Plessey Avionics and Communications
N.B. this is part of Plessey Co
of Ilford, Essex.
1972 Awarded contract by Ministry of Defence for shipborne multi channel communication systems
1973 Plessey Avionics and Communications was at Upminster, Essex
1974 Managing director F. K. Chorley; sales manager avionics M. I. Dodd.
Airborne UHF/VHF transmitter/receivers: PTR175, PTR377, PTR1721 and PTR170 (UHF only); airborne integrated data acquisition and recording systems including advanced large-capacity PV740 system for the Boeing 747, PV1573 system for ARINC 573 for Concorde and wide-bodied aircraft and comprehensive flight-test systems; aircraft weapon control and stores management systems; missile guidance systems; radar altimeters; target aircraft telecommand systems. 
1986 Plessey Avionics, of Havant, announced the Plessey Automatic Launch Test Facility would be installed at all RAF stations to check every aircraft's friend/foe identification system was working at take-off
1989 Plessey Avionics announced a computer-based inflight entertainment and telephone system which it was offering to major airlines with no capital expenses by the airlines and profits shared; the idea has originated with a company called Candlestar and had evolved from military hardware
Later see GEC-Plessey Avionics
Sources of Information
- The Times Jan. 21, 1972
- Commerce Today Coming Developments in Business and Technology 1973-02-19
- FLIGHT International, 29 August 1974
- The Times Apr. 8, 1986
- The Times Sept. 1, 1989