A leading-edge droop flap comprises the rounded front part of a wing, in movable form. The Airbus A380 has droop flaps between the fuselage and each inboard engine, at the leading edge of the thickest part of each wing.[1][2] Early variants of the Hawker Siddeley Trident had two droop flaps on the outboard of each wing and a Krueger flap on the section closest to the fuselage.[3]