The incorporation of Artificial Intelligence (AI) in military systems is redefining the conduct of modern warfare. Weapon systems are rapidly getting smarter, nimble, and thus more capable. Loitering Munitions, also commonly known as kamikaze drones, are a recent example in this regard. These are drones with integrated warheads and are designed to loiter for an extended period of time. Such munitions combine inputs from onboard or data-linked sensors and, after input processing, execute actions. The integration of a higher degree of autonomy allows these munitions to exploit vulnerabilities in the enemy’s defences and engage beyond visual line of sight (BVLOS) and even over the horizon (OTH) targets. Besides, loitering munitions can offer significant advantages to naval warfare as well.
Depending upon size, loitering munitions present varying ranges and payloads. They fall in-between drones and cruise missiles and thus offer vast applications in the military domain. Unlike combat drone, which acts as a launch platform for weapons, loitering munitions are weapons in themselves. Similarly, in contrast to cruise missiles, these munitions can loiter for longer duration and display far more flexible flight characteristics than cruise missiles.
The earliest example of loitering munition, called the Harpy drone, was developed by Israel. This kamikaze drone (and its larger version Harop) was designed to hover over a wide area, search out radio emissions, and then strike the source of radio emissions. In concept, the Harpy drone was optimised to suppress enemy air defences (SEAD). These suicide drones were used extensively for the first time by Azerbaijan in the Nagorno-Karabakh conflict. The effective employment of these drones, particularly against the enemy’s air defence systems, facilitated Azerbaijan’s dominance over Armenia throughout the conflict.
Loitering Munitions have operational characteristics which are important for overcoming enemy defences. These munitions possess very low radar cross-section (RCS), which allows them to hide from the enemy’s sensors. Their flight-hovering capability for finding and exploiting the gaps in defences is unique and hard to counter. And these can also be employed in swarms for saturation attacks which can overcome even multi-layer defence. In swarms, these munitions with specialised payloads, i.e. jammer, decoy, etc., can be used in conjunction with suicidal drones to achieve a higher degree of success.
The ongoing Russia-Ukraine conflict has showcased that loitering munitions can be configured for a wide spectrum of targets. Ukraine has used US-origin Switchblade munitions to target Russian military installations in Western Crimea and airbases at Saratov and Ryazan located deep inside Russian territory. Domestically made kamikaze drones have also been used by Ukrainian resistance against Russian forces.
Initially, Russia also used domestic Aero-Kub suicide drones but could not achieve any significant results. Later, Moscow switched to Iranian-origin-modified Shahed-136 kamikaze drones. These have been used quite frequently against Ukrainian military installations and civilian infrastructure. Shahed-136 drones, however, cannot strike mobile targets. Therefore, lancet loitering munition has been employed by Russian forces for targeting mobile military units. These drones may not have played any decisive role in the Russia-Ukraine conflict, but they did have a significant psychological impact on the battlefield.
A distinctive feature of the Russia-Ukraine conflict is the first-ever use of a kamikaze drone in naval combat. In November last year, a Ukrainian Gyruza-M class patrol boat was damaged by a Russian Lancet suicide drone. The incident showcased the employment diversity of these munitions and proved that these weapons could easily be optimised for use in the naval domain.
Loitering munitions can offer key advantages to all dimensions of naval warfare in general and Anti-Surface Warfare (ASuW) in particular. The ability of the loitering munitions to provide real-time surveillance can provide extended situation awareness to the operator and, at the same time, grant target engagement capability without the need for additional assets. Low-tonnage vessels which cannot carry cruise missiles, like Offshore Patrol Vessels (OPVs), Fast Attack Crafts (FACs) and patrol boats, can be equipped with compact loitering munitions for improvement in firepower and situation awareness. Similarly, heavier tonnage vessels, like destroyers and frigates, can be armed with loitering munitions for operational flexibility enhancement. These munitions can fill the gap between deck guns and cruise missiles, both in terms of range and firepower. Thus, these munitions can be used effectively against threats which are too small for cruise missiles or too far for guns. Naval aviation and sub-surface assets can also benefit from dedicated versions of loitering munitions. In sum, these munitions can significantly contribute to reinforcing the sea denial (and, to a certain extent, sea control) capabilities of naval forces.
The employment of loitering munitions in the naval domain has a few limitations as well. First, unlike land-based operations, where the target envelope is wide and easy to exploit, finding targets at sea is very challenging. Therefore, smaller and lower-range munitions will be of limited use – particularly in open seas. Second, these munitions may not be able to penetrate warships protected with multi-layer defences. In particular, close-in weapons systems (CIWS), point defence missiles (PDMs), and even futuristic laser weapon systems (LWS) will pose a major challenge to suicide drones, even in swarm formations. Third, these munitions usually carry limited firepower due to warhead size restrictions. However, these munitions would work effectively against smaller vessels like patrol boats.
Besides operational limitations, loitering munitions also present technical, ethical, and legal complications. A suicidal weapon, flying without limited human control, raises accountability concerns associated with International Humanitarian Law (IHL) and the Law of Armed Conflict (LAC). These munitions rely on AI algorithms which are prone to miscalculations and technical failures. Any misuse of such a lethal weapon can disrupt stability or cause inadvertent crisis escalation. Retainment of human supervisory control can minimise such risks, but it would correspondingly reduce the capability of these systems.
Overall, loitering munitions manifest physically how the incorporation of autonomy can create a new class of weapon system with vastly superior capabilities. This new generation of weapon systems has the potential to challenge traditional assumptions related to war-fighting concepts. As technology evolves further, loitering munitions will find more applications in modern warfare. But it is also important to formulate and implement legal safeguards for ensuring secure and advertent use of such systems. For naval forces, it is crucial to maintain synchronisation with technological evolution so that effective utilisation of new systems can take place.
