GB1206849A - Attitude and displacement indicator for aircraft - Google Patents

Abstract

1,206,849. Attitude and displacement indicator for a flight craft. BENDIX CORP. 22 Aug., 1968 [1 Sept., 1967], No. 40223/68. Heading B7W. An attitude and displacement indicator for a flight craft comprises a sphere 4, mounted for movement about axes X-X in accordance with displacement of the craft from a first predetermined reference, for example a localizer beam, for movement about axes Y-Y in accordance with the pitch attitude and for movement about axes Z-Z in accordance with the roll attitude of the craft; a band 12, positioned on the sphere, mounted for movement with the sphere about axes Y-Y and Z-Z, and for movement about axes X-X and Y-Y independent of the sphere in accordance with the displacement of the craft from a second predetermined reference for example a glide slope beam; the sphere 4 and band 12 being effective for indicating the pitch and roll attitude of the craft and the displacement of the craft from the first and second predetermined references. The indicator comprises a case 2 with a hollow sphere 4 mounted in it and divided into two hemispherical cups 6 and 8 by a painted horizon line 10. Centre band 12 with its axis in a horizontal plane is positioned around the sphere 4 and carries a symbol 14 representing the centre of glide slope and localiser beams. A symbol 16 representing the aircraft is fixed to the viewing aperture of the case 2 and flight director steering bars 18 and 20 are provided to give pitch and roll steering commands. The arrangement is such that the sphere has unlimited motion about axes ZZ and YY, and cups 6 and 8 and the centre band 12 have limited motion about the XX and YY axes respectively. Details are given of the mounting of the entire mechanism which is roll stabilized relative to the earth horizon. The indicator may be used in approach and landing mode of flight or in cruising flight. During the approach and landing the displacement symbol 14 moves vertically on the centre band to indicate the deviations from the glide slope beam and horizontally for deviations from the localizing beam. In cruising the sphere is rotated about the localizer displacement axis XX to remove the centre band 12 and the displacement symbol 14 from the viewing aperture of the case. The sphere is marked with a vertical scale (17), Fig. 5 (not shown), which, with the fixed aircraft symbol 16 indicates the pitch. The flight director steering bars 18 and 20 are arranged to move vertically in accordance with pitch command and about the ZZ axis in accordance with roll commands so that the pilot aligns the bars with the fixed symbol to place the craft on the desired flight path. In another embodiment the centre band may carry a reference mark corresponding to the level of the ground and be driven about the YY axis to indicate height above the ground.