Aeronautics and astronautics – Aircraft control – Automatic
Patent
1997-11-04
1999-11-09
Barefoot, Galen L.
Aeronautics and astronautics
Aircraft control
Automatic
244195, 701 8, B64C 1306
Patent
active
059798351
ABSTRACT:
Disclosed is a pitch-axis stability and command augmentation system (19) in which a pilot column input (.delta..sub.C) is provided to a pitch command processor (26), the output of which is a C*U feedforward command (C*U.sub.FFC) that is supplied as an additive input to a combining unit (20). The combining unit (20) receives a second additive input of an augmented feedback command signal (AFB.sub.COM). The resulting output is filtered and generates an elevator command signal (.delta..sub.e,FILT). The command processor (26) additionally supplies a corrected column position signal (.delta..sub.C,COR) to a pitch command C*U processor (26) that converts the corrected column position signal (.delta..sub.C,COR) into a C*U pitch command (C*U.sub.PilotCmd), representative of the pilot's requested elevator pitch which is generated by movement of the control column. A computed C*U processor (32) forms a computed C*U signal (C*U.sub.Computed) that is based on the current state of the aircraft. The C*U processor (32) includes a speed stability processor (150) that computes the difference between a reference speed (V.sub.REF) and calibrated airspeed (V.sub.CAS). The speed stability processor (150) includes phugoid damping (400) in generating a speed error signal (E.sub.z), and providing a means by which the pilot may set a reference airspeed (V.sub.REF) by using a trim device. An underspeed protection signal (C*U.sub.US) is supplied by a stall protection processor (416). A flare compensation signal (C*U.sub.FR) is supplied by a flare compensation processor (414). An overspeed protection processor (412) supplies an overspeed protection signal (C*U.sub.OS). A combining unit (424) is provided to combine the stall protection signal (C*U.sub.US), flare compensation signal (C*U.sub.FR), and overspeed protection signal (C*U.sub.OS) to form a compensation and protection signal (C*U.sub.C&P). A combining unit (22) combines the pilot-requested C*U command (C*U.sub.PilotCmd), the computed C*U signal (C*U.sub.Computed), and the compensation and protection signal (C*U.sub.C&P). The resulting signal is an error signal (E.sub.C*U) which is supplied to an integrator (28) that outputs a C*U integral command signal (IC*U.sub.COM). Another combining unit (23) receives the C*U integral command signal (IC*U.sub.COM) and combines it with a pitch rate damping command signal (Q.sub.COM). The output of the combining unit (23) is the augmented feedback command signal (AFB.sub.COM).
REFERENCES:
patent: 3345018 (1967-10-01), Chanak et al.
patent: 3911345 (1975-10-01), Totten
patent: 4261537 (1981-04-01), Tisdale et al.
patent: 4676460 (1987-06-01), Hagy et al.
patent: 4767085 (1988-08-01), Boudreau et al.
patent: 4849900 (1989-07-01), Blight et al.
patent: 4855738 (1989-08-01), Greene
patent: 5016177 (1991-05-01), Lambregts
patent: 5225829 (1993-07-01), Batemen
Blight et al., "Control Law Synthesis for an airplane with Relaxed Static Stability", Journal of Guidance, Control and Dynamics, vol. 9, No. 5, Sep.-Oct. 1986, pp. 546-554.
"A320 Fly By Wire and Handling Qualities", 5th Performance and Operations Conference, Airbus Industrie Engineering Directorate Flight Division, May 1988, 13 pp.
A320 Primary Flight Control Flight Crew Operating Manual Descriptiondate unknown, 6 pp.
Mooiji, H.A., et al., "Flight Test of Stick Force Stability in Attitude-Stabilized Aircraft", J. Aircraft, vol. 15, No. 9, pp. 562-566, Sep. 1978, 5 pp.
Hughes, D., "Extensive MD-11 Automation Assists Pilots, Cuts Workload", Aviation Week& Space Technology,Oct. 22, 1990, 9 pp.
Airbus Industrie, "The New Generation", Brochure, Ref. No. AI/EV-T 474.0338 BS, Issue 2, Dec. 1992, 60 pp.
Airbus Industrie, "Fly by Wire A300 Aircraft 3 Demonstration", Ref. No. AI/EC No. 048/86, Jun., 1986, 25 pp.
Corps, S.G. "Airbus A320 Side Stick and Fly By Wire--An Update", SAE Technical Paper Series, Aerospace Technology Conference and Exposition, No. 861801, Oct. 1986, 13 pp.
Wagner, G.A., "What Makes the A320 Different?", Pilot, pp. 24-32, Oct. 1988, 9 pp.
Tobie, H.N. et al. "A New Longitudinal Handling Qualities Criterion", The Boeing Company, date unknown, 7 pp.
Droste, C.S. et al., "The General Dynamics Case Study on the F-16 Fly-By-Wire Flight Control System", AIAA Professional Study Series, date unknown, 3 pp.
Bleeg Robert J.
Breuhaus Richard S.
Evans Monte R.
Najmabadi Kioumars
Barefoot Galen L.
The Boeing Company
LandOfFree
Aircraft pitch-axis stability and command augmentation system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Aircraft pitch-axis stability and command augmentation system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aircraft pitch-axis stability and command augmentation system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1445562