GB137257A - Improvements in course setting and navigating instruments for aircraft - Google Patents

Abstract

137,257. Pollen, A. H., and Landstad, H. F. Aug. 12, 1919. Aeronautical compasses; bearings and courses, indicating and determining; navigational calculation apparatus. - Relates to navigating compasses for aircraft of the type described in Specification 127,032, and comprises a compact arrangement of wind, air, and ground speed linkages and of the corresponding indicators. The air-speed vector is set up from the drum D by means of a pinion D<2> and rack D<3> on a slide F moving along the fore- and-aft line of the aircraft, the horizontal projection of the distance B<2>F<2> representing this speed The pivot B<2> is the centre of rotation for the compass, and the sleeve F<2> is attached to a table W<5> carrying guides W<15> within which moves the block W<16> positioning the pin D<6> on the slide D<4>. By means of the handle C' the compass bowl B is then turned to set a pointer on it in the direction of the wind. At the same time bv gearing, part of which is shown by W<10>, W<8>, W<7>, Fig. 3, the table W<5> is caused to turn to the same extent so that the guides W<15> are parallel to the wind's direction. Then, from the handle W<2>, Fig. 4, through bevelgearing W<22>, W<21>, W<19>, W<18> the screw W" is actuated to set the pin P<6> so that P<6>F<2> represents the wind-speed vector. B<2>P<6> then represents the ground speed and the sights parallel to the slide D<4> show the drift. A measure of the ground speed is given by means of a wire or band G<5>, Fig. 4, attached to a pulley G<6> on a pinion G<3> gearing into internal teeth G<2> on a graduated drum concentric with the compass bowl, the other end of the wire being attached to the support for the pin D<6>. Positioning of the pin P<6> sets the drum against a fixed pointer. An arm extending from the side of the casing forms a sight-hole well above and central to the compass to facilitate reading. A movable lubber line may be provided.