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).
Three functional checks for a device and urging for improvements to ensure its reliability.
| Identifier | WestWitteringFiles\T\January1929-February1929\ Scan176 | |
| Date | 22th February 1929 guessed | |
| (3) We should make sure that: (A) The motor stops turning the engine when the press button is freed. This is ensured by the two way press button even if the mechanical interlock is wrongly set as in one of the early specimens. (B) That the motor pinion does not stick in contact with the flywheel ring but that on breaking the circuit at the press button it always returns fully to its proper position of rest. (C) That the press button and magnetic switch work freely and with vigour, so that they break their respective circuits surely and with vigour. Any of these three faults would cause much inconvenience and trouble. Naturally you will look to these points, but I want it to be of great reliability. By the way our three specimens have worked I have ceased to be seriously anxious about this device, but you must work hard to get the best proportions at an early date so that they can be on the next 10,000 mile SSs. R.{Sir Henry Royce} | ||