in a steady-state laboratory experiment are observed to generate transverse radiation at twice the upper-hybrid frequency (2omega-UH) with a quadrupole radiation pattern. The electromagnetic wave power density is nonlinearly enhanced over the power density obtained from a single beam-plasma system. Electromagnetic power density scales exponentially with beam energy and increases with ion mass. Weak turbulence theory can predict similar (but weaker) beam energy scaling but not the high power density, or the predominance of the 2omega-UH radiation peak over the omega-UH peak. Significant noise near the upper-hybrid and ion plasma frequencies is also measured, with normalized electrostatic wave energy density W(ES)/n(e)T(e) approximately 0.01.

Altitude-Related Change in Endotracheal Tube Cuff Pressures in Helicopter EMS

PubMed Central

Weisberg, Stacy N.; McCall, Jonathan C.; Tennyson, Joseph

2017-01-01

Introduction Over-inflation of endotracheal tube (ETT) cuffs has the potential to lead to scarring and stenosis of the trachea.1, 2,3, 4 The air inside an ETT cuff is subject to expansion as atmospheric pressure decreases, as happens with an increase in altitude. Emergency medical services helicopters are not pressurized, thereby providing a good environment for studying the effects of altitude changes ETT cuff pressures. This study aims to explore the relationship between altitude and ETT cuff pressures in a helicopter air-medical transport program. Methods ETT cuffs were initially inflated in a nonstandardized manner and then adjusted to a pressure of 25 cmH2O. The pressure was again measured when the helicopter reached maximum altitude. A final pressure was recorded when the helicopter landed at the receiving facility. Results We enrolled 60 subjects in the study. The mean for initial tube cuff pressures was 70 cmH2O. Maximum altitude for the program ranged from 1,000–3,000 feet above sea level, with a change in altitude from 800–2,480 feet. Mean cuff pressure at altitude was 36.52 ± 8.56 cmH2O. Despite the significant change in cuff pressure at maximum altitude, there was no relationship found between the maximum altitude and the cuff pressures measured. Conclusion Our study failed to demonstrate the expected linear relationship between ETT cuff pressures and the maximum altitude achieved during typical air-medical transportation in our system. At altitudes less than 3,000 feet above sea level, the effect of altitude change on ETT pressure is minimal and does not require a change in practice to saline-filled cuffs. PMID:28611883

Ultrareliable fault-tolerant control systems

NASA Technical Reports Server (NTRS)

Webster, L. D.; Slykhouse, R. A.; Booth, L. A., Jr.; Carson, T. M.; Davis, G. J.; Howard, J. C.

1984-01-01

It is demonstrated that fault-tolerant computer systems, such as on the Shuttles, based on redundant, independent operation are a viable alternative in fault tolerant system designs. The ultrareliable fault-tolerant control system (UFTCS) was developed and tested in laboratory simulations of an UH-1H helicopter. UFTCS includes asymptotically stable independent control elements in a parallel, cross-linked system environment. Static redundancy provides the fault tolerance. A polling is performed among the computers, with results allowing for time-delay channel variations with tight bounds. When compared with the laboratory and actual flight data for the helicopter, the probability of a fault was, for the first 10 hr of flight given a quintuple computer redundancy, found to be 1 in 290 billion. Two weeks of untended Space Station operations would experience a fault probability of 1 in 24 million. Techniques for avoiding channel divergence problems are identified.

Member of Apollo 7 crew hoisted to helicopter during recovery operations

NASA Image and Video Library

1968-10-22

S68-49661 (22 Oct. 1968) --- A member of the Apollo 7 crew is hoisted up to a recovery helicopter from the USS Essex during recovery operations. The Apollo 7 spacecraft splashed down at 7:11 a.m., Oct. 22, 1968, approximately 200 nautical miles south-southwest of Bermuda. Photo credit: NASA

Fuel-conservation evaluation of US Army helicopters. Part 6. Performance calculator evaluation. Final report for period ending January 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dominick, F.; Lockwood, R.A.

1986-07-01

The US Army Aviation Engineering Flight Activity conducted an evaluation of Flight Management Calculator for the UH-1H. The calculator was a Hewlett-Packard HP-41CV. The performance calculator was evaluated for flight planning and in-flight use during 14 mission flights simulating operational conditions. The calculator was much easier to use in-flight than the operator's manual data. The calculator program needs improvement in the areas of pre-flight planning and execution speed. The mission flights demonstrated a 19% fuel saving using optimum over normal flight profiles in warm temperatures (15/sup 0/C above standard). Savings would be greater at colder temperatures because of increasing compressibilitymore » effects. Acceptable accuracy for individual aircraft under operational conditions may require a regressive analog model in which individual aircraft data are used to update the program. The performance data base for the UH-1H was expanded with level flight and hover data to thrust coefficients and Mach numbers to the practical limits of aircraft operation.« less

77 FR 44118 - Airworthiness Directives; Eurocopter France Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-27

... Airworthiness Directives; Eurocopter France Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Eurocopter France (Eurocopter) Model EC155B1 helicopters with a certain... Determination These helicopters have been approved by the aviation authority of France and are approved for...

4H-and-NASA-Leadership-Followership

NASA Image and Video Library

2017-05-09

Lots of people like to be the leader, but leaders need a team to follow them. Understanding when to lead and when to follow, and the importance of both roles, is a critical skill for success. To learn more visit www.nasa.gov/education/4H.

Main rotor free wake geometry effects on blade air loads and response for helicopters in steady maneuvers. Volume 2: Program listings

NASA Technical Reports Server (NTRS)

Sadler, S. G.

1972-01-01

A mathematical model and computer program was implemented to study the main rotor free wake geometry effects on helicopter rotor blade air loads and response in steady maneuvers. Volume 1 (NASA CR-2110) contains the theoretical formulation and analysis of results. Volume 2 contains the computer program listing.

Helicopter human factors

NASA Technical Reports Server (NTRS)

Hart, Sandra G.

1988-01-01

The state-of-the-art helicopter and its pilot are examined using the tools of human-factors analysis. The significant role of human error in helicopter accidents is discussed; the history of human-factors research on helicopters is briefly traced; the typical flight tasks are described; and the noise, vibration, and temperature conditions typical of modern military helicopters are characterized. Also considered are helicopter controls, cockpit instruments and displays, and the impact of cockpit design on pilot workload. Particular attention is given to possible advanced-technology improvements, such as control stabilization and augmentation, FBW and fly-by-light systems, multifunction displays, night-vision goggles, pilot night-vision systems, night-vision displays with superimposed symbols, target acquisition and designation systems, and aural displays. Diagrams, drawings, and photographs are provided.

The X-40 sub-scale technology demonstrator is suspended under a U.S. Army CH-47 Chinook cargo helicopter during a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California.

NASA Image and Video Library

2000-12-08

The X-40 sub-scale technology demonstrator is suspended under a U.S. Army CH-47 Chinook cargo helicopter during a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles.

78 FR 23462 - Airworthiness Directives; Eurocopter France Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-19

... Airworthiness Directives; Eurocopter France Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Eurocopter France (Eurocopter) Model AS332C, AS332L, and AS332L1 helicopters... helicopters have been approved by the aviation authority of France and are approved for operation in the...

Handling Qualities Specifications for U.S. Military Helicopters

NASA Technical Reports Server (NTRS)

Key, David L.

1982-01-01

Inadequacies in the military specification for helicopter handling qualities, MIL-H-8501A, have long been recognized, and the latest procurements by the U.S. Army used special Prime Item Development Specifications (PIDS). This paper assesses the efficacy of these PIDS and suggests that changes should be made. In particular, the structure developed in MIL-F-8785B (ASG) (the specification for flying qualities of piloted airplanes) should be incorporated. Improved requirements must be based on a systematic data base and concentrated on topics most important in preliminary design: static and dynamic stability, control power and sensitivity, and interaction with controllers and displays. Emphasis should be on current military helicopter missions and helicopter idiosyncrasies such as cross-coupling, nonlinearities, and higher-order dynamics.

Poster presentation Sandia helicopter acoustic detector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arlowe, H.D.

1981-01-01

In reviewing the safeguards plans for several proposed fuel cycle facilities, the advantages of a short-range helicopter detector became apparent. The main buildings of these new designs are generally hardened so as to provide significant delay to a helicopter-borne adversary team. Under these circumstances the sensor is only required to detect helicopters which are in their final landing phase and at close range (less than 75 meters). This paper describes the Sandia detector, which is designed to only look at spectral lines between 20 and 40 Hz, and depends upon the harmonic content of the rotor pulses for detecting themore » lower rotor speed helicopters. 1 ref.« less

The NASA radar entomology program at Wallops Flight Center

NASA Technical Reports Server (NTRS)

Vaughn, C. R.

1979-01-01

NASA contribution to radar entomology is presented. Wallops Flight Center is described in terms of its radar systems. Radar tracking of birds and insects was recorded from helicopters for airspeed and vertical speed.

USMC Electronic Warfare 2025: Trading Expertise for Advanced Technology

DTIC Science & Technology

2011-04-15

REFERENCES TO THIS STUDY SHOULD INCLUDE THE FOREGOING STATEMENT. QUOTATIONS FROM, ABSTRACTIONS FROM, OR REPRODUCTION OF ALL OR ANY PART OF THIS...formed with the.use of helicopters as nodes, including: MV-22B Ospreys, UH-1 Y Venoms, AH-1Z Vipers and CH-53K Super Stallions . The conceived benefits of

14 CFR 29.71 - Helicopter angle of glide: Category B.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting the...

14 CFR 29.71 - Helicopter angle of glide: Category B.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting the...

14 CFR 29.71 - Helicopter angle of glide: Category B.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting the...

14 CFR 29.71 - Helicopter angle of glide: Category B.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting the...

14 CFR 29.71 - Helicopter angle of glide: Category B.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Helicopter angle of glide: Category B. 29... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.71 Helicopter angle of glide: Category B. For each category B helicopter, except multiengine helicopters meeting the...

Getting the Best Value in a Source Selection

DTIC Science & Technology

2015-12-01

leadership, for both civilian and military program managers . Army COL James C. Mills relieved COL Gary D. Stephens as project manager for the...Precision Fires Rocket and Missile Systems (PFRMS) on July 15. COL William D. Jackson relieved COL Thomas H. Todd as project manager for Utility...Helicopters (UH) on July 15. COL Shane N. Fullmer relieved COL John Cavedo, Jr. as project manager for Joint Program Office, Joint Light Tactical Vehicles

Toward the silent helicopter

NASA Astrophysics Data System (ADS)

Lewy, Serge; Marze, Henri-James

The development of a 'silent helicopter' program in Europe, whose aim would be noise reduction for both commercial and military helicopters over the next five years, is discussed. Attention is given to acoustic constraints for helicopters and to noise reduction techniques (with particular reference to the main rotor, the rear rotor, and the engines). For commercial helicopters, the noise reduction over the next five years is projected to be at least down to 6 dB below the OACI norms; for military helicopters, the aim is a variable-frequency signature in near-tactical-flight conditions, with a factor-of-two reduction in the maximum impulsivity in the far field.

NASA transmission research and its probable effects on helicopter transmission design

NASA Technical Reports Server (NTRS)

Zaretsky, E. V.; Coy, J. J.; Townsend, D. P.

1983-01-01

Transmissions studied for application to helicopters in addition to the more conventional geared transmissions include hybrid (traction/gear), bearingless planetary, and split torque transmissions. Research is being performed to establish the validity of analysis and computer codes developed to predict the performance, efficiency, life, and reliability of these transmissions. Results of this research should provide the transmission designer with analytical tools to design for minimum weight and noise with maximum life and efficiency. In addition, the advantages and limitations of drive systems as well as the more conventional systems will be defined.

NASA transmission research and its probable effects on helicopter transmission design

NASA Technical Reports Server (NTRS)

Zaretsky, E. V.; Coy, J. J.; Townsend, D. P.

1984-01-01

Transmissions studied for application to helicopters in addition to the more conventional geared transmissions include hybrid (traction/gear), bearingless planetary, and split torque transmissions. Research is being performed to establish the validity of analysis and computer codes developed to predict the performance, efficiency, life, and reliability of these transmissions. Results of this research should provide the transmission designer with analytical tools to design for minimum weight and noise with maximum life and efficiency. In addition, the advantages and limitations of drive systems as well as the more conventional systems will be defined.

Experimental study of performance degradation of a rotating system in the NASA Lewis RC icing tunnel

NASA Technical Reports Server (NTRS)

Korkan, Kenneth

1992-01-01

The Helicopter Icing Consortium (HIC) conducted one of the first U.S. tests of a heavily instrumented model in the controlled environment of a refrigerated tunnel. In the Icing Research Tunnel (IRT) at NASA LeRC, ice was accreted on the main rotor blade of the BMTR-1 Sikorsky model helicopter under a variety of environmental conditions, such that liquid water content (LWC) and volume mean droplet diameter (VMD) ranges reflected the Federal Aviation Agency and Department of Defence icing condition envelopes. This report gives the correlated results of the data provided by NASA LeRC. The method of statistical analysis is discussed. Lift, thrust, and torque coefficients are presented as a function of icing time, as correlated with changes in ambient temperature, LWC, and VMD. The physical significance of these forces is discussed.

