The Demon system's success in controlling roll, one of the three axes of movement of a body in free space, is also leading engineers to wonder if the other two axes, pitch and yaw, might similarly be transferred to fluidic systems from, respectively, the elevator flaps on the tailplane and the rudder on the tail.

ECONOMIST: How to fly without ailerons

"Even clad in full winter gear, with ice-axes, winter boots and full waterproof body cover, it was a struggle, " said Mr Rodwell.

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