The Typhoon-class easily dwarfs all other submarines. The mighty Ohio-class, the largest submarine ever built for United States Navy—nuclear powered and originally designed to conduct the United States’ nuclear deterrence patrols—is diminutive by comparison, only around a third the size of the mighty Typhoons.

Like the Ohio-class, the Soviet Union built the Typhoons to conduct nuclear deterrence patrols, lying quietly undetected in remote locations underwater and awaiting the command to launch their whopping twenty R-39 Rif intercontinental ballistic missiles at targets in the United States. The Soviet Union’s R-39 Rif missile was the largest intercontinental ballistic missile ever created, and the Typhoons were built around the missiles.

A quick look at their cross-section reveals just how massive the Soviet Union’s Typhoons are. Rather than sporting a more or less circular hull, the Typhoons were rather flatter, almost like a pinched oval. Inside the first pressure hull, two inner circular hulls were built around a central cluster of ten vertical launch cells. A smaller, third pressure hull was located in the middle, above the two main hulls, a design that increases crew survivability in the event of one hull being breached. So great is the available onboard space that there is supposed to be a sauna and small swimming area for each hull’s 160-odd crew members.

After the fall of the Soviet Union, there was concern in the United States and among North Atlantic Treaty Organization member countries that nuclear material—if not actual nuclear weapons—could fall into the hands of countries or groups that were less than friendly to the United States. Among those actors under concern were North Korea and Iran, or even terrorist groups. With partial help from the United States, Russia decommissioned a number of nuclear weapons and weapon delivery systems, including most of the Typhoons. Today, a lonely single Typhoon still exists from the Soviet glory days and serves as a test bed for newer Russian intercontinental ballistic missiles.

Interestingly, there was talk in the heady days immediately after the breakup of the Soviet Union of converting the Typhoons to cargo submarines rather than to scrap them outright. It was thought that the class’ large internal volume could be taken advantage of for transporting petroleum and gas products by sailing under sea ice and polar caps via routes that ships could not take. The project was ultimately abandoned however due to the complicated and expensive engineering obstacles that would need to be overcome in order to transfer oil from drilling platforms onto the submarines, and from the submarines to storage facilities.

Caleb Larson is a Defense Writer with The National Interest. He holds a Master of Public Policy and covers U.S. and Russian security, European defense issues, and German politics and culture.

Image: Reuters.