The concept of the gun pod came into its prime during and after World War II. "Package gun" installations on US medium and light bombers, such as the B-25 Mitchell and A-26 Invader, were likely the first pods used by the United States military. One of its primary tasks was to suppress ground defenses during attack runs while conducting maritime interdiction, and the extra armament provided additional firepower.
With the rise of missile usage in the post-WWII period many United States aircraft were produced without internal guns, but it was soon found that guns were still needed both for air-to-air combat and close air support. Gun pods offered a simple means of giving aircraft this capability, with no weight penalty on missions where guns were not required.
The United States has developed systems for use both on fixed-wing aircraft and helicopters.
Developed as a pod for high-speed fighter aircraft which lacked a gun, this pod was fitted with a single M61A1 20 mm cannon and 1,200 rounds of ammunition. This weapon is powered by a ram-air turbine, and fires at a fixed rate of 6,000 rpm. However, for this firing rate to be achieved the aircraft needs to fly over 300 mph (480 km/h), and the pod is designed to be optimal at speeds above 400 mph (640 km/h). Its weight, 1,650 lb (750 kg) loaded, also precludes it from many light aircraft. [1] [2]
The pod was designated XM12 (possibly standardized as M12) by the US Army and the same pod was designated SUU-16/A by the US Air Force. It was sometimes mounted on F-4 Phantom aircraft as a stopgap until internal-gun models entered service.
A pod developed, likely for helicopters, fitted with a single M75 40 mm grenade launcher. [3] Some sources also mention this as a system tested on the JOV-1A Mohawk. [4]
A pod developed for both fixed-wing aircraft and helicopters, fitted with a single M3 .50 caliber machine gun. [3] The pod carried 750 rounds of ammunition and provided a pneumatic charging system for the weapon. [5] This system was used on the JOV-1A and UH-1 series of helicopters. [6] [7]
The pod was designated XM14 by the US army and the same pod was designated SUU-12/A by the US Air Force.
Perhaps the most widely used gun pod developed by the US military, fitted with a single GAU-2 7.62×51mm Minigun. [3] This weapon was produced in three generations, with separate designations applied by both the US Army and US Air Force.
The first was the XM18 and SUU-11/A, which featured a standard version of the weapon encased in an aerodynamic pod. This weapon was unmodified and fired at a rate of 6,000 rpm. The fact that the weapon only fed from a drum containing 1,500 rounds of ammunition meant that a slower rate of fire was desired. [8]
The second set of subvariants, designated XM18E1 (and standardized as the M18) and SUU-11A/A, featured an aircraft-to-pod electric connection, allowing aircraft internal power to be used in providing better starting torque, a de-energized solenoid allowing for better round clearing at low rates of fire, and circuitry that allowed for selectable rates of fire. The options were either 2,000 rpm or 4,000 rpm, both significantly lower than the base rate of fire. [9]
The last set of subvariants were designated M18A1 (development of the M18E1) and SUU-11B/A. These featured a slightly higher set of selectable rates of fire, either 3,000 rpm or the high 6,000 rpm. [1] [10]
These pods were used on a wide array of US aircraft, primarily during the Vietnam War, including the A-1 Skyraider, A-37 Dragonfly, AC-47 Spooky, AC-119G Shadow, the T-28 Trojan and the US Navy's OP-2E and AP-2H. It was also tested on the ACH-47A "Guns A-Go-Go" by the US Army and on the UH-1E Iroquois by the US Marine Corps, and were part of standard armament fits for the AH-1 Cobra with both services. [11] [12]
A pod developed by the US Army, likely primarily for helicopters, fitted with two M60C 7.62×51mm machine guns. [3] Does not appear to have been standardized, likely in favor of the M18 series.
Of note, however, was the fact that this system was also tested with the S-2E Tracker by the US Naval Air Test Center, US Naval Air Station, Patuxent River, Maryland. There is no information as to the outcome of these tests, carried out in 1966, which apparently also involved the SUU-11A/A pod mentioned earlier. [13]
Similar to the XM12/SUU-16/A, this pod featured a self-powered variant of the M61A1, designated XM130 (may have been standardized as the M130) by the US Army and GAU-4/A by the US Air Force. This modification allowed its carriage on aircraft that could not meet the speed requirement of the previous unit, and reduced drag by removing the ram-air turbine requirement. This pod was popular for use on the F-4C and F-4D Phantom II aircraft, as well as British FG.1 and FGR.2 Phantom IIs. [2] [14] The pod still has a weight restriction, weighing more than its predecessor at 1,730 lb (780 kg) loaded with 1,200 rounds of ammunition, and still has the fixed rate of 6,000 rpm. [1]
The pod was designated XM25 (possibly standardized as M25) by the US Army and the same pod was designated SUU-23/A by the US Air Force.
