Flight-Determined Subsonic Longitudinal Stability and Control Derivatives of the F-18 High Angle of Attack Research Vehicle (HARV) With Thrust Vectoring

The subsonic longitudinal stability and control derivatives of the F-18 High Angle of Attack Research Vehicle (HARV) are extracted from dynamic flight data using a maximum likelihood parameter identification technique. The technique uses the linearized aircraft equations of motion in their continuous/discrete form and accounts for state and measurement noise as well as thrust-vectoring effects. State noise is used to model the uncommanded forcing function caused by unsteady aerodynamics over the aircraft, particularly at high angles of attack. Thrust vectoring was implemented using electrohydraulically-actuated nozzle postexit vanes and a specialized research flight control system. During maneuvers, a control system feature provided independent aerodynamic control surface inputs and independent thrust-vectoring vane inputs, thereby eliminating correlations between the aircraft states and controls. Substantial variations in control excitation and dynamic response were exhibited for maneuvers conducted at different angles of attack. Opposing vane interactions caused most thrust-vectoring inputs to experience some exhaust plume interference and thus reduced effectiveness. The estimated stability and control derivatives are plotted, and a discussion relates them to predicted values and maneuver quality.

[1]  Andrew J. Yuhas,et al.  Design and development of an F/A-18 inlet distortion rake: A cost and time saving solution , 1994 .

[2]  Gautam H. Shah Wind tunnel investigation of aerodynamic and tail buffet characteristics of leading-edge extension modifications to the F/A-18 , 1991 .

[3]  David M. Richwine,et al.  In-Flight Flow Visualization Characteristics of the NASA F-18 High Alpha Research Vehicle at High Angles of Attack , 1989 .

[4]  R. E. Curry,et al.  A smoke generator system for aerodynamic flight research , 1989 .

[5]  Steven A. Johnson Aircraft ground test and subscale model results of axial thrust loss caused by thrust vectoring using turning vanes , 1992 .

[6]  Chris L. Pettit,et al.  Full-scale wind-tunnel pressure measurements of an F/A-18 tail during buffet , 1996 .

[7]  Michael R. Earls,et al.  Experience with Ada on the F-18 High Alpha Research Vehicle flight test program , 1992 .

[8]  V. Chacon,et al.  Validation of the F-18 high alpha research vehicle flight control and avionics systems modifications , 1990, 9th IEEE/AIAA/NASA Conference on Digital Avionics Systems.

[9]  T. Teichmann,et al.  Dynamics of Flight: Stability and Control , 1959 .

[10]  C Asbury Scott,et al.  A Static Investigation of the Thrust Vectoring System of the F/A-18 High-Alpha Research Vehicle , 1992 .

[11]  Joseph W. Pahle,et al.  Thrust Vectoring on the NASA F-18 High Alpha Research Vehicle , 1996 .

[12]  J. R. Chambers High-angle-of-attack aerodynamics - Lessons learned , 1986 .

[13]  Gary E. Erickson Wind tunnel investigation of vortex flows on F/A-18 configuration at subsonic through transonic speed , 1991 .

[14]  Scott M. Murman,et al.  Numerical simulation of the flow about an F-18 aircraft in the high-alpha regime , 1994 .

[15]  C Asbury Scott,et al.  Multiaxis Thrust-Vectoring Characteristics of a Model Representative of the F-18 High-Alpha Research Vehicle at Angles of Attack From 0 to 70 , 1995 .

[16]  R. E. Maine,et al.  Application of parameter estimation to aircraft stability and control: The output-error approach , 1986 .

[17]  David F. Fisher,et al.  In-flight flow visualization and pressure measurements at low speeds on the NASA F-18 high alpha research vehicle , 1990 .

[18]  Farhad Ghaffari,et al.  Navier-Stokes, flight, and wind tunnel flow analysis for the F/A-18 aircraft , 1994 .

[19]  David F. Fisher,et al.  Summary of in-flight flow visualization obtained from the NASA high alpha research vehicle , 1991 .

[20]  R. E. Maine,et al.  Practical aspects of a maximum likelihood estimation method to extract stability and control derivatives from flight data , 1976 .

[21]  K. W. Iliff,et al.  Extraction of Lateral-Directional Stability and Control Derivatives for the Basic F-18 Aircraft at High Angles of Attack , 1997 .

[22]  Scott M. Murman,et al.  Computation of F/A-18 tail buffet , 1996 .

[23]  R. E. Maine,et al.  SUBSONIC STABILITY AND CONTROL DERIVATIVES FOR AN UNPOWERED, REMOTELY PILOTED 3/8-SCALE F-15 AIRPLANE MODEL OBTAINED FROM FLIGHT TEST , 1976 .

