Was designed to destroy strategic targets at intercontinental ranges. Adopted for operation by the Navy in 1974. Accommodated on the 667B nuclear submarines in number of 12 missiles and on the 667BD submarines in number of 16 missiles.

High combat and operating characteristics of the missile along with minimum weight and dimensions were achieved due to adoption of fundamentally new layout and design solutions on the missile, propulsion systems, onboard control system, ship-borne control system and launcher, as well as due to automation of pre-launch procedures, launch and overall scheduled checks of all missiles aboard the submarine.

The main solutions:

• the missile has two tandem stages of the same diameter with load-carrying fuel tanks having double dividing bottoms;
• high-density layout of missile stages was achieved due to accommodation of the 1st and 2nd stage engines inside the propellant tanks, the upper bottom of the 2nd stage fuel tank was made in the shape of a cone where an “upside down” (relative to flight direction) warhead was accommodated;
• absence of interstage and intertank sections;
• use of an all-welded missile body with completely sealed engine components and tanks fueled and encapsulated at the manufacturing plant;
• use of azimuthal astro-correction of missile flight by navigation stars and the Sun;
• use of an on-board computer in the control system;
• arrangement of the instrumentation section in the missile nose to provide star sighting and the possibility of replacement of the instrumentation section and warhead without unloading the missile from the submarine launch tube;
• creation of a launcher with rubber-metallic shock absorbers mounted on the submarine launch tube walls that made them reusable and improved the operational capabilities of the complex;
• use of an independent submarine-borne computer in the submarine missile control system;
• launches of missiles from under-water and above-water positions.

The control system with azimuthal astro-correction had no native or foreign counterparts and was used on ballistic missiles for the first time in the world. Even at great errors made by the navigation system in submarine heading, the astro-correction provided high accuracy in the intercontinental range firing.

The 1st stage propulsion system includes main and a steering engines. Two steering chambers mounted by means of gimbals are used for control.

The 2nd stage propulsion system consists of a gimbaled single-chamber engine.

The missile stages are separated after destruction of the missile body by an extended circular explosive charge due to the pressurized gases energy.

Application of an independent computer in the submarine-borne missile control system, of on-board missile computers together with the astro-correction system, high-degree automation of pre-launch and launch operations, control of these operations from a single control panel ensured high combat readiness of the missile system, reduced the time of pre-launch operations and allowed salvo firing of all the submarine-borne missiles.

The missiles can be launched from an under-water position of the submarine at a seaway of up to 8, i.e. they can be fired practically in any weather.

A possibility to launch missiles from a surfaced submarine and the intercontinental range of firing allows to make launches directly from the submarine bases.