The B-1B has a "variable-geometry" or swing-wing design: The wings are swept forwards, almost at right angles to the body, for take-off and landing and cruising.

BBC: Profile: B-1 bomber

Its wings not only beat up and down, but also twist at specific angles.

FORBES: Festo Builds a Robot Bird

Glasgow's best offensive options lay out wide in the pace of Evans and the fine angles being cut by Hefin O'Hare, but the visitors struggled to get the ball to the wings with any space to work in.

BBC: Cardiff Blues 27-9 Glasgow