SLANT RANGE TRACKING TERRAIN AVOIDANCE SYSTEM

摘要

11. In combination with an aircraft, a slant range tracking monopulse radar on said aircraft for producing a range signal proportional to slant range to ground along a boresight axis extending forward of said aircraft at a relatively small depression angle, said radar including an antenna defining said boresight axis, means for sensing angle of attack of said aircraft, means responsive to said sensing means for stabilizing said antenna relative to the flight path of said aircraft, means for generating a reference signal proportional to nominal slant range to a point at a predetermined distance below said flight path, first comparator means responsive to said range and reference signals for producing a first control signal proportional to the difference therebetween, a vertically directed altimeter producing a measured elevation signal, means for generating a second reference signal proportional to a nominal elevation, second comparator means responsive to said elevation and second reference signals for producing a second control signal proportional to the difference therebetween, an aircraft elevation control divice, switch means for alternatively coupling said first or second control signals to said control device, a peak rectifier providing a first signal path between said first comparator means and said switch means, a delay device providing a second signal path between said first comparator means and said switch means, said radar including means for generating a range gate, on-target means for detecting coincidence of said gate and a signal received by said radar, and means responsive to said on-target means for operating said switch means to couple said first control signal to said control device when said coincidence is detected and to couple said second control signal to said control device when said coincidence is absent.