GB1181991A - Aircraft Lift-Increasing Device - Google Patents

Abstract

1,181,991. Aircraft aerofoils. E. M. LANIER. 14 April, 1967, No. 17306/67. Heading B7G. [Also in Division F2] An aircraft aerofoil 16 has at least one closable passage 18 therethrough, the passage being converging from, and rising upwardly and rearwardly from an inlet on the lower aerofoil surface, the passage being defined by a fixed front wall and a rear wall 63 movable from a closed position, Fig. 1, in which both ends of the passage are closed, and a passage open position, Fig. 2, in which a lower portion 62 of the rear wall forms a scoop projecting below the lower surface of the aerofoil, there being a flap 74 pivoted on this lower portion which moves from a closed position flush with the aerofoil, Fig. 1, to an open position projecting below the scoop. Fig. 2. There may be a further flap 29 on the upper aerofoil surface, and a further converging passage 17 further forward on the aerofoil. The movable rear wall may comprise a flexible surface 63, 53 of which the upper part is pulled open by a link 66, 58, the lower part only being attached to ribs 64, 43 which pivot at 66, 56 to open the inlet of the passage. The scoop 62 and the flap 74, Fig. 4, both assist in increasing the airflow through the passage, where it is accelerated and then added to the boundary layer on the upper aerofoil surface. It is stated that an aircraft with wings of a cross-section as shown flew at 19 miles per hour without loss of height. Actuation,-The linkage may be controlled by torque tubes 19, 21 which in turn control either rods, as shown, or cables, and/or possibly hydraulic circuitry or electric servomotors. Actuation of torque tube 21 alone will move spoiler flap 29 only (by links 23 and 28), the compensatory mechanisms 24, 26 imparting no movements to arms 47, 69 until arms 46, 68 are moved by torque tube 19. Movement of torque tube 19 opens both the passages 17, 18, the throat of the front passage 17 being controlled by link 34, bellcrank 36 and link 58, and link 32, crank 33 and link 42 controlling the movement of rib 54 pivoting at 56, links 34, 37 transmitting control to similar linkages for the rear passage 18. As the front passage is opened crank 33 transmits via rod 44 a movement to arm 46 of the compensating mechanism 24. This transmits a portion of this movement to arm 47, the portion depending on the position of arm 31. Movement of arm 47 controls flap 57 by link 48, bellcrank 49 and link 51. The rear flap 74 is similarly controlled via compensating mechanism 26.