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).
Sparking plug trouble on an 'Osprey' aircraft, leading to engine cutting out.
| Identifier | ExFiles\Box 58\2\ Scan283 | |
| Date | 23th January 1936 | |
| V6 000 H/P. C.P. Hs{Lord Ernest Hives - Chair}/Wst re "OSPREY" AIRCRAFT - SPARKING PLUG TROUBLE With reference to your Lp.{Mr Lappin}12/LAM.21.1.36, the complaint appears to have emanated in regard to an "Osprey" aircraft which was reported as having forced landed at Mount Batten owing to the engine cutting out. By special request we arranged for our tester Hunt at Gosport to proceed there to attend to the trouble. In the meantime they appear to have ascertained that by fixing a new set of sparking plugs the trouble disappeared. On the arrival of our man there he was able to run the engine with the old and new sparking plugs and confirmed that cutting out did take place with the old plugs fitted. The matter was one of concern, however, as these plugs had only run two hours since cleaning, according to the records, the engine itself only having done 20 hours' running in all. The ignition plugs fitted were the K.L.G.V9/1B, the engine being a Kestrel V, and 6 lbs. boost being used. The case was reported to Hs{Lord Ernest Hives - Chair}/Wst. We are rather anxious to obtain for Hs{Lord Ernest Hives - Chair}/Wst's inspection a sample of the faulty plugs referred to, as these appear to have been all delivered to the Air Ministry and our man has now returned to Gosport. Our man reported the fact that a thorough examination and test of the faulty plugs showed they appeared to suffer from lead deposit on the centre electrode. He also reported the fact that this engine had been doing a considerable amount of idle running. It is certainly a fact that we have experienced this trouble with this type of plug, and have for some time obtained the sympathy of Hs{Lord Ernest Hives - Chair}/Wst that the K.L.G.V9/1B, although the only approved plug suitable for 6 lbs.take-off boost, does appear to suffer very badly, (being too cool) when considerable idling is being done and the engine run under light load conditions, 230 fuel being used,(fully rated engines) | ||