Performance comparison of the Goshawk II motor as applied to the Goshawk I engine with different reduction ratios.
| Identifier | ExFiles\Box 35\4\ scan 046 | |
| Date | 30th August 1921 | |
| X 4384. To R. {Sir Henry Royce} from EFC. {E. Fowler Clarke - Electrical Engineer} c. to CJ. c. to E. {Mr Elliott - Chief Engineer} c. to Da. {Bernard Day - Chassis Design} c. to Da {Bernard Day - Chassis Design} /T. } at W. Wittering. EFC {E. Fowler Clarke - Electrical Engineer} 1/T30.8.21. X.4384 - "GOSHAWK(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) II" MOTOR APPLIED TO "GOSHAWK(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) I" ENGINE. We attach table showing our estimate of the performance of the Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) II motor as applied to Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) I engine with a reduction ratio of 14.4 instead of 8.4 as on Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) II. It will be seen that the relative performances should be approximately in accordance with the following table :- Quantity. Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) II. Hoshawk(Aero Engine) I. Motor volts. 9.26 10.1 Amperes. 137 95.5 Electrical H.P. 1.87 1.29 Motor speed. 810 1363 Engine speed. 96.5 94.5 B.H.P. .85 .835 Efficiency. 50% 64.6% It will be remembered that the calculations of the performances are made for these for the Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) II engine in a quite cold condition, so that in nearly every case of starting the figures of operation here cited for Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) II are modified to more nearly those corresponding to Goshawk(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) I engine. MADE AT CROXLEY EFC. {E. Fowler Clarke - Electrical Engineer} | ||
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).