Of three series of flaps, the upstream series having its flaps hinged

Official title: {of three series of flaps, the upstream series having its flaps hinged at their upstream ends on a fixed structure and the internal downstream series having its flaps hinged at their downstream ends on the downstream ends of the flaps of the external downstream series hinged at their upstream ends on a substantially axially movable structure}

F02K1/1284 (Of three series of flaps, the upstream series having its flaps hinged) appears on 2 US grants and 1 published applications in this corpus.