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).
Schematic diagrams of a gearbox layout, gear engagement, and ratios.
| Identifier | ExFiles\Box 104\4\ scan0106 | |
| Date | 9th March 1932 guessed | |
| FIG II ENGINE PROP SHAFT 1ST 2ND 3RD CM No GEARS TURNING WITH ENGINE IDLING FIG I ENGINE PROP SHAFT 41 19 A 27 33 B 35 25 C X Y TOP BC 1:1 X TO RIGHT Y TO LEFT 3RD 1.3:1 " RIGHT 2ND AB 2.0:1 LEFT LEFT 1ST AC 3.0:1 " RIGHT ALL SILENT GEARS WITH 3 CONSTANT MESH PINIONS | ||