20 MM Cannon in Spitfires

[Elwyn]

On some Spitfires with 20MM cannons there is a protrusion from the leading edge of the wing next to the gun barrel. i had always assumed it must be some part of the gun mechanism but on looking at see through drawing the other day I noticed the leading edge protrusion had nothing behind it, so what purpose did it serve?

[4RG.I.'S]

If you mean when there is only 1 cannon per wing, it may be the cover for the other cannon. See universal or C wing in the link:

http://ram-home.com/ram-old/spitfire-5.html

[PeterA]

If it is outboard of the 20mm Cannon on a Mk Vc than it is the optional station for the second Cannon.

If it is outboard of the 20mm Cannon on a Mk IX it, is spare and aerodynamically covered as there was close similarity to the Mk V wing but no two Cannon option per wing.

If it is inboard of the Cannon on the Mk IXe then it is the station for the .5 Browning.

PeterA

ps. Despite what you will publicly read, there never was a Mk IXb or a MK IXc.

In official documents...just Mk IX and when the Mk IXe was introduced the former became 'Early Mk IX' in the manuals APs etc.

[Elwyn]

Thanks much.