USS Thresher

[Calilasseia]

I was wondering what 'Zilla's take on this incident is.

For those not having encountered this incident, USS Thresher was the lead ship in a new class of nuclear powered attack submarine, whose keel was laid in 1958. The submarine was launched in 1960, and from the moment it went into service, it had a reputation for being a troubled boat.

First, the hull was made of a new type of steel, codenamed HY-80, which at the time was something of an experimental material. Lessons learned the hard way with this material led to its eventual adoption as a standard construction material for US nuclear submarines, courtesy of a combination of high tensile strength and excellent corrosion resistance, but in the case of the USS Thresher, the steel in question was new to the shipbuilders at the Electric Boat Company in Groton, Connecticut, and some of the properties of that steel were still being precisely determined. This may have impacted upon the submarine's final fate.

Second, the boat experienced an incident when in dock, when the reactor was shut down, and diesel generators used to keep the boat's critical systems running. The generators failed, and the battery back up power was insufficient to restart the nuclear reactor. Temperatures inside the machinery spaces of the boat rose to 140°F due to failure of the air conditioning and cooling systems as a result of insufficient power being present, and the boat had to be evacuated, followed by a "jump start" from another submarine. Hardly conducive to the morale of the crew.

Finally, the boat was on exercise off Cape Cod, when the submarine ran into trouble. Despite having positive up-angle, full power from the reactors, and the issuing of an order to perform an emergency blow of the ballast tanks, the boat was lost with all hands. The boat was operating at "test depth" - 1,000 feet - and apparently, flooding occurred in the engineering spaces. The order to perform an emergency blow was itself unusual, as under normal circumstances, a nuclear submarine is angled upwards whilst under conditions of neutral buoyancy, taken to periscope depth, and the ballast tanks then filled with air for the final surfacing operation. Given the 'teardrop' shape of USS Thresher (a feature of all modern nuclear subs), blowing the ballast tanks at 1,000 feet could have resulted in an unstable hydrodynamic condition, and was usually avoided - the fact that this order was issued, suggests that something was seriously wrong aboard the USS Thresher during the exercise.

One of the legacies of the USS Thresher sinking was the implementation of what became known as the SUBSAFE programme - a detailed tracking of every component of a submarine that comes into contact with sea water, and strict conditions imposed upon service life and replacement of those components, in order to prevent another submarine loss.

I was wondering, whilst indulging a tangential diversion elsewhere, if 'Zilla had any inside track on this. Only I gather the incident remains somewhat controversial to this day.

[Gawdzilla Sama]

The Naval History and Heritage Command has some ("some" is a Britishism here) information on this, but I haven't looked into it myself*. I can find you some links there if you want to delve into it.




*because bubbleheads are fucking nuts

[Tyrannical]

Back in my teens, I could name every sunken sub with approximate depth that had live nuclear weapons on board.
Aaah, the dreaming of youth.

[Gawdzilla Sama]

Back in my teens, I could name every sunken sub with approximate depth that had live nuclear weapons on board.
Aaah, the dreaming of youth.

It's probably just a rumor that such things would be dealt with by a "seismic event" these days. Just a rumor. Nothing more than a rumor, certainly.