GB191506967A - Improvements in Pilot-steering Indicators for Aircraft. - Google Patents

Abstract

6967. Barr & Stroud, Barr, A., and. Stroud, W. May 10. Angle-measuring instruments.-Apparatus for indicating to the pilot of an aircraft the direction in which to steer in order to 8y in a vertical plane containing a target comprises a gyroscope W, Fig. 1, to the frame of which is fixed a collimator consisting of a curved slit S and a cylindrical lens G so arranged that an eye at E, by looking up or down, can see either the upper or lower part of the slit S, a view of the ground being seen simultaneously by means of a reflecting system, Fig. 2, comprising parallel mirrors M<1>, M<2> adjustable about the transverse axis V, the mirror M<2> being semi-transparent. The gyroscopic pendulum may be similar to that described in Specification 3318/15 and may be similarly driven by hand. The pendulum is constructed to have the minimum of friction about the axis L-L and to have damping friction about the axis T. The parallel M<1>, M<2> may be constructed of a single piece of glass, a prism being cemented over a partly silvered part of the mirror surface next to the eye in order to obtain a direct view of the ground. The cylindrical lens may be formed in two parts G<1>, G<2>, Fig. 6, inclined to each other to bring the various parts of the slot S more exactly into focus. In the arrangement shown in Fig. 6, the ground is viewed directly through the semi-transparent reflector R carried on the collimator frame. In another 'construction, Fig. 10, the cylindrical lens G has a long flat portion F polished upon it, through which the ground is viewed directly while the slot is represented by a wire or a line V on a sheet of glass.