As the ongoing war in Ukraine has demonstrated, low-cost drone warfare has arrived on the battlefield. While the modern use of armed drones began in 2000/early-2001, with the arming of an RQ-1 Predator drone with an AGM-114 ‘Hellfire’ missile, It was not until after the September 11 Attacks of that year that the armed Predators went into action.
Aside from large modern armies however, drone combat, as such, did not emerge until the rise of the Islamic State after 2014. In 2016, as the war began to turn against the IS, Iraqi forces started being struck by 40mm grenades dropped by modified civilian drones. Tiny, and very quiet, these drone were able to hover – or ‘loiter‘, to use the military term – over an area, and drop explosives on top of targets on command. This immediately raised alarms, as most armored vehiles, such as tanks, are very thinly armored on their top surfaces.
While the use of civilian drones in combat had been noted previously, those instances only seemed to be in the realm of tactical surveillance and reconnaissance. After the IS ramped up its “micro-drone” campaign, though, “proliferation” began in earnest: expanding outside the Middle East, where Russian forces thwarted an attack on one of their bases in Syria in 2018, drug cartels in Mexico began deploying attack drones in earnest.
In Ukraine, drones for reconnaissance and attack have advanced to the point that the Ukrainians are deploying “bomber” drones carrying up to a 44lbs payload of explosives, while also scoring the first acknowledged air-to-air kill of an advanced fighter, in this case a Mig-29, by a kamikaze drone, via sympathetic detonation.
But the use of small drones has been overshadowed by the use of much larger platforms which, while still “drones”, are not really “tactical” weapons. Much has been made of large drones, such as those used by Azerbaijan in the 2020 Nagorno-Karabakh War, as well as uses by Houthi rebels attacking civilian cargo ships in the Red Sea. The problem with these types of attacks is that they more resemble the use of drones and missiles by major powers…What about the infantry-level use of this class of weapons?
Enter the mortar.
The modern battlefield has seen remarkable technological advancement in the last 120 years, yet one of warfare’s oldest weapons — the mortar — continues to play a crucial role alongside cutting-edge unmanned aerial systems. Both provide indirect fire capabilities, but with significantly different characteristics, advantages, and limitations.
Mortars represent possibly the oldest form of artillery still in active military service, with designs dating back to the 14th century. These simple, high-angle weapons offer several enduring advantages. They’re relatively inexpensive, with basic systems costing under $20,000 and individual rounds priced at $50-$300 depending on sophistication. Modern infantry mortars like the U.S. 60mm M224 can be transported and operated by just two soldiers, providing immediate fire support without complex logistics chains.
The mortar’s high arc trajectory allows engagement of targets behind cover and in defilade positions—a capability that maintains its relevance in urban environments where direct fire weapons face significant limitations. Modern mortars can typically engage targets between 100-8,000 meters depending on caliber, with rounds impacting within 1-2 minutes of fire mission commencement.
In contrast, military drones represent a relatively recent development that has rapidly transformed battlefield dynamics. Systems like the Turkish TB2 Bayraktar or loitering munitions such as the Switchblade provide persistent surveillance capabilities combined with precision strike options. These platforms offer unmatched target observation capabilities, with operators able to positively identify targets before engagement and conduct battle damage assessment immediately after strikes.
Drones typically deliver smaller payloads than artillery systems but with significantly higher precision. Where a mortar might achieve a Circular Error Probable (CEP) of 30-100 meters depending on range and conditions, drones can often deliver munitions with accuracy measured in single-digit meters.
However, the comparative cost structure presents significant disparities. Even relatively inexpensive military drones cost hundreds of thousands to millions of dollars per platform, with sophisticated munitions adding tens of thousands per engagement. This cost difference becomes particularly relevant in sustained operations or against adversaries employing low-cost countermeasures.
The evolution of consumer drones into improvised weapons platforms has dramatically accelerated during the Ukraine conflict, with both sides developing increasingly sophisticated swarm tactics using modified commercial quadcopters and purpose-built FPV (First Person View) drones. These systems typically carry 40mm grenades, modified mortar rounds, or small thermobaric charges, creating an entirely new tactical capability at remarkably low cost.
The basic approach involves forward reconnaissance elements identifying enemy positions, followed by the deployment of drone teams equipped with 5 – 20 small, unmanned systems. These teams position themselves just beyond the range of enemy small arms (typically 1-2km from the target) and then launch multiple drones in rapid succession. Each operator controls a single drone, but their actions are coordinated through a tactical commander who prioritizes targets and sequences attacks.
What makes these swarms particularly effective is their combination of saturation and persistence. Unlike a traditional mortar barrage that might last 2-3 minutes, drone swarms can maintain pressure on a position for 30+ minutes as operators rotate through their inventory of systems. This creates both physical and psychological pressure that conventional indirect fire struggles to match.
The economics are particularly compelling. A basic FPV drone capable of delivering a grenade costs approximately $400 – $1,000, while the grenade itself might cost $50-200. Even accounting for losses, this means an engagement involving 10 drones and 20 munitions might cost less than $20,000 total – comparable to just a few mortar rounds from advanced Western systems.
From a tactical perspective, these drone swarms force defenders to make difficult choices. Activating electronic countermeasures reveals defensive positions and quickly depletes battery systems. Taking cover from aerial threats often exposes personnel to horizontal fire. Moving to alternate positions makes units visible to surveillance drones operating at higher altitudes.
The integration of these swarms with conventional forces represents a notable innovation. Infantry units can now advance with drone teams directly embedded in their formations, allowing for immediate fire support without the coordination delays associated with traditional artillery. When resistance is encountered, the formation pauses while the drone swarm engages, creating a dynamic reminiscent of ancient warfare where archers would soften positions before infantry assault – but with far greater precision and real-time assessment capability.
