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).
The efficiency of large propellers and why aeroplane engines run at lower speeds.
| Identifier | ExFiles\Box 147\5\ scan0047 | |
| Date | 2nd September 1913 | |
| R9/P 2.9.13. COPY. Sheet 4. is for this reason, and for the reason of the efficiency of the larger propellers, that the aeroplane engines are run at a much lower speed than what one would expect. R.{Sir Henry Royce} DICKINSON BOND 1804 MADE AT CROXLEY | ||