Distributed propulsion

[1] Anticipated benefits include improved fuel efficiency, emissions, noise, landing field length and handling.

[6] The advantages of distributed propulsion for lightweight, high aspect ratio solar-powered aeroplanes are exemplified in the AeroVironment HALSOL/Pathfinder/Helios projects, begun in 1983, and the University of Michigan X-HALE, flown from around 2012.

[7] Distributing the electric motors along the span was able to control how the airframe flexed in flight, allowing the structure to be much lighter than the conventional rigid equivalent.

[4] FanWing began development of the crossflow fan as a combined lift and propulsion system in 1997 and over the next few years flew several models and research drones.

Subsequent research in the US focused on the use of a crossflow fan inset into the wing upper trailing edge, as the primary driver for boundary layer control and jet flap propulsion.

[3] More recently, several unmanned aerial vehicle (UAV) projects have explored the potential of distributed propulsion to offer noise abatement, fuel efficiency and short-field performance.

As of 2022 a manned X-plane, the X-57 Maxwell is under development at NASA and several prototypes of a light aircraft, the Lilium Jet, have flown in Germany.