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).
Letter to Wellworthy Ltd. discussing raised crown pistons, ignition governors, and big end bearing experiments for various engines.
| Identifier | ExFiles\Box 148\1\ scan0196 | |
| Date | 22th September 1939 | |
| 1256 Rm.{William Robotham - Chief Engineer}2/MH.{M. Huckerby} 22nd. September, 1939. J.Howlett, Esq., Messrs. Wellworthy Ltd., Lymington, HANTS. Dear Howlett, I went up to Leyland last night to see them about the raised crown pistons. The position with regard to them is that they do not seem to have reproduced our results, also the ignition advance is rather critical. They say that their ignition governors are not sufficiently durable to give constant ignition advance curves over long periods, and in consequence, this would be a serious defect. I gave them the figures that we obtained on our engines, and perhaps they will be communicating with you again if they want to do anything further in the matter. They had an isolated case of trouble with their big end bearings in AC.9; I think that this may have been due to insufficient nip. I am putting them "au fait" with our current practice. They are designing a new unit with a big end rather like our Phantom III, and here again I was able to give them particulars of how we had done the job. On the whole they seem very satisfied with the bearing. It has now been agreed that we shall carry on with big end experiments on the Merlin, and if the results justify it, going ahead on the Griffon. I think that part of the resistance of the Aero Division to using AC.9 is due to the fact that they tried it on main bearings previously; the result was not entirely successful. Yours sincerely, | ||