Graph comparing the thrust and power of different engine fans against fan speed.
| Identifier | ExFiles\Box 75\3\ scan0215 | |
| Date | 9th February 1925 | |
| II. No. FAN. 4. HISPANO-SUIZA 7. PRESENT STANDARD GOSHAWK(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)). 27. FINAL EXPERIMENTAL GOSHAWK(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)). POWER REQUIRED TO DRIVE FAN. (H.P.) 0, .5, 1.0, 1.5, 2.0, 2.5, 3.0 AXIAL THRUST OF FAN IN LBS WEIGHT. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 THRUST POWER FAN SPEED. (r.p.m.) 0, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400, 2600 H.E.W. 9-2-25 E & C. 9/2/25 | ||
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).