Shipping container-mountable guns offer plug-and-play naval defense

Pirates attacking cargo ships might be in for a surprise in the near future as BAE Systems shows off its Sea Tridon family of 40-mm guns at the Euronaval 2026 exhibition in Paris. The systems are designed to be installed as easily as a shipping container.

Between the geopolitical situation and the emergence of new technology and strategies, military architecture is in a state of flux not seen since the introduction of jet propulsion and modern electronics. The rapid development of drones with their swarming tactics requires a whole new approach to firepower that can neutralize mass threats without emptying ammunition stockpiles and busting the bank. In addition, there is an increasing emphasis on developing systems that are modular, allowing them to be quickly adapted and scaled to meet future needs.

Based on the Bofors 40 mm L/70 medium-caliber, rapid-fire cannon that was introduced in the 1930s, the Sea Tridon is the result of almost a century of technological evolution, including the use of new materials; pre-fragmented, programmable, proximity-fused ammunition; and digital command and control interfaces.

It's also the result of a bit of lateral development. The guns were originally designed for sea duty but were adapted for land use in 2023 to deal with drones and loitering munitions that can circle about looking for targets. Now, they're going back to sea as the Sea Tridon family.

According to BAE Systems, Sea Tridon consists of four configurations.

The basic one is the Bofors 40 Mk 4 Naval Gun, which is a lightweight, fully automated cannon that can be directly integrated into a warship's central combat systems.

The basic Sea Tridon has much more independence thanks to its integrated electro-optical fire-control system, so it can be mounted in ships that don't have their own command system.

Meanwhile, Sea Trinity is a complete stand-alone Close-In Weapon System (CIWS) with programmable ammunition and its own radar system, so the Captain effectively only has to give the order to fire.

All family members are designed to be rapidly installed on warships without having to reconstruct the whole vessel, but the most intriguing variant is Sea Tridon^C, which looks like an automated gun turret mounted on top of a small shipping container – which is what it is. The idea is that such a highly portable system can be quickly installed on auxiliary vessels, patrol ships, and merchant marine ships.

In other words, it conjures the picture of a pirate boat off the Horn of Africa or the Straits of Malacca bearing down on a container ship only to see one of the containers on the top of the stack mounting a gun. Under current law, it's extremely difficult to arm private ships against pirates or state actors; systems like Sea Tridon^C can, in times of high threat, be installed aboard merchant ships if they are carrying naval or coast guard personnel to crew the guns.

"The maritime threat landscape is evolving rapidly, creating a growing need for flexible and effective protection solutions," said Lena Gillström, President of BAE Systems Bofors. "With the Sea Tridon, navies and maritime operators can select the capability level that best meets their operational needs while benefiting from a common platform, proven technology and advanced programmable ammunition."

Source: BAE Systems