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Were AA guns ever mounted on Aircraft for AA?

ANDY19422

Well-Known Member
Premium Member
As there were so many special projects during WWII, I was wondering if there had been any trials or plans drawn up to mount ground based Anti-Aircraft guns in to Aircraft for Anti-Aircraft use. I would think that something like a Flak 37 or QF 2 pounder MKVIII or even a 40 mm Bofors mounted in the Bomb bay of a Bomber that could be Traversed down would be a great weapon. The Aircraft could fly above and behind the Enemy Bombers out of their gun range at the same speed and the gunner could fly the plane via the gunsite like a bomb aimer. Fighters would be there for the Defence of these Aircraft and to finish off any damaged planes. I would think that one or two high Explosive hits to the fuel tanks in the wings would destroy an Aircraft, and a well trained team would only take five or six shots to Accomplish this. Four or five Aircraft would Decimate a stream of Enemy Bombers. 20 mm Flak guns could even have been mounted in cargo planes firing though the side door. Would these Ideas have been possible?
 
Andy
Not to sure about calibers bigger than 30mm being used on aircraft against others.
Try this.
http://en.wikipedia.org/wiki/Hawker_Hurricane_variants - I think this was intended more for ground targets. i would have tried though aircraft to aircraft!!!
I am also sure there was a version of the pounder that was used.
Fairly sure I posted here eons ago re a projectile I had that was a bit longer than the standard & I was informed it was for an aircraft mounted gun.
Obviously there is the 40mm bofors in the C130 Gunship - again this aircraft is for attacking ground targets.
Rgds
H
 
theoretically a good idea, practicably perhaps not. I suspect recoil could be a real issue for any ground mounted gun being used in aircraft of anything over 20mm.
Though having said that, I have no idea if experimens were undertaken.

regards Kev

here is a 6pdr gun used on a mosquito....
http://www.youtube.com/watch?v=M00f5RxhxLY

and 40mm wing mounted on Hurricane
http://www.youtube.com/watch?v=ix5xN8hlGLo

neither of these weapons were AA guns though
 
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The use of large calibre cannon on aircraft for shooting at other aircraft is fairly common and well covered by Tony Williams in Flying guns and on his website. Started in WW1 with 37mm cannon mounted in a SPAD fighter firing canister rounds. The Germans did a lot of work in WW2 as they faced the most 4 engined bombers, good example being the 50mm tank gun fitted in the ME-410 twin engined fighter that was used against USAAF daylight bombers until the single engined escort fighters arrived. Don't forget the 37mm cannon mounted as standard in the P-39 Airacobra widely used by the USAAF in the early part of WW2.
 
Thanks for the replys guys. I knew about the 40mm Hurricane cannon and the Mosquito 6 pounder, but as you say these were used on ground targets. I guess you wouldn't need the gun to fire Flak rounds as you would be able to accurately hit the Aircraft from short range. Something like the QF 2 Pounder MKVIII with a longer Air cooled Barrel would be my choice fitted in to a Mosquito. The round is smaller so more could be carried, the shorter range over the Bofors wouldn't be an issue. I think it's strange that no one had this idea on either side.
 
Thanks Vasco, I'll have to look it up. I think the idea of flying in formation above the enemy Bombers, Accurately sniping them would have been a better option than flying amongst them taking rushed shots and risking getting shot at by the massed guns of the bombers would have been a better tactic.
 
The use of large calibre cannon on aircraft for shooting at other aircraft is fairly common and well covered by Tony Williams in Flying guns and on his website. Started in WW1 with 37mm cannon mounted in a SPAD fighter firing canister rounds. The Germans did a lot of work in WW2 as they faced the most 4 engined bombers, good example being the 50mm tank gun fitted in the ME-410 twin engined fighter that was used against USAAF daylight bombers until the single engined escort fighters arrived. Don't forget the 37mm cannon mounted as standard in the P-39 Airacobra widely used by the USAAF in the early part of WW2.


The 50mm used by the Germans was an altered AT gun (Pak 38). As was the 75mm (Pak 40).
The only AA gun used in air was the 37mm Flak 18 as 3,7cm BK. The 20x138B MG C/30L was basically only a small scale trial whic was used on the He112 and saw service in the Spanish Civil War.
Normally AA guns are to heavy to be mounted in aircrafts.
All this was a reason for the Germans to work on rocket armament for aricrafts which came too late in the war and only the allies profited from these developments after 1945.
 
IIRC the Hungarians mounted a 40mm Bofors in some Me 210s, but I'm not offhand certain what they used them for. I have an even vaguer recollection that the Italians fitted the Breda 37mm AA gun to some planes, but I could be wrong there.

The US 37mm M9 cannon was a version of their M1 AA gun lightened for aircraft use and fitted with belt feed. It fired the usual 37 x 223SR AA ammo, much more powerful than the 37 x 145R used in the M4 and M10 guns in the P-39. It only saw experimental use, though (it was fitted to one P-63D and at least one twin-engined plane, plus some PT boats).

