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).
The failure of two taper valve springs during rig testing, noting potential flaws.
| Identifier | ExFiles\Box 80\3\ scan0225 | |
| Date | 8th November 1912 | |
| Mr Royce 8-11-12 TBB4/L81112. Re Taper Valve Springs. No.2 inlet taper valve spring broke after 3600 miles on the valve spring testing rig. Another taper inlet valve spring has also broken after 9600 miles on the rig. Both of these fractures have slight indications of a flaw. | ||