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).
Dangerous Phantom III rear brake drum failure, attributing the cause to increased stress and recommending a new design with 4 ribs.
| Identifier | ExFiles\Box 92\4\ scan0104 | |
| Date | 7th November 1935 | |
| To E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} HS{Lord Ernest Hives - Chair}/AFM.{Anthony F. Martindale}21/KW.7.11.35. Phantom III Rear Brake Drums. We have received a report from G.W.H. (GWH{George W. Hancock - Head Chateauroux}/5/JAB) in which he says he has had a dangerous rear brake drum failure which he attributes to the water excluder scheme. The failure takes the form of crumbling of the drum edge. We do not think that the excluder itself is responsible because the front drums have the same scheme, but rather attribute the failure to the fact that while the front drums have been designed in accordance with our memo. Hs{Lord Ernest Hives - Chair}/AFM.{Anthony F. Martindale}25/KW.5.2.35, you have not applied our recommendations to the rear drums, in spite of the fact that you have increased the stress on the rear drums many times by reversing the positions of hand and foot brake shoes. We think the resulting flexing of the drum when the brakes are applied, which is very marked, has led to the breaking off of the thin drum edge forming the water excluder. We recommend that drums having 4 ribs 1" deep are immediately instructed for production, the ribs being in the positions they are now. This will also help us to overcome the trouble we are having due to fading on one of our cars. Hs{Lord Ernest Hives - Chair}/A.F.Martindale. | ||