| Pennine | |
|---|---|
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|
| Type | X-24 air-cooled sleeve-valve piston aero-engine |
| Manufacturer | Rolls-Royce Limited |
| First run | 1945 |
| Major applications | Not flown |
| Number built | 1 |
| Developed from | Rolls-Royce Exe |
The Rolls-Royce Pennine was a British 46-litre air-cooled sleeve valve engine with 24 cylinders arranged in an X formation. It was an enlarged version of the 22-litre Exe; a prototype engine was built and tested, but never flew. The project was terminated in 1945, being superseded by the jet engine.
A 100-litre 5,000 hp X32 (twin-X16) version of the Exe/Pennine, originally known as the Exe 100, was to have become the Rolls-Royce Snowdon.
Rolls-Royce air-cooled engines, intended for commercial transport aeroplane use, were named after British mountains, e.g. The Pennines and Snowdon.