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).
Road tests for sling lengths and their effect on buffer clearance and axle movement.
| Identifier | ExFiles\Box 16\7\ Scan330 | |
| Date | 17th November 1930 | |
| -2- Hs{Lord Ernest Hives - Chair}/AJL.1/MJ.17.11.30.Contd. 13. 8". Several different lengths of sling were tried, tests being made over rough roads, main roads, and humped back bridges. The minimum reasonable buffer clearance on rebound appears to be 9" (this does not allow for compression of the cushioning rubber under the axle which would probably be about 1/2"). Under this condition the restraint due to the sling only comes into operation when driving over humped back bridges; the rear wheels leave the ground earlier than when the axle is not restrained, but this is not noticeable to the car occupants. Two bumps are felt, one on rebound which is not violent, and one on max. bump which of course is felt normally. There is no additional discomfort to the occupants. We think 9" is the limit to which the axle movement can be safely restricted. This represents a reduction of nearly 35%. Hs{Lord Ernest Hives - Chair}/AJL. | ||