Spitfire Mk I-II and Hurricane Mk I wing machine gun configuration

[paradoxguy]

Why were the 8 wing machine guns in the Spitfire Mk I and II spread out in a 1-2-1 configuration when the Hurricane's 8 wing guns grouped together in each wing? Were there advantages to the Spitfire's wing gun arrangement, or was the gun configuration necessary for the thin elliptical wings of the Spitfire?

Thanks for reading and any information.

Ken

 

[Shortround6]

Because of the thin wings on the Spitfire. The didn't want to route the ammo belts over the tops of the guns like was done on the Hurricane so the ammo boxes for guns 1 and 2 are between guns 1 and 2 and the ammo boxes for guns 3 and 4 are between guns 3 and 4.

 

[Aozora]

One major problem with the Spitfire's configuration was that the outer wings could flex slightly under load, or when the weapons were firing, meaning that the firing pattern of the outer .303s was cone shaped. There doesn't seem to be any clear information about how bad the dispersal was, but in later Spitfire marks (IXE etc) the outer weapons were jettisoned in favour of 2 .50 cal Brownings mounted closer in to the 20mm Hispanos.

 

[Greyman]

All firing patterns are cone shaped, no matter how rigidly mounted.

As you said, no clear information on how much worse the outer mountings were dispersion-wise, but from my understanding the problem was the alignment of the weapons once the wings were flexing in flight.

 

[nuuumannn]

The aeroelasticity of the Spitfire's wings in tight manoeuvring was a problem with the first Mk.Is fitted with cannon only in their wings; the wing skins came into contact with the Hisso's magazine, which jammed the gun. 19 Sqn's cannon only Mk.Is were not popular. The Mk.Ib with the cannon and .303s was not much better.

 

[OldSkeptic]

True nuuumann, that's why they strengthened the wing for the Mk V (and increased the ultimate aileron reversal speed too), mostly by thicker skinning. A bit more weight but made it a better gun platform and with a better roll rate (it wasn't all just the metal covered ailerons).

The Mk V was Alec Henshaw's favourite version for his incredible aerobatic demonstrations (even Quill was in awe at what he could do with a Spit).

 

[stona]

The answer to the original question was given correctly in the first response.
The other factors mentioned have nothing to do with the reason for the positioning of the machine guns in the 8 gun Spitfire.
Cheers
Steve

 

[paradoxguy]

Thanks for the responses, especially shortround6 and stona. Shortround6's explanation seems perfectly logical as the reason for the Spitfire's 8-gun configuration.

 

[stona]

The aerolasticity issues were an initial problem for other armament, particularly the early cannon installations as nuuumann correctly said. It wasn't the only problem with the installation, but this isn't the topic here. Suffice to say that the shell ejection system was also contributing to the jams. The main spar was modified and if some skins were altered (I can't find a record of this) it would seem entirely reasonable. As I've said many times in many threads, "just" doing something to any WW2 aircraft is invariably a lot more difficult to do than to write!

When the heavier armament was adopted, whilst the aerolasticity of the wing may have been a consideration it wasn't the major factor in determining the position of the cannon/MGs.

Cheers

Steve

 

[Shortround6]

This site has some diagrams/drawings;

http://spitfiresite.com/2010/04/concise-guide-to-spitfire-wing-types.html