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).
Close-up photograph of the starter ring gear teeth after endurance testing.
| Identifier | ExFiles\Box 165\7\ img015 | |
| Date | 19th June 1951 guessed | |
| RM{William Robotham - Chief Engineer} 576 - RR DRIVE - 25000 STARTS (B80 No.1) | ||