Download or read book An Overview of the NASA F 18 High Alpha Research Vehicle written by Albion H. Bowers and published by . This book was released on 1996 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Overview of Controls and Flying Qualities Technology on the F a 18 High Alpha Research Vehicle written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-30 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NASA F/A-18 High Alpha Research Vehicle (HARV) has been the flight test bed of a focused technology effort to significantly increase maneuvering capability at high angles of attack. Development and flight test of control law design methodologies, handling qualities metrics, performance guidelines, and flight evaluation maneuvers are described. The HARV has been modified to include two research control effectors, thrust vectoring, and actuated forebody strakes in order to provide increased control power at high angles of attack. A research flight control system has been used to provide a flexible, easily modified capability for high-angle-of-attack research controls. Different control law design techniques have been implemented and flight-tested, including eigenstructure assignment, variable gain output feedback, pseudo controls, and model-following. Extensive piloted simulation has been used to develop nonlinear performance guide-lines and handling qualities criteria for high angles of attack. This paper reviews the development and evaluation of technologies useful for high-angle-of-attack control. Design, development, and flight test of the research flight control system, control laws, flying qualities specifications, and flight test maneuvers are described. Flight test results are used to illustrate some of the lessons learned during flight test and handling qualities evaluations. Pahle, Joseph W. and Wichman, Keith D. and Foster, John V. and Bundick, W. Thomas Armstrong Flight Research Center; Langley Research Center ...

Download or read book High Alpha Handling Qualities Flight Research on the NASA F A 18 High Alpha Research Vehicle written by Keith D. Wichman and published by . This book was released on 1996 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Alpha Research Vehicle Lateral Directional Control Law Description Analyses and Simulation Results written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-08 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report contains a description of a lateral-directional control law designed for the NASA High-Alpha Research Vehicle (HARV). The HARV is a F/A-18 aircraft modified to include a research flight computer, spin chute, and thrust-vectoring in the pitch and yaw axes. Two separate design tools, CRAFT and Pseudo Controls, were integrated to synthesize the lateral-directional control law. This report contains a description of the lateral-directional control law, analyses, and nonlinear simulation (batch and piloted) results. Linear analysis results include closed-loop eigenvalues, stability margins, robustness to changes in various plant parameters, and servo-elastic frequency responses. Step time responses from nonlinear batch simulation are presented and compared to design guidelines. Piloted simulation task scenarios, task guidelines, and pilot subjective ratings for the various maneuvers are discussed. Linear analysis shows that the control law meets the stability margin guidelines and is robust to stability and control parameter changes. Nonlinear batch simulation analysis shows the control law exhibits good performance and meets most of the design guidelines over the entire range of angle-of-attack. This control law (designated NASA-1A) was flight tested during the Summer of 1994 at NASA Dryden Flight Research Center. Davidson, John B. and Murphy, Patrick C. and Lallman, Frederick J. and Hoffler, Keith D. and Bacon, Barton J. Langley Research Center...

Download or read book In flight Flow Visualization Characteristics of the NASA F 18 High Alpha Research Vehicle at High Angles of Attack written by David F. Fisher and published by . This book was released on 1991 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summary of In flight Flow Visualization Obtained from the NASA High Alpha Research Vehicle written by David F. Fisher and published by . This book was released on 1991 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In flight Flow Field Analysis on the NASA F 18 High Alpha Research Vehicle with Comparisons to Ground Facility Data written by John H. Del Frate and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thrust Vectoring on the NASA F 18 High Alpha Research Vehicle written by Albion H. Bowers and published by . This book was released on 1996 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In Flight Flow Visualization Characteristics of the NASA F 18 High Alpha Research Vehicle at High Angles of Attack written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-05 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface and off-surface flow visualization techniques were used to visualize the 3-D separated flows on the NASA F-18 high alpha research vehicle at high angles of attack. Results near the alpha = 25 to 26 deg and alpha = 45 to 49 deg are presented. Both the forebody and leading edge extension (LEX) vortex cores and breakdown locations were visualized using smoke. Forebody and LEX vortex separation lines on the surface were defined using an emitted fluid technique. A laminar separation bubble was also detected on the nose cone using the emitted fluid technique and was similar to that observed in the wind tunnel test, but not as extensive. Regions of attached, separated, and vortical flow were noted on the wing and the leading edge flap using tufts and flow cones, and compared well with limited wind tunnel results. Fisher, David F. and Delfrate, John H. and Richwine, David M. Ames Research Center; Armstrong Flight Research Center RTOP 505-68-71...

Download or read book High Alpha Research Vehicle Lateral Directional Control Law Description Analyses and Simulation Results written by John B. Davidson and published by . This book was released on 1998 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In Flight Wing Pressure Distributions for the NASA F A 18a High Alpha Research Vehicle written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pressure distributions on the wings of the F/A-18A High Alpha Research Vehicle (HARV) were obtained using both flush-mounted pressure orifices and surface-mounted pressure tubing. During quasi-stabilized 1-g flight, data were gathered at ranges for angle of attack from 5 deg to 70 deg, for angle of sideslip from -12 deg to +12 deg, and for Mach from 0.23 to 0.64, at various engine settings, and with and without the leading edge extension fence installed. Angle of attack strongly influenced the wing pressure distribution, as demonstrated by a distinct flow separation pattern that occurred between the range from 15 deg to 30 deg. Influence by the leading edge extension fence was evident on the inboard wing pressure distribution, but little influence was seen on the outboard portion of the wing. Angle-of-sideslip influence on wing pressure distribution was strongest at low angle of attack. Influence of Mach number was observed in the regions of local supersonic flow, diminishing as angle of attack was increased. Engine throttle setting had little influence on the wing pressure distribution.Davis, Mark C. and Saltzman, John A.Armstrong Flight Research CenterWINGS; PRESSURE DISTRIBUTION; WIND TUNNEL TESTS; F-18 AIRCRAFT; RESEARCH VEHICLES; LIFT; ORIFICES; SUPERSONIC FLOW; BOUNDARY LAYER SEPARATION; DATA REDUCTION; COMPUTATIONAL FLUID DYNAMICS; PIPES (TUBES); FLOW VISUALIZATION; FLIGHT TESTS; ANGLE OF ATTACK

