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).
Analysis of collision test results on a Phantom III chassis, detailing rocking shaft damage and steering effects.
| Identifier | ExFiles\Box 153\1\ scan0304 | |
| Date | 16th May 1939 | |
| -4- Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}3/MH.{M. Huckerby}16.5.39. (b) The impact required to twist the rocking shaft is very severe indeed and would, we believe, certainly result in extensive damage to any chassis other than a Ph.III. That it is possible to twist the rocking shaft and indent the bearing tracks without doing any other damage to the chassis is proved by Test 14. We are convinced, however, that an orthodox axle would have badly bent by this impact. A rocking shaft which has already been twisted a large amount as in Test 14 is still quite strong as efforts to increase the twist in Tests 15 and 16 were unsuccessful. During none of the collision tests was any noticeable reaction felt on the steering wheel. We consider that the only fault of the Ph.III so far as accidental impacts are concerned, is that it is possible to twist a rocking shaft right off. This can very easily be cured by making the smallest diameter of the shaft much longer so that the lock stops on the front suspension are hit before the shaft is seriously weakened. A twisted shaft would then make itself apparent by greatly reduced steering lock in one direction. We are continuing the collision tests on the old Ph,III bumper chassis. It will be appreciated that owing to the extensive damage inflicted on both the chassis and the earth bank etc. these tests are extremely laborious. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||