Toloka TLK-150

Ukraine's small semi-submersible underwater strike drone, designed to approach targets with its hull submerged and only a slim sensor-and-communications mast exposed.

Overview

The Toloka TLK-150 is the smallest publicly described member of Ukraine's Toloka underwater-drone family. It is a compact uncrewed underwater vehicle (UUV) intended for one-way maritime strike missions against ships below the waterline, especially in the Black Sea context created by Russia's full-scale invasion of Ukraine. The design's defining feature is not deep-diving endurance but low surface signature: the hull runs submerged while a narrow mast carries navigation, sensor and communications elements.

Open-source reporting identifies the TLK-150 as Ukraine's first publicly disclosed indigenous UUV design. H I Sutton's 2023 Naval News profile described it as a new Ukrainian underwater weapon concept aimed at Russian Navy vessels, while later Ukrainian defense reporting treated it as part of a broader Toloka family that also includes larger TLK-400 and TLK-1000 designs. No source in the available public record confirms that the TLK-150 has entered Ukrainian Navy service, received a production order, or been used in combat.

Development

The TLK-150 first appeared publicly around April-May 2023 at the launch of Brave1, Ukraine's government-backed defense-technology coordination platform. Naval News reported on 10 May 2023 that the full-size TLK-150 model or prototype was the first indigenous Ukrainian UUV to be revealed. A later Kyiv Post report described the system as a Brave1 project, still at prototype stage, and said production was expected within weeks; that 2023 production expectation is not corroborated by later sources and should be treated as unfulfilled or unverified.

The program reappeared in public in February 2025, when an externally redesigned TLK-150 was shown in a video released during the "Support Ukraine" summit in Kyiv. Defense Express assessed that the new hull looked closer to a serial-production model than the 2023 prototype, with the motors moved from mid-body stabilizers to the tail and the center keel removed. Militarnyi likewise interpreted the redesign as evidence that sea trials may have been underway, but neither source confirmed a formal test record, service entry, or order.

By September 2025, reporting at Brave1 Defense Tech Valley in Lviv referred to Toloka as a developer or company exhibiting its own underwater systems. UNITED24 Media, RBC-Ukraine and Defense Express described a wider Toloka family, but no source names a parent legal entity, founders, investors, or subsystem suppliers beyond the Toloka name.

Design & capabilities

The TLK-150 is a small semi-submersible UUV with electric twin-motor propulsion. Public reporting consistently gives the TLK-150's length as 2.5 m, range as up to ~100 km, and payload as 20-50 kg of explosives, although these remain claimed figures rather than independently verified performance data. Defense Express lists the 2.5 m length, ~100 km range and 20-50 kg payload range, matching earlier Kyiv Post reporting on the prototype.

The vehicle's mast is its main exposed element. Reported mast equipment includes a day camera, thermal imager, GPS antenna and communications antenna, while the body remains underwater. Naval News assessed in 2023 that the mast and keel arrangement could support close-inshore reconnaissance or human-in-the-loop navigation and aiming, but that was analysis rather than a confirmed manufacturer statement.

The 2023 prototype had a visibly improvised and unconventional layout: twin thrusters on small wing-like stabilizers, a large keel, a separate rudder and forward dive planes. The February 2025 redesign moved propulsion and control surfaces aft, removed the large central keel and produced a smoother, more torpedo-like body. Militarnyi characterized the updated shape as no longer resembling a technology demonstrator, but the public evidence still supports a prototype or pre-serial status, not confirmed operational service.

A sourcing discrepancy surrounds a 2025-reported smallest-class Toloka spec sheet labeled "TLK-200." Defense Express and RBC-Ukraine reported TLK-200 figures including 2.9 m length, 0.2 m hull diameter, up to 15 kg payload, up to 15 days endurance, up to 300 m operating depth, satellite communications with frequency-hopping claims, GNSS plus AI-assisted inertial navigation, and optical/thermal targeting. No available source establishes whether TLK-200 is a renamed or revised TLK-150, a separate smallest-class model, or a reporting inconsistency; those TLK-200 figures should not be treated as verified TLK-150 specifications.

Variants

The Toloka family is publicly described in several tiers, but the exact relationship among the designations is not fully settled.

• TLK-150: the original small 2.5 m semi-submersible UUV, publicly shown in 2023 and externally redesigned by February 2025.
• TLK-200: a 2025-reported smallest-class Toloka designation with a 2.9 m hull and different payload/endurance figures; its relationship to TLK-150 is not publicly established.
• TLK-400: a larger model first described in 2023 as a 4-6 m hull with up to 1,200 km range and up to 500 kg payload; later 2025 reporting associated the TLK-400 label with a conflicting 12 m length figure, which remains unresolved in public sources.
• TLK-1000: the flagship large Toloka design, described as up to 12 m long with up to 2,000 km claimed range and up to 5,000 kg payload; it was shown publicly as a large unit at Brave1 Defense Tech Valley 2025, according to Kyiv Independent.

Combat record / operational use

No combat use of the TLK-150 is publicly established. The available sources do not report a confirmed strike, operational deployment, battlefield loss, unit assignment, or Ukrainian Navy service-entry milestone for the TLK-150 or any other Toloka-family drone.

