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).
High-speed vehicle test resulting in a catastrophic failure of an aluminum exhaust silencer due to extreme heat.
| Identifier | ExFiles\Box 11\3\ 03-page180 | |
| Date | 10th July 1930 | |
| To: Hs.{Lord Ernest Hives - Chair} From G.W.H. x79419 Hôtel de France, Châteauroux, Indre. 10/7/30. We carried out yesterday some continuous high speed tests for water temperature, which we have reported to you. The car had been fitted up with an exhaust pipe leading direct from the manifold to the rear silencer. A higher speed with this was obtained, the tests were carried out at a maximum speed of 80 M.P.H. The continuous high speed made the aluminium portion of the rear silencer so hot that it actually started to melt, and we had just completed the tests and returned to Châteauroux when the aluminium portion of the silencer collapsed, a large hole being blown through on the top side. The exhaust flame through the hole very nearly set the car on fire, therefore we had to return at a very moderate speed. The whole of the aluminium portion has cracked the whole way round along the bosses, and is an entire failure. We have definitely come to the conclusion that aluminium is not suitable in hot weather combined with the exhaust heat for the exhaust system. We are now in a hopeless position with the exhaust, and as stated in our telegram to you we are proceeding to Paris to fix up an whole steel exhaust system. Other features of the car which were noticed during these tests were: The steering becomes very heavy at slow speeds, one can actually feel the springs in the side tube having to be wound up choc-a-bloc to effect a movement of the wheels. This is evidently a failure of the lubricating qualities of the oil on the ball ends. I decided to go back to amber gear oil for the central lubrication, | ||