VIGIL CONSILIUM
Context. Not headlines.

Uncrewed maritime system

Sea Baby

The Security Service's naval drone — the boat that hit the Kerch bridge in 2023, drove the Black Sea Fleet to Novorossiysk, struck shadow-fleet tankers in 2025 and, in December 2025, put an underwater variant into a submarine at its berth.

Sea Baby Ukraine First documented use July 2023; underwater variant announced December 2025

Status as of
2025-12
Last reviewed
2026-09-28

AssessmentModerate confidence

Recognition context, not a stat sheet. The catalogue covers major publicly documented systems relevant to the conflicts Vigil covers — not an exhaustive order of battle. No quantities, availability or current allocations are recorded.

The record What this system is, where it comes from, who operates it and which of Vigil’s modules it is relevant to — with the evidence each of those rests on.

Fielded Evidence: Documented
Silhouette · not to scale

Record

FamilySea Baby
VariantsSea Baby (surface); Sea Baby with launchers and FPV carriers (2025 variants); Sub Sea Baby (underwater; December 2025)
OriginUkraine
ManufacturerSecurity Service of Ukraine (SBU) programme with Ukrainian industry
EraFirst documented use July 2023; underwater variant announced December 2025
Appears inUkraine–Russia

Conflict relevance

This is the catalogue's single record for this system. It is relevant to the module below; each module's Force Atlas shows how it is used there.

Operators

Ukraine: Operated by the Security Service of Ukraine, in joint operations with the Navy; the SBU's own programme, distinct from the Navy's Magura family. No fleet size recorded.

Battlefield role

Long-range unmanned strike at sea: attacks on warships, port infrastructure, bridges and — from 2025 — sanctioned tankers, and a launch platform for smaller drones, extending Ukrainian reach across a sea in which it has no surface fleet.

Strengths

Range enough to reach Novorossiysk from Ukrainian-controlled coast, a warhead sized for ships and piers, low cost against the value of what it strikes, and a programme that has iterated fast — launchers for missiles and FPV drones in 2025, an underwater variant by December 2025.

Limitations

Vulnerable to gunfire, helicopters and electronic warfare on the run in, so that many are lost per hit; dependent on satellite links and on reconnaissance to find targets at sea; and, for the 2025 tanker attacks, a use whose legal and political consequences are contested. Fleet size and loss rates are not published.

Campaign relevance

Derived: a participant organisation in these campaigns carries a typed equipment association with this system. That is not the same as documented use of the system in the campaign itself.

Visual identification

A low, grey, boat-shaped hull with a small superstructure and sensor mast, seen almost only in SBU release footage; the underwater variant has not been shown in detail.

Documented conflict use

Documented by the SBU from the July 2023 Kerch bridge attack, the 2023 strikes on Black Sea Fleet ships and Novorossiysk, and the 2024 campaign that kept the fleet from the western Black Sea; in 2025, the attacks on shadow-fleet tankers attributed to the type; and on 15 December 2025 the Sub Sea Baby strike on a Kalibr-armed Improved Kilo submarine at Novorossiysk, the first documented underwater-drone hit on a submarine in port, with satellite imagery showing the boat damaged at its berth. Claims are the SBU's own except where imagery supports them.

Related key events

2023 – early 2024Campaign-phase link

Black Sea Fleet pushed from the western Black Sea

Repeated strikes on Sevastopol and losses to naval drones force Russia to relocate most major fleet units eastward; Ukraine's unilateral export corridor consolidates in the fleet's absence.

Assessed as of — 2025-12 Last reviewed — 2026-09-28