That absence matters because the system is often discussed in the context of Ukraine's successful surface-drone campaign in the Black Sea. Naval News framed the TLK-150 as a potential weapon against Russian Black Sea Fleet vessels, including ships associated with Kalibr cruise-missile launches, but public reporting through the 2025 Toloka exhibition cycle does not attribute any operational attack to the type. RBC-Ukraine described the larger TLK-1000 and TLK-400 as prototypes around the 2025 exhibition, reinforcing that the family remained publicly unproven.

Advantages

• Low exposed signature: the submerged hull and narrow mast should be harder to detect visually or by radar than a surface USV, as emphasized by Naval News.
• Compact size: the 2.5 m hull should be easier to transport, conceal and launch than larger Ukrainian UUV concepts, although launch arrangements are not publicly established.
• Below-waterline attack concept: the mission profile targets a vulnerable part of ships that surface drones cannot engage in the same way.
• Ukrainian development base: Toloka emerged from the Brave1 defense-tech ecosystem, which was created to accelerate domestic wartime innovation.
• Design iteration: the 2025 redesign suggests continued engineering work beyond the 2023 demonstrator stage, even though service entry is not confirmed.

Drawbacks / limitations

• No confirmed service record: no public source verifies production, a Ukrainian military operator, combat use, or operational deployment.
• Shorter reach than larger Toloka concepts: the TLK-150's claimed up to ~100 km range is tactical compared with the TLK-400 and TLK-1000 claims.
• Communications constraint: the mast must expose antennas and sensors above the surface, limiting the pure underwater stealth benefit.
• Unverified performance: payload, range, autonomy, depth and endurance figures are public claims or outlet-reported specifications, not independently validated data.
• Sourcing instability: the TLK-150/TLK-200 designation issue and conflicting TLK-400 length figures indicate that public specifications remain fluid.

Counterparts

• Marichka (UA heavy UUV)
• Sea Trident (UA XL-UUV)
• Sea Baby (UA surface USV)

Toloka occupies the small underwater end of Ukraine's naval-drone ecosystem. Compared with Marichka and Sea Trident, it is a lighter, shorter-range UUV concept; compared with Sea Baby, it trades the proven surface-attack pathway for a less mature underwater approach. Naval News described the TLK-150 as predating other publicly disclosed Ukrainian indigenous UUV designs, but not as a fielded combat system.

Outlook

The TLK-150 remains a watch item rather than a confirmed fielded weapon. Its military relevance would rise sharply if Ukraine confirms serial production, naval adoption, or a successful operational strike; without that, the public record supports only a prototype or pre-serial assessment. The February 2025 redesign is meaningful because it shows maturation from the first Brave1 display model, but the absence of orders, unit assignment or combat evidence keeps the program below the evidentiary threshold of Ukraine's better-documented surface-drone systems.

The most important near-term indicators are an official Ukrainian Ministry of Defense or Navy statement on service entry, clarification of whether TLK-200 supersedes or differs from TLK-150, and any verified operational use of Toloka-family systems. The larger Toloka variants may draw more attention because of their claimed range and payload, but the TLK-150's compact size could make it the family member most plausible for early limited production if the design proves reliable.

Key specifications

Sources

1. Naval News — "Innovative Submarine Drone Is Ukraine's New Weapon Against Russian Navy." https://www.navalnews.com/naval-news/2023/05/innovative-submarine-drone-is-ukraines-new-weapon-against-russian-navy/
2. Kyiv Post — "Ukraine Develops Underwater Drone to Attack Russian Ships." https://www.kyivpost.com/post/17551
3. Defense Express — "Ukraine Shows Its Underwater Kamikaze Drone: Improved TLK-150 Revealed." https://en.defence-ua.com/weapon_and_tech/ukraine_shows_its_underwater_kamikaze_drone_improved_tlk_150_revealed-13656.html
4. Militarnyi — "Ukrainian Underwater Drone Toloka Is Being Updated: What's New in the TLK-150 Model." https://militarnyi.com/en/news/ukrainian-underwater-drone-toloka-is-being-updated-what-s-new-in-the-tlk-150-model/
5. UNITED24 Media — "Ukraine's Massive Underwater Drone Toloka Unveiled at Brave1 Defense Tech Valley 2025 in Lviv." https://united24media.com/latest-news/ukraines-massive-underwater-drone-toloka-unveiled-at-brave1-defense-tech-valley-2025-in-lviv-11798
6. Defense Express — "Secrets of Ukraine's Toloka Naval Drones: What the New Underwater Family Can Do." https://en.defence-ua.com/weapon_and_tech/secrets_of_ukraines_toloka_naval_drones_what_the_new_underwater_family_can_do-15898.html
7. RBC-Ukraine — "Inside Ukraine's Toloka Underwater Drones." https://newsukraine.rbc.ua/news/inside-ukraine-s-toloka-underwater-drones-1758473279.html
8. Kyiv Independent — "Ukraine Showcases Underwater Drones with 2,000 km Strike Capability." https://kyivindependent.com/ukraine-showcases-underwater-drones-with-2-000-km-strike-capability/

🔒 The Analyst Section on Toloka TLK-150 is for BattlePolicy Pro members. Below the line: procurement and contract history, the suppliers and companies behind the system, our head-to-head analyst view of the systems it actually competes with, and the BattlePolicy assessment note. Unlock the full file with BattlePolicy Pro →