Loitering munitions

The Mini Harpy from IAI is seen here being launched from a truck, although this can equally be done from a naval vessel or helicopter. It has an 8kg shaped-charge warhead and can loiter for 2h. (Photo: IAI)

Lessons from the Caucasus

The 2020 Nagorno-Karabakh conflict highlighted the importance of long-range capabilities on modern battlefields. Loitering munitions contributed to the Azerbaijani victory, resulting in a newfound international desire to obtain, and learn to counter, this type of weapon.

Gordon Arthur

The public perception of loitering munitions figuratively exploded during last year’s Nagorno-Karabakh conflict between Armenia and Azerbaijan, as the latter showed images of one enemy vehicle after another being destroyed from above. Loitering munitions are also being used in Libya, Syria and Yemen.

Azerbaijan relied heavily on Israeli loitering munitions. In 2016, it placed orders for 100 Orbiter 1Ks and 50 Harops. In the six-week conflict, it allegedly also operated SkyStriker and Kargu loitering munitions, as well as Turkish Bayraktar TB2 UCAVs.

The Center for Strategic and International Studies summarised: ‘Azerbaijani drones provided significant advantages in ISR as well as long-range strike capabilities. They enabled Azerbaijani forces to find, fix, track and kill targets with precise strikes far beyond the front lines. UAVs were operationally integrated with fires from manned aircraft and land-based artillery, but also frequently used their own ordnance to destroy various high-value military assets.’

It is impossible to verify what the final toll was, but likely a minimum of 280 Armenian tanks/armoured fighting vehicles, 540 soft-skin vehicles and more than a dozen SAM systems were destroyed or captured, many by loitering munitions or UCAVs. Azerbaijan’s aerial superiority forced the enemy to utilise camouflage and to avoid concentrations of personnel and equipment.


🜂 A table comparing the loitering munitions used during the Nagorno-Karabakh conflict. (Source: Shephard Defence Insight)


Brett Hush, VP and product line GM for tactical missile systems at California-based AeroVironment, gave a concise description of what a loitering munition does. ‘It allows the user to engage targets at greater distances than conventional direct-fire weapons, and with far more accuracy than indirect-fire weapons such as mortars or artillery. Importantly, a loitering munition provides unprecedented flexibility in decision-making, which is especially critical in congested battlegrounds such as urban or semi-urban areas. The loitering munition provides situational awareness of the target area via full-motion video streamed to the fire control unit,’ Hush explained.

Market leaders

Israel is the acknowledged leader in loitering munitions. The director of Israel Aerospace Industries’ (IAI’s) loitering missiles division, who can be identified only as Assaf, told Shephard that the weapon class is best understood as a ‘loitering missile’ rather than a UAV. He explained that IAI pioneered these munitions 40 years ago, with the 160kg Harpy introduced to hit time-critical targets, initially mobile SAM batteries/radars operating somewhere within a large area.

Other weapons, such as guided missiles, need to know a target’s location before being launched, but Harpy loitering munitions can prowl over a large area for up to 9h until a target is identified and then hit it with <1m precision with their 16kg warhead.

The latest version, Harpy-NG, is a third-generation weapon. Next to appear from IAI was the Harop that added an EO/IR sensor to the same Harpy warhead and fuselage. Additionally, the Maritime Harop can be launched from vessels like OPVs and frigates, a cost-effective alternative to anti-ship missiles.

Moving down in scale is the Mini Harpy with dual EO/IR and anti-radiation seekers, while the Green Dragon/Mini Harop is smaller at 15kg. The 6kg Rotem quadrotor is recoverable, only needing its battery replaced before being sent out again. Reflecting an intensifying interest in loitering munitions, IAI reported in February three separate deals totalling more than $100 million for the Rotem and Harop land and naval versions.

One challenge for loitering munitions is the balance between autonomy and having a man in the loop at critical points, Assaf explained, ensuring simplicity but also tactical flexibility. The weapon needs to be intuitive to operate and cost-effective. It must be dramatically cheaper than a surveillance UAV/guided-missile combination, for example.

Typically, loitering munitions are canister-launched, so they do not need runways; they are not often recoverable since they are a munition rather than a UAV. If the weapon is supposed to be recovered, its capability is essentially cut in half in terms of available space, and its warhead will consequently be smaller. Regulatory safety procedures would also be prohibitive in retrieving munitions returning to base.