Price Determination of General Aviation, Helicopter, and Transport Aircraft

NASA Technical Reports Server (NTRS)

Anderson, Joseph L.

1978-01-01

The NASA must assess its aeronautical research program with economic as well as performance measures. It thus is interested in what price a new technology aircraft would carry to make it attractive to the buyer. But what price a given airplane or helicopter will carry is largely a reflection of the manufacturer's assessment of the competitive market into which the new aircraft will be introduced. The manufacturer must weigh any new aerodynamic or system technology innovation he would add to an aircraft by the impact of this innovation upon the aircraft's economic attractiveness and price. The intent of this paper is to give price standards against which new technologies and the NASA's research program can be assessed. Using reported prices for general aviation, helicopter, and transport aircraft, price estimating relations in terms of engine and airframe characteristics have been developed. The relations are given in terms of the aircraft type, its manufactured empty weight, engine weight, horsepower or thrust. Factors for the effects of inflation are included to aid in making predictions of future aircraft prices. There are discussions of aircraft price in terms of number of passenger seats, airplane size and research and development costs related to an aircraft model, and indirectly as to how new technologies, aircraft complexity and inflation have affected these.

An investigation of the effects of pitch-roll (de)-coupling on helicopter handling qualities

NASA Technical Reports Server (NTRS)

Ockier, C. J.; Pausder, H. J.; Blanken, C. L.

1995-01-01

An investigation of the effects of pitch-roll coupling on helicopter handling qualities was performed by the US Army and DLR, using a NASA ground-based and a DLR inflight simulator. Over 90 different coupling configurations were evaluated using a roll-axis tracking task. The results show that although the current ADS-33C coupling criterion discriminates against those types of coupling typical of conventionally controlled helicopters, it not always suited for the prediction of handling qualities of helicopters with modern control systems. Based on the observation that high frequency inputs during tracking are used to alleviate coupling, a frequency domain pitch-roll coupling criterion that uses the average coupling ratio between the bandwidth and neutral stability frequency is formulated. This criterion provides a more comprehensive coverage with respect to the different types of coupling and shows excellent consistency.

Full-Scale Crash Test of an MD-500 Helicopter

NASA Technical Reports Server (NTRS)

Littell, Justin

2011-01-01

A full-scale crash test was successfully conducted in March 2010 of an MD-500 helicopter at NASA Langley Research Center s Landing and Impact Research Facility. The reasons for conducting this test were threefold: 1 To generate data to be used with finite element computer modeling efforts, 2 To study the crashworthiness features typically associated with a small representative helicopter, and 3 To compare aircraft response to data collected from a previously conducted MD-500 crash test, which included an externally deployable energy absorbing (DEA) concept. Instrumentation on the airframe included accelerometers on various structural components of the airframe; and strain gages on keel beams, skid gear and portions of the skin. Three Anthropomorphic Test Devices and a specialized Human Surrogate Torso Model were also onboard to collect occupant loads for evaluation with common injury risk criteria. This paper presents background and results from this crash test conducted without the DEA concept. These results showed accelerations of approximately 30 to 50 g on the airframe at various locations, little energy attenuation through the airframe, and moderate to high probability of occupant injury for a variety of injury criteria.

Implementing the UH Asynchronous Learning Network: Practices, Issues and Challenges

ERIC Educational Resources Information Center

Odin, Jaishree K.

2002-01-01

In spite of ten campuses spread over four islands, access to higher education at the University of Hawai'i (UH) is unevenly distributed across the state. In an effort to address the problem of access, the Alfred P. Sloan Foundation has funded the University of Hawai'i to develop online courses and programs. In this article, the author describes…

Computer simulation of multiple pilots flying a modern high performance helicopter

NASA Technical Reports Server (NTRS)

Zipf, Mark E.; Vogt, William G.; Mickle, Marlin H.; Hoelzeman, Ronald G.; Kai, Fei; Mihaloew, James R.

1988-01-01

A computer simulation of a human response pilot mechanism within the flight control loop of a high-performance modern helicopter is presented. A human response mechanism, implemented by a low order, linear transfer function, is used in a decoupled single variable configuration that exploits the dominant vehicle characteristics by associating cockpit controls and instrumentation with specific vehicle dynamics. Low order helicopter models obtained from evaluations of the time and frequency domain responses of a nonlinear simulation model, provided by NASA Lewis Research Center, are presented and considered in the discussion of the pilot development. Pilot responses and reactions to test maneuvers are presented and discussed. Higher level implementation, using the pilot mechanisms, are discussed and considered for their use in a comprehensive control structure.

Evaluation of Wind Tunnel and Scaling Effects with the UH-60A Airloads Rotor

DTIC Science & Technology

2011-05-01

V! free-stream velocity, ft/s x chordwise distance from leading edge, ft #c, #s corrected/geometric shaft angles, deg $1c, $1s cos/sin components...attached to spindles that were retained by elastomeric bearings to a one-piece titanium hub. These bearings permitted blade flap, lead-lag, and...Figure 3. UH-60A small-scale rotor installed in DNW. Main rotor dampers were installed between each of the main rotor spindles and the hub to

Failure Analysis of a Helicopter External Fuel-Tank Pylon

NASA Technical Reports Server (NTRS)

Newman, John A.; Piascik, Robert S.; Lindenberg, Richard A.

2002-01-01

An eight-inch-long (0.2 m) crack was found in an external fuel-tank pylon of a U.S. Coast Guard HH-60 helicopter. The damaged pylon was removed from service and destructively examined at NASA Langley Research Center (LaRC) to determine the cause of the crack. Results of the analysis revealed that crack initiation occurred at corrosion pits in a fastener hole and crack propagation was a result of cyclic loading.

Lubricant Effects on Efficiency of a Helicopter Transmission

NASA Technical Reports Server (NTRS)

Mitchell, A. M.; Coy, J. J.

1982-01-01

Eleven different lubricants were used in efficiency tests conducted on the OH-58A helicopter main transmission using the NASA Lewis Research Center's 500 hp torque regenerative helicopter transmission test stand. Tests were run at oil-in temperatures of 355 K and 372 K. The efficiency was calculated from a heat balance on the water running through an oil to water heat exchanger which the transmission was heavily insulated. Results show an efficiency range from 98.3% to 98.8% which is a 50% variation relative to the losses associated with the maximum efficiency measured. For a given lubricant, the efficiency increased as temperature increased and viscosity decreased. There were two exceptions which could not be explained. Between lubricants, efficiency was not correlated with viscosity. There were relatively large variations in efficiency with the different lubricants whose viscosity generally fell in the 5 to 7 centistoke range. The lubricants had no significant effect on the vibration signature of the transmission.

Full-Scale Crash Test of a MD-500 Helicopter with Deployable Energy Absorbers

NASA Technical Reports Server (NTRS)

Kellas, Sotiris; Jackson, Karen E.; Littell, Justin D.

2010-01-01

A new externally deployable energy absorbing system was demonstrated during a full-scale crash test of an MD-500 helicopter. The deployable system is a honeycomb structure and utilizes composite materials in its construction. A set of two Deployable Energy Absorbers (DEAs) were fitted on the MD-500 helicopter for the full-scale crash demonstration. Four anthropomorphic dummy occupants were also used to assess human survivability. A demonstration test was performed at NASA Langley's Landing and Impact Research Facility (LandIR). The test involved impacting the helicopter on a concrete surface with combined forward and vertical velocity components of 40-ft/s and 26-ft/s, respectively. The objectives of the test were to evaluate the performance of the DEA concept under realistic crash conditions and to generate test data for validation of dynamic finite element simulations. Descriptions of this test as well as other component and full-scale tests leading to the helicopter test are discussed. Acceleration data from the anthropomorphic dummies showed that dynamic loads were successfully attenuated to within non-injurious levels. Moreover, the airframe itself survived the relatively severe impact and was retested to provide baseline data for comparison for cases with and without DEAs.

Helicopter Handling Qualities

NASA Technical Reports Server (NTRS)

1982-01-01

Helicopters are used by the military and civilian communities for a variety of tasks and must be capable of operating in poor weather conditions and at night. Accompanying extended helicopter operations is a significant increase in pilot workload and a need for better handling qualities. An overview of the status and problems in the development and specification of helicopter handling-qualities criteria is presented. Topics for future research efforts by government and industry are highlighted.

ARC-1981-AC81-0122-2

NASA Image and Video Library

1981-02-25

NASA Aircraft on ramp (Aerial view) Sides: (L) QSRA (R) C-8A AWJSRA - Back to Front: CV-990 (711) C-141 KAO, CV-990 (712) Galileo, T-38, YO-3A, Lear Jet, X-14, U-2, OH-6, CH-47, SH-3G, RSRA, AH-1G, XV-15, UH-1H

Helmet-Mounted Display Research Capabilities of the NASA/Army Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL)

NASA Technical Reports Server (NTRS)

Jacobsen, R. A.; Bivens, C. C.; Rediess, N. A.; Hindson, W. S.; Aiken, E. W.; Aiken, Edwin W. (Technical Monitor)

1995-01-01

The Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) is a UH-60A Black Hawk helicopter that is being modified by the US Army and NASA for flight systems research. The principal systems that are being installed in the aircraft are a Helmet Mounted Display (HMD) and imaging system, and a programmable full authority Research Flight Control System (RFCS). In addition, comprehensive instrumentation of both the rigid body of the helicopter and the rotor system is provided. The paper will describe the capabilities of these systems and their current state of development. A brief description of initial research applications is included. The wide (40 X 60 degree) field-of-view HMD system has been provided by Kaiser Electronics. It can be configured as a monochromatic system for use in bright daylight conditions, a two color system for darker ambients, or a full color system for use in night viewing conditions. Color imagery is achieved using field sequential video and a mechanical color wheel. In addition to the color symbology, high resolution computer-gene rated imagery from an onboard Silicon Graphics Reality Engine Onyx processor is available for research in virtual reality applications. This synthetic imagery can also be merged with real world video from a variety of imaging systems that can be installed easily on the front of the helicopter. These sensors include infrared or tv cameras, or potentially small millimeter wave radars. The Research Flight Control System is being developed for the aircraft by a team of contractors led by Boeing Helicopters. It consists of a full authority high bandwidth fly-by-wire actuators that drive the main rotor swashplate actuators and the tail rotor actuator in parallel. This arrangement allows the basic mechanical flight control system of the Black Hawk to be retained so that the safety pilot can monitor the operation of the system through the action of his own controls. The evaluation pilot will signal the fly

Small Business Innovations (Helicopters)

NASA Technical Reports Server (NTRS)

1992-01-01

The amount of engine power required for a helicopter to hover is an important, but difficult, consideration in helicopter design. The EHPIC program model produces converged, freely distorted wake geometries that generate accurate analysis of wake-induced downwash, allowing good predictions of rotor thrust and power requirements. Continuum Dynamics, Inc., the Small Business Innovation Research (SBIR) company that developed EHPIC, also produces RotorCRAFT, a program for analysis of aerodynamic loading of helicopter blades in forward flight. Both helicopter codes have been licensed to commercial manufacturers.

Design of a Slowed-Rotor Compound Helicopter for Future Joint Service Missions

NASA Technical Reports Server (NTRS)

Silva, Christopher; Yeo, Hyeonsoo; Johnson, Wayne R.

2010-01-01

A slowed-rotor compound helicopter has been synthesized using the NASA Design and Analysis of Rotorcraft (NDARC) conceptual design software. An overview of the design process and the capabilities of NDARC are presented. The benefits of trading rotor speed, wing-rotor lift share, and trim strategies are presented for an example set of sizing conditions and missions.

Advanced Airfoils Boost Helicopter Performance

NASA Technical Reports Server (NTRS)

2007-01-01

Carson Helicopters Inc. licensed the Langley RC4 series of airfoils in 1993 to develop a replacement main rotor blade for their Sikorsky S-61 helicopters. The company's fleet of S-61 helicopters has been rebuilt to include Langley's patented airfoil design, and the helicopters are now able to carry heavier loads and fly faster and farther, and the main rotor blades have twice the previous service life. In aerial firefighting, the performance-boosting airfoils have helped the U.S. Department of Agriculture's Forest Service control the spread of wildfires. In 2003, Carson Helicopters signed a contract with Ducommun AeroStructures Inc., to manufacture the composite blades for Carson Helicopters to sell

Flowfield analysis of modern helicopter rotors in hover by Navier-Stokes method

NASA Technical Reports Server (NTRS)

Srinivasan, G. R.; Raghavan, V.; Duque, E. P. N.

1991-01-01

The viscous, three-dimensional, flowfields of UH60 and BERP rotors are calculated for lifting hover configurations using a Navier-Stokes computational fluid dynamics method with a view to understand the importance of planform effects on the airloads. In this method, the induced effects of the wake, including the interaction of tip vortices with successive blades, are captured as a part of the overall flowfield solution without prescribing any wake models. Numerical results in the form of surface pressures, hover performance parameters, surface skin friction and tip vortex patterns, and vortex wake trajectory are presented at two thrust conditions for UH60 and BERP rotors. Comparison of results for the UH60 model rotor show good agreement with experiments at moderate thrust conditions. Comparison of results with equivalent rectangular UH60 blade and BERP blade indicates that the BERP blade, with an unconventional planform, gives more thrust at the cost of more power and a reduced figure of merit. The high thrust conditions considered produce severe shock-induced flow separation for UH60 blade, while the BERP blade develops more thrust and minimal separation. The BERP blade produces a tighter tip vortex structure compared with the UH60 blade. These results and the discussion presented bring out the similarities and differences between the two rotors.

