Lean on the Barrage: The Role of Artillery in Ukraine's Counteroffensive

The much-anticipated Ukrainian counteroffensive has begun, with pushes being made along several axes. As the Ukrainian Armed Forces shift from a largely defensive posture to an offensive one, the employment of artillery must change accordingly.

The use of artillery has been a focus of much analysis during the conflict in Ukraine. Commentary has repeatedly emphasised the importance of the number of systems available, the mass of projectiles being launched by both sides, and the use of uncrewed aerial systems (UAS) for targeting purposes. Such topics are important, but also mask important nuances in the employment of artillery which can be instructive on how the capability can be used to best effect. For the Ukrainian Armed Forces, how to use artillery on the offence to overcome significant Russian defensive positions is crucial to their success. Used correctly, artillery can shatter the will and cohesion of the enemy, offering significant opportunity to seize both ground and the initiative. This is easier said than done and far more complex than simply launching shells in the general direction of enemy positions without due thought. The Russian Armed Forces have repeatedly failed to dislodge Ukrainian forces in defensive positions, as demonstrated by the prolonged assault on Bakhmut. The Russian assault on the city used relentless artillery barrages to attempt to dislodge Ukrainian soldiers and seize the city. And yet, Ukraine was able to maintain a foothold in the city and now appears to be successfully advancing eastwards. This article focuses on massed fires, rather than the precision effect of multiple rocket launch systems like HIMARs, which have been covered elsewhere.

On the Offensive

Offensive action seeks to capture or recapture territory in the pursuit of a tactical, operational or strategic goal. Russia has built a significant network of trenches, anti-tank ditches and bunkers measuring over 800 km in length, and in some cases 30 km deep. It should not be understated how difficult it is to overcome a well thought-out and resourced defensive operation. There are two principal tasks for artillery on the offence. The first is to support manoeuvre forces by suppressing enemy defensive emplacements, thereby preventing direct fire targeting of advancing forces. The second is to counter the enemy artillery which will begin to target the advancing friendly forces. Both tasks are non-discretionary when conducting offensive operations. Appropriate fires planning will ensure that targets are engaged with the right weapon(s), within the rules of engagement and targeting policies. Of course, in active combat, the luxury of a perfectly tailored solution may not be possible, and that which is available must be used.

Artillery is a crucial tool in the Ukrainian arsenal for such manoeuvres. Used alone, it is unlikely to destroy defensive positions; for an artillery shell to collapse a trench, it must land as close as two metres away. The circular error probable (CEP) of a munition is a measure of its precision. A typical 155mm projectile has a CEP of 267 m, which means half of the rounds are expected to strike within 267 m of the target, some way off two metres. With this in mind, artillery must be used in concert with manoeuvre forces. In other words, artillery should be used to allow infantry and armour to assault defensive positions and seize them by keeping enemy soldiers’ heads down and preventing them from engaging advancing forces. Without this concurrent activity, the use of artillery will likely be wasted effort and resource. If an artillery barrage finishes and no ground forces follow immediately to exploit the opportunity, then Russian forces can simply return to their positions. The aim is for soldiers to be able to assault defensive positions as the barrage stops or switches fire, before the defenders can regain their composure.

As well as physical effects, artillery fire can have significant psychological effects on both friendly and enemy troops. For the Ukrainians, the knowledge that enormous firepower is there to back them up as they enter the killing zone of the enemy’s weapons is a crucial confidence boost. For the enemy soldiers being suppressed, the psychological effect of artillery fire falling around you is hard to convey in writing: it is terrifying. The noise, smell and shaking ground of a volley of shells exploding in close proximity provides a very effective distraction while friendly troops advance. Immense fear is a sure-fire way to reduce the combat effectiveness of enemy soldiers. While experiences differ between units, it is recognised that many Russian soldiers lack motivation and morale, and many are fighting against their will, having been conscripted. An artillery barrage will have a deleterious effect on their already limited fighting power. Appropriately applied artillery fire will offer advantage to Ukrainian forces. Equally, Russian fires have the same effect on Ukrainian soldiers.

In an assault, a key consideration is ensuring friendly forces know the artillery plan, and vice versa. The timing of fires, and onto what targets they will fall, must be communicated clearly. Those with responsibility to control the fire and who can ensure that falling rounds are far enough in front of the assaulting troops to avoid fratricide must know the plan and be confident in their ability to communicate with the gun battery. This is especially important if an unforeseen situation arises and the assaulting troops are moving faster or more slowly than anticipated. Adaptation while in contact is important and is not easy to execute. Ukrainian forces, like the Russians, contain a great mixture of experience and ability, and artillery targeting is a technical feat. Getting it right is difficult, while getting it wrong is worryingly easy and could be devastating to friendly forces.

