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 discussing the results of a bumper rig test on a car.
| Identifier | ExFiles\Box 170\2\ img089 | |
| Date | 21th July 1931 | |
| Hy{Tom Haldenby - Plant Engineer} W. A.{Mr Adams} Robotham Rolls Royce Ltd Derby England 6 copies. Hey Dear Rul A belated reply to yours of July 21/31 @ Bumper Rig We have only just got a car on it and 15 hours at 11 mph (with 2" bumps, 2 per drum, staggered) does not show up very much. This was an old car however with frame, coachwork etc very loose (also a flexible frame) We are putting a new frame & body shell on this same car and bolting up the body tight so as to reproduce the stiffness of our latest jobs and also increasing to 3" bumps. 11 mph I don't know what combination of bump height & speed may be expected to give the most destructive results. 11 mph seems to work the front axle relative to frame more than our next step in speed, 14 mph, but probably the latter speed will find out more about the frame & coachwork. | ||