There has been a recent upsurge in the development of electric vertical take-off and landing (eVTOL) and electric short take-off and landing (eSTOL) aircraft for Urban Air Mobility (UAM) applications. These vehicles center on the use of Distributed Electric Propulsion (DEP) and offer several benefits in terms of faster, safer, quieter, more efficient and environmentally friendly transportation of passengers and goods. These vehicles are nonetheless complex to design, due, amongst others to the greater number of control effectors present relative to traditional fixed- and rotary-wing aircraft. In addition to conventional control surfaces, each propeller can act as a control effector that influences aircraft dynamic behavior. Control effector actuation stems from flight control laws that are developed after the aircraft design has been finalized. As such, flight control laws are not currently accounted for in the aircraft design process. Inclusion of flight controls within multidisciplinary design optimization (MDO) of DEP aircraft can result in more efficient and novel designs. The proposed effort aims to develop a modular MDO software framework for DEP aircraft design that will couple flight controls together with key disciplines such as aerodynamics and structures to meet this need. Resulting designs will leverage the inclusion of open- and closed-loop flight control parameters in the optimization to tailor aircraft sizing and performance. A prototype framework will be developed to demonstrate proof of concept in Phase I. An application case study using notional DEP aircraft configuration as baseline will be performed to demonstrate tool viability and assess efficiency.
The development and application of the proposed tool will directly support NASA’s ARMD Strategic Thrust #3 “Ultra-Efficient Subsonic Transports” and Strategic Thrust #4 “Safe, Quiet, and Affordable Vertical Lift Air Vehicles” since the inclusion of flight controls in DEP aircraft design is expected to produce novel, efficient, and cost-effective vehicle designs for both long-haul transportations, as well as inter- and intra-city UAM applications.
CDI provides engineering services and licenses software to multiple eVTOL companies and industry teams responsible for engineering analyses of large-scale DoD Future Vehicle Lift (FVL) aircraft development programs. The proposed capability will be of immediate use to these entities and will significantly reduce the number of design iterations in their aircraft design cycles.