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).
Search for suitable British-made spark plugs and the impact of plug dimensions on aircraft fuselage design.
| Identifier | ExFiles\Box 35\3\ scan 194 | |
| Date | 1st February 1928 | |
| To R.{Sir Henry Royce} from HS{Lord Ernest Hives - Chair}/TAG. c. to RG.{Mr Rowledge} BJ. c. to E.{Mr Elliott - Chief Engineer} BY.{R.W. Bailey - Chief Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} Wor.{Arthur Wormald - General Works Manager} +4196 HS{Lord Ernest Hives - Chair}/RAG1/LGS.2.28. SPARKING PLUGS ETC. +4196/+1918 We have still to find a suitable British made sparking plug to suit the 8/1 F.{Mr Friese} engine. Up to now only American Champion plugs have been used in engines in machines. Apart from finding reliable plugs for the engine there is another point which is often raised by machine builders (especially where the sparking plugs stick out from the sides of the cyls. as in the F.{Mr Friese} engine) and that is with the present trend of design of machines where the minimum head resistance is sought after, they try to cut down [REDACTED] the width of the fuselage as much as possible. I have had the point raised that if we had used such-and-such a plug the machine could have been so much narrower at the 'engine bay' and the performance of the machine would have been so much better. Whether this would be so or not there is great variation in the sizes and weights of sparking plugs, some samples which we have here for test could not for instance be used in the DH.{D. Henderson - Showroom}9a engine on account of fouling the fuselage longerons. We give below a few dimensions of various plugs with the weights. The length measurement is the distance the plug sticks out from the cyl. and does not include the threaded part. contd :- | ||