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).
Instructions for the installation of Rolls-Royce 40mm cannon guns, detailing fuselage modifications and replacement of existing guns.
| Identifier | ExFiles\Box 176\1\ img199 | |
| Date | 27th May 1941 guessed | |
| -8- Installation of Rolls-Royce Cannon Gun. With regard to the installation of the guns, and the fact that the main planes with their gun mountings will be supplied complete for the completion of the performance calculations, and also to ensure that aircraft is fitted with the latest type of installation, it has been arranged that we should proceed with the installation of 2 Rolls-Royce 40 m.m. guns to replace the existing 4 20 m.m. guns. The Rolls-Royce guns will be mounted in approximately the same position in the fuselage, and the following is the general position as regards modifications involved. Certain modifications to the fuselage will be necessary in order to provide a rectangular hole in the keel members for discharge of the spent cartridges into the body of the fuselage. These modifications consist of stiffening up the keel members and will be covered by an Instruction Sheet on Bristol drawings. It should be particularly noted that the modifications shown on these drawings for the ejection orifices on the port keel member should also be applied to the starboard keel member, as on R.2061 we are going to install a gun on each side. The alteration to the starboard keel member, shown on the Bristol drawings, is produced only to cover the case where the gun is being installed on the port side only and this reference on the Bristol drawings therefore does not apply to our own installation. A further modification which will be involved in this conversion is the replacement of the two front panels containing the four blast tubes with two new front panels which will only contain two blast tubes. Will W.H. please contact Bristol's with reference to the supply of two new front panels. P.T.O. | ||