Abstract: A guidance system is provided for flight vehicles which establishes a reference direction in space by means of two pulsed laser beams. The desired direction is remotely determined and an optical tracker on the flight vehicle is then gated ON by a first pulsed laser beam wih a fixed time delay following receipt of a pulse on board the vehicle. A second pulsed laser beam is fired in a direction to intersect the desired flight path at a set distance from the vehicle, and at a time such that a pulse of the second beam crosses the desired path, and returns to the missile during the time while the tracker on the vehicle is gated ON, so that the tracker receives energy from the backscatter from the atmospheric segment illuminated by the pulse, and causes the vehicle to travel in the desired direction.

Abstract: An angular acceleration aided system for electrooptical tracking of a designated target which operates independently of an inertial navigation system. The designated target point, as viewed by a gimbaled electro-optical sensor is portrayed on a video display where a human operator compensates for deviation in the tracking beam from the line-of-sight to the target by providing a rate command signal to the azimuth axis servo of the gimbaled sensor through a parallel combination of an integrator and an amplifier and, also, by providing a rate command signal to the elevation axis servo of the gimbaled sensor through a parallel combination of an amplifier and an integrator provided with a feedback circuit which establishes an acceleration aiding signal for the elevation axis.