- NATO warships deployed to the Red Sea have used their deck guns to shoot down Houthi drones.
- The deck guns fire cheaper ammunition than expensive surface-to-air missiles.
- Former US Navy officers told BI that the engagements prove this weapon is still very much relevant.
NATO warships deployed to the Red Sea have been using their deck weapons, from autocannons to naval artillery guns, to shoot down Houthi drones over the past few months.
The engagements demonstrate that naval deck guns are not only still relevant but also offer warships a more cost-effective way to destroy drones than expensive surface-to-air missiles, retired US Navy officers told Business Insider.
Earlier this month, the French military released footage of one of its frigates using a deck gun to destroy a Houthi drone above the Red Sea. The weapon appears to be the Italian-made 76mm naval autocannon, in service since the 1960s. It fired several rounds into the distance, causing a target to explode in the sky.
After the first shot, a small object can be seen flying past the line of sight. The French said this was the rubber cover that protects the gun barrel but "still allows for emergency firing," suggesting that the hostile drone was unexpected and particularly close.
The kill marks the latest but not the first disclosure of a NATO warship using its deck gun to take out a Houthi drone, showcasing the value of these weapons in a maritime drone fight. The range of naval guns is typically within around 10 miles, close enough that any targeting failure or misfire could leave the warship dangerously exposed.
📍Red Sea | Interception by a 🇫🇷 frigate of an aerial drone coming from Yemen, threatening maritime traffic.
➡️ Constant vigilance to ensure freedom of navigation and maritime security from Suez to Hormuz. pic.twitter.com/ARGCV6X3JL
In November, the Navy destroyer USS Stockdale was in the middle of an intense, hourslong shoot-out with the Houthis. At one point, a low-flying drone crossed in front of the warship. It was detected late, but a kill order was given, and the vessel's five-inch gun blasted the threat out of the sky.
Vice Adm. Brad Cooper, the deputy commander of US Central Command, said in January when he disclosed the incident that it's a proud moment to destroy a threat with a missile, "but there's a lot of high-fives when you shoot something down with a gun, kind of World War II-style."
The Mark-45 five-inch deck gun mounted on US destroyers and cruisers was first deployed in 1971. The naval artillery gun is made to hit surface, air, and land targets and has a range of roughly 13 nautical miles; it's typically guided by radar against air targets. In its fully automatic firing mode, it can fire up to 20 rounds a minute with an autoloader.
Arleigh Burke-class destroyers carry 600 rounds of conventional ammunition, while Ticonderoga-class cruisers, which have two Mark 45s, can hold 1,200 shells. This is a far greater magazine depth than the air-defense missile capacity.
This class of destroyers is equipped with as many as 96 vertical launching system cells, while the cruisers are equipped with around 120 VLS cells. Not all these launch tubes carry the Navy's Standard Missile interceptors, like the SM-2, SM-3, or SM-6. They are also equipped with land-attack missiles.
While surface-to-air missiles appear to be the main air-defense tool that US and European warships have used to eliminate Houthi drones and missiles, the deck gun engagements suggest the weapon could be useful in future maritime conflicts where drones are prominent.
Bradley Martin, a retired Navy surface warfare captain, said that while the naval deck gun was always intended to be part of a layered defense, the Red Sea conflict shows that this weapon is ideal for destroying small attack drones that fly slower than a cruise missile.
Maritime drones can be launched in large numbers and are relatively cheap compared to other munitions. "A gun provides an inexpensive counter," said Martin, now a senior policy researcher at RAND.
"What we're learning is that having short-range kinetic capability, like a gun offers, is very valuable," he added.
A longer-range kinetic capability, like the SM-2, can strike enemy aircraft or anti-ship missiles some 90 nautical miles away. But with a $2 million price tag, it's a significantly more expensive option than a Mk-45 round for taking out a cheap drone worth a few thousand dollars.
Martin said that deck guns are a good way to get ordnance out quickly and can be used in various ways. A warship, for instance, may track a target via radar or a camera and fire precisely at it; alternatively, air burst rounds can release lots of shrapnel into the air, making it difficult for a drone to pass through.
US warships are armed with other ways to defend themselves at closer ranges as well. These include the Phalanx Close-In Weapon System (CIWS) and Evolved Sea Sparrow Missiles. A US warship had a close call with an incoming missile early in the Red Sea fight that required CIWS employment.
Archer Macy, a retired Navy admiral, said that it's ultimately the job of the vessel's combat system and the operators to best align each weapon with the incoming threat. He noted that while a deck gun is ideal for the smaller, slower targets, it could potentially engage subsonic cruise missiles, too.
Macy, a senior associate at the Center for Strategic and International Studies' Missile Defense Project, said that the Mk-45 has a muzzle velocity of over 2,500 feet per second, meaning the projectile travels at very high speeds.
"It's a lot cheaper than a Standard Missile, and you can put a lot more of them out in a hurry," Macy explained. "And you carry more on your ship."
In an air-defense situation, a warship tends to fire more than one missile at a target and then see if it works to eliminate the threat, and if it doesn't, the ship will move to launch another, Macy said. Instead, the vessel can put out nearly a dozen five-inch rounds in seconds and fill the sky with shrapnel.
"It doesn't all have to be done with missiles," Macy said. "When in doubt, use a gun — if it's appropriate."
