Studying and Optimizing the Take-Off Performance of Three-Surface Aircraft

Abstract

In the quest for making aircraft more energy-efficient, configuration, and primarily the arrangement and quality of aerodynamic surfaces, play a relevant role. In a previous comparative study by the authors, it was shown how to obtain a significant increase in cruise performance by adopting a three-surface configuration instead of a classical pure back-tailed design. In this paper, an analysis of the same configurations in take-off is carried out, to assess through a fair comparison the potential effect of a three-surface one especially on take-off distance. Take-off is mathematically described by means of a sound analytic approach. Take-off distance is computed for a baseline two-surface aircraft, and in a later stage on a three-surface one. In addition to exploring the performance, a numerical optimization is also deployed, so as to find the best use of both configurations analyzed (i.e., baseline and three-surface) in take-off, and the corresponding top performance. The quality of the optimum, as well as the practical realization of a control link between the yoke and both control surfaces in the three-surface configuration, are analyzed in depth. The paper describes the advantage which can be attained by selecting a three-surface configuration, and proposes some remarks concerning the practical implementation of the maneuver to actually capture an optimal performance.