Test data on the power required to drive a Goshawk No. 2 radiator fan with modified blades.
| Identifier | ExFiles\Box 75\3\ scan0218 | |
| Date | 5th January 1925 | |
| POWER REQUIRED TO DRIVE RADIATOR FAN IN VARIOUS CIRCUMSTANCES. No. 22 Circumstances :- Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) fan (No 2) with width of blade reduced by 1 inch, thus giving blade small positive angle. | Date | Motor field current (amps.) | Motor speed. | Fan Speed. R. {Sir Henry Royce} | Ratio. | Volts across motor brushes. | Motor armature current. | Volts across motor brushes light. | Motor armature current light. | Thrust (lbs). | |---|---|---|---|---|---|---|---|---|---| | 5-1-25 | 1.493 | 440 | 1000 | 2.27 | 63.73 | 5.60 | 62.10 | 1.92 | 1.438 | | 5-1-25 | 1.492 | 617 | 1400 | 2.27 | 88.69 | 6.65 | 86.03 | 2.03 | 2.875 | | 5-1-25 | 1.492 | 793 | 1800 | 2.27 | 113.55 | 8.00 | 110.48 | 1.97 | 4.625 | | 5-1-25 | 1.492 | 973 | 2200 | 2.26 | 138.41 | 9.65 | 135.24 | 2.05 | 6.750 | | 5-1-25 | 1.492 | 1155 | 2600 | 2.25 | 164.50 | 11.45 | 158.37 | 2.09 | 9.125 | | ||
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).