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).
Laboratory report on the examination of failed valve springs from a 15,000 miles test.
| Identifier | ExFiles\Box 97\4\ scan0288 | |
| Date | 10th January 1939 | |
| Handwritten: Comment P - herewith report on failed springs 8BV. Looks as though backing up to max speed overstressed them. Rm{William Robotham - Chief Engineer}/Swdl{Len H. Swindell} Handwritten: M.1775. 450b. Typed: To Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} from H1/EJW. Laboratory. H1/EJW. 1/JM.{Mr Morley} 10.1.39. Valve Springs (15,000 miles test). Your ref. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} 4/MH.{M. Huckerby} 2.1.39. We have been unable to find any reason for these failures. Hardness tests, bend and fracture, etching tests and micro examination of the failed springs gave satisfactory results. Springs returned herewith. H1/EJW [Signature] | ||