The Soviet Union built 6 Typhoon-class nuclear ballistic missile submarines during the Cold War. The Typhoon-class was the largest nuclear submarine ever built. Each measured 175 meters in length and displaced 48,000 tons submerged. Each carried 20 R-39 Sturgeon intercontinental ballistic missiles. The R-39 weighed 90 tons — twice the weight of the U.S. Trident II missile. Each R-39 carried up to 10 multiple independently targetable reentry vehi…