F/A-18 Autonomous Formation Flight Control System Design

Abstract

Flight control system design for two F/A- 18 aircraft flying in closed-coupled formation is the subject of this paper. Developed by Boeing - Phantom Works as an integral part of NASA revolutionary concept program called Autonomous Formation Flight (AFF), the Formation Flight Control System (FFCS) provides autonomous aircraft operation and flight testing capability. Using two specially instrumented Boeing-built F/A-18 Hornets research aircraft, AFF Phase I flight demonstrations are scheduled for the fall of 2002 at NASA's Dryden Flight Research Center, Edwards Air Force Base, in California. It is expected that the trailing aircraft equipped with FFCS would sustain 15-20% drag reduction if it is flown in the wake vortex created by the lead aircraft wingtips. This paper presents the baseline FFCS design, analysis, and evaluation using high fidelity 6-DoF nonlinear aircraft simulation environment. Aircraft vortex modeling is discussed. An alternative adaptive formation flight control system design is proposed. The adaptive system is shown to improve the formation tracking performance.