SSN was a Soviet nuclear-powered attack submarine (SSN) designed for high-speed, deep-diving operations. Built primarily from ...

CHALLENGER DEEP, MARIANA TRENCH, SOUTHEAST OF GUAM (WHTM) — The first dive to the deepest part of Earth’s oceans had its start with a record-breaking ascent into Earth’s atmosphere. On May ...

American diver breaks record with journey to the Mariana Trench 01:05. An American diver broke the record for deepest submarine dive ever and found something disheartening at the bottom of the ...

Clearly, then, there's a huge disparity between different types of submarines and just how deep they can dive, and the lack of official data and precise numbers only muddies the matter further.

What You Need to Know: Between 1968 and 1981, the Soviet Union built seven Project 705 Lira (NATO reporting name Alfa) nuclear-powered attack submarines. These cutting-edge vessels featured ...