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).
Variable pitch rubber blade cooling fan, its performance benefits, and potential cost savings.
| Identifier | ExFiles\Box 173\1\ img304 | |
| Date | 31th January 1934 guessed | |
| X tube the more material that can be got in for a given rate & the less the stress This stuff also used in Clutch centres Cooling Fans The variable pitch rubber blade root fan was standardised on the 16 Cyl this year but turned down on account of cost (5£ per car). This fan delivers the same quantity of air as the std one up to 4000 R.P.M. At 2000 R.P.M. 25% less At 3400 R.P.M. it requires 4.5 H.P. to drive it against 16 H.P. for the std. which as you can imagine is a stalwart specimen. It occurs to me this is too good to miss as it might enable us to save a pound or two on the rad and give almost complete silence, at the same time be enormously efficient for hill climbing. It will also be at least worthy of trial on the Tank though I fancy it may cannot give much draught away even at high engine speeds. I am bringing a sample back and find out patent situation | ||