Why did US fighters not use cannon in WW2?
IIRC they were originally MKll A Series 2 , when they first were introduced? They became the IIB shortly after.
For clarity could someone define the difference between 'Cannon' and 'Machine Gun' please?
Thanks.
Thanks.
There isn't a universally accepted definition but we (RAF that is) tend to regard anything above 14.7mm as a cannon but other factors are considered too. Cannon projectiles are typically large enough to accept an HE charge (amongst other options) and usually fired via an electric impulse (rather than striker fired) and typically employ either a rotating breach or barrel (rather than a simple reciprocating mechanism).
For aircraft the 'cannon' term is an abridged form of auto cannon or rotary cannon, but most aircrew just call it a gun.
For aircraft the 'cannon' term is an abridged form of auto cannon or rotary cannon, but most aircrew just call it a gun.
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I asked a wartime Spit pilot why you never saw the Mk IX in four cannon fit. They had the fitting for four cannon but only carried two. Apparently the wing flexed so much when firing four cannon that aiming became pretty much useless.
As has been noted, the early F4 carried only four 50 cal guns. There was some opposition from pilots when they released the six gun wing as the ammunition carried for each gun was less, and as the pilots figured, if you can't hit a target with four guns you're not going to hit it with six.
As has been noted, the early F4 carried only four 50 cal guns. There was some opposition from pilots when they released the six gun wing as the ammunition carried for each gun was less, and as the pilots figured, if you can't hit a target with four guns you're not going to hit it with six.
I recently read "MIG Menace Over Korea" by Nicolai Sutiagin (22 kills) and he was quite derogatory about the F-86's armament. He said they often found strikes on their Migs where the .5 bullets had bounced off.
The F-86 armament of 6 x .50 cal MG was not effective. The US Navy instead incorporated 4 x 20 mm cannon into it FJ-2 Fury II proving the airframe could accommodate them. Unfortunately they were too late to take part in the Korean War and thus prove the superiority of the 20 mm cannon against the .50 cal mg.
Several US fighters imported into Europe early on showed substantial performance loss due tot eh need to fit armour, armoured glass and self sealing tanks....... the original P-51 being a case in point.........
Early versions of the P-51 had four 20mm cannon, a report written on 30 December 1942 recommended changing from the 20mm to .5 inch because,
The present armament is considered adequate, but is functionally unsatisfactory. It is believed that four .50 cal (high rate fire) guns would furnish ideal firepower.
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Indeed - tho to be pedantic the British ones were NA-73's and NA-83's and because we'd spec'd them they came with most of the necessary kit -and adding the "Merlin" later made it the best fighter of WW2
Somewhat off topic but reading around I never realised that the P-47 bubble canopy was adopted after they tested it with a Typhoon canopy.. I think the P-51 canopy was a US improvement over the UK part bubble canopy adopted from the Spitfire
Somewhat off topic but reading around I never realised that the P-47 bubble canopy was adopted after they tested it with a Typhoon canopy.. I think the P-51 canopy was a US improvement over the UK part bubble canopy adopted from the Spitfire
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What tends to be forgotten is that the P-51 started life as a British aircraft, albeit designed and produced in the USA. It was built to specifications laid down by the British. No modification was necessary upon arrival in the UK. The P-51 came with all the items you list Harry. Windscreen was 1.5 inch armour glass,the pilots seat had a 5/16 inch plate from just below the seat to a point level with his shoulders and a 7/16 inch plate above this to protect the head, a 3/8 inch thick firewall, armour plate forward of the coolant tank, and self sealing fuel tanks. You can see the British bought their combat experience to the design.
Early versions of the P-51 had four 20mm cannon, a report written on 30 December 1942 recommended changing from the 20mm to .5 inch because,It doesn't spell it out, but infers to me that stoppages were a problem.
Early versions of the P-51 had four 20mm cannon, a report written on 30 December 1942 recommended changing from the 20mm to .5 inch because,It doesn't spell it out, but infers to me that stoppages were a problem.
WW2 German aircraft weapon designations seem to have a clear demarcation of machine gun -up to 20mm and, machine kannone for 30mm weapons. Cheers
OAP
OAP
I recall reading that Capt Eric "Winkle" Brown shot down 2 FW 200 Condor whilst flying the Grumman Martlett (Wildcat) from HMS Audacity. Thus the .50 cal ammunition was effective against a large 4 engined aircraft. Although the Sea Hurricane with only 8 .303cal mg did manage to down 3 FW 200 Condors, there were a number of occasions when they were unable to inflict sufficient damage to shoot them down.
the Move to 20mm Hispano and ultimately 4x of such...
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I'm going to step out on a limb here and probably get flamed, but when you say "stoppage" I infer that to mean that the weapon was prone to jamming, and that the term has nothing to do with its actual effectiveness in "stopping" an enemy aircraft. Is that correct?
Sorry, but British is not my first language.
Sorry, but British is not my first language.
I'm going to step out on a limb here and probably get flamed, but when you say "stoppage" I infer that to mean that the weapon was prone to jamming, and that the term has nothing to do with its actual effectiveness in "stopping" an enemy aircraft. Is that correct?
Sorry, but British is not my first language.
Sorry, but British is not my first language.
Stoppages always were a problem with early wing mounted Hispanos.... This led to the belief that the cause of stoppages in the early Spitfires was due to the wings flexing. This may or may not have been a contributing factor as the later Hurricanes which had a stiffer wing had fewer stoppages than the Spits.