Flight service evaluation of composite helicopter components

NASA Technical Reports Server (NTRS)

Mardoian, George H.; Ezzo, Maureen B.

1994-01-01

This paper presents the results of a NASA funded contract and Sikorsky research and development programs to evaluate structural composite components in flight service on Sikorsky Model S-76 helicopters. Selected components were removed and tested at prescribed intervals over a nine year time frame. Four horizontal stabilizers and thirteen tail rotor spars were returned from commercial service in West Palm Beach, Florida and in the Gulf Coast region of Louisiana to determine the long term effects of operations in hot and humid climates on component performance. Concurrent with the flight component evaluation, panels of materials used in their fabrication were exposed to the environment in ground racks. Selected panels were tested annually to determine the effects of exposure on physical and mechanical properties. The results of 55,741 component flight hours and 911 months of field exposure are reported and compared with initial Federal Aviation Administration (FAA) certification data. The findings of this program have provided increased confidence in the long term durability of advanced composite materials used in helicopter structural applications.

Crash-resistant fuel system effectiveness in civil helicopter crashes.

PubMed

Hayden, Mark S; Shanahan, Dennis F; Chen, Li-Hui; Baker, Susan P

2005-08-01

Crash-resistant fuel systems (CRFS) have demonstrated close to 100% effectiveness in survivable crashes of Army helicopters, but the technology has been slow to transfer into the civil helicopter arena. Federal standards for civil helicopter CRFS are less stringent than those for military helicopters. A reduction in standards for CRFS in military helicopters is being considered. The goal of this study was to determine whether crashes of civil helicopters with CRFS are less likely to result in post-crash fire than crashes of those without. Crashes of civil helicopters during 1982-2004 were analyzed, comparing Bell 206 helicopters manufactured with CRFS with Aerospatial 350 helicopters manufactured during the same period (post-1981), but lacking CRFS. Bell 206 helicopters with CRFS were also compared with earlier models without CRFS. The highest proportion of crashes with post-crash fires (11.3%) was in AS-350s manufactured after 1981 (non-CRFS), and the lowest (3.7%) was in Bell 206s (with CRFS) [unadjusted risk ratio (RR) = 3.3, 95% confidence interval (CI) = 1.04, 10.50; adjusted for light and weather, RR = 2.81, Cl = 0.82, 9.69]. Earlier models of Bell 206s without CRFS had higher risk of post-crash fire than post-1981 models with CRFS (7.4% vs. 3.7%; adjusted RR = 2.11, Cl = 0.82, 5.45). The results of this study suggest a better performance, in terms of post-crash fire prevention, of CRFS-equipped civil helicopters as compared with those without CRFS. It is possible that CRFS in civil helicopters have not achieved the same degree of effectiveness as CRFS in military helicopters. CRFS should be used more widely in civil helicopters. The more stringent CRFS requirements for military helicopters should not be reduced without further research.

H-1 Upgrades (4BW/4BN) (H-1 Upgrades)

DTIC Science & Technology

2015-12-01

automatic blade fold of the new composite rotor blades, new performance matched transmissions, a new four-bladed tail rotor and drive system, upgraded...Upgrades December 2015 SAR March 18, 2016 10:59:17 UNCLASSIFIED 4 Col Steven Girard PMA-276 USMC Light/Attack Helicopter Program Executive Officer...attack helicopter is to provide rotary wing close air support, anti-armor, armed escort, armed/visual reconnaissance and fire support coordination

Aerial adulticiding for the suppression of Culex tarsalis in Kern County, California, using low-volume propoxur: 1. Selection and evaluation of the application system.

PubMed

Schaefer, C H; Clement, H L; Reisen, W K; Mulligan, F S; Parman, R B; Wilder, W H

1985-06-01

Propoxur applied aerially at 4.7 liters/ha was an effective adulticide against organophosphate resistant Culex tarsalis. Applications by fixed-wing and helicopter underslung spray systems equipped with hydraulic nozzles provided good coverage of test areas as indicated by the mortality patterns of sentinel mosquitoes. However, the propoxur wettable powder in larvicide oil formulation was dispersed in a very broad particle range. The fixed-wing (Ayres Thrush) aircraft treated 260 ha (640 acres) in 45 min and could carry a full load of 1500 liters (400 gal) at temperatures in excess of 38 degrees C. In contrast, the helicopter (Bell UH-1) with an underslung spray system (Simplex Model 6800) required over 2 hrs to treat the same area at lower temperatures and could not carry a full load of 570 liters (150 gal) at temperatures greater than 38 degrees C.

Small crack test program for helicopter materials

NASA Technical Reports Server (NTRS)

Annigeri, Bal; Schneider, George

1994-01-01

Crack propagation tests were conducted to determine crack growth behavior in five helicopter materials for surface cracks between 0.005 to 0.020 inches in depth. Constant amplitude tests were conducted at stress ratios R equals 0.1 and 0.5, and emphasis was placed on near threshold data (i.e., 10-8 to 10-6 inches/cycle). Spectrum tests were conducted using a helicopter spectrum. The test specimen was an unnotched tension specimen, and cracks were initiated from a small EDM notch. An optical/video system was used to monitor crack growth. The material for the test specimens was obtained from helicopter part forgings. Testing was conducted at stresses below yield to reflect actual stresses in helicopter parts.

77 FR 69556 - Airworthiness Directives; Eurocopter Deutschland Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-20

..., 2011. (h) Subject Joint Aircraft Service Component (JASC) Code: 2436: DC Generator Control Unit. Issued... Deutschland GmbH (ECD) Model MBB-BK117 C-2 helicopters with certain Generator Control Units (GCU) installed... Ground Floor, Room W12- 140, 1200 New Jersey Avenue SE., Washington, DC 20590. FOR FURTHER INFORMATION...

VH-92A Presidential Helicopter (VH-92A)

DTIC Science & Technology

2015-12-01

HMX - 1) and support the President worldwide and the Vice President primarily inside the National Capital Region. Mission tasking encompasses two (2...Factor: 19% of Total Aircraft Inventory (TAI) Squadrons: Marine Helicopter Squadron One ( HMX -1) Helicopters per (active) squadron: 16 Monthly Flight

A NASTRAN investigation of simulated projectile damage effects on a UH-1B tail boom model

NASA Technical Reports Server (NTRS)

Futterer, A. T.

1980-01-01

A NASTRAN model of a UH-1B tail boom that had been designed for another project was used to investigate the effect on structural integrity of simulated projectile damage. Elements representing skin, and sections of stringers, longerons and bulkheads were systematically deleted to represent projectile damage. The structure was loaded in a manner to represent the flight loads that would be imposed on the tail boom at a 130 knot cruise. The deflection of four points on the rear of the tail boom relative to the position of these points for the unloaded, undamaged condition of the tail boom was used as a measure of the loss of structural rigidity. The same procedure was then used with the material properties of the aluminum alloys replaced with the material properties of T300/5208 high strength graphite/epoxy fibrous composite material, (0, + or - 45, 90)s for the skin and (0, + or - 45)s for the longerons, stringers, and bulk heads.

Investigation of difficult component effects on finite element model vibration prediction for the Bell AH-1G helicopter. Volume 1: Ground vibration test results

NASA Technical Reports Server (NTRS)

Dompka, R. V.

1989-01-01

Under the NASA-sponsored Design Analysis Methods for VIBrationS (DAMVIBS) program, a series of ground vibration tests and NASTRAN finite element model (FEM) correlations were conducted on the Bell AH-1G helicopter gunship to investigate the effects of difficult components on the vibration response of the airframe. Previous correlations of the AH-1G showed good agreement between NASTRAN and tests through 15 to 20 Hz, but poor agreement in the higher frequency range of 20 to 30 Hz. Thus, this effort emphasized the higher frequency airframe vibration response correlations and identified areas that need further R and T work. To conduct the investigations, selected difficult components (main rotor pylon, secondary structure, nonstructural doors/panels, landing gear, engine, fuel, etc.) were systematically removed to quantify their effects on overall vibratory response of the airframe. The entire effort was planned and documented, and the results reviewed by NASA and industry experts in order to ensure scientific control of the testing, analysis, and correlation exercise. In particular, secondary structure and damping had significant effects on the frequency response of the airframe above 15 Hz. Also, the nonlinear effects of thrust stiffening and elastomer mounts were significant on the low frequency pylon modes below main rotor 1p (5.4 Hz). The results of the ground vibration testing are presented.

Helicopter Crewseat Cushion Program

DTIC Science & Technology

1994-11-01

proportion of Army helicopter pilots suffer back pain caused by flying. Extended missions required during Desert Shield/Desert Storm emphasized this problem...Seat Cushions Lumbar Support Energy Absorbing Foam Lumbar Kyphosis 16. PRICE CODE Back Pain Thigh Support Helicopter Vibration Helicopter Seating _ 17...Bulging disks and stretched ligaments from lumbar kyphosis .................... 3 3 Measurement of anthropometric dimensions

Operational Testing of Software-Intensive Systems: Observations and Comments

DTIC Science & Technology

2011-03-01

Hood and Camp Bowie , Texas, October 16–December 8, 2006. This phase included an engineering company, an attack helicopter troop, and a battalion (-) of... Arnold . 2007a. Test data report for the Black Hawk Utility Helicopter (UH-60M) Initial Operational Test Phase IIa, Medical Evacuation Helicopter (HH...60M) Ex- cursion. U.S. Army Operational Test Command, Febru- ary 2007. Manning, W., J. B. Bush, C. Scott, and C. Arnold . 2007b. Test data report for

Optimization process in helicopter design

NASA Technical Reports Server (NTRS)

Logan, A. H.; Banerjee, D.

1984-01-01

In optimizing a helicopter configuration, Hughes Helicopters uses a program called Computer Aided Sizing of Helicopters (CASH), written and updated over the past ten years, and used as an important part of the preliminary design process of the AH-64. First, measures of effectiveness must be supplied to define the mission characteristics of the helicopter to be designed. Then CASH allows the designer to rapidly and automatically develop the basic size of the helicopter (or other rotorcraft) for the given mission. This enables the designer and management to assess the various tradeoffs and to quickly determine the optimum configuration.

NASA's Role in Aeronautics: A Workshop. Volume 7: Background papers

NASA Technical Reports Server (NTRS)

1981-01-01

The nature and implications of the current state of U.S. aviation in a world setting are examined as well as their significance for NASA's role in the nation's aeronautical future. The outlook for the 1980's is examined from the point of view of legislation, economics and finance; petroleum; manpower, metallic materials, general aviation; military aviation; transport aircraft developments; and helicopters. Possible NASA assistance to DOD and the FAA is examined and the evolution of NACA and NASA in aeronautics and of NASA's aeronautics capabilities are described.

Survivability on the Island of Spice: The Development of the UH-60 Blackhawk and Its Baptism of Fire in Operation Urgent Fury

DTIC Science & Technology

2015-06-12

SURVIVABILITY ON THE ISLAND OF SPICE : THE DEVELOPMENT OF THE UH-60 BLACKHAWK AND ITS BAPTISM OF FIRE IN OPERATION URGENT FURY......THESIS APPROVAL PAGE Name of Candidate: Major Matthew G. Easley Thesis Title: Survivability on the Island of Spice : The Development of the UH

Noise characteristics of eight helicopters

DOT National Transportation Integrated Search

1977-07-01

This report describes the noise characteristics of Eight Helicopters during level flyovers, simulated approaches, and hover. The data was obtained during an FAA/DOT Helicopter Noise Program to acquire a data base for possible helicopter noise regulat...

Prehospital helicopter transport and survival of patients with traumatic brain injury.

PubMed

Bekelis, Kimon; Missios, Symeon; Mackenzie, Todd A

2015-03-01

To investigate the association of helicopter transport with survival of patients with traumatic brain injury (TBI), in comparison with ground emergency medical services (EMS). Helicopter utilization and its effect on the outcomes of TBI remain controversial. We performed a retrospective cohort study involving patients with TBI who were registered in the National Trauma Data Bank between 2009 and 2011. Regression techniques with propensity score matching were used to investigate the association of helicopter transport with survival of patients with TBI, in comparison with ground EMS. During the study period, there were 209,529 patients with TBI who were registered in the National Trauma Data Bank and met the inclusion criteria. Of these patients, 35,334 were transported via helicopters and 174,195 via ground EMS. For patients transported to level I trauma centers, 2797 deaths (12%) were recorded after helicopter transport and 8161 (7.8%) after ground EMS. Multivariable logistic regression analysis demonstrated an association of helicopter transport with increased survival [OR (odds ratio), 1.95; 95% confidence interval (CI), 1.81-2.10; absolute risk reduction (ARR), 6.37%]. This persisted after propensity score matching (OR, 1.88; 95% CI, 1.74-2.03; ARR, 5.93%). For patients transported to level II trauma centers, 1282 deaths (10.6%) were recorded after helicopter transport and 5097 (7.3%) after ground EMS. Multivariable logistic regression analysis demonstrated an association of helicopter transport with increased survival (OR, 1.81; 95% CI, 1.64-2.00; ARR 5.17%). This again persisted after propensity score matching (OR, 1.73; 95% CI, 1.55-1.94; ARR, 4.69). Helicopter transport of patients with TBI to level I and II trauma centers was associated with improved survival, in comparison with ground EMS.

