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).
Technical data sheet comparing specifications for Goshawk-II and 40/50 HP radiators.
| Identifier | ExFiles\Box 38\2\ Scan198 | |
| Date | 14th September 1923 | |
| X.3456 DETAILS OF GOSHAWK-II AND 40/50 HP. RADIATORS X.4240 X.3456 14.9.23. DETAILS. | Present G.11. Rad. E.51467 | Expl: G.11 Rad. E.52161 | 40/50 HP. Standard. | Marmon. --- | --- | --- | --- | --- Dimensions of matrix. | Height 19" Breadth 21.6" | Height 19.7" Breadth 20.825" | Height 20.25" Breadth 24" | Length of tube. | 3.95" | 3.5" | 4.8" | 3" Number of tubes. | 69 X 69 4761 | 71 X 67 4757 | | Diagonal. Overall area - matrix face. | 410.4 sq.in. 2647 sq.cms. | 410.25 sq.in. 2645 sq.cms. | 486 sq.in. | 449.5 sq.in. % free air passage of total face. | 70% | 70% | 70% | Volume. | 1620 cu.ins. .934 cu.ft. | 1435 cu.ins. .831 cu.ft. | 2332 cu.ins. 1.349 cu.ft. | 1348.5 cu.ins. .778 cu.ft. Wt.of air passing per hr. through the core at 95°F.{Mr Friese} | 900 f.p.m. 1800 " 3600 " | 7.800 15.600 31.200 | | 9.175 18.350 36.700 | Surface of core per inch of depth. | 26 sq.ft. | 26.2 sq.ft. | 30.75 sq.ft. | 32.9 sq.ft. | ||