In-flight transport performance optimization: an experimental flight research program and an operational scenario

A flight research program exploring the practical application of real-time performance optimization based on aircraft measurements and calculation of incremental drag from forced-response maneuvers is presented. The outboard ailerons of the L-1011 test bed aircraft were modified to provide for symmetric deflections to permit a recambering of the wing in that localized area, which in turn modifies the entire wing load distribution. The National Aeronautics and Space Administration developed an onboard research engineering test station from which the flight experiments are conducted and all analyses, both qualitative and quantitative, are performed in a real-time or near real-time manner. Initial flight test results are presented that indicate real-time drag minimization is attainable. An approach to an operational implementation of adaptive performance optimization on current and future commercial and military transports is discussed with the goal of keeping the required modifications simple and the pilot interface minimal and user friendly.