A lightweight gun pod fitted with the M197 20 mm cannon, the unit weighs only 586 lb (266 kg) loaded with 300 rounds of ammunition. It has selectable fire rates of either 700 rpm or 1,500 rpm. [15] The pod is self-contained and powered by a Ni-Cad rechargeable battery, with sufficient charge to expend three complete loads before needing to be replaced. [16] This weapon has been tested on the A-37 Dragonfly and OV-10 Bronco. [17] [18]
Developed under Project Pave Claw, the GPU-5/A was designed to adapt the power of the A-10 Thunderbolt II and its GAU-8/A gun to smaller aircraft. The resulting weapon used a smaller version of the GAU-8/A, designated the GAU-13/A, with only four barrels. Podded, the system weights 1,900 lb (860 kg) loaded with 353 rounds of 30 mm ammunition in two helical layers surrounding the gun (for reduction of overall size). The pod is completely self-contained with a rate of fire of 3,000 rpm. [19]
Developed by the US Navy, this pod is fitted with the Mk 11 Mod 5 20 mm cannon, along with 750 rounds of ammunition. [20] This pod is said to have been used on a variety of US Navy and Marine Corps aircraft including the A-4 Skyhawk, F-4 Phantom II, A-7 Corsair II, and OV-10 Bronco. [1] Approximately 1200 Mk 4 Gun Pods were manufactured by Hughes Tool Company, later Hughes Helicopter, in Culver City, California. While the system was tested and certified for use on the A-4, the A-6, the A-7, the F-4, and the OV-10, it only saw extended use on the A-4, the F-4, and the OV-10. In the case of the OV-10, the unit was used by VAL-4, a Navy squadron assigned to Bình Thủy District, Vietnam, and was used extensively for close air support missions.
The M61 Vulcan is a hydraulically, electrically, or pneumatically driven, six-barrel, air-cooled, electrically fired Gatling-style rotary cannon which fires 20 mm × 102 mm rounds at an extremely high rate. The M61 and its derivatives have been the principal cannon armament of United States military fixed-wing aircraft for over sixty years.
The M2 machine gun or Browning .50 caliber machine gun is a heavy machine gun that was designed near the end of World War I by John Browning. While similar to Browning's M1919 Browning machine gun, which was chambered for the .30-06 cartridge, the M2 uses Browning's larger and more powerful .50 BMG cartridge. The design has had many designations; the official U.S. military designation for the infantry type is Browning Machine Gun, Cal. .50, M2, HB, Flexible. It has been used against infantry, light armored vehicles, watercraft, light fortifications, and low-flying aircraft.
An autocannon, automatic cannon or machine cannon is a fully automatic gun that is capable of rapid-firing large-caliber armour-piercing, explosive or incendiary shells, as opposed to the smaller-caliber kinetic projectiles (bullets) fired by a machine gun. Autocannons have a longer effective range and greater terminal performance than machine guns, due to the use of larger/heavier munitions, but are usually smaller than tank guns, howitzers, field guns, or other artillery. When used on its own, the word "autocannon" typically indicates a non-rotary weapon with a single barrel. When multiple rotating barrels are involved, such a weapon is referred to as a "rotary autocannon" or occasionally "rotary cannon", for short.
The Douglas AC-47 was the first in a series of fixed-wing gunships developed by the United States Air Force during the Vietnam War. It was designed to provide more firepower than light and medium ground-attack aircraft in certain situations when ground forces called for close air support.
The M197 electric cannon is a 20 mm three-barreled electric Gatling-type rotary cannon used by the United States military.
The General Electric GAU-8/A Avenger is a 30 mm hydraulically driven seven-barrel Gatling-style autocannon that is primarily mounted in the United States Air Force's Fairchild Republic A-10 Thunderbolt II. Designed to destroy a wide variety of ground targets, the Avenger delivers very powerful rounds at a high rate of fire. The GAU-8/A is also used in the Goalkeeper CIWS ship weapon system, which provides defense against short-range threats such as highly maneuverable missiles, aircraft, and fast-maneuvering surface vessels. The GAU-8/A is produced by General Dynamics.