Prehospital Helicopter Transport and Survival of Patients With Traumatic Brain Injury

PubMed Central

Mackenzie, Todd A.

2015-01-01

Objective To investigate the association of helicopter transport with survival of patients with traumatic brain injury (TBI), in comparison with ground emergency medical services (EMS). Background Helicopter utilization and its effect on the outcomes of TBI remain controversial. Methods We performed a retrospective cohort study involving patients with TBI who were registered in the National Trauma Data Bank between 2009 and 2011. Regression techniques with propensity score matching were used to investigate the association of helicopter transport with survival of patients with TBI, in comparison with ground EMS. Results During the study period, there were 209,529 patients with TBI who were registered in the National Trauma Data Bank and met the inclusion criteria. Of these patients, 35,334 were transported via helicopters and 174,195 via ground EMS. For patients transported to level I trauma centers, 2797 deaths (12%) were recorded after helicopter transport and 8161 (7.8%) after ground EMS. Multivariable logistic regression analysis demonstrated an association of helicopter transport with increased survival [OR (odds ratio), 1.95; 95% confidence interval (CI), 1.81–2.10; absolute risk reduction (ARR), 6.37%]. This persisted after propensity score matching (OR, 1.88; 95% CI, 1.74–2.03; ARR, 5.93%). For patients transported to level II trauma centers, 1282 deaths (10.6%) were recorded after helicopter transport and 5097 (7.3%) after ground EMS. Multivariable logistic regression analysis demonstrated an association of helicopter transport with increased survival (OR, 1.81; 95% CI, 1.64–2.00; ARR 5.17%). This again persisted after propensity score matching (OR, 1.73; 95% CI, 1.55–1.94; ARR, 4.69). Conclusions Helicopter transport of patients with TBI to level I and II trauma centers was associated with improved survival, in comparison with ground EMS. PMID:24743624

Helicopter noise data : letter report DTS-75-FA053-LR8 (rev. 1)

DOT National Transportation Integrated Search

1990-07-17

One-third octave spectral noise data are provided for 15 helicopters from the TSC Helicopter Noise Data Library. The original data were measured by TSC in 1978 through 1983 and published in reports as listed below. The data have been adjusted to refe...

Blade Deflection Measurements of a Full-Scale UH-60A Rotor System

NASA Technical Reports Server (NTRS)

Olson, Lawrence E.; Abrego, Anita; Barrows, Danny A.; Burner, Alpheus W.

2010-01-01

Blade deflection (BD) measurements using stereo photogrammetry have been made during the individual blade control (IBC) testing of a UH-60A 4-bladed rotor system in the 40 by 80-foot test section of the National Full-Scale Aerodynamic Complex (NFAC). Measurements were made in quadrants one and two, encompassing advance ratios from 0.15 to 0.40, thrust coefficient/solidities from 0.05 to 0.12 and rotor-system drive shaft angles from 0.0 to -9.6 deg. The experiment represents a significant step toward providing benchmark databases to be utilized by theoreticians in the development and validation of rotorcraft prediction techniques. In addition to describing the stereo measurement technique and reporting on preliminary measurements made to date, the intent of this paper is to encourage feedback from the rotorcraft community concerning continued analysis of acquired data and to solicit suggestions for improved test technique and areas of emphasis for measurements in the upcoming UH-60A Airloads test at the NFAC.

Design and flight evaluation of an integrated navigation and near-terrain helicopter guidance system for night-time and adverse weather operations

NASA Technical Reports Server (NTRS)

Swenson, Harry N.; Zelenka, Richard E.; Dearing, Munro G.; Hardy, Gordon H.; Clark, Raymond; Davis, Tom; Amatrudo, Gary; Zirkler, Andre

1994-01-01

NASA and the U.S. Army have designed, developed, and flight evaluated a Computer Aiding for Low Altitude Helicopter Flight (CALAHF) guidance system. This system provides guidance to the pilot for near terrain covert helicopter operations. It automates the processing of precision navigation information, helicopter mission requirements, and terrain flight guidance. The automation is presented to the pilot through symbology on a helmet-mounted display. The symbology is a 'pilot-centered' design which preserves pilot flexibility and authority over the CALAHF system's automation. An extensive flight evaluation of the system has been conducted using the U.S. Army's NUH-60 STAR (Systems Testbed for Avionics Research) research helicopter. The evaluations were flown over a multiwaypoint helicopter mission in rugged mountainous terrain, at terrain clearance altitudes from 300 to 125 ft and airspeeds from 40 to 110 knots. The results of these evaluations showed that the pilots could precisely follow the automation symbology while maintaining a high degree of situational awareness.

Helicopter Northeast Corridor Operational Test Support.

DTIC Science & Technology

1980-06-01

helicopters in the U. S. and Canada show a predom- inent application of small helicopters COMMERCIAL USES OF SMALL AND MEDIUM for corporate, charter, aerial...appli- HEICOPTERS cations and public safety. Medium/ U.S. and Canada. Exolessedin oercent. Small Medium heavy helicopters are used predomi- Use...safety (police. lire 17.5 4.0 fighting. etc. LTraining 6.0 - Figure 5 GROWTH FORECAST FOR SMALL AND MEDIUM HELICOPTERS For U.S. and Canada. Helicopter

Piloted simulator investigation of helicopter control systems effects on handling qualities during instrument flight

NASA Technical Reports Server (NTRS)

Forrest, R. D.; Chen, R. T. N.; Gerdes, R. M.; Alderete, T. S.; Gee, D. R.

1979-01-01

An exploratory piloted simulation was conducted to investigate the effects of the characteristics of helicopter flight control systems on instrument flight handling qualities. This joint FAA/NASA study was motivated by the need to improve instrument flight capability. A near-term objective is to assist in updating the airworthiness criteria for helicopter instrument flight. The experiment consisted of variations of single-rotor helicopter types and levels of stability and control augmentation systems (SCAS). These configurations were evaluated during an omnirange approach task under visual and instrument flight conditions. The levels of SCAS design included a simple rate damping system, collective decoupling plus rate damping, and an attitude command system with collective decoupling. A limited evaluation of stick force versus airspeed stability was accomplished. Some problems were experienced with control system mechanization which had a detrimental effect on longitudinal stability. Pilot ratings, pilot commentary, and performance data related to the task are presented.

Full-Scale Crash Test and Finite Element Simulation of a Composite Prototype Helicopter

NASA Technical Reports Server (NTRS)

Jackson, Karen E.; Fasanella, Edwin L.; Boitnott, Richard L.; Lyle, Karen H.

2003-01-01

A full-scale crash test of a prototype composite helicopter was performed at the Impact Dynamics Research Facility at NASA Langley Research Center in 1999 to obtain data for validation of a finite element crash simulation. The helicopter was the flight test article built by Sikorsky Aircraft during the Advanced Composite Airframe Program (ACAP). The composite helicopter was designed to meet the stringent Military Standard (MIL-STD-1290A) crashworthiness criteria and was outfitted with two crew and two troop seats and four anthropomorphic dummies. The test was performed at 38-ft/s vertical and 32.5-ft/s horizontal velocity onto a rigid surface. An existing modal-vibration model of the Sikorsky ACAP helicopter was converted into a model suitable for crash simulation. A two-stage modeling approach was implemented and an external user-defined subroutine was developed to represent the complex landing gear response. The crash simulation was executed with a nonlinear, explicit transient dynamic finite element code. Predictions of structural deformation and failure, the sequence of events, and the dynamic response of the airframe structure were generated and the numerical results were correlated with the experimental data to validate the simulation. The test results, the model development, and the test-analysis correlation are described.

46 CFR 108.653 - Helicopter facilities.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Helicopter facilities. 108.653 Section 108.653 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.653 Helicopter facilities. (a) Each helicopter fueling facility must be marked adjacent to the fueling hose storage: “WARNING—HELICOPTER FUELING STATION—KEEP...

46 CFR 108.653 - Helicopter facilities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Helicopter facilities. 108.653 Section 108.653 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.653 Helicopter facilities. (a) Each helicopter fueling facility must be marked adjacent to the fueling hose storage: “WARNING—HELICOPTER FUELING STATION—KEEP...

46 CFR 108.653 - Helicopter facilities.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Helicopter facilities. 108.653 Section 108.653 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.653 Helicopter facilities. (a) Each helicopter fueling facility must be marked adjacent to the fueling hose storage: “WARNING—HELICOPTER FUELING STATION—KEEP...

46 CFR 108.653 - Helicopter facilities.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Helicopter facilities. 108.653 Section 108.653 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.653 Helicopter facilities. (a) Each helicopter fueling facility must be marked adjacent to the fueling hose storage: “WARNING—HELICOPTER FUELING STATION—KEEP...

46 CFR 108.653 - Helicopter facilities.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Helicopter facilities. 108.653 Section 108.653 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.653 Helicopter facilities. (a) Each helicopter fueling facility must be marked adjacent to the fueling hose storage: “WARNING—HELICOPTER FUELING STATION—KEEP...

Gulf of Mexico Helicopter Offshore System Technologies Recommended Development Path

NASA Technical Reports Server (NTRS)

Koenke, Edmund J.; Williams, Larry; Calafa, Caesar

1999-01-01

The National Aeronautics and Space Administration (NASA) Advanced Air Transportation Technologies (AATT) project in cooperation with the Department of Transportation (DOT) Volpe National Transportation Systems Center (VNTSC) contracted with the System Resources Corporation (SRC) for the evaluation of the existing environment and the identification of user and service provider needs in the Gulf of Mexico low-altitude Offshore Sector. The results of this contractor activity are reported in the Gulf of Mexico Helicopter Offshore System Technologies Engineering Needs Assessment. A recommended system design and transition strategy was then developed to satisfy the identified needs within the constraints of the environment. This work, also performed under contract to NASA, is the subject of this report.

Investigation of the effects of bandwidth and time delay on helicopter roll-axis handling qualities

NASA Technical Reports Server (NTRS)

Pausder, Heinz-Juergen; Blanken, Chris L.

1992-01-01

Several years of cooperative research conducted under the U.S./German Memorandum of Understanding (MOU) in helicopter flight control has recently resulted in a successful handling qualities study. The focus of this cooperative research has been the effects on handling qualities due to time delays in combination with a high bandwidth vehicle. The jointly performed study included the use of U.S. ground-based simulation and German in-flight simulation facilities. The NASA-Ames Vertical Motion Simulator (VMS) was used to develop a high bandwidth slalom tracking task which took into consideration the constraints of the facilities. The VMS was also used to define a range of the test parameters and to perform initial handling qualities evaluations. The flight tests were conducted using DLR's variable-stability BO 105 S3 Advanced Technology Testing Helicopter System (ATTHeS). Configurations included a rate command and an attitude command response system with added time delays up to 160 milliseconds over the baseline and bandwidth values between 1.5 and 4.5 rad/sec. Sixty-six evaluations were performed in about 25 hr of flight time during 10 days of testing. The results indicate a need to more tightly constrain the allowable roll axis phase delay for the Level 1 and Level 2 requirements in the U.S. Army's specification for helicopter handling qualities, ADS-33C.

Investigation of the effects of bandwidth and time delay on helicopter roll-axis handling qualities

NASA Technical Reports Server (NTRS)

Blanken, Chris L.; Pausder, Heinz-Jurgen

1994-01-01

Several years of cooperative research conducted under the U.S./German Memorandum of Understanding (MOU) in helicopter aeromechanics have recently resulted in a successful handling qualities study. The focus of this cooperative research has been the effect of time delays in a high bandwidth vehicle on handling qualities. The jointly performed study included the use of U.S. ground-based simulation and German in-flight simulation facilities. The NASA-Ames Vertical Motion Simulator (VMS) was used to develop a high bandwidth slalom tracking task which took into consideration the constraints of the facilities. The VMS was used to define a range of the test parameters and to perform initial handling qualities evaluations. The flight tests were conducted using DLR's variable-stability BO 105 S3 Advanced Technology Testing Helicopter System (ATTHeS). Configurations included a rate command and an attitude command response system with added time delays of up to 160 milliseconds over the baseline and band width values between 1.5 and 4.5 rad/sec. Sixty-six evaluations were performed in about 25 hours of flight time during ten days of testing. The results indicate a need to more tightly constrain the allowable roll axis phase delay for the Level 1 and Level 2 requirements in the U.S. Army's specification for helicopter handling qualities Aeronautical Design Standard (ADS)-33C.

Investigation of the effects of bandwidth and time delay on helicopter roll-axis handling qualities

NASA Technical Reports Server (NTRS)

Pausder, Heinz-Juergen; Blanken, Chris L.

