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).
The standardisation and testing of a 4'/50 ignition coil for the Goshawk.
| Identifier | ExFiles\Box 49\5\ Scan002 | |
| Date | 10th November 1922 | |
| To R. {Sir Henry Royce} from EFC. {E. Fowler Clarke - Electrical Engineer} CJ. X4273 EFC {E. Fowler Clarke - Electrical Engineer} 3/T10.11.22. X.4273 4"/50 IGNITION COIL FOR GOSHAWK. We are sending you a standardisation sheet to sign for the 40/50 coil as a temporary measure. Our experiments, however, have now arrived at a point where we have made a coil (using mouldensite case) which does not fail under the most extreme conditions (including additional external spark gap) unless the coil case be touched with a big area of contact at the same time. Even then it is very difficult because of the temperature of the coil making it uncomfortably hot to touch. Such a coil we should pass for all road conditions and it is intended to have three more similar coils made up and proved out under these conditions. The temporary standardisation will enable us to proceed with the minimum interference to production as any superfluous coils that are made will of course be usable on the 40/50 chassis. EFC. {E. Fowler Clarke - Electrical Engineer} | ||