Moving Base Simulation of an ASTOVL Lift-Fan Aircraft

iii Nomenclature h altitude, ft ˙ h vertical velocity, ft/sec K fnt scale factor for lift from jet-induced fountain p roll rate, deg/sec q pitch rate, deg/sec r yaw rate, deg/sec T CN cruise nozzle thrust, lb T LF lift-fan thrust, lb T LN lift-nozzle thrust, lb T R rise time, sec V airspeed, knots V ej equivalent jet velocity ratio V x ground speed, ft/sec V y lateral velocity, ft/sec β sideslip angle, deg ∆L/T normalized jet-induced aerodynamic ground effect δ LF x longitudinal lift-fan deflection, deg δ LF y lateral lift-fan deflection, deg δ LN lift-nozzle deflection, deg δ lat lateral stick deflection, in. δ lon longitudinal stick deflection, in. δ N thrust deflection angle, deg δ ped pedal deflection, deg δ th power lever angle, deg φ bank angle, deg γ flightpath angle, deg ψ heading angle, deg θ pitch attitude angle, deg ACAH attitude command/attitude hold APP approach control mode ASTOVL advanced short takeoff and vertical landing ATM automatic transition control sub-mode CGI computer-generated imaging CTO cruise/takeoff control mode FPC flightpath command FTM full thrust command control sub-mode HQR handling qualities ratings HUD head-up display IGV inlet guide vane IMC instrument meteorological conditions MTV manual thrust vector control mode RC rate command RCAH rate command/attitude hold rms root mean square SCAS stability and command augmentation system SKP station-keeping point SS sea state STOL short takeoff and landing STOVL short takeoff and vertical landing TRC translational rate command control mode VC velocity command VMC visual meteorological conditions VMS Ames Vertical Motion Simulator V/STOL vertical or short takeoff and landing Summary Using a generalized simulation model, a moving-base simulation of a lift-fan short takeoff/vertical landing fighter aircraft was conducted on the Vertical Motion Simulator at Ames Research Center. Objectives of the experiment were to (1) assess the effects of lift-fan propulsion system design features on aircraft control during transition and vertical flight including integration of lift fan/lift/cruise engine/aerodynamic controls and lift fan/lift/cruise engine dynamic response, (2) evaluate pilot-vehicle interface with the control system and head-up display including control modes for low-speed operational tasks and control mode/display integration, and (3) conduct operational evaluations of this configuration during takeoff, transition, and landing similar to those carried out previously by the Ames team for the mixed-flow, vectored thrust, and augmentor-ejector concepts. Based on results of the simulation, preliminary assessments of acceptable and borderline lift-fan and lift/cruise engine thrust response characteristics were …