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).
Failure analysis report on connecting rod bolts from a Kestrel V engine due to faulty material and corrosion.
Identifier | ExFiles\Box 10\5\ 05-page074 | |
Date | 13th May 1937 | |
F.T.B. No. 22. REPORT ON CONNECTING ROD BOLTS FAILED IN SERVICE ON KESTREL V ENGINE NO. 15309. S/LDR. MAITLAND'S AIRCRAFT, 210 SQUADRON. EXAMINATION. The two failed bolts were examined for material and heat treatment. They were found to be made from a faulty batch of material to Specn. D.T.D. 136 which has now been withdrawn. The fracture in each case started from a corrosion pit on the unthreaded portion of the bolt. CONCLUSION. The primary cause of failure was the use of a faulty batch of material. The secondary cause of failure was the formation of corrosion pits which acted as stress raisers. RECOMMENDATION. It is recommended that all bolts made from this batch of material should be withdrawn from service. A list of engine numbers concerned is attached. It is also recommended that all Kestrel connecting rod bolts should be cadmium plated all over to prevent the formation of corrosion pits. F.T.B. | ||