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 from the Royal Aircraft Establishment discussing crankshaft stiffness and eight-cylinder engine design.
| Identifier | ExFiles\Box 63\4\ scan0094 | |
| Date | 30th October 1929 | |
| G.16/859. X.4499. When Telephoning with regard to this letter please ask for Extension Number......20........ TELEGRAMS : Ballooning, South Farnborough. TELEPHONE : 108 North Camp, 361 Aldershot, & 108 Farnborough. All Stores to be addressed :— R.A.E. Siding, Farnborough Station, Southern Railway (L. & S.W. Section) All communications to be addressed to The Chief Superintendent, OUR REFERENCE: E.4/1179C/19. YOUR REFERENCE: ROYAL AIRCRAFT ESTABLISHMENT, SOUTH FARNBOROUGH, HANTS. 30th. October, 1929. S.S.Tresilian Esq., Messrs. Rolls-Royce Ltd., DERBY. Dear Mr.Tresilian, Crankshafts Many thanks for your letter of the 19th. instant with its further information re crankshaft stiffness. My first attempt to improve upon the formula, using the data you supplied recently, did not lead anywhere. I may have more success later. It is difficult to generalise about engine types. The eight cylinder aircraft engine got a bad name through T.V. trouble with the geared Arab and with the Hispano. This is not to say that an eight cylinder engine designed with due regard to T.V. should not be satisfactory. The idea that having many cylinders ensures good conditions for the reduction gear needs qualification, as you know, for bad torsional criticals must be avoided. The balance of the eight cylinder Vee engine is not good - unless the 90° shaft with balance masses is adopted. With the 90° shaft the balance masses would assist in lowering the natural frequencies of single node vibration. I know/ | ||