Colt Mk 12 cannon
Encyclopedia
The Colt-Browning Mk 12 was a 20 mm cannon
widely used by the United States Navy
after World War II
.
and British
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 Navy's 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 dogfight
ing maneuvers.
Nevertheless, the Mk 12 was standard cannon armament on gun-armed Navy and Marine Corps fighters from the early 1950s to the early 1960s, including the F4D Skyray
, F3H Demon
, A-4 Skyhawk
, F-8 Crusader
and early Navy versions of the A-7 Corsair II
. The Air Force version of the Corsair II, the A-7D, had a six-barreled M61A1 rotary 20mm cannon, as did the final Navy A-7E model.
Cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
widely used by the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
Development
The Mk 12 was an advanced derivative of the wartime Hispano HS 404 that had been used on a variety of AmericanUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
fighter aircraft
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. It used a lighter projectile with a bigger charge for better muzzle velocity
Muzzle velocity
Muzzle velocity is the speed a projectile has at the moment it leaves the muzzle of the gun. Muzzle velocities range from approximately to in black powder muskets , to more than in modern rifles with high-performance cartridges such as the .220 Swift and .204 Ruger, all the way to for tank guns...
and higher rate of fire at the cost of hitting power. It entered U.S. Navy and U.S. Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
service in the mid-1950s, replacing the Navy's 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
F-8 Crusader
The Vought F-8 Crusader was a single-engine, supersonic, carrier-based air superiority jet aircraft built by Vought for the United States Navy and the U.S. Marine Corps, replacing the Vought F7U Cutlass...
over North Vietnam
North Vietnam
The Democratic Republic of Vietnam , was a communist state that ruled the northern half of Vietnam from 1954 until 1976 following the Geneva Conference and laid claim to all of Vietnam from 1945 to 1954 during the First Indochina War, during which they controlled pockets of territory throughout...
, in particular, appreciated the presence of the cannon, but jams and stoppages were common, especially following hard dogfight
Dogfight
A dogfight, or dog fight, is a form of aerial combat between fighter aircraft; in particular, combat of maneuver at short range, where each side is aware of the other's presence. Dogfighting first appeared during World War I, shortly after the invention of the airplane...
ing maneuvers.
Nevertheless, the Mk 12 was standard cannon armament on gun-armed Navy and Marine Corps fighters from the early 1950s to the early 1960s, including the F4D Skyray
F4D Skyray
The Douglas F4D Skyray was an American carrier-based supersonic fighter/interceptor built by the Douglas Aircraft Company...
, F3H Demon
F3H Demon
The McDonnell F3H Demon was a subsonic swept-wing United States Navy carrier-based jet fighter aircraft. After severe problems with Westinghouse J40 engine that was ultimately abandoned, the successor to the McDonnell F2H Banshee served starting in 1956 redesigned with the J71 engine...
, A-4 Skyhawk
A-4 Skyhawk
The Douglas A-4 Skyhawk is a carrier-capable ground-attack aircraft designed for the United States Navy and United States Marine Corps. The delta winged, single-engined Skyhawk was designed and produced by Douglas Aircraft Company, and later McDonnell Douglas. It was originally designated the A4D...
, F-8 Crusader
F-8 Crusader
The Vought F-8 Crusader was a single-engine, supersonic, carrier-based air superiority jet aircraft built by Vought for the United States Navy and the U.S. Marine Corps, replacing the Vought F7U Cutlass...
and early Navy versions of the A-7 Corsair II
A-7 Corsair II
The Ling-Temco-Vought A-7 Corsair II is a carrier-based subsonic light attack aircraft introduced to replace the United States Navy's Douglas A-4 Skyhawk, initially entering service during the Vietnam War...
. The Air Force version of the Corsair II, the A-7D, had a six-barreled M61A1 rotary 20mm cannon, as did the final Navy A-7E model.