Air Transport

Delaying stall on a fixed-wing micro air vehicle (MAV) to enable it to perch is the focus of a three-year US Air Force Research Laboratory (AFRL)-funded study. The goal is to develop a wing that delivers high lift for low speed manoeuvrability.

Computer modelling and windtunnel tests will be used to understand how to replicate the leading-edge vortex phenomena that birds and insects exploit for high lift at low speeds. “We are trying to control dynamic stall. Being small is an advantage, as you get vortex stabilisation at low Reynolds numbers,” says Princeton University assistant professor of mechanical and aerospace engineering Clarence Rowley.

A delta wing produces a good leading-edge vortex, but with its low aspect ratio it has high drag at low speeds, he says.

ROB COPPINGER / LONDON