The Vickers Class S was actually designed for air-to-air fighting, firing the same ammo as the 2 pr pom-pom AA (although the gun was a different design and much lighter). The first installation was in a turret fitted to a much-modified Wellington bomber, intend for self-defence. Trouble was the muzzle blast blew the fabric off the fuselage.

The most ambitious scheme which came close to being tested was fitting a 3.7 inch AA gun, with autoloader, in a Mosquito, to fire prox-fused shells against bombers. There were also even wilder plans to mount the same gun in turrets fitted to super-giant bombers.
 
Thanks Tony for the info. I found two pics of the Wellington. If they had fitted the gun in the bomb bay instead with a limited traverse and Elevation I think it would have been a Bomber killer.
 

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If they had fitted the gun in the bomb bay instead with a limited traverse and Elevation I think it would have been a Bomber killer.

Always assuming that the Wimpey could have caught up with the bombers :rolleyes:

The obvious mount for the 40mm was the Beaufighter, which was actually tested with two of them in place of the quartet of 20mm cannon, but that was never taken any further.
 
Having had 30 years experience of air defence operations I fully support Tony's view. The intercept is everything in getting into a firing position. A head on pass will not work for a heavy fighter as only a single shot from a big gun is likely to be acheived. A stern intercept requires a speed advantage, either through performance or trading height for speed, even then most twin engined propellor driven WW2 aircraft suffer from a lower speed limit, known in the the trade as VNE (velocity never exceed). If you have a speed advantage of 60 knots over the formation then you can run them down at only 1 nautical mile per minute, so chasing the formation to get to firing range takes forever and at high power setting your fuel is going down even faster. The big gun is just dead weight and drag through this process and makes the situation worse. The second major issue is every heavy fighter could not live in an environment were the single engined fighter could reach. The history of air combat is full of the mass destruction of aircraft such as the Boulton Paul Defiant and Me-110 when engaged by true fighters. I would read the book written by Heinz Knoke, who flew Me-109 against the big daylight raids, he tried dropping bombs from above, firing 21cm rockets at the formations and was a master of the head on attack shooting directly into the cockpit. If he relaxed for a moment the escort fighters shot him down and this happened on a number of occasions until he was crippled.
 
Below is a photograph I came across in the book 'Guns in the Sky' by Chaz Bowyer. It shows a pair of 20mm cannon mounted in a mid upper turret on a Lancaster. As will be noted in the caption, it came too late in the war to see operational service, but was apparantly adopted for use by the successor the Avro Lincoln.
Within the text it says work was originally started as far back as 1940 but abandoned until later in the war.

regards Kev

P1280511.jpg
 
I think the idea similar to Andy's was to build Bell FM-1 Airacuda. It was a kind of "flying AA battery" rather than fighter. Two turrets with 37 mm guns were remotelly controlled by co-pilot/fire control officer. He has had a quite complex fire control system with gyro-stabilized sight, range finder and ballistic computer, similar to the systems used by AA artillery. The idea was to fly behind formation of enemy bombers and shot 'em from 1000-1500 m distance.
 
Thanks Speedy, I have never knew about that Aircraft. All these Aircraft seem to be from the Allied side. I'm amazed that when Germany was being bombed by hundreds of B17's before they got the Mustang escort Fighters that nobody thought of putting large guns on German Aircraft. I think the trouble was that Hitler was only interested in Offensive weapons and I guess this could be classed as Defensive.
 
Andy, the Germans certainly did put large guns on aircraft and were planning a lot more, but these were mostly designed for aircraft in the first place, not converted AA guns as you asked, which is why they haven't been mentioned up to now.

They introduced two 30mm aircraft guns, the low-velocity MK 108 (specifically designed for bomber-destroying) and the high-velocity MK 103 (also used for ground attack, as was the earlier MK 101) which saw extensive service.

They also fitted the high-velocity 50mm BK 5 (a version of the L/60 tank/anti-tank gun with an autoloader) to some Me 410 heavy fighters, and also developed the MK 214A using the same ammo (one of these was tested in the Me 262 jet).

At the end of the war they were testing two different 55mm guns: the MK 112 low-velocity and the MK 214B high-velocity guns, again for bomber-destroying (the 55mm HV round also being planned for an AA gun).
 
The data on that site seems to be taken straight from Chinn's great work, The Machine Gun. This is an invaluable source of information (especially on the nuts and bolts of how the guns worked), but it does contain errors and several of them are copied on the site.

On the specific question of aircraft gun armament, you might find these links of interest:

On WW2 fighter armament: http://www.quarry.nildram.co.uk/WW2guneffect.htm

On WW2 tank-buster guns and ammo: http://www.quarry.nildram.co.uk/tankbusters.htm

On the early development and use of aircraft cannon: http://www.quarry.nildram.co.uk/cannon_pioneers.htm

Plus several other articles on such subjects, if you scroll down the page to the Aircraft section: http://www.quarry.nildram.co.uk/miltech.htm

There's also this on Oerlikon cannon: http://www.quarry.nildram.co.uk/apib.html
 
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