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).
List of specifications and modifications for various parts identified by reference codes.
| Identifier | ExFiles\Box 114\1\ scan0277 | |
| Date | 12th February 1940 guessed | |
| - 2 - 1.R.1. - contd. Spring Seats Welded on. Strengthened centre case bolts. 2.R.II as 1.R.1. 31.G.VII. as 4.B.50, but normal thickness tubes. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||