The largest gun attached to any warplane in the world belongs to the new AC-130W Stinger II flying gunship. Its M102 howitzer can fire 105mm high-explosive shells at targets on the ground at a rate of up to ten rounds per minute. Here it is in action:
The video starts with aircrews loading 105mm howitzer shells into the aircraft for a training mission. The M102 is an older Army light field howitzer, designed to provide indirect fire support for troops on the ground. On the ground, the M102 has been replaced by the M119A2 howitzer, which is lighter and has a longer range.
But the older gun suits the AC-130 just fine. As a hulking transport aircraft, it can easily accommodate the heavier gun, and since it fires shells at its targets from close in, range isn’t a problem.
Next, the Stinger II takes off and promptly takes on gas from a nearby KC-135 Stratotanker. The M102 howitzer is manually breech- loaded, with the aircraft crew loading the gun and then removing the empty brass canister. Once the gun is loaded, the aircrews press a button and the gun automatically moves: The gun is likely traversing to line up on a target the onboard gunner has already located on the ground.
Air Force gunships typically circle over targets at high altitudes, drawing lazy circles in the sky to keep the side-firing weapons trained on targets below. AC-130s used to fly lower, but an incident in the 1991 Gulf War saw a shoulder-fired surface-to-air missile shoot down Spirit 03, a AC-130H gunship providing fire support to U.S. Marines fighting in the Battle of Khafji. All 14 people aboard the plane perished. Now, gunships routinely limit flight operations to above the range of shoulder-fired surface-to-air missiles, about 12,000 feet or higher.
The M102 howitzer is easily the largest gun flying on any existing warplane. Most fighters carry automatic cannons in the 20 to 30mm range, mostly for short-range air-to-air combat and strafing ground targets. The 105mm gun is even larger than the A-10 Warthog’s infamous GAU-8/A Gatling gun, although the GAU-8/A has seven barrels and can fire up to 4,000 rounds per minute.
In addition to the onboard howitzer, the AC-130W Stinger II gunships also pack a 30mm GAU-23/A autocannon, the bigger brother to the 25mm cannon on the Army’s Bradley infantry fighting vehicle. And while previous gunships carried only guns and howitzers, recently the Air Force has started equipping them with wing-mounted bombs and missiles.
To that end, Stinger II carries 250-pound GBU-39B Small Diameter Bombs, glide bombs that can travel up to 40 miles before striking their targets, AGM-114 Hellfire anti-tank missiles, AGM-176 Griffin missiles, and GBU-44 “Viper Strike” glide bombs. This arsenal increases the range of the gunship’s weapons from about five to 40 miles, while also providing more flexible options for striking enemies on the ground, particularly when precision targeting is a must. The Stinger II’s precision firepower also permits close air support against enemies operating close to U.S. troops, enabling it to target something as small as a machine gun pit or flatten an entire building.
The Stinger II is a modified Air Force C-130H transport. It’s outfitted with threat-detection equipment designed to warn against ground threats, new navigation, communications, and countermeasures equipment, and an advanced fire-control system. Automation and a shift from guns to standoff munitions means the new aircraft operates with less than half the crew of Gulf War–era AC-130Hs. The Air Force is procuring 12 Stinger IIs to augment existing gunships.