Patent US 4,044,975

A system for displaying to the pilot an indication to enable him to fly to a desired air speed and angle of attack, especially on takeoff. An artificial angle of attack error signal is generated from actual and desired air speeds and corrected by adding to it a differentiated pitch signal. The resultant calculated angle of attack error is displayed to the pilot unless flying to that indication would result in exceeding the actual maximum or minimum angle of attack limits, in which case an indication based on the actual exceeded limit is displayed.