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).
Test report on an A.T. Speedometer following a 10,000-mile run, investigating an increase in readings.
| Identifier | ExFiles\Box 59\2\ Scan049 | |
| Date | 11th July 1930 | |
| X4308. 11.7.30. X.4308. A.T. SPEEDOMETER NO. A.677 N.800 14/52 EX 10,000 MILE TEST CHASSIS 23-EX. This instrument has again been tested subsequent to the 10,000 mile run on 23-EX. Driven at 600 R.P.M. it has now been found to give the readings recorded on the attached sheet dated 9.7.30. It will be seen that these figures are considerably in excess of the figures previously obtained on sheet dated 27.1.30, the amount of increase at 30°C. being no less than 15.9%. Is this increase of reading purely due to a decrease in the main spring control or is it possible that the instrument may have been altered? Later. GWH.{George W. Hancock - Head Chateauroux} says instrument has not been touched. The only conclusion appears to be therefore that the spring control has altered. EFC. | ||