Delta IV-class submarine

The Delta IV-class submarine is a Soviet-designed, Russian-operated nuclear-powered ballistic missile submarine class built at Sevmash from 1985 to 1992. NTI says the Russian Navy still fields seven boats in the Northern Fleet, and the class carries 16 SLBMs plus 533 mm torpedo tubes.

Various Conflicts🏳️ Unspecified

Delta IV-class submarine, Nuclear-powered ballistic missile submarine class, Naval Systems

Image source: Submarine Delta IV class.jpg

Profile

Origin: Soviet Union
Built by: Sevmash
Built in: Soviet UnionRussia
Type: Nuclear-powered ballistic missile submarine class
Service note: 1985-present
Designer: Rubin Central Design Bureau for Marine Engineering
Designed: 1975
Produced: 1985-1992
Number built: 7

Also Known As

Project 667BDRM
Project 667BDRM Delfin
667BDRM Delfin
Delfin-class submarine
Delta-IV
Delta IV-class submarine

submarine nuclear-powered ballistic missilestrategic deterrence

Specifications

Length: 167 m
Beam: 11.7 m
Draft: 8.8 m
Displacement: 11,740 tons surfaced; 18,200 tons submerged
Speed: 13-14 knots surfaced; 22-24 knots submerged
Armament: 16 R-29RM missiles and 4 x 533 mm torpedo tubes
Propulsion: 2 pressurized-water reactors and 2 steam turbines
Crew: 130

Service And Conflict Use

Service History

In service: The class entered Northern Fleet service in 1985, and NTI still describes seven Delta IV boats as active Russian Navy assets based at Yagelnaya Bay.
Used by: Soviet Navy, Russian Navy

Conflict Usage

Side: 🏳️Unspecified

The Russian Navy fields seven Project 667BDRM Delfin (Delta IV) SSBNs in the Northern Fleet. Open sources confirm the class's active operational status, but they do not tie this entry to a single named modern conflict.

Timeline

Delta IV-class submarine Key Events

Jan 1, 1975
Delta IV development begins
FAS says work on the Project 667BDRM Delta IV began on 10 September 1975 at the Rubin Central Design Bureau for Marine Engineering.
Sources: 667BDRM DELTA IV
Jan 1, 1985
First boat enters service
FAS says the first Delta IV submarine was launched in January 1985 and introduced into the Northern Fleet in December 1985.
Sources: 667BDRM DELTA IV
Jan 1, 1992
Build run ends
FAS lists construction and outfit for the class as running from 1985 to 1992, marking the end of the seven-boat production run.
Sources: 667BDRM DELTA IV
Jan 1, 2024
NTI still counts seven boats
NTI's Russia submarine capabilities review still describes the Russian Navy as possessing seven Project 667BDRM Delfin (Delta IV) SSBNs in the Northern Fleet.
Sources: Russia Submarine Capabilities

Delta IV-class submarine Images

Delta IV-class submarine, Nuclear-powered ballistic missile submarine class, Naval Systems - view 1 — Source: Submarine Novomoskovsk, 2016 1.jpg

Delta IV-class submarine, Nuclear-powered ballistic missile submarine class, Naval Systems - view 2 — Source: Submarine Novomoskovsk, 2016 2.jpg

Delta IV-class submarine, Nuclear-powered ballistic missile submarine class, Naval Systems - view 3 — Source: Delta IV class SSBN.svg

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Sources

Russia Submarine CapabilitiesPublisher: Nuclear Threat Initiative | Note: Supports class background, fleet size, Northern Fleet basing, and the 167-meter / 22-knot profile. | Accessed: 2026-06-25 Russia Submarine Capabilities (fielding)Publisher: Nuclear Threat Initiative | Note: Supports Various Conflicts: fielded and operated by the Russian Navy as seven active Delta IV SSBNs in the Northern Fleet. | Accessed: 2026-06-25 667BDRM DELTA IVPublisher: Federation of American Scientists | Note: Supports the Delta IV class design bureau, shipyard context, production run, missile fit, propulsion, displacement, speed, crew, and service chronology. | Accessed: 2026-06-25 Submarine Delta IV class.jpgPublisher: Wikimedia Commons | Note: Supports image provenance and public-domain status for the primary class image. | Accessed: 2026-06-25 Submarine Novomoskovsk, 2016 1.jpgPublisher: Wikimedia Commons | Note: Supports image provenance and licensing context for a Delta IV-class gallery image. | Accessed: 2026-06-25 Submarine Novomoskovsk, 2016 2.jpgPublisher: Wikimedia Commons | Note: Supports image provenance and licensing context for a Delta IV-class gallery image. | Accessed: 2026-06-25 Delta IV class SSBN.svgPublisher: Wikimedia Commons | Note: Supports image provenance and public-domain status for the Delta IV silhouette diagram. | Accessed: 2026-06-25