Download or read book Flight Test Identification and Simulation of a UH 60A Helicopter and Slung Load written by and published by . This book was released on 2001 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Flight Time Identification of a UH 60A Helicopter and Slung Load written by and published by . This book was released on 1998 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of the American Helicopter Society written by American Helicopter Society and published by . This book was released on 2001 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flight Testing and Real Time System Identification Analysis of a UH 60A Black Hawk Helicopter with an Instrumented External Sling Load written by Allen H. McCoy and published by . This book was released on 1997-12 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 US 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 US Army Black Hawk helicopter with various external loads. Tests were conducted as the US 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 it's control system's stability margins. Included were calculations of the stability characteristics of the load's pendular motion. Utilizing CIFER software, a method for near-real time system identification was also demonstrated during the flight test program.
Download or read book Flight Time Identification of a Uh 60a Helicopter and Slung Load written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-03 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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. Cicolani, Luigi S. and McCoy, Allen H. and Tischler, Mark B. and Tucker, George E. and Gatenio, Pinhas and Marmar, Dani Ames Research Center RTOP 581-30-22...
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1999-07 with total page 1154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Aeronautical Journal written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flight Testing and Real Time System Identification Analysis of a Uh 60a Black Hawk Helicopter with an Instrumented External Sling Load written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-06 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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-...
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1042 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Identification Des Syst mes Pour Le D veloppement Int gr Des A ronefs Et Les Essais en Vol written by and published by . This book was released on 1999 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Verti flite written by and published by . This book was released on 2002 with total page 868 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 1572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation Validation and Flight Prediction of UH 60A Black Hawk Helicopter Slung Load Characteristics written by Peter H. Tyson and published by . This book was released on 1999-03-01 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: Helicopter/slung load systems are two body systems in which the slung load adds its rigid body dynamics, aerodynamics, and sling stretching dynamics to the helicopter. The slung load can degrade helicopter handling qualities and reduce the flight envelope of the helicopter. Confirmation of system stability parameters and envelope is desired, but flight test evaluation is time consuming and costly. A simulation model validated for handling quality assessments would significantly reduce resources expended in flight testing while increasing efficiency, productivity, and safety by aiding researchers, designers, and pilots to understand factors affecting helicopter-slung load handling qualities. This thesis describes a comprehensive dynamics and aerodynamics model for slung load simulation, obtained by integrating the NASA Ames Gen Hel UH-60A simulation with slung load equations of motion. Frequency domain analysis is used to compare simulation to flight test frequency responses and key system stability parameters. Results are given for no load, a 4K lb Block, and a 4K lb CONEX load. Handling quality parameters, stability margins, and load pendulum motion roots for cases without load aerodynamics and with static wind tunnel data were compared. Results illustrated state-of-the-art simulation modeling of helicopter/slung load dynamics and its accuracy in predicting key dynamic parameters of interest.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1996 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flight Research at Ames written by Paul F. Borchers and published by . This book was released on 1999 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Department of Housing and Urban Development independent Agencies Appropriations for 1985 written by United States. Congress. House. Committee on Appropriations. Subcommittee on HUD-Independent Agencies and published by . This book was released on 1984 with total page 1722 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Department of Housing and Urban Development independent Agencies Appropriations for 1985 National Aeronautics and Space Administration written by United States. Congress. House. Committee on Appropriations. Subcommittee on HUD-Independent Agencies and published by . This book was released on 1984 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt:
