Object StatementAnalogue computer, Anti-Aircraft Predictor, Vickers No.1 Mk III, metal / glass, designed by Vickers Limited, England, 1924, made by Sperry Gyroscope, United States of America, 1942
Physical DescriptionThe Vickers Mk III Anti-Aircraft Predictor is an analogue computer designed for plotting the current position, course and speed of incoming aircraft as well as calibrate and aim anti-aircraft guns. The device consists of two metal cases, painted in military dark green, with the smaller bolted on to the top of the main section.
The upper section, has a panel of the right, marked 'COMPUTER HEIGHT A.A. No.1 MK I / GEC / 1942 / REG No 730 / O.S.19.M.A', and consists of a pipe input with a spring loaded cap and a series of, glass covered, ovular windows on the sides for viewing the inner workings of the computer which include a number of wires, small lights and a horizontal cylindrical calculator. Around the top edges there are a number of screw caps, which house small light bulbs.
The main body is square and rests on four solid, cylindrical, feet and can be divided into four panels, each serving a different purpose. The front panel, has a plaque in the centre, inscribed with 'PREDICTOR 3. 7 INCH H.A. No1 MK III / THE SPERRY GYROSCOPE Co Ltd 1941 / No 231', which can be opened to reveal the inner workings. Above this are two circular winders labelled 'TIME & FUZE' and 'TANGENT ELEVATION' as well as a number of gauges and small dials for 'WIND DIRECTION' and 'GUN HEIGHT'. The back panel is similar to the front and contains a series of circular dials, knobs and winders, in a diamond shape, inscribed with, 'LATERAL DEFLECTION IN AZIMUTH', 'VERTICAL RATE', 'LATERAL RATE' and 'VERTICAL DEFLECTION'. The two side panels each consist of a central telescopic sight, which can be adjusted along a 90 degree gauge, and have a metal cap, red rubber eye protector and an adjustable focusing gauge made from brass. The left side panel is used for adjusting bearing and features a circular slide on the right, indicating height in 1000 increments and a 'TRANSMITTED BEARING' gauge below, which can be adjusted using two rotating levers for normal and fast traverse. The right panel, used for calculating and adjusting elevation contains a small window for viewing inside the device and a circular gauge marked, 'QUADRANT ELEVATION' below. Positioned under the main body is a brass, 360 degree, disc, that is used to determine the correct positioning for the anti-aircraft guns.
A spare panel, which can be placed over the back side has four glass gauge covers and a series of cut outs to slot over the dials and knobs.