Loitering Munition

A loitering munition is an emerging weapon system category in which the munition loiters around the target area for some time, searches for targets, and attacks once a target is located. Loitering munitions enable faster reaction times against concealed or hidden targets that emerge for short periods without placing high-value platforms close to the target area, and also allow more selective targeting as the actual attack mission can be aborted.

Loitering munitions may be as simple as an unmanned aerial vehicle (UAV) with attached explosives that is sent on a potential kamikaze mission, and may even be constructed with off the shelf commercial quadcopters with strapped on explosives.

Purpose built munitions are more elaborate in flight and control capabilities, warhead size and design, and on-board sensors for locating targets. Some loitering munitions use a human operator to locate targets whereas others, such as IAI Harop, can function autonomously searching and launching attacks without human intervention.

Some loitering munitions may return and be recovered by the operator if they are unused in an attack and have enough fuel, in particular this is characteristic of UAVs' with a secondary suicide mission. Other systems, such as Delilah or IAI Harop, don't have a recovery option and are self-destructed in mission aborts.

Loitering munitions fit in the niche between cruise missiles and unmanned combat aerial vehicles (UCAVs).

Whereas some cruise missiles, such as the Tomahawk, have the ability to loiter and have some sensory and remote control features, their primary mission is typically strike and not target acquisition. Cruise missiles, as their name implies, are optimized for long-range flight at constant speed both in terms of propulsion systems and wings or lifting body design and are often unable to loiter at slow fuel-efficient speeds which significantly reduces potential loiter time even when the missile has some loiter capabilities.

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