Vanguard class

Ballistic missile submarine (SSBN) that has carried the UK's Trident nuclear deterrent continuously at sea since the early 1990s, armed with Trident II D5 missiles. Four boats form the current force pending replacement by the Dreadnought class.

In service since 1993 · 1 operator countries

Compiled from public sources ·primary reference ↗ ·last verified 2026-07-02

15,900

135

crew

Procurement snapshot

Availability & export

UK export-licensed

Subject to UK SPIRE licensing (ECJU); generally available to allied states.

Channel: Government-to-government or direct

Fielded & proven

Limited · 1 operator

In service since 1993. Status: active · ~4 built.

Lifecycle cost (est.)

No public unit price to model from.

Interoperability

Mk 41 VLS-class

Derived guidance from public data — export regime by country of origin, lifecycle from the GAO ~30% acquisition rule. Verify eligibility, pricing and offsets with the manufacturer and your acquisition authority.

Full specifications

Firepower

Armament, payload and guidance.

VLS cells Vertical-launch missile cells on a warship — a proxy for magazine depth. Higher means more missiles before rearming.: 16

Stronger than 77% of submarines
Torpedo tubes Number of torpedo tubes (submarines and some surface ships).: 4

Stronger than 13% of submarines

Physical

Dimensions, weight and crew.

Length Overall length including gun/probe where applicable.: 149.9 m

Naval

Displacement, speed, endurance and diving depth.

Displacement Standard displacement in tonnes — the ship’s size class. Larger hulls carry more but cost more and are less agile.: 15,900 t
Submerged speed Maximum speed while submerged (submarines). Higher is faster underwater.: 25 kn

Stronger than 73% of submarines
Complement Crew size. Fewer eases manning cost; more may indicate a larger, more capable platform.: 135
Propulsion plant Machinery type — nuclear reactor, gas turbine (COGAG), CODAG, diesel-electric, AIP.: 1× Rolls-Royce PWR2 nuclear reactor

Program

Cost, production scale and operators.

Units built Total production run. Higher means proven manufacturing, mature logistics and spares availability.: 4

Stronger than 39% of submarines
Operator countries Number of countries operating the system. More operators means broader support ecosystem.: 1

Stronger than 39% of submarines

Specifications compiled from public BAE Systems and reference sources ↗. Published defense figures are approximations — treat comparisons as directional. Last verified 2026-07-02.

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