1993-01-01

Several years of cooperative research conducted under the U.S./German Memorandum of Understanding (MOU) in helicopter flight control has recently resulted in a successful handling qualities study. The focus of this cooperative research has been the effects on handling qualities due to time delays in combination with a high bandwidth vehicle. The jointly performed study included the use of U.S. ground-based simulation and German in-flight simulation facilities. The NASA-Ames Vertical Motion Simulator (VMS) was used to develop a high bandwidth slalom tracking task which took into consideration the constraints of the facilities. The VMS was also used to define a range of the test parameters and to perform initial handling qualities evaluations. The flight tests were conducted using DLR's variable-stability BO 105 S3 Advanced Technology Testing Helicopter System (ATTHeS). Configurations included a rate command and an attitude command response system with added time delays up to 160 milliseconds over the baseline and bandwidth values between 1.5 and 4.5 rad/sec. Sixty-six evaluations were performed in about 25 hours of flight time during ten days of testing. The results indicate a need to more tightly constrain the allowable roll axis phase delay for the Level 1 and Level 2 requirements in the U.S. Army's specification for helicopter handling qualities, ADS-33C.

Development of Novel Methods for the Reduction of Noise and Weight in Helicopter Transmissions

NASA Technical Reports Server (NTRS)

Dimofte, Florin; Keith, Theo G., Jr.

2003-01-01

Over the 70-year evolution of the helicopter, man's understanding of vibration control has greatly increased. However, in spite of the increased performance, the extent of helicopter vibration problems has not significantly diminished. Crew vibration and noise remains important factors in the design of all current helicopters. With more complex and critical demands being placed on aircrews, it is essential that vibration and noise not impair their performance. A major source of helicopter cabin noise (which has been measured at a sound pressure level of over 100 dB) is the gearbox. Reduction of this noise has been a goal of NASA and the U.S. Army. Gear mesh noise is typically in the frequency range of 1000 to 3000 Hz, a range important for speech. A requirement for U.S. Army/NASA Advanced Rotorcraft Transmission project has been a 10-dB reduction compared to current designs. A combined analytical/experimental effort has been underway, since the end of the 80's, to study effects of design parameters on noise production. The noise generated by the gear mesh can be transmitted to the surrounding media through the bearings that support the gear shaft. Therefore, the use of fluid film bearings instead of rolling element bearings could reduce the transmission noise by 10 dB. In addition, the fluid film bearings that support the gear shaft can change the dynamics of the gear assembly by providing damping to the system and by being softer than rolling element bearings. Wave bearings can attenuate, and filter, the noise generated by a machine component due to the dynamic stiffness and damping coefficients. The attenuation ratio could be as large as 35-40 dB. The noise components at higher frequencies than a synchronous frequency can be almost eliminated.

75 FR 62639 - Air Ambulance and Commercial Helicopter Operations, Part 91 Helicopter Operations, and Part 135...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-12

...This proposed rule addresses air ambulance and commercial helicopter operations, part 91 helicopter operations, and load manifest requirements for all part 135 aircraft. From 2002 to 2008, there has been an increase in fatal helicopter air ambulance accidents. To address these safety concerns, the FAA is proposing to implement operational procedures and require additional equipment on board helicopter air ambulances. Many of these proposed requirements currently are found in agency guidance publications and would address National Transportation Safety Board (NTSB) safety recommendations. Some of these safety concerns are not unique to the helicopter air ambulance industry and affect all commercial helicopter operations. Accordingly, the FAA also is proposing to amend regulations pertaining to all commercial helicopter operations conducted under part 135 to include equipment requirements, pilot training, and alternate airport weather minima. The changes are intended to provide certificate holders and pilots with additional tools and procedures that will aid in preventing accidents.

46 CFR 108.486 - Helicopter decks.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the unit's...

46 CFR 108.486 - Helicopter decks.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the unit's...

46 CFR 108.486 - Helicopter decks.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the unit's...

46 CFR 108.486 - Helicopter decks.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the unit's...

46 CFR 108.486 - Helicopter decks.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the unit's...

NDARC NASA Design and Analysis of Rotorcraft Theory Appendix 1

NASA Technical Reports Server (NTRS)

Johnson, Wayne

2016-01-01

The NASA Design and Analysis of Rotorcraft (NDARC) software is an aircraft system analysis tool that supports both conceptual design efforts and technology impact assessments. The principal tasks are to design (or size) a rotorcraft to meet specified requirements, including vertical takeoff and landing (VTOL) operation, and then analyze the performance of the aircraft for a set of conditions. For broad and lasting utility, it is important that the code have the capability to model general rotorcraft configurations, and estimate the performance and weights of advanced rotor concepts. The architecture of the NDARC code accommodates configuration flexibility, a hierarchy of models, and ultimately multidisciplinary design, analysis, and optimization. Initially the software is implemented with low-fidelity models, typically appropriate for the conceptual design environment. An NDARC job consists of one or more cases, each case optionally performing design and analysis tasks. The design task involves sizing the rotorcraft to satisfy specified design conditions and missions. The analysis tasks can include off-design mission performance calculation, flight performance calculation for point operating conditions, and generation of subsystem or component performance maps. For analysis tasks, the aircraft description can come from the sizing task, from a previous case or a previous NDARC job, or be independently generated (typically the description of an existing aircraft). The aircraft consists of a set of components, including fuselage, rotors, wings, tails, and propulsion. For each component, attributes such as performance, drag, and weight can be calculated; and the aircraft attributes are obtained from the sum of the component attributes. Description and analysis of conventional rotorcraft configurations is facilitated, while retaining the capability to model novel and advanced concepts. Specific rotorcraft configurations considered are single-main-rotor and tail

3D-LZ helicopter ladar imaging system

NASA Astrophysics Data System (ADS)

Savage, James; Harrington, Walter; McKinley, R. Andrew; Burns, H. N.; Braddom, Steven; Szoboszlay, Zoltan

2010-04-01

A joint-service team led by the Air Force Research Laboratory's Munitions and Sensors Directorates completed a successful flight test demonstration of the 3D-LZ Helicopter LADAR Imaging System. This was a milestone demonstration in the development of technology solutions for a problem known as "helicopter brownout", the loss of situational awareness caused by swirling sand during approach and landing. The 3D-LZ LADAR was developed by H.N. Burns Engineering and integrated with the US Army Aeroflightdynamics Directorate's Brown-Out Symbology System aircraft state symbology aboard a US Army EH-60 Black Hawk helicopter. The combination of these systems provided an integrated degraded visual environment landing solution with landing zone situational awareness as well as aircraft guidance and obstacle avoidance information. Pilots from the U.S. Army, Air Force, Navy, and Marine Corps achieved a 77% landing rate in full brownout conditions at a test range at Yuma Proving Ground, Arizona. This paper will focus on the LADAR technology used in 3D-LZ and the results of this milestone demonstration.

76 FR 10489 - Special Conditions: Bell Helicopter Textron Canada Limited Model 407 Helicopter, Installation of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-25

... non-critical control functions, since this model helicopter has been certificated to meet the... Canada Limited (Bell) model 407 helicopter. This model helicopter will have novel or unusual design..., Rotorcraft Directorate, Regulations and Policy Group (ASW-111), 2601 Meacham Blvd., Fort Worth, Texas 76137...

Helicopter problems

NASA Technical Reports Server (NTRS)

Kussner, H G

1937-01-01

The present report deals with a number of the main problems requiring solution in the development of helicopters and concerning the lift, flying performance, stability, and drive. A complete solution is given for the stability of the helicopter with rigid blades and control surfaces. With a view to making a direct-lift propeller sufficient without the addition of auxiliary propellers, the "flapping drive" is assessed and its efficiency calculated.

Planning, creating and documenting a NASTRAN finite element model of a modern helicopter

NASA Technical Reports Server (NTRS)

Gabal, R.; Reed, D.; Ricks, R.; Kesack, W.

1985-01-01

Mathematical models based on the finite element method of structural analysis as embodied in the NASTRAN computer code are widely used by the helicopter industry to calculate static internal loads and vibration of airframe structure. The internal loads are routinely used for sizing structural members. The vibration predictions are not yet relied on during design. NASA's Langley Research Center sponsored a program to conduct an application of the finite element method with emphasis on predicting structural vibration. The Army/Boeing CH-47D helicopter was used as the modeling subject. The objective was to engender the needed trust in vibration predictions using these models and establish a body of modeling guides which would enable confident future prediction of airframe vibration as part of the regular design process.

Simulation evaluation of a low-altitude helicopter flight guidance system adapted for a helmet-mounted display

NASA Technical Reports Server (NTRS)

Swenson, Harry N.; Zelenka, Richard E.; Hardy, Gordon H.; Dearing, Munro G.

1992-01-01

A computer aiding concept for low-altitude helicopter flight was developed and evaluated in a real-time piloted simulation. The concept included an optimal control trajectory-generation algorithm based upon dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and advanced navigation information to determine a trajectory between mission way points that seeks valleys to minimize threat exposure. The pilot evaluation was conducted at NASA ARC moving base Vertical Motion Simulator (VMS) by pilots representing NASA, the U.S. Army, the Air Force, and the helicopter industry. The pilots manually tracked the trajectory generated by the algorithm utilizing the HMD symbology. The pilots were able to satisfactorily perform the tracking tasks while maintaining a high degree of awareness of the outside world.

Study of Cost/Benefit Tradeoffs Available in Helicopter Noise Technology Applications

DTIC Science & Technology

1980-01-01

Report No. FAA-EE-80-5 .,,-vx s?Pi iO Oi CO 00 o STUDY OF COST/ BENEFIT TRADEOFFS AVAILABLE IN HELICOPTER NOISE TECHNOLOGY APPLICATIONS R.H...Documentation Page ). Report No. FAA-EE-80-5 2. Government Accession No. i. Title ord Subtitle Study of Cost/ Benefit Tradeoffs Available in...Abstract This study investigated cost/ benefit tradeoffs using the case histories of four helicopters for which design and development were complete, and in

Helicopter roll control effectiveness criteria program summary

NASA Technical Reports Server (NTRS)

Heffley, Robert K.; Bourne, Simon M.; Mnich, Marc A.

1988-01-01

A study of helicopter roll control effectiveness is summarized for the purpose of defining military helicopter handling qualities requirements. The study is based on an analysis of pilot-in-the-loop task performance of several basic maneuvers. This is extended by a series of piloted simulations using the NASA Ames Vertical Motion Simulator and selected flight data. The main results cover roll control power and short-term response characteristics. In general the handling qualities requirements recommended are set in conjunction with desired levels of flight task and maneuver response which can be directly observed in actual flight. An important aspect of this, however, is that vehicle handling qualities need to be set with regard to some quantitative aspect of mission performance. Specific examples of how this can be accomplished include a lateral unmask/remask maneuver in the presence of a threat and an air tracking maneuver which recognizes the kill probability enhancement connected with decreasing the range to the target. Conclusions and recommendations address not only the handling qualities recommendations, but also the general use of flight simulators and the dependence of mission performance on handling qualities.

Design, manufacture and spin test of high contact ratio helicopter transmission utilizing Self-Aligning Bearingless Planetary (SABP)

NASA Technical Reports Server (NTRS)

Folenta, Dezi; Lebo, William

1988-01-01

A 450 hp high ratio Self-Aligning Bearingless Planetary (SABP) for a helicopter application was designed, manufactured, and spin tested under NASA contract NAS3-24539. The objective of the program was to conduct research and development work on a high contact ratio helical gear SABP to reduce weight and noise and to improve efficiency. The results accomplished include the design, manufacturing, and no-load spin testing of two prototype helicopter transmissions, rated at 450 hp with an input speed of 35,000 rpm and an output speed of 350 rpm. The weight power density ratio of these gear units is 0.33 lb hp. The measured airborne noise at 35,000 rpm input speed and light load is 94 dB at 5 ft. The high speed, high contact ratio SABP transmission appears to be significantly lighter and quieter than comtemporary helicopter transmissions. The concept of the SABP is applicable not only to high ratio helicopter type transmissions but also to other rotorcraft and aircraft propulsion systems.

Low back pain in Norwegian helicopter aircrew.

PubMed

Hansen, O B; Wagstaff, A S

2001-03-01

The size and consequences of low back pain (LBP) in Norwegian helicopter aircrew has been investigated in a retrospective and prospective survey. With 50.5% reporting such pain in a 2-yr period, and Sea King aircrew reporting LBP on on almost half (49.3%) of the missions flown, the magnitude of the problem equals that reported from other air forces. Pilots reported LBP six times more often than other crewmembers and almost half (48.6%) felt the pain influenced the quality of work. This could have flight safety implications. Crewmembers with total flying time over 2,000 h have a significantly higher incidence of sick leave than those with less than 2,000 h. Only 1 pilot out of 10 with total flying time under 500 h had had flight-related LBP.

Department of Defense In-House RDT&E Activities

DTIC Science & Technology

1981-10-30

DISEASES*.’......*......... 43 MISSILE LABORATORY ................................................. 44 MOBILITY EQUIPMENT R&D COMMAND...HELICOPTER INFLIGHT MONITORING SYS WITH INSTRUMENTED RANGE; ANECHOIC AND REVERBERATION CHAMBERS; MOBILE -’ ACCOUSTICS LAB; EYE MOVEMENT MEASURING...IN- CLUDES: LIGHTWEIGIHT OPTICAL TRACKING SYSTEM, 25-TON CRANE, 2 20-TON MOBILE CRANES, 5-TON WRECKER, 40,000 LB ACFT LOADER, THREE T-28B ACFT, 1 UH

Wind tunnel investigation of helicopter-rotor wake effects on three helicopter fuselage models

NASA Technical Reports Server (NTRS)

Wilson, J. C.; Mineck, R. E.