[24]  David M. Richwine,et al.  In-flight leading-edge extension vortex flow-field survey measurements on a F-18 aircraft at high angle of attack , 1991 .

[25]  Russell M. Cummings,et al.  Navier-Stokes predictions of the flowfield around the F-18 (HARV) wing and fuselage at large incidence , 1990 .

[26]  Joseph W. Pahle,et al.  Controls for Agility Research in the NASA High-Alpha Technology Program , 1991 .

[27]  Daniel W. Banks,et al.  Surface flow visualization of separated flows on the forebody of an F-18 aircraft and wind-tunnel model , 1988 .

[28]  M. L. Mason,et al.  Multiaxis thrust vectoring using axisymmetric nozzles and postexit vanes on an F/A-18 configuration vehicle , 1991 .

[29]  Daniel W. Banks,et al.  F-18 high alpha research vehicle surface pressures: Initial in-flight results and correlation with flow visualization and wind-tunnel data , 1990 .

[30]  Aaron J. Ostroff,et al.  High-Alpha Research Vehicle (HARV) longitudinal controller: Design, analyses, and simulation resultss , 1994 .

[31]  Joseph W. Pahle,et al.  Design of a mixer for the thrust-vectoring system on the high-alpha research vehicle , 1996 .

[32]  Kenneth W. Iliff,et al.  Identification and Stochastic Control of an Aircraft Flying in Turbulence , 1978 .

[33]  Stephen A. Whitmore,et al.  Development of a Pneumatic High-Angle-of-Attack Flush Airdata Sensing (HI-FADS) System , 2022 .

[34]  Scott M. Murman,et al.  Coupled numerical simulation of the external and engine inlet flows for the F-18 at large incidence , 1992 .

[35]  F. C. Tang,et al.  Characteristics of the surface pressures on a F/A-18 vertical fin due to buffet , 1994 .

[36]  Vladislav Klein,et al.  Aerodynamic parameters of High-Angle-of attack Research Vehicle (HARV) estimated from flight data , 1990 .

[37]  Susan Z. Zeleznik,et al.  Comparison of the F/A-18A inlet flow analysis with flight data. Part 2 , 1996 .

[38]  Luat T. Nguyen,et al.  Control research in the NASA high-alpha technology program , 1990 .

[39]  Joseph W. Pahle,et al.  An Overview of the NASA F-18 High Alpha Research Vehicle , 1996 .

[40]  Stephen A. Whitmore,et al.  Development of a pneumatic high-angle-of-attack flush airdata sensing system , 1991 .

[41]  Gautam H. Shah,et al.  AIAA 93-3675 CP Actuated Forebody Strake Controls for the F-18 High-Alpha Research Vehicle , 1995 .

[42]  Victoria Regenie,et al.  The F-18 High Alpha Research Vehicle: A High-Angle-of-Attack Testbed Aircraft , 1992 .

[43]  Larry A. Meyn,et al.  Full-scale wind-tunnel studies of F/A-18 tail buffet , 1996 .

[44]  Ronald J. Ray Evaluation of various thrust calculation techniques on an F404 engine , 1990 .

[45]  Stephen A. Whitmore,et al.  Preliminary results from a subsonic high angle-of-attack flush airdata sensing (HI-FADS) system: Design, calibration, and flight test evaluation , 1990 .

[46]  K. W. Iliff,et al.  Determination of stability derivatives from flight data using a Newton-Raphson minimization technique , 1972 .

[47]  Stephen A. Whitmore,et al.  Flight and wind-tunnel calibrations of a flush airdata sensor at high angles of attack and sideslip and at supersonic Mach numbers , 1993 .

[48]  Yehia M. Rizk,et al.  Unsteady simulation of viscous flowfield around F-18 aircraft at large incidence , 1992 .

[49]  R. E. Maine,et al.  Programmer's manual for MMLE3, a general FORTRAN program for maximum likelihood parameter estimation , 1980 .

[50]  Stephen A. Whitmore,et al.  A preliminary look at techniques used to obtain airdata from flight at high angles of attack , 1990 .

[51]  C. F. Smith,et al.  Comparison of the F/A-18A inlet flow analysis with flight data. II , 1996 .

[52]  Joseph W. Pahle,et al.  Research flight-control system development for the F-18 high alpha research vehicle , 1991 .

[53]  Detlef Rohlf,et al.  X-31A System Identification Using Single-Surface Excitation at High Angles of Attack. , 1996 .

[54]  Lee R. Peron,et al.  Thrust vectoring for lateral-directional stability , 1992 .

[55]  Larry A. Meyn,et al.  Full-scale high angle-of-attack tests of an F/A-18 , 1992 .