Integrated Optimization of Ailerons for Active Gust Load Alleviation

Abstract

An active gust load alleviation (GLA) system offers great potential for weight savings in aircraft design. Its effectiveness, however, strongly depends on the layout of available control surfaces, which is investigated in this paper. For the purpose of wing load reduction, the parameters of a static gain feedback controller are optimized simultaneously with aileron geometry parameters. Therefor, an efficient update routine for the nonlinear model of a largescale flexible aircraft, including unsteady aerodynamics, is presented. Compared to a GLA system using the original aileron configuration, 9% performance improvement is achieved. An additional study is carried out to quantify the necessary trade-off between individual load channels. Concluding, the significant influence of aileron size and position on overall GLA performance is clearly demonstrated and hence a consideration in preliminary aircraft design is strongly recommended.