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).
Blueprint graph displaying a series of numbered performance curves.
| Identifier | ExFiles\Box 179b\3\ img362 | |
| Date | 6th April 1933 guessed | |
| 3500, 3250, 3500, 3250, 3000, 2750, 2600, 2500, 2750, 2600 | ||