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).
Providing the drawing number for the 7° Sloping Bonnet.
| Identifier | ExFiles\Box 92\6\ scan0273 | |
| Date | 25th April 1936 | |
| x305 To D/BP. c. to By.{R.W. Bailey - Chief Engineer} c. to Mft. c. to EW/Skn. c. to Mft/Mr. Scott. Ha/Rm.{William Robotham - Chief Engineer}10/JH. 25.4.36. Replying to D/BP/Hull/JW.22.4.36, the drawing number of the 7° Sloping Bonnet is Lor.E.57313. Ha/Rm.{William Robotham - Chief Engineer} | ||