GB457454A - Improvements in and relating to aircraft controlling surfaces - Google Patents

Abstract

457,454. Aircraft tail unit. BAYNES, L. E., 144, Cromwell Road, South Kensington, London. May 25, 1935, Nos. 15328 and 15329. [Class 4] An aircraft tail unit comprises a horizontal cantilever tail plane having a main and a subsidiary spar spaced apart at their roots and converging toward their tips where they are rigidly joined together, the spar roots being attached by quick release joints to the spars of a fixed fin. A fixed fin 4, Fig. 1, is built up on substantially vertical spars 2, 3 upstanding from the tail end of the fuselage 1, Fig. 2. Intermediate of its length spar 2 carries a spar root attachment comprising plates 8 extending outwardly on either side of the spar to engage similar fittings secured to main spar 6 of tail plane 7. Attachment is by upper and lower pairs of pins 9, 11. A similar fitting but providing for one securing pin on each side only, is carried by spar 3 and serves for securing rear spar 12. Spars 12 of the two tail planes are collinear. Elevators 16 are hinged to spars 12 by brackets 21, Fig. 4, embracing brackets 20 on the spars through which passes a torque tube 19. Spar 3 carries a shaft 23 adapted to mate with the ends of torque tubes 19 and to transmit rotation thereto through pins 25 engaging slots 26 formed in the tube ends. Fast on shaft 23 is a lever 27 connected by a substantially vertical link 28 to a bell-crank lever in the tail end of the fuselage and operatively connected to the pilot's elevator control. According to a modification, hinge pin 19 and operating shaft 23 may not be in alignment, a universal joint being incorporated in either or both of them so that they may be brought into local alignment for coupling together. Specification 432,301 is referred to.