GB746575A - Improvements in or relating to air or dive brakes for aircraft - Google Patents

Abstract

746,575. Aircraft airbrakes. BLACKBURN & GENERAL AIRCRAFT, Ltd., FENTON, G. B., and BRUMBY, H. June 24, 1954, No. 18598/54. Class 4. An aircraft airbrake comprises at least two members which normally form a rear continuation of the fuselage and are each forwardly pivotally connected to a linearly movable part, with a link normally lying in a recess in the outer surface of each member pivotally connected to such member and to a fixed point of the fuselage, such that on rearward movement of such part the members are swung out by divergent translational movement into laterally extending operative positions. Fig. 3 shows the normal position in full lines, and the extended position in broken lines. Two links 5 and 6 are pivoted to fixed structure 40 and to the surfaces 1 and 2 which are also pivoted to a common member 4 slidable between guides 12, 13 by a jack 15, so that extension of the jack moves member 4 rearwardly to extend the surfaces. Guides 12 and 13 are braced by members 9 and 10, and the pivot point of links 6, 6 on the surfaces is chosen so that on failure of the jack, the surfaces close under the action of the air stream. The surfaces may be provided with extensions 18 which in the retracted position come together to form fins 41, and which in the extended position increase the area of the surfaces. Such fins may be exchangeable for fins of different size. The links lie in recesses in the surfaces when in the retracted position. Locking mechanism may be operated by the jack, and an indicator may inform the pilot when the brake surfaces are properly retracted. A further embodiment, Figs. 6-8 (not shown), has four symmetrically disposed surfaces, each having its own pivotal axis on a common cross-member slidable by a jack as above.