The General Dynamics GAU-12/U Equalizer is a five-barrel 25 mm Gatling-type rotary cannon. The GAU-12/U is used by the United States, Italy and Spain, which mount the weapon in their attack jets such as the AV-8B Harrier II, airborne gunships such as the Lockheed AC-130, and land-based fighting vehicles. A lighter four-barrel version, designated GAU-22/A, is mounted on F-35 Lightning II fighter jets.
The M230 Cannon is a 30 mm (30×113 mm), single-barrel electrically-driven autocannon, using external electrical power to cycle the weapon between shots. It was designed and manufactured originally by Hughes Helicopters in Culver City, California. As of 2019, it is produced by Northrop Grumman Innovation Systems.
The M134 Minigun is an American 7.62×51mm NATO six-barrel rotary machine gun with a high rate of fire. It features a Gatling-style rotating barrel assembly with an external power source, normally an electric motor. The "Mini" in the name is in comparison to larger-caliber designs that use a rotary barrel design, such as General Electric's earlier 20 mm M61 Vulcan, and "gun" for the use of rifle ammunition as opposed to autocannon shells.
The Gryazev-Shipunov GSh-23 is a twin-barreled 23 mm autocannon developed in the Soviet Union, primarily for military aircraft use. It entered service in 1965, replacing the earlier Nudelman-Rikhter NR-23 and Rikhter R-23.
The General Electric GAU-13/A is a 30 mm electric Gatling-type rotary cannon derived from the GAU-8 Avenger cannon.
A gun pod is a detachable pod or pack containing machine guns, autocannons, revolver cannons, or rotary cannons and ancillaries, mounted externally on a vehicle such as a military aircraft which may or may not also have its own guns.
Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. This can be influenced by several factors, including operator training level, mechanical limitations, ammunition availability, and weapon condition. In modern weaponry, it is usually measured in rounds per minute or rounds per second.
A rotary cannon, rotary autocannon, rotary gun or Gatling cannon, is any large-caliber multiple-barreled automatic firearm that uses a Gatling-type rotating barrel assembly to deliver a sustained saturational direct fire at much greater rates of fire than single-barreled autocannons of the same caliber. The loading, firing and ejection functions are performed simultaneously in different barrels as the whole assembly rotates, and the rotation also permits the barrels some time to cool. Rotary cannons, external or self-driven are used in aircraft over reciprocating bolt autocannons which are more prone to jamming in high g environments. The rotating barrels on nearly all modern Gatling-type guns are powered by an external force such as an electric motor, although internally powered gas-operated versions have also been developed.
The XM214 Microgun is an American prototype 5.56 mm rotary-barreled machine gun. It was designed and built by General Electric. The XM214 was a scaled-down smaller and lighter version of the M134 Minigun, firing M193 5.56×45mm ammunition.
The United States military has developed a number of Helicopter Armament Subsystems since the early 1960s. These systems are used for offensive and defensive purposes and make use of a wide variety of weapon types including, but not limited to machine guns, grenade launchers, autocannon, and rockets. Various systems are still in use, though many have become obsolete.
The Type 730 is a Chinese seven-barrelled 30 mm Gatling gun/rotary cannon CIWS. It has a PLA Navy designation H/PJ12. It is mounted in an enclosed automatic turret and directed by radar, and electro-optical tracking systems. The maximum rate of fire is 5800 rd/m, and the effective range is up to 3 km.
The GAU-19/A is an electrically driven, three-barrel rotary heavy machine gun that fires the .50 BMG cartridge.
An armed helicopter is a military helicopter equipped with aircraft ordnance. Most commonly, it is used for attacking targets on the ground. Such a helicopter could be either purposely designed for a ground-attack mission—in which case it would be more specifically categorized as an attack helicopter—or may have been previously designed for other uses, such as utility, air cargo, aerial reconnaissance, etc., with the weapons mounts being modifications, rather than part of the design of the helicopter. The purpose of the modification to an armed helicopter configuration can be field expediency during combat, the lack of military funding to develop or purchase attack helicopters, or the need to maintain the helicopter for missions that do not require the weapons.
The M75 is a 40mm automatic grenade launcher that was used primarily as an aircraft weapon in United States service and was one of the first weapons to use the high velocity 40x53mm grenade.