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).
Blueprint of an aircraft showing wing armament layout and gun specifications.
| Identifier | ExFiles\Box 176\1\ img035 | |
| Date | 17th July 1940 guessed | |
| 8 - 9.5% GUNS 250 ROUNDS OF AMMUNITION PER GUN. RATE OF FIRE 970 ROUNDS PER MINUTE PER GUN MUZZLE VELOCITY 2580 FT/SEC. | ||