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).
List of Goshawk size fans tested, detailing modifications and tip diameters.
| Identifier | ExFiles\Box 75\3\ scan0053 | |
| Date | 24th February 1925 | |
| X1017 24.2.25. X.1017. LIST OF GOSHAWK SIZE FANS. Nos. & Descriptions of fans tested. Fan tip dia. 4. Hispano fan. 17½" 7. Goshawk. 18" 21. Wide bladed fan. 18" 22. No. 21 with 1" cut off leading edges. 18" 23. No. 22 with leading edges rounded off. 18" 24. Fan similar proportioned to the EAC. expl. fan, but with curvature the same as that of the Hispano. 18" 25. New fan made up similarly to No. 21. 18" 26. & 26a. No. 25 with 1½" cut off the leading edges and angle of attack increased. (Best result and chosen for standard). 18" 27. New fan made up similar to No. 26. 18" | ||