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 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 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 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 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 FLIGHT TIME IDENTIFICATION OF UH 60A HELICOPTER AND SLUNG LOAD NASA TM 1998 112231 OCT 27 1998 written by United States. National Aeronautics and Space Administration and published by . This book was released on 1999* with total page 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 NASTRAN Modeling of Flight Test Components for UH 60A Airloads Program Test Configuration written by Florentino Idosor and published by . This book was released on 1993 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1999 with total page 1144 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 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 Validation Flight Test of UH 60A for Rotorcraft Systems Integration Simulator RSIS written by and published by . This book was released on 1982 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: The United States Army Aviation Engineering Flight Activity (USAAEFA) conducted flight tests of the UH-60A helicopter for the Aeromechanics Laboratory (AL)of the US Army Aviation Research and Technology Laboratories to obtain data for validation of a simulator. A test program of sixty-nine flights totaling 97.4 tests hours was flown to provide AL with extensive handling qualities data. In addition to standard handling qualities tests, special system identification maneuvers were flown. Summary results of those tests are contained in this report.
Download or read book Fidelity Assessment of a Uh 60a Simulation on the NASA Ames Vertical Motion Simulator written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-24 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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. Atencio, Adolph, Jr. Ames Research Center NASA-TM-104016, A-93071, NAS 1.15:104016, USAATC-TR-93-A-005, AD-A271172 RTOP 505-59-52...
Download or read book Validation of a Real time Engineering Simulation of the UH 60A Helicopter written by Mark G. Ballin and published by . This book was released on 1987 with total page 208 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 Maintenance Test Flight Manual written by and published by . This book was released on 1990 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