Aside from direct action, there may also be scenarios where artillery might provide a deception plan to distract the defenders and allow an assault elsewhere on the line. As a tactic it is often talked about, but properly resourced deception can be incredibly effective at diverting attention. Putting fire down onto one location to divert Russian resources and distract from an assault elsewhere is a useful and realistic task for the guns.

Desired Effect

In the case of a large counteroffensive, projectile consumption will increase and there will likely be more demand for artillery support than there is supply. Commanders will need to be aware of the availability of fires assets and the level of ammunition stocks, as well as the mixture of ammunition natures – high explosive, smoke and illumination – fuze types and propellant charges. Splinter distances must be understood to keep friendly troops from harm. Artillery projectiles are not all equal in all situations. Shells can be set to explode in the air, on contact with a solid surface or on a time delay after they have buried themselves in the ground. Air burst munitions are effective at damaging soft-skinned vehicles and troops in the open. They are less effective against defensive positions, although they can have a positive impact by keeping defenders’ heads down and therefore unable to observe advancing troops. Ukrainian forces might also make use of precision-guided 155mm projectiles like Excalibur which have been gifted by the US. These are fired from field artillery guns, but target coordinates pre-programmed into the shell before launch and have a CEP of less than 20 m at ranges up to 55 km. However, the quantity of Excalibur is small, and they cost around 60 times more than an unguided shell. If targeting a specific defensive emplacement is deemed necessary to unlock an axis, such munitions can prove effective, and this raises the point that a combination of munitions can be employed to achieve objectives.

Ukrainian best practice must also be maintained. The ability to pass information rapidly from the forward line of troops to command posts and gun batteries using digital applications will continue to prove useful. Equally, the use of UAS to observe enemy dispositions remains important. However, what will become increasingly significant is ensuring that targets are properly prioritised, and fires are massed appropriately to have the desired effect, rather than picking off opportune targets. Sheer weight of fire, properly targeted and exploited, becomes crucial on the offensive.

Logistics and Sustainment

Transitioning from defence to offence requires in-depth planning. This extends further than just targeting. Planners need to consider the movement of guns forward to ensure they can offer adequate support to manoeuvre units. If the forward line of troops outruns the range of the guns, units will have to wait and risk suffering additional casualties. Planning considerations may include likely future gun positions and the fastest or safest route to get there, as well as the amount and mixture of ammunition required at that next location. Moving ammunition from stockpiles to gunlines is an immense task, made all the more complex in Ukraine due to the number of artillery systems in use. Most countries have two or three different howitzer types in their land forces; Ukraine has 14. Ammunition is not created equally and ensuring the right ammunition natures make it to the right gun is important if the shells are to land at the intended location. NATO-standard ammunition is 155mm in calibre, while the bulk of Ukraine’s previous arsenal uses Soviet-standard 152mm ammunition. Ukraine has a mixture of guns, some of which use one and some the other. Moreover, the totality of the systems and their interdependencies must be considered – spares and fuel must remain available.

While the mass of fires is important for non-precision-guided artillery to fulfil its core role, economy of effort must also be considered. Consumption rates of artillery rounds will increase during the shift from defensive to offensive operations. This subject has been covered in detail throughout the conflict, and the continued supply of 155mm ammunition is critical to any continued success. It is not simply a case of firing a constant barrage. Gun barrels do not have an infinite life, and their use must be carefully managed to maximise output. Howitzer barrels have a life of between 1,500–2,500 rounds before they need to be replaced. Photographs of Russian howitzers on social media have shown barrels which have exploded during use. This is a sign of overuse and misunderstanding of capabilities by Russian troops. Such incidents often result in catastrophic injuries to the crew. Maximising the life of barrels and other components as well as 155mm projectiles and securing sustainment of supply is key if Ukraine is to maintain momentum and exploit opportunities to seize ground currently held by Russia. This is easier said than done. The UK is unable to manufacture 155mm gun barrels, and there are few manufacturers in Europe with the capability to do so. More than a third of Ukraine’s artillery systems are out of use at any one time for maintenance and repair. Ukraine’s military planners must be alive to this risk and continue to secure supply from industry and partners.

Conclusion

The shift from defence to offence is not a simple military task and many forces have struggled to make the adjustment in the past, both during training and on operations. Field artillery will continue to be a key capability for both sides. If the Ukrainian military can effectively support its manoeuvre forces with its artillery guns and exploit the nuances within the art of fires, it will provide a significant advantage as its forces undertake one of the more difficult military endeavours.

The views expressed in this Commentary are the authors’, and do not represent those of RUSI or any other institution.

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