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).
Goshawk engine vibration issues causing camshaft wheel failure, attributing it to crankcase bending and proposing two stiffening solutions.
| Identifier | ExFiles\Box 74\3\ scan0262 | |
| Date | 21th February 1922 | |
| X4221 To CJ. from E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to Hs.{Lord Ernest Hives - Chair} E1/M21.2.22. GOSHAWK PRODUCTION. X.4219 X.4229 X4221 We know of no reason from a design point of view why the programme fixed for the above is likely to be interfered with except in connection with the vibration that occurs at high speed on the engine and causes failure of camshaft wheel. Mr. Royce has indicated that the most probable cause of this is the crankcase bending sideways, and Mr. Hives is at present engaged on experiments confirming this point. Calculation of stress in the crankcase appears very strongly to confirm that this is the trouble and that we shall require to alter the pattern so that more stiffness is obtained sideways. Two courses are open to us :- (1) To stiffen the top by side webs as on the 40/50, Eagle, Hawk, and Falcon. (2) To adopt the scheme originally intended for the Goshawk, in which the bottom half is fully webbed and securely bolted to the top half. This scheme is a modification of Condor and Goshawk 1. but has the important difference that the main bearing caps are separate from, and not solid with the bottom half. We are at present making drawings of both methods at W.W. Before leaving here on Saturday morning, Mr. Royce said he thought I ought to proceed to Derby if the position regarding this trouble had not cleared up within 3 or 4 days. E.{Mr Elliott - Chief Engineer} | ||