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 engineering changes and specifications for various components.
| Identifier | ExFiles\Box 18\6\ Scan042 | |
| Date | 8th December 1919 | |
| R.R. 199 (2pDT) (SD476 19-7-17) MP180865 - 3 - (BY/JH7/H.8.12.19) diameter between the two bores. Also the .875 diameter requires increasing to .925 to simplify forging. E.17259 - Annulus Casing Bush.-Material of this part requires altering from DPB to CPB. E.17274. Starting Handle Stop.-The Tool Dept. require "Heat-Treat" deleting. E.17286 - Planet Cage Cover. - Limits require adding. E.17280. Starter Worm. - 60° chamfer to be added to replace .025 radius in bore. E.17293. Motor Shaft Bearing Cover - thickness of material requires adding, namely, 18.SWG. Oil Pump. - E.15552. Taper Bolts. - Diameter of taper to be specified at large end instead of small end. Exhaust Pipes - The Section to be altered from 4230 to 4320, and the thickness of material to be added, namely, 20 SWG. etc. etc. BY/JH. | ||