Quote:
Originally Posted by ET2SN
At one point during their construction, the Thresher and the Permit switched hulls. 
What happened to the Thresher will always remain a mystery, more than likely is that Thresher experienced flooding due to a bad weld or a defect somewhere in her piping which then shorted out a large chunk of her electrical systems which caused a SCRAM which caused a loss of propulsion. The icing effect was documented because they could reproduce the effect during the later investigation.
That investigation led to the SUBSAFE program which made the Navy and the builders bite the bullet and stop assuming things were fine because that was how they were done in the past. Radiography (X-Rays of weld joints and materials) and materials testing went from doing a sample when ever it "felt about right" to every piece of steel that would experience sea pressure and every weld that would hold them together.
As you mentioned, the emergency air system was redesigned and updated to the modern emergency main ballast tank blow system that featured hydraulic controls with a manual backup and much sturdier piping. 
The idea of running at flank bells at test depth probably came from Tom Clancy because the words sounded neat-o when he mashed them together.  No Navy is that crazy.  |
Except the Russians......
When we look at project 685 Plavnik (Mike class) she was a fastish submarine (No where near Alfa or Papa) 33 to 35 knots recorded depth to 1020 meters i do tend to wonder what the effects are on the hull's of titanium boats
We do know the Alfa had her max operational depth reduced, and like nearly most boats over time they get reduced.
HMS Ocelot originally used to dive down to 1000ft on for her to be reduced in later life to 750ft.
It must be like an aircraft so many cycles in its life.