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).
46-hour bump test of a Wraith Bumper Chassis rear end, detailing a stud failure.
| Identifier | ExFiles\Box 119\1\ scan0182 | |
| Date | 25th February 1939 | |
| 1024 To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/FWK. c. to Da.{Bernard Day - Chassis Design} c. to Rm{William Robotham - Chief Engineer}/PJH. Rm{William Robotham - Chief Engineer}/FWK.7/JH.25.2.39. WRAITH BUMPER CHASSIS. The rear end of the above chassis recently ran for 46 hrs. on the bump. Included in the specification were the .35% carbon steel axle tubes GW.1776/7. with 180 lb. of lead in the diff. casing. The only failure that occurred was the fracture of 3, 5/16 studs on the small diameter row of holes. These failed after 46 hrs. Rm{William Robotham - Chief Engineer}/FWK. | ||