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).
Instruction to a tester to record barometric readings as they have a marked effect on engine power.
| Identifier | ExFiles\Box 37\3\ scan 126 | |
| Date | 13th September 1917 | |
| X.3178. Extract. Mr. Cliburn, Rolls-Royce's Tester, c/o Martinsydes, Byfleet, Surrey. 13.9.17 Dear Sir, In taking a record of the engine revs. from day to day it would be very instructive if you could obtain barometric readings. The height of the barometer has a marked effect on the power. There would be a difference of 10 or 11 H.P. in the power of your engine, if the barometer were 29" instead of 30". Although running against a propeller the lower the pressure the less the resistance there would be to the propeller, so that the revs should keep fairly constant. | ||