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).
Discrepancy in the speedometer calibration for the Peregrine chassis.
| Identifier | ExFiles\Box 59\2\ Scan180 | |
| Date | 24th September 1932 | |
| X6051 BY/Cgh.{W Clough} from Hs{Lord Ernest Hives - Chair}/Wst. c. BY/RD. Hs{Lord Ernest Hives - Chair}/Wst.4/KT. 24.9.32. PEREGRINE SPEEDOMETER. We notice on the drawing of the above that the calibration instructed for the Peregrine chassis speedometer is 1000 revs/mile. According to our calculations, however, we make this figure 985, and the speedometer at present on the Peregrine chassis is calibrated to this figure. Road tests, and tests on Brooklands have shown that this speedometer is reading correctly to within the usual plus limits allowed. If speedometers are calibrated to the D.O. figure of revs/mile, they will read 1.5% slow, which is an undesirable feature. We should be glad if you would look into the question of how this apparent discrepancy has occurred. Hs{Lord Ernest Hives - Chair}/Wst. | ||