A learning adaptive flight control system was developed for stability augmentation of the longitndinal axis of the Fl0lB fighter aircraft. Design techniques described are generally applicable to a broad range of perfornance criteria and for a variety of control srstems problems including aircraft flight control. The design philosophy was adopted which required the use of three loops in the control system. The learning controller employs the strategy of long-term memory recall and selective reinforcement with the objective of maintaining relatively constant handling characteristics when the aircraft undergoes large variations in its system parameters due either to environment or to modification in the aircraft itself.