Comments by "William Cox" (@WildBillCox13) on "USS Essex - Guide 093 - Part 002 (Fighters)" video.

  1. The Colt Mk12 20mm cannon had several major issues mitigating against its use in aircraft. Standard German and British 20mm types enjoyed greater reliability. This is why service versions of the F86 (excluding the D) were armed, instead, with the .50cal M2 (HB). From everyone's favorite argument mill, Wikipedia: "The Mk 12 was an advanced derivative of the wartime Hispano HS 404 that had been used on British and some American fighter aircraft during World War II. It used a lighter projectile with a bigger charge for better muzzle velocity and higher rate of fire at the cost of hitting power. It entered U.S. Navy and U.S. Marine Corps service in the mid-1950s, replacing the earlier M3 cannon. In service, the Mk 12 proved less than satisfactory. Although its muzzle velocity and rate of fire were acceptable, it was inaccurate and frequently unreliable. Pilots of the F-8 Crusader over North Vietnam, in particular, appreciated the presence of the cannon, but jams and stoppages were common, especially following hard dogfighting maneuvers." The earlier Mk 3 was even worse: "The British version was also licensed for use in the United States as the M1, with both the United States Army Air Corps (USAAC) and U.S. Navy planning to switch to the 20 mm calibre as soon as the gun could be produced in sufficient numbers. In 1941 a very large building program was established, along with the production of ammunition. When delivered, the guns proved to be extremely unreliable and suffered a considerable number of misfires due to the round being lightly struck by the firing pin.[11] The British were interested in using this weapon to ease the demand on production in England, but after receiving the M1 they were disappointed. British wing-mounted fighter weapons by this period were cocked on the ground by the aircraft armourers before flight, the built-in pneumatic cocking mechanism used previously being regarded as unnecessary weight and detrimental to aircraft performance, so any stoppage in flight made the gun unusable until it could be cleared on the ground. The misfires also had the tendency to cause aircraft with wing-mounted guns to yaw away from the wing with the failed gun when the guns were fired, due to the unequal recoil, thus throwing off the pilot's aim."
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