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).
Letter to the Lodge Sparking Plug Co. Ltd. regarding the testing of KRG plugs, noting pre-ignition failures, and requesting 50 KR4A plugs for an Atlantic flight engine.
| Identifier | ExFiles\Box 79\1\ scan0154 | |
| Date | 11th January 1919 | |
| X.607 X.3470 LH{Mr Haworth}1/LC11119. 11th. Jan. 1919. Messrs. The Lodge Sparking Plug Co. Ltd., R U G B Y. Dear Sir, With reference to the KRG plugs, the first 2 dozen which you sent were tested by our Mr. Platford on production engines. Compared with the KR3, they were an improvement. Several of them failed, however, after 8 to 10 hours running due to pre-ignition. We are testing some more of these plugs under the conditions that the engine will work on an Atlantic flight. In the meantime, we should like you to go on making up 50 KR4A plugs, an order for these is being sent on to you. We think that there is a bigger margin of safety on the KR4A than there is on the KRG. Will you make certain that with the KR4A, that all the terminals are properly locked and pinned. We have had one KR4A break off at the top where we have had to drill the copper centre to peg on to it the brass end. We shall leave it to you to see that the plugs are quite sound mechanically. X.3486 With reference to the F.7. spirit, we are very keen on being able to test some of this and if we find it satisfactory, should certainly recommend it for any long flights. Yours faithfully, | ||