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).
Comparison of the 'Condor', 'Eagle', and 'Falcon' aero engines against the Napier 'Lion' engine.
| Identifier | ExFiles\Box 180\M3\M3.3\ img023 | |
| Date | 22th October 1920 | |
| To Ho. from R.{Sir Henry Royce} Copy to CU: HOR BS{A J. Barnes - Assistant Manager} HS{Lord Ernest Hives - Chair} HP Handwritten notes: mainly wishfull thinking, the engine designed by R.{Sir Henry Royce} Royce was a much better engine (all round) than any of theirs. Fortunately for RR Royce rejoined RR in 1921. ORIGINAL! alone 5 Stamp: RECEIVED 25. OCT 1920 X.1900 X.3254 X.3155 RE "CONDOR" AND OTHER AERO ENGINES. The "Condor", and also our "Eagle" and "Falcon" should in some respects, be better than the Napier "Lion", because our engines are better balanced and therefore do not cause vibrations to themselves, their fixings, or the aeroplane, and for this reason, they should be more reliable. It is difficult to believe that the difference in the weight per H.P. is the real reason for preferring the Napier "Lion". Our impression is that on the total weight of the aeroplane any such slight amount may exist would not count, but what does count is that the Napier engine gives more H.P. than ours, and this H.P., if the plane is suitable, enables it to put up a better performance. Therefore we could, if we had an engine of the same H.P. put up the same performance, independent as to whether there was a slight difference in the weight of the engine. In our engines we give a reduction gear which does not put any weight on the crankshaft bearings or cause any wear to these bearings. We have now converted the anchorage of the sunwheel to a friction device which reduces the risk of torsional vibration occurring through any speed or period the engine may be running. It should be remembered that our engines were designed and built under urgent War conditions, and have not been seriously modified since the War. R.{Sir Henry Royce} | ||