Moving on, Elbit Systems offers the SkyStriker with an EO/IR payload combined with different warheads that can be exchanged in the field. The OEM said ‘hundreds’ of SkyStrikers have been delivered to customers around the world. A spokesperson stated: ‘SkyStriker enables forces to perform independent ISTAR missions with higher flexibility, while dramatically shortening traditional sensor-to-shooter loops… In comparison with EO/IR missiles, the SkyStriker brings significantly extended ranges and endurance, offering a range of tens of kilometres and endurance of up to two hours.’


🜂 This is the short-range Hero-30 loitering munition, one of the smaller members of UVision’s extensive Hero family. With its launch canister, the Hero-30 weighs 7.5kg and has a 30min endurance. (Photo: UVision)


Thinking about future trends, Elbit Systems predicted: ‘Generally speaking about market trends in this field, we will probably be seeing a wider range of sizes and weights of loitering munitions being introduced to the market, suitable for a variety of different platforms across land, air and sea.’

Aeronautics unveiled its Orbital 1K in 2015, based on the Orbiter 2’s form. Azerbaijan ordered 100 examples in 2016, and apparently 40 were delivered before sales were suspended by the Israeli MoD the following year, due to an investigation into Aeronautics’ involvement in an actual military strike whilst in Azerbaijan to finalise a sales contract. The company’s export licence was later reinstated.

Another Israeli loitering munitions maker is UVision. Its ‘combat-proven’ Hero family spans the Hero-20, Hero-30, Hero-70, Hero-120, Hero-250, Hero-400, Hero-400EC, Hero-900 and Hero-1250 (the numbers refer to the munition’s weight multiplied by ten). A spokesperson told Shephard: ‘Hero systems are the fastest sensor-to-shooter loitering munitions… Each munition can handle different missions ranging from lightweight static or moving targets (such as light-duty vehicles and human targets) to larger fortified or heavily armoured targets such as tanks, enemy air defences and other tactical-strategic objectives.’

UVision said it constantly refines its weapons: ‘Since our systems are highly effective against high-value targets… we are currently in the process of further increasing their lethality, preciseness and immunity to EW and other challenges.’ Indeed, UVision is focusing on ‘additional intelligence-gathering capabilities for performing target acquisition, for battle damage assessment and enhanced reengagement’.

The company recently introduced two new configurations of its Hero training and simulation system. The Classroom configuration provides a scenario generator for multiple trainees, whereas the Portable & Embedded field simulator gives Hero operators hands-on training to maintain proficiency during deployments.

UVision would not disclose identities of its customers, other than to say: ‘Following the Nagorno-Karabakh conflict, we have experienced significant global growth of interest in loitering munition systems.’


🜂 Rafael launched the 3kg Spike FireFly with a 350g fragmentation warhead onto the international market in 2018. This retrievable aircraft is just 400mm high and has a 1km range. (Image: Rafael)


Finally, Rafael offers the Spike FireFly, for which Israel placed an order last year. Operated by a single soldier, it is designed for urban combat and features a dual seeker and target tracker.

Eastern advances

Many countries buy Israeli loitering munitions, but Korea Aerospace Industries (KAI) is seeking collaboration after signing an agreement with IAI on 3 March. The parties stated: ‘As part of the MoU, KAI and IAI are aiming to expand their long cooperation to market loitering munitions to Republic of Korea Army requirements.’

KAI released a promotional video last November illustrating its ambition to combine loitering munitions with helicopters. The video featured a Light Attack Helicopter (LAH) deploying four Green Dragon weapons from canisters mounted on its stub wings. These munitions perform both reconnaissance missions and suppression of enemy air defences, with the operator sitting at a console aboard the helicopter. The LAH can also pass data acquired by the munition’s sensors to a ground-based command centre for further action. Alternatively, the weapon can strike a target with its own warhead. Later in the KAI video, a Surion helicopter launched a swarm of Rotems for an SAR mission.

KAI told Shephard: ‘KAI is carrying out R&D projects for the purpose of technology demonstration for manned-unmanned teaming. We are in discussion with IAI to explore the optimum solution at this moment, including visual demonstration as well as demonstration of integration of loitering munitions with helicopters for operational enhancement.’

Interestingly, KAI exhibited its Devil Killer in 2011, a 25kg loitering munition that performed its first flight in August that year. When asked about its status, the OEM replied: ‘We will take advantage of technologies from the Devil Killer project. However, the development concept depends on the requirements of the Korean army, the expected launch customer.’

