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).
Brief resume on the performance of doped oil in aircraft engines.
| Identifier | ExFiles\Box 27\3\ Scan242 | |
| Date | 7th October 1939 | |
| 8 Rm.{William Robotham - Chief Engineer}1/MH.{M. Huckerby} 7th. October, 1939. O.W.Tweedie, Esq., Rooms 5 and 6, Grand Hotel, HARROGATE. Dear Tweedie, Here is a brief resume on doped oil in connection with Aircraft work. Four years ago some of Roberteon's doped oil was tried on the Merlin. As the Merlin was satisfactory on undoped oil the results achieved exacted no comment. When the Vulture was started up, however, on the first 2 hour run at rated altitude 13,000ft. the gear showed signs of distress. The attached photograph shows the "plucking" of the surface of the tooth which occurred. When the engine was run on D.T.D.109 to which had been added Robertson's dope in the proportion of 1% with agitation (this mixing can be done at the Factory) the trouble vanished. Since then all running and type tests (in all about 2,000 hours) have been done on this oil. Almost all the developments running has been done within 90% of the full torque. No disadvantages with regard to ring gumming have been observed from the dope or, in fact, any harmful results whatever. | ||