Is it time for reform? Why should the Armed Forces of Ukraine transition to divisions and corps?

Calls for reforms in the Ukrainian army and a shift to a divisional system have been growing louder over the past few months.

Hromadske attempted to understand what divisions and corps are, the advantages they offer over the current structure of the Ukrainian army, and whether transitioning to a new management system could be a cure-all in the current situation.

How is the army currently fighting?

The Ukrainian army primarily operates in brigades — tactical military units consisting of 3-7 thousand personnel, which are further organized into regiments, battalions, companies, and platoons.

These units are combined into operational-tactical groups (OTGs), which in turn are part of operational-strategic groupings of troops (OSGVs) that emerged at the onset of the full-scale invasion. There are only two OSGVs: "Khortytsia," responsible for the front from the north of Kharkiv region to the south of Donetsk region, and "Tavria," which oversees the defense of southern Ukraine.

Above these structures are operational commands (OKs), established since 2015. There are four of them: "North," "South," "West," and "East." Each command oversees the brigades stationed in their regions, focusing on their supply, staffing, and training.

All of this forms the Ground Forces — the largest branch of the Ukrainian army, overseen by the General Staff of the Armed Forces of Ukraine.

In summary, the current vertical management structure of the Ukrainian army is as follows: brigade command — OTG command — OSGV command — OK command — Ground Forces command — General Staff.

What is wrong with the current system?

A number of Ukrainian military personnel and experts have been calling for structural changes in the Ukrainian army for several months, primarily advocating for a transition to a divisional-corps management system, as they believe the existing management system is highly ineffective, leading to many failures in troop management at the front.

One of the most telling incidents occurred in April 2024 near Ocheretino, close to Avdiivka, where disorganization in defense management in this area resulted in heavy losses for Ukrainian forces, forcing some to retreat. This led to an uninterrupted advance on Pokrovsk, which continues to this day.

“Who should be blamed for the loss of Ocheretino? The former brigade commander of the 115th brigade, who abandoned positions due to unfitness for combat? Or the commander of the OTU, who failed to organize a rotation in time? Or the commander of the OSGV, who did not supervise it? Or the commander of the OK, which includes the aforementioned brigade? There are four people who must make decisions at the operational-tactical level. Who to hold accountable — it’s unclear,” commented military observer and volunteer Bohdan Myroshnykov on the events of April.

Similar issues later arose in Novohrodivka, where a city with a population of 15 thousand was captured in just three days, and in Selydove.

Ultimately, the existing OTGs and OSGVs, unlike divisions and corps, are temporary structural entities. While some operational-tactical groups have existed since the ATO (for example, OTG "Donetsk"), OSGVs only emerged at the beginning of the full-scale invasion.

What makes divisions and corps better than brigades and OTGs?

A division is considered the basic tactical unit in various types of troops in most armies worldwide. It consists of up to 25,000 personnel and is made up of brigades or regiments.

A corps is an even larger military formation, consisting of approximately 2-4 divisions and can number up to 50,000 servicemen. As of now, there are 5 corps in the Defense Forces: the 9th, 10th, and 11th army corps, the Marine Corps established in 2023, and the 7th Air Assault Corps. Thus, in some instances, the previously mentioned operational management level of the army is supplemented by corps command.

The divisional-corps system indeed has several advantages, which were recently articulated by the commander of the 12th Special Operations Brigade "Azov," Denys Prokopenko:

• unity of command (commanders of divisions or corps can organize combat and special training within their units, personally accountable for the process and quality of training, realistically assess combat capabilities, and accordingly assign tasks to each brigade or regiment);
• initiative (command will be able to manage directly within the established units without attached forces, having all their resources except aviation);
• simplicity (the management process of divisions and corps is easier, allowing for a stable defense to be established);
• effort savings (this type of troop management will enable the expansion of operational zones and defense lines);
• security (with this management, there will be no need for "plugging holes" or "putting out fires" with attached units, which complicates interaction with existing troops);
• reduction of manual management at the tactical level (this will allow the general staff to focus on strategic planning and more pressing tasks, such as strategic defense).

Another "Azov" fighter, deputy brigade commander Bohdan Krotevych, points out that having divisions and corps will enable the higher military leadership to hold commanders accountable for failures at the front or poor decisions.

“This is something we can learn from the Russians. They fight with army corps. They come to the corps commander and ask: 'Why aren’t you advancing?' And he can't say that he didn't assign this or that regiment commander. Because he is the one who appointed and trained him. He will be held accountable. And when he also has criminal liability, unlike us, it would be perfect. Because here, only the soldier is blamed,” says the military officer.

Learning from the enemy

The Russian command transitioned to divisions and corps after the Defense Forces pushed the enemy out of the Kharkiv region and later from the right bank of the Kherson region.

Both in 2014 and in 2022, Russia began its assault on Ukraine using battalion tactical groups (BTGs). At the start of the full-scale invasion, Russia employed just over 200 such BTGs.

This structure had its advantages and disadvantages. On the positive side for the Russians — such structural units can operate autonomously for a certain period, as they comprise infantry, artillery, reconnaissance, and support units. Additionally, BTGs are quite maneuverable, primarily due to their relatively small size.

However, each such group is incapable of conducting large-scale offensive operations precisely because of its small size. Most importantly, due to the concentration of various forces within one group, BTGs are highly vulnerable to losses. A striking example of this was the Russian attempt to cross the Seversky Donets River near Bilohorivka in May 2022.

At that time, the occupiers spent about a week trying to build a crossing over the river for further advances on Lysychansk, but thanks to the effective work of the Defense Forces, nearly the entire Russian BTG attempting to cross the river was destroyed.

Heavy losses for the Russian army and a series of defeats on the battlefield led the Russian leadership to first announce "partial mobilization," and subsequently to create two additional military districts and several divisions.

Currently, the Russian army has deployed several large military formations in Ukraine — these are the "North," "South," "West," "East," "Center," and "Dnipro" groupings. Above them are the mentioned military districts, which have in their disposal combined arms armies, corps, and divisions, while references to BTGs have nearly vanished from reports of the Russian Ministry of Defense.

However, it is also not advisable to idealize the enemy's command structure, as the presence of the aforementioned combined arms armies, districts, and small separate military units on the battlefield creates its own problems for the Russians.

Will divisions and corps save the Ukrainian army from chaos?

At the end of November 2024, “Suspilne” and “Ukrinform,” citing their own sources, reported that the Armed Forces of Ukraine planned to transition to a “corps - brigade” system by the end of the previous month.

Journalist sources explained that this system would significantly save human and material resources. In contrast, a transition to a “corps - division” system would reportedly require substantially more human, financial, and material resources, which Ukraine cannot afford at this time.

However, several factors may hinder such a plan. For instance, the director of the “Come Back Alive” fund and military analyst Taras Chmut pointed out that transitioning to such a management system under current conditions is possible, but it should