The Soviets viewed the Deltas as an iterative improvement of the Yankee-class submarines, which carried R-27 Zyb missiles with a range of 2,500–3,000 km (1,553–1,864 mi).

The earlier Delta boats remained in service until the 1990s, when the Soviet Union ceased to exist and many classes of submarines were decommissioned due to the severe budget cuts that resulted.

In the 1960s the Soviet Navy wanted new submarine-launched nuclear missiles that could threaten targets in North America without their launch platforms needing to pass the SOSUS sensors in the GIUK gap to be within range.

Consequently, unlike their predecessors, they no longer needed to pass through Western SOSUS sonar barriers to come within range of their targets.

The planform was largely the same, but the submarine was lengthened in the fourth and fifth compartments by 16 meters (52 ft) to allow the installation of four more missile tubes.

Unlike previous modifications, the Delta IV-class submarine is able to fire missiles in any direction from a constant course in a circular sector.

The underwater firing of the ballistic missiles can be conducted at a depth of 55 meters (180 ft) while cruising at a speed of 6–7 knots (11–13 km/h; 6.9–8.1 mph).

Unlike the Delta III-class design, it is compatible with all types of torpedoes, anti-submarine torpedo-missiles and anti-hydroacoustic devices.

The battle management system Omnibus-BDRM controls all combat activities, processing data and commanding the torpedo and missile-torpedo weapons.

[citation needed] The Delta IVs executed Operation Behemoth (Russian: Бегемот) during the twilight of the Soviet Union; they remain the only class of SSBN to successfully fire its entire payload of ballistic missiles.