1,163,801. Aircraft flap actuating mechanism. BRITISH AIRCRAFT CORP. (OPERATING) Ltd. 30 Aug., 1967 [31 Aug., 1966], No. 38853/66. Heading B7G. On an aircraft wing 10 is mounted a slotted flap comprising a main flap 12 and a vane 13, which in the extended position provide slots between the wing and the vane, and between the vane and the flap, and are moved between this and a stored position by a mechanism comprising an actuator (e.g. screw jack 20 and pivoted nut 18a) to move the vane and a linkage connecting the vane to the flap to move the flap further than the vane, the wing having mounted thereon rollers 15 which engage a track unit 14 attached to the vane, the track unit also engaging rollers 16 on the flap. The track unit 14 may comprise a pair of S-section members joined by a member 18 to which are pivoted the nut 18a and the vane at 13a. The linkage may comprise an arm 27 pivoted to the wing at 31 along which slides a member 22 pivoted at 23 to the member 18, and at 24 to the links 25 pivoted at 26 to the flap 12. The linkage may be housed, when retracted, in a blister 11 on the underside of the wing.