'Unclosed Hatches' Sunk a U.S. Navy Nuclear Submarine at Port

What You Need to Know: In 1969, the USS Guitarro (SSN-665), a Sturgeon-class nuclear-powered attack submarine, sank while docked at the San Francisco Bay Naval Shipyard. Nearing completion after almost four years of construction, the submarine was undergoing final preparations when miscommunication between two work teams led to uncontrolled flooding.

-Both teams were filling tanks to adjust the vessel's position without coordinating their actions, causing water to reach uncovered hatches.