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).
Cross-section diagram and explanation of an umbrella rotor designed for pure air circulation.
| Identifier | ExFiles\Box 61b\4\ scan0112 | |
| Date | 14th May 1927 guessed | |
| -3- Contd. This umbrella rotor looks more like a scheme than an accident made with the object of keeping up a circulation of pure air around the make and break, any gas formed at the H.T. points being carried away without mixing into the air below. E.{Mr Elliott - Chief Engineer} | ||