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).
Bump test conducted on a Goshawk-11 chassis, detailing component failures over time.
| Identifier | ExFiles\Box 119\2\ scan0173 | |
| Date | 1st September 1922 | |
| X4268 To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to C.J. c. to R.{Sir Henry Royce} c. to Da.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} Hel/LGS.9.22. BUMP TEST ON GOSHAWK-11. X4268 We have run the front of a chassis fitted with all parts similar to what is being used on the standard production chassis. This means we have the latest steering levers, and increased size of ball joints. The chassis was also fitted with the latest shock absorbers. The failures during this run were as follows:- Goshawk 11. standard production chassis - front end - 2" bumps - 110 r.p.h. - bumps 180°. Front springs (Firths) - top leaves broken after 8, 15½, 16½, 23½, 17½, 18½. 9½, 7. Woodheads - 4½, 7½, 12, 16½, 6. 11 spring clips broken in 93½ hours running. 2 front shock absorbers castings forming base broken 42 and 66 hours. Dumb iron broken after 93½ hours running. We consider the result of this test very satisfactory indeed as no major part of the chassis has failed until 93 hours had been run. The result is equally as good as we get on the 40/50 chassis running with the same speed and the same cams. When running on the bump test the steering wheel is bolted firmly so that it cannot move. One would anticipate much greater shocks on the steering under this condition than when running on the road. The side steering tube during this test was fitted with the original type set-up springs with limited movement. | ||