Total energy based flight control system

An aircraft longitudinal flight control system for automatically controlling the aircraft's flight path and speed using engine thrust and elevator control surface position, comprising:

• means for developing an incremental thrust command signal .DELTA.T.sub.c which is a linear combination of a signal representative of the aircraft's total energy error with respect to the flight path and speed command targets and a signal representative of the rate of change of the aircraft's total energy;
• thrust control means for automatically controlling the incremental thrust to said incremental thrust command signal .DELTA.T.sub.c such that said total energy error is reduced to zero;
• means for developing an incremental elevator command signal .DELTA..delta..sub.e.sbsb.c which is a linear combination of a signal representative of the aircraft's total energy distribution error with respect to the flight path and speed targets, a signal representative of the rate of change of the total energy distribution, and pitch control damping signals;
• and
• elevator position control means for automatically controlling the incremental elevator position to said incremental elevator command signal .DELTA..delta..sub.e.sbsb.c such that said aircraft's total energy distribution error is reduced to zero.

An automatic flight control system for controlling an aircraft's vertical flight path and speed, comprising:

• means for developing a flight path angle command signal .gamma..sub.c for guiding the aircraft to, or holding the aircraft on, a desired vertical flight path;
• means for developing a longitudinal acceleration command signal V.sub.c for guiding the aircraft to, or holding the aircraft on, a desired speed;
• means for providing signals representative of the aircraft's vertical flight path angle .gamma. and longitudinal acceleration V;
• means for simultaneously processing said .gamma..sub.c, .gamma. and said V.sub.c, V signals to produce an incremental net thrust command signal .DELTA.T.sub.c and an incremental elevator command signal .DELTA..delta..sub.e.sbsb.c, said .DELTA.T.sub.c and .DELTA..delta..sub.e.sbsb.c signals being related to the aircraft's total energy error and total energy distribution error, respectively, with respect to the flight path and speed command targets, and said .DELTA.T.sub.c and .DELTA..delta..sub.e.sbsb.c signals coordinated in time and in magnitude to provide decoupled vertical flight path and speed command control;
• means for receiving the incremental thrust command signal .DELTA.T.sub.c and controlling the net thrust of the engines in response thereto;
• and
• means for receiving the incremental elevator command signal .DELTA..delta..sub.e.sbsb.c and controlling the elevator position in response thereto.

An automatic flight control system for controlling the aircraft's vertical flight path and speed, comprising:

• means for developing a flight path angle command signal .gamma..sub.c for guiding the aircraft to, or holding the aircraft on, a desired flight path;
• means for developing a longitudinal acceleration command signal V.sub.c for guiding the aircraft to, or holding the aircraft on, a desired speed;
• means for providing signals representative of the aircraft's vertical flight path angle .gamma. and longitudinal acceleration V;
• means for developing a signal E.sub.s.sbsb..epsilon. representative of the specific total energy rate error, where E.sub.s.sbsb..epsilon. =(.gamma..sub.c -.gamma.)+(V.sub.c -V)/g and a signal D.sub..epsilon. representative of the energy rate distribution error where D.sub..epsilon. =-(.gamma..sub.c -.gamma.)+(V.sub.c -V)/g;
• automatic thrust control means for controlling the net thrust in linear proportion to the time integral of said E.sub.s.sbsb..epsilon. signal;
• automatic elevator position control means controlling the elevator position in linear proportion to the time integral of said D.sub..epsilon. signal;
• said simultaneous thrust and elevator control causing the flight path and speed to track the commanded flight path and speed.

An automatic flight control system for controlling an aircraft's vertical flight path and speed, comprising:

• means for developing a flight path angle command signal .gamma..sub.c and a longitudinal acceleration command signal V.sub.c for guiding the aircraft to, or holding the aircraft on, a desired flight path and speed;
• means for providing signals representative of the aircraft's flight path angle .gamma. and longitudinal acceleration V;
• means for developing an incremental thrust command signal .DELTA.T.sub.c by forming a linear combination of the time integral of the aircraft's specific total energy rate error signal E.sub.s.sbsb..epsilon., where E.sub.s.sbsb..epsilon. =(.gamma..sub.c -.gamma.)+(V.sub.c -V)/g and the specific total energy rate signal E.sub.s, where E.sub.s =.gamma.+V/g:
• ##EQU16## and means for developing an incremental elevator position command signal .DELTA..delta..sub.e.sbsb.c, by forming a linear combination of the time integral of the aircraft's energy rate distribution error signal D.sub..epsilon., where D.sub..epsilon. =-(.gamma..sub.c -.gamma.)+(V.sub.c -V)/g and the energy rate distribution signal D, where D=-.gamma.+V/g:
• ##EQU17## thrust control means for coupling said incremental thrust command signal .DELTA.T.sub.c to the engine and controlling the thrust thereto;
• and
• elevator position control means for coupling said incremental elevator command signal .DELTA..delta..sub.e.sbsb.c to the elevator and controlling the position thereto.