Rolls-Royce RB401
The RB401 was business jet engine which Rolls-Royce started to develop in the mid-1970's.
RB401-06 prototype engines were already being manufactured when a decision to develop the higher thrust RB401-07 was taken.
Although the basic configurations of both engines were almost identical, the -07 variant had a larger fan diameter. A single stage fan, driven by 2 stage LP turbine, supercharged an 8 stage HP compressor, driven by a single stage transonic HP turbine. The combustor was annular and the co-annular exhaust featured a lightweight target type thrust reverser.
Leading particulars for -07 variant were as follows:
Fan Diameter: 32.4in
Take-off Thrust: 5540lbf, flat-rated to ISA+15C
Cruise Thrust: 1128lbf (Mach 0.7, 40000ft, ISA+10C)
Although ground testing of both the -06 and -07 continued into the early 80's, a lack of funds caused the project to be cancelled.