Feb 18, 2025

A new report from the UK defense thinktank RUSI is a trove of information gleaned from interviews with Ukrainian military personnel in frontline units. The most obvious conclusion: this is a drone war, and using drones effectively for both offense and defence is critical for armies going forward.

A key finding is that tactical drones are inflicting roughly two-thirds of Russian losses. In other words, they are twice as effective as every other weapon in the Ukrainian arsenal put together. This is a remarkable turnaround for weapons which did not officially exist in the Ukrainian military at the start of the war. It is also remarkable to see this sort of analysis from RUSI.

Conservative Thinking

RUSI, full name The Royal United Services Institute, describes itself as ‘the world’s oldest and the UK’s leading defence and security think tank’ having been founded by the Duke of Wellington in 1831. RUSI enjoys a cordial relationship with the British military establishment and does not jump on to every passing technology bandwagon. Rather than interpreting every new development as a possible revolution, they place it in the larger military context of gradual evolution.

Perhaps a sign of RUSI’s conservativism is that they generally decline to even use the term ‘drone’ and prefer to talk about ‘UAVs’ or Uncrewed Air Vehicles.

Previous RUSI reports have downplayed the role of drones. In particular, RUSI have highlighted the high rate of drone losses in conflict. In 2023 they reported Ukraine was losing an alleged 10,000 drones per month, largely to Russian electronic warfare, to convey the limitations of these systems. Their reports have largely countered the enthusiasm of drone believers who insist that drones have changed everything.

In Tactical Developments During the Third Year of the Russo–Ukrainian War the tone has not changed, and the authors are still critical of drone performance:

“Tactical UAVs have significant limitations. Between 60 and 80% of Ukrainian FPVs fail to reach their target, depending on the part of the front and the skill of the operators. Of those that do strike their targets, a majority fail to destroy the target system when striking armoured vehicles. The success rate in wounding infantry is high. Furthermore, there are long periods where either EW or the weather significantly degrades UAV operations. “

This would suggest that drones are not effective. But the next line changes everything:

“Despite these limitations, tactical UAVs currently account for 60–70% of damaged and destroyed Russian systems.”

This supports previous Forbes reporting that small drones, and in particular FPVs, are destroying a high percentage of Russian vehicles. It is also clear that drones are causing a high proportion of casualties among Russian personnel.

Even given this statistic, RUSI favor traditional weapons especially artillery, as they go on to explain.

Drones And Artillery And Expensive Tastes

“The above figure must be read in the appropriate context,” continues the report, saying that Ukrainian officers “emphasised that UAVs alone were inadequate and that they were most effective when used in combination with artillery.”

As an example, they authors describe how much easier it is to destroy tanks with special artillery rounds than drones: “a fires officer described the hours it had taken to plan and eventually immobilise a tank using FPVs, compared with an engagement where a platoon of Russian tanks were manoeuvring and, having located them with a drone, he fired five BONUS shells at them, knocking out all three tanks within two minutes.”

This too needs to be read in the appropriate context. BONUS is a smart 155mm artillery round which dispenses two submunitions over the target area. These seek targets with smart sensors, and, when they find one, fire a slug of high-velocity metal at it – as seen in this video from Ukraine in 2022. BONUS is highly capable, but it is not cheap. In 2019, the U.S. Army paid around $58,000 each for a batch of 1,266 of them.

FPVs cost around $500 apiece or about 1% as much.

The big difference though is in the support needed. A BONUS round has to be fired from a 155mm howitzer. The current towed version, the M777, costs something over $3 million, while the U.S. Army’s M109A7 Paladin self-propelled version is more like $6 million.

So, using BONUS rounds from a howitzer rather than FPVs is quicker and easier, in the same way that commuting to work is quicker and easier if you have a private helicopter. No surprise that commanders would like to have the more expensive option if it is available, but the affordability is an issue.

It is also worth noting that FPV development and adoption was driven largely by the soldiers themselves, often in the face of objections by senior officers, and many drones are still provided by fundraisers. Commanders from the pre-drone age may still prefer traditional arms.

More seriously, artillery pieces are increasingly vulnerable to strikes from enemy drones, as the RUSI report acknowledges. Lose a gun and you lose all the ammunition it is carrying, and the ability to fire any more shells. An artillery piece which gets knocked out after a few weeks use is of limited use. FPVs, which do not require expensive launch apparatus but take off from a couple of bricks, have no such vulnerability and there are tens of thousands of capable drone operators.

Drones Impacting Reconnaissance, Logistics, Medical Evacuation

The report acknowledges that drones are having major effects on other aspects of the conflict, noting simply at one point that: “The conduct of reconnaissance for both Russian and Ukrainian forces has been almost exclusively conducted by UAVs.”

This is a huge change. Armies, including the U.S. and U.K., have specialist reconnaissance units with light vehicles and the ability to conduct operations close to the enemy on foot. In the current war, this capability may start to look obsolete. Further, the drones see deeper and in more detail than was previously possible:

“The aggregate consequence of this dense and overlapping network of UAVs is battlefield transparency within 3 km of the line of contact, with diminishing density of observation out to 15 km of depth…. commanders can generally task reconnaissance capabilities with reasonable fidelity and latency out to 40 km of depth.”

Drones are also having a real impact on logistics, because they can attack supply lines on a massive scale. A partial solution is to switch to drone delivery: “It has even proven possible on occasion for a unit’s chefs to prepare fresh food for units and for this to be delivered in packages via UAVs to dispersed elements of the force.” Drone-delivered fast food is becoming not just a reality but a necessity.

Pervasive drone observation and strike also makes medical evacuation virtually impossible: “Put simply, existing medical doctrine is not executable under modern combat conditions.” – for the troops involved, this may be the most significant change. The lack of medical support may drive a steady shift of soldiers away from the frontlines to be replaced as far as possible by drones.

Lessons For NATO

The report draws several conclusions relating to various aspects of the campaign, including the need to improve Ukrainian morale with better support measures. They also talk about hardware, in particular for more artillery ammunition, noting that Ukraine received about 1.5 million 155mm shells in 2024 and this number needs to be increased. Such shells cost about $3,000 each for the most basic version, the U.S.-made high-explosive M795.

Ukraine also built a around 1.2 million drones in 2024. Given that these destroyed at least twice as much Russian hardware as a similar number of artillery shells, at a fraction of the cost, they might look a more fruitful area for expansion. As the report notes, Ukraine is now starting to deploy ‘wire guided’ drones controlled via a fiber-optic cable which are invulnerable to jamming, and these are likely to increase the hit rate considerably in the coming year. Further drone developments are likely, artillery developments are likely to be incremental.

Finally, the report highlights the urgent need for tactical drone protection for NATO countries:

“Without counter-UAS capabilities, NATO militaries risk seeing high quality troops and equipment rapidly suffering losses for want of protection, when such effective protection is eminently achievable.”

The report suggests that automated gun turrets may be the solution to drone attacks. How well these will work in action is yet to be seen. The current conflict has demonstrated how easily even high-end Western tanks can fall prey to FPVs.

This is only a preliminary report. The conflict in Ukraine is changing all the time and the technology is evolving fast. But the direction of travel seems increasingly clear and it involves drones.

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David Hambling

https://www.forbes.com/sites/davidhambling/2025/02/18/new-report-drones-now-destroying-two-thirds-of-russian-targets