|RB199 Main Engine Control Unit
|Marconi-Elliott Avionic Systems Ltd
|Year of Manufacture:
Width (mm): 194
Height (mm): 197
Depth (mm): 454
Weight (g): 12,580
|Rack RAA01 [Main Store]
Two of the RB199 engines are fitted to the Tornado and provide outstanding performance. In order to meet the many different mission requirements of the Tornado, in particular extreme low-level missions, a 3-shaft design with afterburner and thrust reverser was selected. Each engine is controlled by a Main Engine Control Unit (MECU)which reduces the pilot’s workload during operation and supports on-condition maintenance. The MECU has two independent lanes of dry engine control and a single reheat control lane.
The original design of the MECU was by Rolls Royce but they gave the production contract to Lucas Aerospace but according to Flight International (14th May 1977) it appears that Lucas went in for ambitious advanced avionics, while the schedule required Turbo-Union to produce a flight cleared box for the Vulcan flying testbed early in the programme and later for the Tornado. During that period, 1973-74, Turbo-Union commissioned a fall-back system from Marconi-Elliott.
The Marconi-Elliott prototype system was highly regarded and did what it promised to do,whereas the Lucas equipment was less sophisticated but had done substantial flight testing and which was a lower risk when developed to high electronic standards for service use. It was a choice between the low-hour, advanced box or the more tested prototype. So the Lucas item was selected and subsequently improved.