In this paper the UAV close formation flight control problem is addressed. Formation flight involves controlling multiple wing aircraft to maintain a desired position relative to a lead aircraft throughout formation maneuvers. The formation consists of a lead and wing aircraft, where the wing flies in close formation with the lead, such that the lead’s vortices produce aerodynamic coupling effects. The nonlinear kinematic of formation was modeled in the wing’s Rotating reference frame. A proportional plus Integral controller is developed. It is shown that formation hold autopilots designed with the aerodynamic coupling effects ,yield satisfactory performance in close formation flight.