1975-01-01

The effects of rotor wake on helicopter fuselage aerodynamic characteristics were investigated in the Langley V/STOL tunnel. Force, moment, and pressure data were obtained on three fuselage models at various combinations of windspeed, sideslip angle, and pitch angle. The data show that the influence of rotor wake on the helicopter fuselage yawing moment imposes a significant additional thrust requirement on the tail rotor of a single-rotor helicopter at high sideslip angles.

Refinement and evaluation of helicopter real-time self-adaptive active vibration controller algorithms

NASA Technical Reports Server (NTRS)

Davis, M. W.

1984-01-01

A Real-Time Self-Adaptive (RTSA) active vibration controller was used as the framework in developing a computer program for a generic controller that can be used to alleviate helicopter vibration. Based upon on-line identification of system parameters, the generic controller minimizes vibration in the fuselage by closed-loop implementation of higher harmonic control in the main rotor system. The new generic controller incorporates a set of improved algorithms that gives the capability to readily define many different configurations by selecting one of three different controller types (deterministic, cautious, and dual), one of two linear system models (local and global), and one or more of several methods of applying limits on control inputs (external and/or internal limits on higher harmonic pitch amplitude and rate). A helicopter rotor simulation analysis was used to evaluate the algorithms associated with the alternative controller types as applied to the four-bladed H-34 rotor mounted on the NASA Ames Rotor Test Apparatus (RTA) which represents the fuselage. After proper tuning all three controllers provide more effective vibration reduction and converge more quickly and smoothly with smaller control inputs than the initial RTSA controller (deterministic with external pitch-rate limiting). It is demonstrated that internal limiting of the control inputs a significantly improves the overall performance of the deterministic controller.

Preliminary Results Obtained in Integrated Safety Analysis of NASA Aviation Safety Program Technologies

NASA Technical Reports Server (NTRS)

2001-01-01

This is a listing of recent unclassified RTO technical publications processed by the NASA Center for AeroSpace Information from January 1, 2001 through March 31, 2001 available on the NASA Aeronautics and Space Database. Contents include 1) Cognitive Task Analysis; 2) RTO Educational Notes; 3) The Capability of Virtual Reality to Meet Military Requirements; 4) Aging Engines, Avionics, Subsystems and Helicopters; 5) RTO Meeting Proceedings; 6) RTO Technical Reports; 7) Low Grazing Angle Clutter...; 8) Verification and Validation Data for Computational Unsteady Aerodynamics; 9) Space Observation Technology; 10) The Human Factor in System Reliability...; 11) Flight Control Design...; 12) Commercial Off-the-Shelf Products in Defense Applications.

Helicopter use in rural trauma.

PubMed

Shepherd, Matthew Vincent; Trethewy, Christopher Ernest; Kennedy, John; Davis, Lin

2008-12-01

To profile a helicopter emergency medical service in rural Australia. To assess patient injury severities and outcomes. To compare missions involving ambulance officers with physicians. To determine any time advantage of the aircraft over ground transfer. Intention-to-treat analysis using retrospective case note review of all helicopter emergency medical service trauma patients from January 2004 to November 2006. Global positioning system mapping technology was used to compare one-way road transfer times with two-way helicopter retrieval. Two hundred and twenty-two missions were identified from the helicopter log. Forty missions were aborted in flight. Of 182 patients transported, 11 records were incomplete, leaving 171 for analysis. Fifty (29%) patients transported had an Injury Severity Score (ISS) > 15; the average ISS was 12.30 (standard error of the mean 0.82). The average calculated distance flown was 160.4 nautical miles (standard error of the mean 5.29; range 28-360 nautical miles). There was no significant difference in ISS between ambulance officers and physician groups (t = -1.17, P = 0.25, 95% CI -7.37-1.91). There was no difference in the incidence of severe injury (ISS > 15, P = 0.39) or mortality (P = 0.33) when the groups were compared. Air transport was significantly faster beyond 100 km, with a mean difference of 48 min (P = 0.00). We could not identify a significant survival benefit attributable to the addition of a doctor, although numbers for this comparison were small. Predicting missions where flight physicians might provide benefit remain imprecise and should be a priority area for prospective evaluation. We have demonstrated that in the absence of special circumstances, a helicopter response within 100 km from base does not improve time to definitive care.

78 FR 23698 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-22

... fire extinguisher discharge tube (No. 1 engine tube). This proposed AD is prompted by the discovery that the No. 1 engine tube installed on the helicopters is too long to ensure that a fire could be effectively extinguished on a helicopter. The proposed actions are intended to ensure the No. 1 engine tube...

77 FR 52270 - Airworthiness Directives; Agusta S.p.A. Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-29

... would take about three work- hours per helicopter to rework the top cable-cutter assembly, one work... would be $255 per helicopter to rework the top cable-cutter assembly, $9,085 per helicopter to replace... 4G9540A00111, either: (i) Rework the top cable cutter assembly, P/N 423-83001-1, in accordance with the...

NASA/Army Rotorcraft Transmission Research, a Review of Recent Significant Accomplishments

NASA Technical Reports Server (NTRS)

Krantz, Timothy L.

1994-01-01

A joint helicopter transmission research program between NASA Lewis Research Center and the U.S. Army Research Lab has existed since 1970. Research goals are to reduce weight and noise while increasing life, reliability, and safety. These research goals are achieved by the NASA/Army Mechanical Systems Technology Branch through both in-house research and cooperative research projects with university and industry partners. Some recent significant technical accomplishments produced by this cooperative research are reviewed. The following research projects are reviewed: oil-off survivability of tapered roller bearings, design and evaluation of high contact ratio gearing, finite element analysis of spiral bevel gears, computer numerical control grinding of spiral bevel gears, gear dynamics code validation, computer program for life and reliability of helicopter transmissions, planetary gear train efficiency study, and the Advanced Rotorcraft Transmission (ART) program.

78 FR 23114 - Airworthiness Directives; Bell Helicopter Textron Canada (Bell) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-18

...) and in the AFCS [Automatic Flight Control System] Air Data Computer.'' TCAA issued AD CF-2005-30 to... Bell Model 430 helicopters, which requires replacing certain components of the air data system. This AD... helicopters. That NPRM proposed to require replacing certain components of the air data system. The proposed...

77 FR 31172 - Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-25

... control of the helicopter. Transport Canada (TC), which is the aviation authority for Canada, issued... BHTC Model 427 helicopters, serial numbers (S/Ns) 56001 through 56084, and S/Ns 58001 and 58002. TC..., TC, its technical representative, has notified us of the unsafe condition described in the TC AD. We...

78 FR 49116 - Airworthiness Directives; Eurocopter France Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-13

..., B2, B3, BA, C, D, and D1 helicopters; and Model AS355E, F, F1, F2, N, and NP helicopters. The... certain Eurocopter Model AS350B, B1, B2, B3, BA, C, D, and D1 and Model AS355E, F, F1, F2, N, and NP... pilot if certain regulatory recordkeeping requirements are met. As such, AD 2011-22-05 currently...

ARC-2003-ACD03-0112-050

NASA Image and Video Library

2003-09-05

NRTC/RITA Precision Pathway Terminal Guidance: UH-60 RASCAL (#012) (National Rotocraft Technology Center/Rotorcraft Industry Technology Association) runway independent aircraft; Sikorsky Helicopter pilot Kevin Bredenbeck preparing for flight in RASCAL with Dave Arterburn

ARC-2003-ACD03-0112-046

NASA Image and Video Library

2003-09-05

NRTC/RITA Precision Pathway Terminal Guidance: UH-60 RASCAL (#012) (National Rotocraft Technology Center/Rotorcraft Industry Technology Association) runway independent aircraft - Sikorsky Helicopter pilot Kevin Bredenbeck preparing for flight in RASCAL with Dave Arterburn

ARC-2003-ACD03-0112-044

NASA Image and Video Library

2003-09-05

NRTC/RITA Precision Pathway Terminal Guidance: UH-60 RASCAL (#012) (National Rotocraft Technology Center/Rotorcraft Industry Technology Association) runway independent aircraft - Sikorsky Helicopter pilot Kevin Bredenbeck preparing for flight in RASCAL with Dave Arterburn

ARC-2003-ACD03-0112-047

NASA Image and Video Library

2003-09-05

NRTC/RITA Precision Pathway Terminal Guidance: UH-60 RASCAL (#012) (National Rotocraft Technology Center/Rotorcraft Industry Technology Association) runway independent aircraft - Sikorsky Helicopter pilot Kevin Bredenbeck with Dave Arterburn and Ernie Morales of Ames

ARC-2003-ACD03-0112-048

NASA Image and Video Library

2003-09-05

NRTC/RITA Precision Pathway Terminal Guidance: UH-60 RASCAL (#012) (National Rotocraft Technology Center/Rotorcraft Industry Technology Association) runway independent aircraft - Sikorsky Helicopter pilot Kevin Bredenbeck with Dave Arterburn and Ernie Morales of Ames

Helicopter simulator qualification

NASA Technical Reports Server (NTRS)

Hampson, Brian

1992-01-01

CAE has extensive experience in building helicopter simulators and has participated in group working sessions for fixed-wing advisory circulars. Against this background, issues that should be addressed in establishing helicopter approval criteria were highlighted. Some of these issues are not immediately obvious and may, indeed, be more important than the criteria a themselves.

Application of Neural Networks to Predict UH-60L Electrical Generator Condition using (IMD-HUMS) Data

DTIC Science & Technology

2006-12-01

Data transfer unit ( DTU ) • Remote data concentrator (RDC) • Main processor unit (MPU) • 2 junction boxes (JB1/JB2) • 20 drive train and...NETWORKS TO PREDICT UH-60L ELECTRICAL GENERATOR CONDITION USING (IMD-HUMS) DATA by Evangelos Tourvalis December 2006 Thesis Advisor...including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the

Correlating CFD Simulation with Wind Tunnel Test for the Full-Scale UH-60A Airloads Rotor

NASA Technical Reports Server (NTRS)

Romandr, Ethan; Norman, Thomas R.; Chang, I-Chung

2011-01-01

Data from the recent UH-60A Airloads Test in the National Full-Scale Aerodynamics Complex 40- by 80- Foot Wind Tunnel at NASA Ames Research Center are presented and compared to predictions computed by a loosely coupled Computational Fluid Dynamics (CFD)/Comprehensive analysis. Primary calculations model the rotor in free-air, but initial calculations are presented including a model of the tunnel test section. The conditions studied include a speed sweep at constant lift up to an advance ratio of 0.4 and a thrust sweep at constant speed into deep stall. Predictions show reasonable agreement with measurement for integrated performance indicators such as power and propulsive but occasionally deviate significantly. Detailed analysis of sectional airloads reveals good correlation in overall trends for normal force and pitching moment but pitching moment mean often differs. Chord force is frequently plagued by mean shifts and an overprediction of drag on the advancing side. Locations of significant aerodynamic phenomena are predicted accurately although the magnitude of individual events is often missed.

Airloads Correlation of the UH-60A Rotor Inside the 40- by 80-Foot Wind Tunnel

NASA Technical Reports Server (NTRS)

Chang, I-Chung; Norman, Thomas R.; Romander, Ethan A.

2013-01-01

The presented research validates the capability of a loosely-coupled computational fluid dynamics (CFD) and comprehensive rotorcraft analysis (CRA) code to calculate the flowfield around a rotor and test stand mounted inside a wind tunnel. The CFD/CRA predictions for the full-scale UH-60A Airloads Rotor inside the National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Foot Wind Tunnel at NASA Ames Research Center are compared with the latest measured airloads and performance data. The studied conditions include a speed sweep at constant lift up to an advance ratio of 0.4 and a thrust sweep at constant speed up to and including stall. For the speed sweep, wind tunnel modeling becomes important at advance ratios greater than 0.37 and test stand modeling becomes increasingly important as the advance ratio increases. For the thrust sweep, both the wind tunnel and test stand modeling become important as the rotor approaches stall. Despite the beneficial effects of modeling the wind tunnel and test stand, the new models do not completely resolve the current airload discrepancies between prediction and experiment.

Equipment for pre-hospital airway management on Helicopter Emergency Medical System helicopters in central Europe.

PubMed

Schmid, M; Schüttler, J; Ey, K; Reichenbach, M; Trimmel, H; Mang, H

2011-05-01

For advanced out-of-hospital airway management, skilled personnel and adequate equipment are key prerequisites. There are little data on the current availability of airway management equipment and standards of medical staff on Helicopter Emergency Medical System (HEMS) helicopters in central Europe. An internet search identified all HEMS helicopters in Austria, Switzerland and Luxembourg. We identified 15 HEMS helicopter bases in Switzerland, 28 in Austria and three in Luxembourg. A questionnaire was sent to all bases, asking both for the details of the clinical background and experience of participating staff, and details of airway management equipment carried routinely on board. Replies were received from 14 helicopter bases in Switzerland (93%), 25 bases in Austria (89%) and all three bases in Luxembourg. Anaesthesiologists were by far the most frequent attending physicians (68-85%). All except one bases reported to have at least one alternative supraglottic airway device. All bases had capnometry and succinylcholine. All bases in the study except two in Austria had commercial pre-packed sets for a surgical airway. All helicopters were equipped with automatic ventilators, although not all were suitable for non-invasive ventilation (NIV; Switzerland: 43%, Austria: 12%, Luxembourg: 100%). Masks for NIV were rarely available in Switzerland (two bases; 14%) and in Austria (three bases; 12%), whereas all three bases in Luxembourg carried those masks. Most HEMS helicopters carry appropriate equipment to meet the demands of modern advanced airway management in the pre-hospital setting. Further work is needed to ensure that appropriate airway equipment is carried on all HEMS helicopters.

