C-5 Air Data Computer

Technical Information

Catalogue No: C0158
Category: Air Data
Object Type: Signal/Data Processor
Object Name: C-5 Air Data Computer
Part No: 50-001-08
Serial No: 0001
Manufacturer: Elliott Bros
Division: Unknown
Platform(s): C-5A/B Galaxy 
Year of Manufacture: 1966
Width (mm):
Height (mm):
Depth (mm):
Weight (g):
Location: Archive Object Store

Computer Central Air Data, MC 0159A


This is an Air Data Computer from 1967 designed for the C-5A The Lockheed C-5 Galaxy is a large military transport aircraft built by Lockheed. It provides the United States Air Force (USAF) with a heavy intercontinental-range strategic airlift capability and has been operated by the USAF since 1969.
An Air Data Computer computes altitude, vertical speed, air speed, and mach number from sensor inputs such as pitot and static pressure and temperature. The early systems were electromechanical computers, and Elliotts backround wasas much in electronics as in precision gear making. After WWII Elliotts was acquired by Leon Bagrit who already managed Swift and Swallow on the Rochester site. During the Second World War the manufacturing company, styled B & P Swift Limited turned to war work, and manufactured aircraft equipment for the Ministry of Aircraft Production. This included flap and undercarriage actuators, which called for good gear and screw-cutting facilities and they also had a commercial arm making weighing scales which required gear wheels. Elliotts gained a precision gear capability and this can be seen in the early instruments such as this Air Data Computer,

An order for modular air data computers for British-built Jaguars, worth more than £250,000, was placed with Elliott Flight Automation by Mintech in1970. The unit was the smallest and lightest for its performance yet developed. A pre-production unit was flown in the S.06 prototype on its first flight in1969. The air data computer in the Jaguar forms a single central source of corrected signals of height, indicated airspeed, true airspeed, Mach number and related information, giving 16 different outputs for flight instruments, head-up display, navigation and weapon aiming. It also provides a digitised output of height for automatic altitude reporting through the secondary radar transponder. Individual functional modules can be replaced without recalibrating The mechanical transmission between modules also reduces weight and improves reliability.

The Air Data Computer was made lighter and smaller similar to the range of air data computers which were already being produced for the Nimrod, the American Lockheed C-5A heavy logistics transport, BAC One-Eleven, HS.748s for the Royal Australian Air Force and for the engine intake control system of the Concorde.

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