#4 I used to write little quality presentations for weekly construction meetings, one of them was on the Thresher, (below). Sorry about the verbosity.
The Soviets were hard pressed to keep up with the Americans, so schedule pressures drove their ballistic missile submarine program. Roger Mudd said, in the History Channel program, that there are 17 nuclear submarines at the bottom of the ocean. Thirteen are Soviet. That’s 76%.
At least two submarine losses were American – the Thresher, in 1963 and the Scorpion, five years later. I’m old enough to remember both. The Thresher was the first of the Navy’s new attack subs – the fastest and quietest yet produced. Like the K-19, it had a problem with consistent and uniform welds. Submarine pressure hulls are 3-1/2” inches thick, and the welding of such thick metal requires precise procedures and precision work. The Thresher experienced some problems with welds on her shakedown cruise, so she returned to port for some weld repairs.
Not enough repairs, apparently. On the next dive of the Thresher, the Captain reported “a minor difficulty” from a maximum-depth dive. The Captain said he was about to “emergency blow”, which would rocket the sub to the surface and carry her halfway out of the water in white foam. But then the Thresher was silent, and moments later, sonar crews heard the hull of the Thresher crush. All 129 sailors and military and civilian technicians aboard were lost.
The subsequent investigation suggests the sub had another weld defect show up at the maximum depth, but the Captain was confident he could surface with the emergency blow procedure. Later tests discovered, however, that at that pressure, a filter in the emergency blow piping instantly froze over, rendering the procedure useless. The sub’s “Plan B” failed, and she lost depth control, and was crushed.
While the U.S. Navy had better quality control in the nuclear submarine program than the Soviets, one unforeseen condition that could have been discovered in a thorough testing program was a significant factor in the loss of the Thresher. Her loss at sea is often considered a watershed event in the implementation of the Navy’s rigorous submarine safety program called SUBSAFE.
That’s why many people do not like being on the ‘cutting edge’ of technology, and why State Agencies are so reluctant to change. Cutting edge technology is fraught with hidden disasters unless you have conducted a thorough test program to evaluate all “practical” potential operational conditions where a failure – or string of failures - might lead to catastrophe. So the “moral of the story” is to have some respect for the conventional means and methods, and approved plans and specifications of the contract. Approach the “cutting edge” with caution and respect.
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