Jaguar Diagnostic Display Unit

Technical Information

Catalogue No: C0194
Category: Maintenance Systems
Object Type: Indicator/Instrument
Object Name: Jaguar Diagnostic Display Unit
Part No: 79-051-01
Serial No: 103
Manufacturer: Marconi Avionics
Division: Unknown
Platform(s): Jaguar FBW 
Year of Manufacture:
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Location: Archive Object Store

Marconi Avionics Limited
Diagnostic Display Unit
Part 79-051-01
Ser 103
Code K0656


The Jaguar was the result of an Anglo-French collaboration to develop an advanced training and strike aircraft, entering service with the Royal Air Force in 1973.
XX765 was withdrawn from RAF service to demonstrate the feasibility of Active Control Technology (ACT), under development by British Aerospace (BAe). The aircraft's normal control rods were replaced with a 'fly-by-wire' (FBW) control system, which used four independent computer-controlled electrical channels to relay instructions to the flight surfaces. The aircraft was further modified by fitting large leading edge strakes (wing extensions) to move the centre of lift forward and adding ballast to the rear fuselage to move the centre of gravity aft. This enhanced lift and drag characteristics and made the tail plane more efficient thereby allowing smaller lighter engines with greater fuel efficiency to be used, decreasing overall weight by 15%.
Flight trials began in October 1981. Test pilots were impressed by the crisp control responses and smooth flight. The aerodynamic instability of the aircraft enhanced manoeuvrability, but the computer-controlled flight commands provided split-second corrections to compensate for the unstable configuration.
The FBW Jaguar programme ended in September 1984 after 96 flights. The information gleaned was used in the development of the Eurofighter.
The Pilot's Controller & Switch Panel provides system status indication to the pilot. Status signals for the Flight Control Computers are consolidated to illuminate a ‘Status’ amber warning for a first failure or a similar red warning for a second failure. The pilot may attempt a reset when an amber warning is shown by pressing the ‘Status’ key but if a red warning is shown this reset is inhibited. The panel also carries the Autopilot Engage button, the BIT initiate button, a facility to initiate different control law gains and power switches to associate the supplies to the computers to enable pre-flight checks.

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