Graph comparing the speed and power consumption of various engine fan designs.
| Identifier | ExFiles\Box 75\3\ scan0030 | |
| Date | 19th December 1924 | |
| Y-Axis Left: FAN SPEED (R.P.M.) Y-Axis Right: MOTOR OR ENGINE POWER REQUIRED TO DRIVE FAN (H.P.) X-Axis Top: 40/50 ENGINE SPEED (R.P.M.) X-Axis Bottom: CHASSIS M.P.H. 15/52 AXLE. 33.5" TYRE DIA. Chart Labels: SPEED, POWER Key: Fan lip dia. 1. Standard 40/50 six-bladed fan. 22" 2. Standard 40/50 six-bladed fan with three blades removed. 22" 3. EAC. four-bladed fan. 23" 4. Hispano fan. 17 1/2" 5. High speed 40/50 six-bladed fan. 22" 7. Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) fan. 18" 8. Fan made to recommendations of Prof. Watts. 22" 9. 2nd Fan made to recommendations of Prof. Watts, but with swept back blades. 22" 10. Expl. EAC. fan - first modification. 23" 11. Ditto, second modification. 23" 12. Ditto, third modification. 23" Annotations: G H.E.W. G7S. | ||
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).