Counter-drone on naval vessels: FN Herstal bets on the Sea Defnder weapon station

With the Sea Defnder, FN Herstal has developed a counter-drone system for naval vessels designed to counter threats from aerial and surface drones more effectively. According to the manufacturer, it can neutralise asymmetric threats in particular and is also ideally suited “for use in an effective layered defence system”.

Naval forces – like land and air forces – have been confronted with such asymmetric threats for several years. Recently, however, both their number and their capabilities have developed rapidly. How effective these weapons can be was shown in the Black Sea, for example: there the Ukrainians fought the Russian Black Sea Fleet without deploying ships of their own and even managed to shoot down combat aircraft with the unmanned platforms.

In the foreseeable future, major powers will also incorporate these systems into their concepts for attack and defence and integrate them alongside high-end systems. At present, high-tech and expensive missiles are used against the low-cost unmanned systems. The result is financial loss and the risk of ammunition shortages.

Counter-drone with the 12.7-millimetre machine gun

This is where FN Herstal comes in with the FN Sea Defnder remote weapon station. At sea it can be fitted with the world’s leading NATO machine gun in 12.7×99 millimetre calibre (.50 cal), which achieves a high rate of fire of 1,100 rounds per minute. The Sea Defnder is also available with a choice of day and night cameras, rangefinders, target tracking and gyroscopic stabilisation. It is operated from a protected position, and its performance exceeds that of crewed weapons.

According to FN Herstal, the system can “engage a large number of targets, even over longer periods”. The company cites the .50 calibre cartridge as a further advantage: it is inexpensive and easy to procure, many different armed forces worldwide use it, and almost all major manufacturers of military small-arms ammunition produce it.

This type of ammunition can also engage hard targets. The various projectile types available include, for example, the FN APEI-169 Armour Piercing Explosive Incendiary, which FN Herstal also developed itself and which has great destructive power. The weapon system has no minimum range; the range is adapted to the respective target. The high rate of fire creates a dense shot pattern within a short time, making moving targets more likely to be hit.

According to FN Herstal, it has already secured its first orders. The weapon system was recently selected for the mine countermeasures vessels of the Netherlands and Belgium, which are currently being commissioned, as well as for Brazil’s Tamandaré-class frigates. In a press release, the manufacturer emphasises that the FN Sea Defnder will be “a serious contender both for new ships and for retrofitting existing platforms, from smaller coastal patrol boats to ocean-going supply ships and large combat ships”.

Because the system is modular, new technologies are to be integrated and further developed quickly in future. Customers can also choose between components, for example between different targeting systems.