Download or read book Flying beyond the stall written by Douglas A. Joyce and published by . This book was released on 2014 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: The X-31 Enhanced Fighter Maneuverability Demonstrator was unique among experimental aircraft. A joint effort of the United States and Germany, the X-31 was the only X-plane to be designed, manufactured, and flight tested as an international collaboration. It was also the only X-plane to support two separate test programs conducted years apart, one administered largely by NASA and the other by the U.S. Navy, as well as the first X-plane ever to perform at the Paris Air Show. Flying Beyond the Stall begins by describing the government agencies and private-sector industries involved in the X-31 program, the genesis of the supermaneuverability concept and its initial design breakthroughs, design and fabrication of two test airframes, preparation for the X-31's first flight, and the first flights of Ship #1 and Ship #2. Subsequent chapters discuss envelope expansion, handling qualities (especially at high angles of attack), and flight with vectored thrust. The book then turns to the program's move to NASA's Dryden Flight Research Center and actual flight test data. Additional tasking, such as helmet-mounted display evaluations, handling quality studies, aerodynamic parameter estimation, and a "tailless" study are also discussed.The book describes how, in the aftermath of a disastrous accident with Ship #1 in 1995, Ship #2 was prepared for its outstanding participation in the Paris Air Show. The aircraft was then shipped back to Edwards AFB and put into storage until the late 1990s, when it was refurbished for participation in the U. S. Navy's VECTOR program. The book ends with a comprehensive discussion of lessons learned and includes an Appendix containing detailed information.

Download or read book Overview of the NASA Dryden Flight Research Facility Aeronautical Flight Projects written by and published by . This book was released on 1992 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flight Determined Subsonic Lateral Directional Stability and Control Derivatives of the Thrust Vectoring F 18 High Angle of Attack Research Vehicle HARV and Comparisons to the Basic F 18 and Predicted Derivatives written by Kenneth W. Iliff and published by . This book was released on 1999 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Forebody Flow Visualization on the F 18 HARV with Actuated Forebody Strakes written by David F. Fisher and published by . This book was released on 1998 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Off-surface smoke flow visualization and extensive pressure measurements were obtained on the forebody of the NASA F-18 High Alpha Research Vehicle equipped with actuated forebody strakes. Test points at [alpha]=50 deg. were examined in which only one strake was deflected or in which both strakes were deflected differentially. The forebody pressures were integrated to obtain forebody yawing moments. Results showed that small single strake deflections can cause an undesirable yawing moment reversal. At [alpha]=50 deg., this reversal was corrected by deploying both strakes at 20 deg. initially, then differentially from 20 deg. to create a yawing moment. The off-surface flow visualization showed that in the case of the small single strake deflection, the resulting forebody/strake vortex remained close to the surface and caused accelerated flow and increased suction pressures on the deflected side. When both strakes were deflected differentially, two forebody/strake vortices were present. The forebody/strake vortex from the larger deflection would lift from the surface while the other would remain close to the surface. The nearer forebody/strake vortex would cause greater flow acceleration, higher suction pressures and a yawing moment on that side ot the forebody. Flow visualization provided clear description of the strake vortices fluid mechanics.

Download or read book In flight Wing Pressure Distributions for the NASA F A 18A High Alpha Research Vehicle written by Mark C. Davis and published by . This book was released on 2000 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pressure distributions on the wings of the F/A-18A High Alpha Research Vehicle (HARV) were obtained using both flush-mounted pressure orifices and surface-mounted pressure tubing. During quasi-stabilized 1-g flight, data were gathered at ranges for angle of attack from 5 to 70 degrees, for angle of sideslip from -12 to +12 degrees, and for Mach from 0.23 to 0.64, at various engine settings, and with and without the leading edge extension fence installed. Angle of attack strongly influenced the wing pressure distribution, as demonstrated by a distinct flow separation pattern that occurred between the range from 15 to 30 degrees. Influence was seen on the outboard portion of the wing. Angle-of-sideslip influence on wing pressure distribution was strongest at low angle of attack. Influence of Mach number was observed in the regions of local supersonic flow, diminshing as angle of attack was increased. Engine throttle setting had little influence on the wing pressure distribution.

Download or read book The Power for Flight written by Jeremy R. Kinney and published by Government Printing Office. This book was released on 2018-02-15 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NACA and aircraft propulsion, 1915-1958 -- NASA gets to work, 1958-1975 -- The shift toward commercial aviation, 1966-1975 -- The quest for propulsive efficiency, 1976-1989 -- Propulsion control enters the computer era, 1976-1998 -- Transiting to a new century, 1990-2008 -- Toward the future