The USS Thresher Disaster

Boston Globe:

The morning of April 10, 1963, was expected to be another round of rigorous but routine sea trials for the pride of the nation’s sub fleet. But what happened would jolt the nation: the worst submarine disaster in US history; the loss of all 129 crew, officers, and civilians on board; and a stinging blow to the American military at the hair-trigger height of the Cold War.
As the 278-foot-long Thresher began its descent that morning, only six months after the Cuban Missile Crisis, the unthinkable happened.

A pipe burst, electrical circuits shorted, nuclear propulsion shut down, and sailors on the USS Skylark, a trailing Navy ship, received these words from below: “Exceeding test depth.”

They heard little else from the crew, and the Thresher plunged more than a mile to the bottom of the North Atlantic. The Skylark, however, did hear the submarine’s death rattle: ominous hissing and groaning that preceded a devastating implosion that killed everyone on board within seconds.
“It seems just like yesterday to me,” 86-year-old Barbara Currier said from the same home where two Navy officers told her of the Thresher’s fate.
To help ensure that day is not forgotten, a memorial service was held Saturday at Portsmouth High School to commemorate the sacrifice of Currier and the other men who died. Organizers said about 1,200 people attended, including 76 former Thresher crew members and relatives of the lost....
The sudden loss of the Thresher, a fast-attack submarine designed to find and sink its Soviet counterparts, stunned the Navy. But the tragedy led directly to a rigorous reexamination of US submarine safety that is credited with preventing similar accidents.
“The Navy had an introspection,” said Galeaz, a veteran of the submarine service. “Not only did they do an inquiry, but they changed everything: quality control, inspections — everything changed. And that’s literally because of these guys on the Thresher.”
The remains of the disintegrated Thresher were discovered in 1985 by oceanographer Robert Ballard, who received secret funding from the Navy to search for the submarine while traveling to his publicly announced goal, the wreck of the RMS Titanic, which he also found on the voyage.

That is one bit of history I didn't know about.  It is hard to imagine being in that sub and just waiting for the pressure to get great enough to crush the ship in and kill you.  Hearing all the creaks and groans of the ship and wondering if this is it.  That would be the longest few minutes ever.