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).
Speedometer reading 6% slow on a trials car (46-PK) due to temperature error, recommending a duralumin cup.
| Identifier | ExFiles\Box 29\3\ Scan158 | |
| Date | 6th September 1927 | |
| To Hm.{Capt. W. Hallam - Head Repairs} To BY.{R.W. Bailey - Chief Engineer} } FROM Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} 4788 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}4/LG6.9.27. c. to EP.{G. Eric Platford - Chief Quality Engineer} Mx.{John H Maddocks - Chief Proving Officer} Roy.{Sir Henry Royce} C. A.T. SPEEDOMETER. X4308 In our recent test of a trials car (46-PK) on Brooklands, we observed that the speedometer was reading about 6% slow. We consider that this was due to the temperature error of the instrument as explained in our Hs{Lord Ernest Hives - Chair}/RmL/LG13.7.27. We recommend that all speedometers fitted to trials cars should be equipped with the latest type of duralumin cup which obviates this error. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||