Nearby China developed its own version of the Harpy, with multiple units carried on a 6×6 truck. Although little detail is available, it can be assumed the PLA has a variety of loitering munitions in service. Shephard reported last September that a China Electronics Technology Group Corporation subsidiary conducted a test using 48 UAVs similar to the CH-901 launched from a vehicle. The test also launched the same loitering munition from the tail boom of a Bell 206L helicopter.

In 2019, Taiwan exhibited a semitrailer truck containing 12 Chien Hsiang anti-radiation loitering munitions. Taipei is spending $2.54 billion over six years to develop and manufacture 104 Chien Hsiangs to help counter Beijing’s military threat to the island.


🜂 It may look like an IAI Harpy, but Taiwan has developed its own indigenous anti-radiation loitering munition that it calls the Chien Hsiang. It would help suppress Chinese air defences in case the PLA ever attacks Taiwan. (Photo: Charles Au)


Elsewhere, Iran developed the 1.2m-long Qasef-1 and improved Qasef-2K loitering munitions, the latter having an operational radius of 100km, endurance of 100min and a 30kg warhead. It is based on the Ababil-2 UAV airframe, and Houthi rebels have used them against Saudi Arabia to attack Patriot missile battery radars, for example.

Reflecting Turkey’s newfound niche in the global defence industry, STM has manufactured the 1.25m-long fixed-wing Alpagu since 2018. It weighs 3.7kg and has a 5km range. Also in STM’s portfolio is the 7kg and 5km-ranged Kargu quadrotor.

Western innovation

Expanding upon its Switchblade 300, AeroVironment in the US released an extended-range version called the Switchblade 600 in October 2020. It weighs 23kg and can seek out BLoS targets such as light vehicles. Operators can select its direction of attack, angle of attack and stand-off detonation distance.

AeroVironment’s Hush describes the Switchblade 300 as ‘the most widely adopted loitering munition in use today, with more than a decade of continuous combat engagements’, after the US inducted it in 2011. The UK has invested in Switchblade too, according to a March announcement.

To make Switchblade more effective, Hush said AeroVironment is ‘introducing advanced features designed to enhance Switchblade’s ability to operate in hostile RF environments, which could disrupt traditional GPS-aided navigation and command-and-control communications’. He said that ‘today there is a tremendous amount of innovation taking place’ to advance loitering munitions.

He added that the company ‘is expanding flight range and loitering duration, improving sensor capabilities to detect targets at greater stand-off distances and increasing levels of onboard autonomy for automatic target recognition and cooperative engagements’.

In Russia, the Zala Aero Group markets the 12kg Lancet-3 that has a 3kg warhead and 40min endurance. The Lancet-3 has been used against militants in Idlib, Syria. Zala also produces the smaller 5kg Lancet-1 with a 1kg warhead.


🜂 Released last year, the 23kg Switchblade 600 has greater range and endurance than the existing Switchblade 300. The new variant was developed to strike BLoS targets such as light tactical vehicles. (Image: AeroVironment)


Meanwhile, WB Group from Poland makes the 5.3kg Warmate with a 15km LoS range. The Polish military commissioned about 100 units (each comprising ten munitions) in January.

Changing battlefield

The effective pairing of UAVs and loitering munitions by Azerbaijan dramatically illustrated how a new and lower-cost form of air combat can be performed, making attacks more precise and effective. However, the corollary is that low-level conflicts – for example, those between smaller countries – can become a lot deadlier.

Tanks, for instance, have suddenly become vulnerable, forcing many militaries to rethink how they will conduct armoured warfare. As the Nagorno-Karabakh conflict demonstrated, the psychological impact of loitering munitions could perhaps be as fearsome as the warheads they actually carry.

Conversely, the application of these ‘wonder weapons’ should not be overemphasised. Remember that Armenia employed mostly obsolete air defence systems and in inadequate numbers; its EW countermeasures were ineffective too. Indeed, one important lesson from that war is the need for full-spectrum air defence.

Certainly, many militaries will have received ample food for thought as to how they will counter loitering munitions and armed UAVs, and how to rapidly fill defensive gaps among ground units with mobile short-range air defence systems.

In the future, we can expect helicopters to integrate loitering munitions as they give farther reach. At the moment, loitering munitions can be used against ground and sea targets, and perhaps a next stage will be against airborne targets like hovering helicopters.