Spectral decontamination of a real-time helicopter simulation

NASA Technical Reports Server (NTRS)

Mcfarland, R. E.

1983-01-01

Nonlinear mathematical models of a rotor system, referred to as rotating blade-element models, produce steady-state, high-frequency harmonics of significant magnitude. In a discrete simulation model, certain of these harmonics may be incompatible with realistic real-time computational constraints because of their aliasing into the operational low-pass region. However, the energy is an aliased harmonic may be suppressed by increasing the computation rate of an isolated, causal nonlinearity and using an appropriate filter. This decontamination technique is applied to Sikorsky's real-time model of the Black Hawk helicopter, as supplied to NASA for handling-qualities investigations.

CRASHWORTHY HELICOPTER GUNNER’S SEAT INVESTIGATION

DTIC Science & Technology

1975-01-01

less restrict- ing to gun motion than a fully armored bucket seat. The problem remains in getting the gunners to wear body armor, and this can be... motions . The adjustable seat back accommodates a gun- ner with or without body armor and troops with or without combat packs and equipment. A back flap...Developmental Retractable Monkey Harness Restraint for UH-l 1 1.9 10 Gunner Survival Vest With Body Armor (ISVESTA) Side View . . . . . . . . *. . ... .. 22

78 FR 23692 - Airworthiness Directives; Eurocopter France Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-22

..., for the Eurocopter AS 350B, BA, BB, B1, B2, B3, and D helicopters, fitted with certain T/R blades... AS350B, BA, B1, B2, B3, and D, and Model AS355E, F, F1, F2, and N helicopters with certain tail rotor (T... that we receive, as well as a report summarizing each substantive public contact with FAA personnel...

Helicopter noise analysis : round-robin test

DOT National Transportation Integrated Search

1981-08-01

This report documents the results of an international round robin test on the analysis of helicopter noise. Digital spectral noise data of a 3.5-second simulated helicopter flyover and identical analog test tapes containing helicopter noise data, ref...

MIZEX, 1984, NASA CV-990 flight report

NASA Technical Reports Server (NTRS)

1985-01-01

During June/July 1984, the NASA CV-990 Airborne Laboratory was utilized in a mission to overly the Fram Strait/East Greenland Sea marginal ice zone (MIZ) during the main summer marginal ice zone experiment (MIZEX '84). The eight data flights were coordinated where possible with overpasses of the Nimbus-7 satellite, and with measurement of sea ice, open ocean, and atmospheric properties at the surface. The surface research teams were based on seven research vessels, some with helicopters: (1) M/V Kvitbjorn, (2) M/V Polarqueen; (3) M/S Haakon Mosby; (4) a M/S H.U. Sverdrup, all from Norway; (5) F/S Polarstern from the Federal Republic of Germany; and (6) the USNS Lynch from the USA. There were also coordinated flights with the NRL P3, NOAA P3, Canadian CV580, and the French B-17 during the overlap portions of their respective missions. Analysis of the real-time data acquired during the mission and uncalibrated data stored on tape has served to indicate the mission was over 90% successful.

77 FR 50582 - Airworthiness Directives; Eurocopter France Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-22

... Airworthiness Directives; Eurocopter France Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for Eurocopter France... 39 to include an AD that would apply to Eurocopter France Model EC155B and EC155B1 helicopters with a...

An investigation of the effects of pitch-roll (de)coupling on helicopter handling qualities

NASA Technical Reports Server (NTRS)

Blanken, C. L.; Pausder, H. J.; Ockier, C. J.

1995-01-01

An extensive investigation of the effects of pitch-roll coupling on helicopter handling qualities was performed by the U.S. Army and Deutsche Forschungsanstalt fur Luft- und Raumfahrt (DLR), using a NASA ground-based and a DLR in-flight simulator. Over 90 different coupling configurations were evaluated using a high gain roll-axis tracking task. The results show that although the current ADS-33C coupling criterion discriminates against those types of coupling typical of conventionally controlled helicopters, it is not always suited for the prediction of handling qualities of helicopters with modern control systems. Based on the observation that high frequency inputs during tracking are used to alleviate coupling, a frequency domain pitch-roll coupling criterion that uses the average coupling ratio between the bandwidth and neutral stability frequency is formulated. This criterion provides a more comprehensive coverage with respect to the different types of coupling, shows excellent consistency, and has the additional benefit that compliance testing data are obtained from the bandwidth/phase delay tests, so that no additional flight testing is needed.

76 FR 53315 - Airworthiness Directives; Eurocopter France Model SA-365N and SA-365N1 Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-26

... of compliance. (d) The Joint Aircraft System/Component Code is 2897: Fuel System Wiring. (e) The... helicopters. This action requires you to disconnect the high level fuel switches in the fuel tanks on the affected helicopters. In addition, for helicopters without a crossfeed between the fuel filler necks, you...

Human Factors Assessment of the UH-60M Common Avionics Architecture System (CAAS) Crew Station During the Limited User Evaluation (LEUE)

DTIC Science & Technology

2005-12-01

weapon system evaluation as a high-level architecture and distributed interactive simulation 6 compliant, human-in-the-loop, virtual environment...Directorate to participate in the Limited Early User Evaluation (LEUE) of the Common Avionics Architecture System (CAAS) cockpit. ARL conducted a human...CAAS, the UH-60M PO conducted a limited early user evaluation (LEUE) to evaluate the integration of the CAAS in the UH-60M crew station. The

The Quest for a Helicopter Suitable for Combat Rescue, 1967-1983.

DTIC Science & Technology

1985-04-01

the war draqged on" (2:7). From this need came the development of the helicopter as a - ascue -,hicle, a development that came late in World War 11. Even...question of future conflicts and the coming jet age forced policy makers to consider the reorganization and expansion of a rescue force capable of...to existing aging H-3s" (6:92). The inadequacies of the USAF’s combat rescue helicopter force, both in terms of mission capabiitic: and number of

NASA Aerospace Flight Battery Program: Wet Life of Nickel-Hydrogen (Ni-H2) Batteries. Volume 1, Part 3

NASA Technical Reports Server (NTRS)

Jung, David S.; Lee, Leonine S.; Manzo, Michelle A.

2010-01-01

This NASA Aerospace Flight Battery Systems Working Group was chartered within the NASA Engineering and Safety Center (NESC). The Battery Working Group was tasked to complete tasks and to propose proactive work to address battery related, agency-wide issues on an annual basis. In its first year of operation, this proactive program addressed various aspects of the validation and verification of aerospace battery systems for NASA missions. Studies were performed, issues were discussed and in many cases, test programs were executed to generate recommendations and guidelines to reduce risk associated with various aspects of implementing battery technology in the aerospace industry. This document contains Part 3 - Volume I: Wet Life of Nickel-Hydrogen (Ni-H2) Batteries of the program's operations.

U.S. EPA, Pesticide Product Label, PCO LINDANE E-1 INSECTICIDE, 09/21/1983

EPA Pesticide Factsheets

2011-04-13

... lid '",1. Uu (e, .~~ • I"I. ~ii.r in ... ,,1".1'~ ... In "'"uh' .... h._H ... l .... CI • .!!. I .. ,.oCll'. '1. II ,11_ •• , 1.1 ..... 1"".1 "1~~lIh" .., hl"'''5 It hrM'. ...

Helicopter technology benefits and needs. Volume 1: Summary

NASA Technical Reports Server (NTRS)

Zuk, J.; Adams, R. J.

1980-01-01

Present public service helicopter benefits and the potential benefits of an advanced public service rotorcraft (200 knots to 300 knots) are summarized. Past and future public service growth is quantified and assessed and needs, problem areas, and desired vehicle characteristics are defined. Research and technology recommendations are formulated and the costs and benefits of research options are assessed.

Multicenter observational prehospital resuscitation on helicopter study.

PubMed

Holcomb, John B; Swartz, Michael D; DeSantis, Stacia M; Greene, Thomas J; Fox, Erin E; Stein, Deborah M; Bulger, Eileen M; Kerby, Jeffrey D; Goodman, Michael; Schreiber, Martin A; Zielinski, Martin D; O'Keeffe, Terence; Inaba, Kenji; Tomasek, Jeffrey S; Podbielski, Jeanette M; Appana, Savitri N; Yi, Misung; Wade, Charles E

2017-07-01

Earlier use of in-hospital plasma, platelets, and red blood cells (RBCs) has improved survival in trauma patients with severe hemorrhage. Retrospective studies have associated improved early survival with prehospital blood product transfusion (PHT). We hypothesized that PHT of plasma and/or RBCs would result in improved survival after injury in patients transported by helicopter. Adult trauma patients transported by helicopter from the scene to nine Level 1 trauma centers were prospectively observed from January to November 2015. Five helicopter systems had plasma and/or RBCs, whereas the other four helicopter systems used only crystalloid resuscitation. All patients meeting predetermined high-risk criteria were analyzed. Patients receiving PHT were compared with patients not receiving PHT. Our primary analysis compared mortality at 3 hours, 24 hours, and 30 days, using logistic regression to adjust for confounders and site heterogeneity to model patients who were matched on propensity scores. Twenty-five thousand one hundred eighteen trauma patients were admitted, 2,341 (9%) were transported by helicopter, of which 1,058 (45%) met the highest-risk criteria. Five hundred eighty-five of 1,058 patients were flown on helicopters carrying blood products. In the systems with blood available, prehospital median systolic blood pressure (125 vs 128) and Glasgow Coma Scale (7 vs 14) was significantly lower, whereas median Injury Severity Score was significantly higher (21 vs 14). Unadjusted mortality was significantly higher in the systems with blood products available, at 3 hours (8.4% vs 3.6%), 24 hours (12.6% vs 8.9%), and 30 days (19.3% vs 13.3%). Twenty-four percent of eligible patients received a PHT. A median of 1 unit of RBCs and plasma were transfused prehospital. Of patients receiving PHT, 24% received only plasma, 7% received only RBCs, and 69% received both. In the propensity score matching analysis (n = 109), PHT was not significantly associated with mortality

Gulf of Mexico Helicopter Offshore System Technologies Engineering Needs Assessment

NASA Technical Reports Server (NTRS)

Koenke, Edmund J.; Carpenter, Elisabeth J.; Williams, Larry; Caiafa, Caesar

1999-01-01

The National Aeronautics and Space Administration (NASA), in partnership with the Federal Aviation Administration (FAA), is conducting a research and development program to modernize the National Airspace System (NAS). The mission of NASA's Advanced Air Transportation Technologies (AATT) project is to develop advanced Air Traffic Management (ATM) concepts and decision support tools for eventual deployment and implementation by the FAA and the private sector. One major objective of the NASA AATT project is to understand and promote the needs of all user classes. The Gulf of Mexico (GoMex) airspace has unique needs. A large number of helicopters operate in this area with only limited surveillance and sometimes-severe environmental conditions. Thunderstorms are the most frequent weather hazard during the spring, summer, and fall. In winter, reduced hours of daylight, low ceilings, strong winds, and icing conditions may restrict operations. Hurricanes impose the most severe weather hazard. The hurricane season, from June through October, normally requires at least one mass evacuation of all offshore platforms.

Preliminary CALET Ultra Heavy Cosmic Ray Abundance Measurements

NASA Astrophysics Data System (ADS)

Rauch, Brian; CALET Collaboration

2017-01-01

The CALorimetric Electron Telescope (CALET) on the International Space Station (ISS) was launched August 19, 2015 and has been returning excellent data for over a year. The main calorimeter (CAL) on CALET measures the fluxes of high-energy electrons, nuclei and gamma rays. In addition to measuring the energy spectra of the more abundant cosmic-ray nuclei through 26Fe, CAL has the dynamic range to measure the abundances of the ultra-heavy (UH) cosmic-ray nuclei through 40Zr. In an anticipated 5 year mission on the ISS CALET will collect a UH data set with statistics comparable to that achieved with the first flight of the SuperTIGER balloon-borne instrument. The CALET space-based measurement has the advantage of not requiring corrections for atmospheric losses, and unlike other UH measurements the abundances of all nuclei from 1H through 40Zr are observed with the same instrument. We present preliminary CALET UH analysis results from the first year of operation. This research was supported by NASA at Washington University under Grant Number NNX11AE02G.

78 FR 33770 - Airworthiness Directives; Bell Helicopter Textron, Inc. Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-05

... Textron, Inc. (Bell) Model 206A, 206B, 206L, 206L-1, 206L-3, 206L-4, and 407 helicopters with an Apical Industries, Inc. (Apical) emergency float kit installed under supplemental type certificate (STC) number... after receipt. For service information identified in this proposed AD, contact Apical Industries, Inc...

Impact of flying qualities on mission effectiveness for helicopter air combat, volume 1

NASA Technical Reports Server (NTRS)

Harris, T. M.; Beerman, D. A.

