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).
Visit to Boscombe Down to assess the installation of proposed 15mm guns in place of .303 guns on Spitfire and Hurricane aircraft.
| Identifier | ExFiles\Box 175\3\ img111 | |
| Date | 18th January 1940 | |
| SECRET. COPY TO Hm.{Capt. W. Hallam - Head Repairs} To Hs.{Lord Ernest Hives - Chair} from Ve/NF. Ve/NF.2/CB.18.1.40. INSTALLATION OF PROPOSED 15 mm. GUN IN PLACE OF EXISTING .303 GUNS IN SPITFIRES, HURRICANES, ETC. Report of Visit to Boscombe Down. Present :- Ve, Rm{William Robotham - Chief Engineer}, Lp{Mr Lappin}, Ve/NF. Representatives met :- Group Captain MacEntaggart (C.O.) Squadron Leader Banks. Flight Lieutenant Degne. Flight Lieutenant Whitworth. Mr. Rowarth (Chief Engineer) The visit was made to form an opinion of the difficulties likely to be encountered in installing the proposed 15 mm. gun in place of the existing .303 Browning, without alteration to the structure of the planes or turrets. The general conclusion reached was that, although the space available was confined, particularly in the case of turrets, the difficulties of designing a 15 mm. gun to suit these conditions are not insuperable. The design will be determined more by the position of the existing ammunition and ejector chutes, etc. than by space conditions. It was generally agreed that the gun should be suitable for both fixed and turret installations. It should be preferably recoil operated (as against gas operated), and should be fed by disintegrating belt; the feed should be readily interchangeable from left to right hand. The ejection should be downwards. Ease of maintenance is important. The consensus of opinion was that there was nothing against our proposal to use a short barrel, although this could only be determined finally by ballistic requirements, at present unknown. On the other hand, if a long barrel is required, there should not be any great difficulty in accommodating it. continued. | ||