From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
On gear reduction for aero engines, contrasting epicyclic and spur gears, and detailing the Eagle XVI design.
| Identifier | WestWitteringFiles\N\October1925-December1925\ Scan52 | |
| Date | 28th October 1932 | |
| (2) be considered by us now as it would result in serious modifications if they were not foreseen. We are also arranging for the engines to be runnable with and without the supercharger. Regarding gear reduction for aero engines I have the impression that the epicyclic gear is preferable to the spur gear for reasons too numerous to discuss here. In the gear we are designing for the Eagle XVI., which we fear will be required for long distance bombers, etc, and all but the fastest fighting and racing aeroplanes, we are arranging for a much more substantial annulus with coarser gears, the pinions being more narrow than in our Eagle design, and with plain pressure lubricated loose bushed bearings for the planetery system. We are also arranging in the gear (reduction) design for space for the gun gear driven direct from the propeller shaft. R.{Sir Henry Royce} [Stamp: RECEIVED 28 OCT 1932] | ||