1983-01-01

A computer simulation to investigate the impact of flying qualities on mission effectiveness is described. The objective of the study was to relate the effects of flying qualities, such as precision of flight path control and pilot workload, to the ability of a single Scout helicopter, or helicopter team, to accomplish a specified anti-armor mission successfully. The model of the actual engagement is a Monte Carlo simulation that has the capability to assess the effects of helicopter characteristics, numbers, tactics and weaponization on the force's ability to accomplish a specific mission against a specified threat as a function of realistic tactical factors. A key feature of this program is a simulation of micro-terrain features and their effects on detection, exposure, and masking for nap-of-the-earth (NOE) flight.

Alloy NASA-HR-1

NASA Technical Reports Server (NTRS)

Chen, Po-Shou; Mitchell, Michael

2005-01-01

NASA-HR-1 is a high-strength Fe-Ni-base superalloy that resists high-pressure hydrogen environment embrittlement (HEE), oxidation, and corrosion. Originally derived from JBK-75, NASA-HR-1 has exceptional HEE resistance that can be attributed to its gamma-matrix and eta-free (Ni3Ti) grain boundaries. The chemistry was formulated using a design approach capable of accounting for the simultaneous effects of several alloy additions. This approach included: (1) Systematically modifying gamma-matrix compositions based on JBK-75; (2) Increasing gamma (Ni3(Al,Ti)) volume fraction and adding gamma-matrix strengthening elements to obtain higher strength; and (3) Obtaining precipitate-free grain boundaries. The most outstanding attribute of NASA-HR-1 is its ability to resist HEE while showing much improved strength. NASA-HR-1 has approximately 25% higher yield strength than JXK-75 and exhibits tensile elongation of more than 20% with no ductility loss in a hydrogen environment at 5 ksi, an achievement unparalleled by any other commercially available alloy. Its Cr and Ni contents provide exceptional resistance to environments that promote oxidation and corrosion. Microstructural stability was maintained by improved solid solubility of the gamma-matrix, along with the addition of alloying elements to retard eta (Ni3Ti) precipitation. NASA-HR-1 represents a new system that greatly extends the compositional ranges of existing HEE-resistant Fe-Ni-base superalloys.

Price-Weight Relationships of General Aviation, Helicopters, Transport Aircraft and Engines

NASA Technical Reports Server (NTRS)

Anderson, Joseph L.

1981-01-01

The NASA must assess its aeronautical research program with economic as well as performance measures. It thus is interested in what price a new technology aircraft would carry to make it attractive to the buyer. But what price a given airplane or helicopter will carry is largely a reflection of the manufacturer's assessment of the competitive market into which the new aircraft will be introduced. The manufacturer must weigh any new aerodynamic or system technology innovation he would add to an aircraft by the impact of this innovation upon the aircraft's cost to manufacture, economic attractiveness and price. The intent of this paper is to give price standards against which new technologies and the NASA's research program can be assessed. Using reported prices for sailplanes, general aviation, agriculture, helicopter, business and transport aircraft, price estimating relations in terms of engine and airframe characteristics have been developed. The relations are given in terms of the aircraft type, its manufactured empty weight, engine weight, horsepower or thrust. Factors for the effects of inflation are included to aid in making predictions of future aircraft prices. There are discussions of aircraft price in terms of number of passenger seats, airplane size and research and development costs related to an aircraft model, and indirectly how new technologies, aircraft complexity and inflation have affected these.

Ground-Based Observations of 9P/Tempel 1 - The Deep Impact Mission

NASA Astrophysics Data System (ADS)

Meech, K. J.; Bauer, J. M.; A'Hearn, M. F.

1999-09-01

The Deep Impact mission, one of the two recently approved Discovery missions, will deliver a 500 kg copper projectile to the comet 9P/Tempel 1 on July 4, 2005, to excavate a crater. The goal will be to watch the cratering event, measure the change in activity level caused by the impact, and will be the first experiment to sample deeply below the surface of a comet. In preparation for a successful mission, we will begin a vigorous ground-based observing campaign to characterize the nucleus of 9P/Tempel 1. The ground-based observations will characterize the pre-impact activity levels for comparison after the impact, characterize the nucleus in terms of a rotational light curve and pole position, get an estimate of the nucleus size and albedo, model the dust production rates, and search for the appearance of gaseous species as the comet approaches perihelion. The observing campaign as already begun with some intensive observations of the comet during the following observing runs: UT Date & Nts & Telescope & r[AU] & No. & Exp 12/97 & 1 &Keck II & 4.48 & 2 & 240 1/98 & 1 &UH 2.2m & 4.44 & 7 & 4200 2/98 & 1 &CTIO1.5m & 4.36 & 3 & 1800 4/98 & 2 &UH 2.2m & 4.26 & 8 & 4800 1/99 & 6 &UH 2.2m & 3.14 &133 &17220 3/99 & 4 &UH 2.2m & 2.88 &181 &54000 5/99 & 2 &UH 2.2m & 2.47 & 9 & 810 7 /99 & 2 &UH 2.2m & 2.19 & 9 & 1620 The 1999 January and March observations were made to search for the rotation period of the comet, as well as to obtain deep images to model the coma. The results of the rotational light curve observations will be presented, as well as a compilation of the heliocentric light curve from the data from earlier epochs. In addition, a detailed, comprehensive multi-wavelength ground-based observing plan will be presented to characterize the nucleus before the 2005 July 4 Deep Impact encounter with the comet. This project has been funded through the NASA Planetary Astronomy Program to date, NAG 4494.

NASA historical data book. Volume 1: NASA resources 1958-1968

NASA Technical Reports Server (NTRS)

Vannimmen, Jane; Bruno, Leonard C.; Rosholt, Robert L.

1988-01-01

This is Volume 1, NASA Resources 1958-1968, of a multi-volume series providing a 20-year compilation of summary statistical and other data descriptive of NASA's programs in aeronautics and manned and unmanned spaceflight. This series is an important component of NASA published historical reference works, used by NASA personnel, managers, external researchers, and other government agencies.

Helicopter discrimination apparatus for the murine radar

DOEpatents

Webb, Jr., John G.; Gray, Roger M.

1977-01-01

A helicopter discrimination apparatus for a radar utilizing doppler filtering to discriminate between a missile and ground clutter. The short duration of the doppler filter pulses which are emitted by helicopter rotor blades are processed to prevent false alarms, thus allowing the radar-protected helicopter to operate in formation with other helicopters while maintaining protection against infra-red-seeking missiles.

Loads and Performance Data from a Wind-Tunnel Test of Generic Model Helicopter Rotor Blades

NASA Technical Reports Server (NTRS)

Yeager, William T., Jr.; Wilbur, Matthew L.

2005-01-01

An investigation was conducted in the NASA Langley Transonic Dynamics Tunnel to acquire data for use in assessing the ability of current and future comprehensive analyses to predict helicopter rotating-system and fixed-system vibratory loads. The investigation was conducted with a generic model helicopter rotor system using blades with rectangular planform, no built-in twist, uniform radial distribution of mass and stiffnesses, and a NACA 0012 airfoil section. Rotor performance data, as well as mean and vibratory components of blade bending and torsion moments, fixed-system forces and moments, and pitch link loads were obtained at advance ratios up to 0.35 for various combinations of rotor shaft angle-of-attack and collective pitch. The data are presented without analysis.

Multimission helicopter cockpit displays

NASA Astrophysics Data System (ADS)

Terry, William S.; Terry, Jody K.; Lovelace, Nancy D.

1996-05-01

A new operator display subsystem is being incorporated as part of the next generation United States Navy (USN) helicopter avionics system to be integrated into the multi-mission helicopter (MMH) that replaces both the SH-60B and the SH-60F in 2001. This subsystem exploits state-of-the-art technology for the display hardware, the display driver hardware, information presentation methodologies, and software architecture. Both of the existing SH-60 helicopter display systems are based on monochrome CRT technology; a key feature of the MMH cockpit is the integration of color AMLCD multifunction displays. The MMH program is one of the first military programs to use modified commercial AMLCD elements in a tactical aircraft. This paper presents the general configuration of the MMH cockpit and multifunction display subsystem and discusses the approach taken for presenting helicopter flight information to the pilots as well as presentation of mission sensor data for use by the copilot.

Civil helicopter noise assessment study Boeing-Vertol model 347. [recommendations for reduction of helicopter noise levels

NASA Technical Reports Server (NTRS)

Hinterkeuser, E. G.; Sternfeld, H., Jr.

1974-01-01

A study was conducted to forecast the noise restrictions which may be imposed on civil transport helicopters in the 1975-1985 time period. Certification and community acceptance criteria were predicted. A 50 passenger tandem rotor helicopter based on the Boeing-Vertol Model 347 was studied to determine the noise reductions required, and the means of achieving them. Some of the important study recommendations are: (1) certification limits should be equivalent to 95 EPNdb at data points located at 500 feet to each side of the touchdown/takeoff point, and 1000 feet from this point directly under the approach and departure flight path. (2) community acceptance should be measured as Equivalent Noise Level (Leq), based on dBA, with separate limits for day and night operations, and (3) in order to comply with the above guidelines, the Model 347 helicopter will require studies and tests leading to several modifications.

78 FR 34279 - Airworthiness Directives; Bell Helicopter Textron Canada Limited (Bell) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-07

.... Discussion Transport Canada (TC), which is the aviation authority for Canada, has issued TC AD No. CF-2005-24, dated July 4, 2005, to correct an unsafe condition for Model 230 helicopters. TC advises of several... these failures have occurred on the same engine used by Bell on Model 230 helicopters. According to TC...

Investigating Flight with a Toy Helicopter

ERIC Educational Resources Information Center

Liebl, Michael

2010-01-01

Flight fascinates people of all ages. Recent advances in battery technology have extended the capabilities of model airplanes and toy helicopters. For those who have never outgrown a childhood enthusiasm for the wonders of flight, it is possible to buy inexpensive, remotely controlled planes and helicopters. A toy helicopter offers an opportunity…

77 FR 30230 - Airworthiness Directives; Eurocopter Deutschland Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

... September 30, 2011. (g) Subject Joint Aircraft Service Component (JASC) Code: 2436: DC Generator Control... Deutschland GmbH Model MBB-BK117 C-2 helicopters with certain Generator Control Units (GCU) installed. This..., West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001. Hand...

Acoustic treatment of the NASA Langley 4- by 7-meter tunnel: A feasibility study

NASA Technical Reports Server (NTRS)

Yu, J. C.; Abrahamson, A. L.

1986-01-01

A feasibility study for upgrading the NASA Langley 4- by 7-Meter Tunnel so that it may be used for aeroacoustic research related to helicopters is described. The requirements for noise research leading to the design of the next generation of helicopters impose a set of acoustic test criteria that no existing wind tunnel in the United States can presently meet. Included in this feasibility study are the following considerations: (1) an evaluation of general wind-tunnel requirements and desired tunnel background noise levels for helicopter aeroacoustic research; (2) an assessment of the present acoustic environment for testing model rotors; (3) a diagnostic investigation of tunnel background noise sources and paths; (4) acoustic treatment options for tunnel background noise reduction and a trade-off study between these options; (5) an engineering feasibility assessment of the selected option; and (6) an integrated analysis of study components and recommendations of treatment for an approach to meet the tunnel background noise reduction goal. It is concluded that the Langley 4- by 7-Meter Tunnel is a fundamentally suitable facility for helicopter aeroacoustic research. It is also concluded that acoustic treatment of this facility for meeting the required tunnel background noise goal can be accomplished technically at reasonable risk and cost.

Correlation of finite-element structural dynamic analysis with measured free vibration characteristics for a full-scale helicopter fuselage

NASA Technical Reports Server (NTRS)

Kenigsberg, I. J.; Dean, M. W.; Malatino, R.

1974-01-01

The correlation achieved with each program provides the material for a discussion of modeling techniques developed for general application to finite-element dynamic analyses of helicopter airframes. Included are the selection of static and dynamic degrees of freedom, cockpit structural modeling, and the extent of flexible-frame modeling in the transmission support region and in the vicinity of large cut-outs. The sensitivity of predicted results to these modeling assumptions are discussed. Both the Sikorsky Finite-Element Airframe Vibration analysis Program (FRAN/Vibration Analysis) and the NASA Structural Analysis Program (NASTRAN) have been correlated with data taken in full-scale vibration tests of a modified CH-53A helicopter.

78 FR 34290 - Airworthiness Directives; Bell Helicopter Textron Canada Limited (Bell) Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-07

.... Discussion Transport Canada (TC), which is the aviation authority for Canada, has issued TC AD No. CF-2005-25, dated July 5, 2005, to correct an unsafe condition for Model 430 helicopters. TC advises of several... turbine wheel is installed on the 250-C40B engine used by Bell on Model 430 helicopters. According to TC...

Validation of vision-based obstacle detection algorithms for low-altitude helicopter flight

NASA Technical Reports Server (NTRS)

Suorsa, Raymond; Sridhar, Banavar

1991-01-01

A validation facility being used at the NASA Ames Research Center is described which is aimed at testing vision based obstacle detection and range estimation algorithms suitable for low level helicopter flight. The facility is capable of processing hundreds of frames of calibrated multicamera 6 degree-of-freedom motion image sequencies, generating calibrated multicamera laboratory images using convenient window-based software, and viewing range estimation results from different algorithms along with truth data using powerful window-based visualization software.

International Aerospace and Ground Conference on Lightning and Static Electricity. 1984 technical papers. Supplement