Method for Evaluating Electrically Actuated Hybrid Wing–Body Control Surface Layouts

Abstract

Hybrid wing–body configurations are currently an active field of research as potential candidates to meet NASA Environmentally Responsible Aviation goals. One characteristic of these configurations is the presence of a large number of redundant flight control surfaces. However, the design process and decision rationale for a given control surface layout is rarely discussed in the open literature. This work investigated tradeoffs between drag, control authority, actuator weight, and actuation power requirements as a function of the number and spacing of elevons. The actuators were sized based on hinge moments computed during nominal and failed control flight conditions. These effects were propagated upward to estimate changes to fuel burn, a system-level metric important to the Environmentally Responsible Aviation program, via the Breguet range equation. A model of the NASA N2A-EXTE hybrid wing–body configuration concept was used to demonstrate these tradeoffs. The study concluded that adjacent elevons could be combined to achieve reductions in weight, power usage, and fuel burn. This resulted in a reduced number of elevons from the baseline and unequal span fractions.