The subject of automatic formation flight control is of current interest to the development of Unmanned Aerial Vehicles (UAV). Previous control approaches have been refined in this work to allow more robust maneuvering and to include a fourth control parameter. The equations of motion for each aircraft as a point mass, expressed in a wind-axis coordinate system, are coupled into differential equations that model the two aircraft system dynamics. Control laws are developed that include proportional and integral action. Gains are determined based on formation performance. Lead maneuvers are simulated and the controller is gauged on its ability to maintain the commanded formations in and out of the vortex wake generated by the lead aircraft. A Dryden wind model at varying intensities is applied to the system. In simulation the controller maintained acceptable performance in all maneuvers tested. A slightly modified controller was applied to a USAF NF-16D aircraft for flight testing. Utilizing a data link system and a virtual lead aircraft generated from a ground based control station, the NF-16D was able to flight test the controller. In-flight, the controller was stable, and able to perform all of the desired formation hold and change maneuvers.