RIP USS Thresher

[Bilge_Rat]

yes waking up this thread after 14 years since new info has been coming out on what caused the loss of USS Thresher.

https://www.popularmechanics.com/mil...ied-documents/

Following a successful lawsuit by retired Capt. James Bryant, the U.S. Navy has been forced to release the entire 1700 pages report on the sinking which was still confidential.

The official version was that a burst water pipe at depth had caused uncontrollable flooding which lead to the loss of the sub.

An alternative theory had been put forward by Bruce Rule in 2013 which is detailed here:

http://www.designed4submariners.com/...rpion_Loss.pdf

Basically according to SOSUS data analysed by mr. Rule:

1. While cruising "deep", around 1300 feet, Thresher had a short circuit which caused the reactors to shut down.

2. Due to the pressure and design faults, the compressed air was unable to blow the MBT (basically ice built up which blocked the air so the MBTs remained full of water); and

3. the crew scrambled to restart the reactors, but the sub drifted down way past its crush depth before this could be done.

This was an interesting theory, but new info has been coming out which gives it more weight:

1. Bruce Rule was a SOSUS technician way back in 1963 and he had analysed the data at that time on which he based his report;

2. mr. Rule testifed on this at the inquiry on the loss, but a lot of pressure was put on him to change his testimony and on members of the inquiry to not adopt his theory as the official cause.

The inquiry reported that the Thresher’s MCPs had stopped, which would have caused an automatic reactor shutdown (scram) or a shift to slow speed. While Rule was positive the MCPs stopped, Naval Reactors said the acoustic data were inconclusive.6 Two commanders—not members of the Naval Court of Inquiry and likely acting as agents for Naval Reactors—tried to intimidate Rule during his classified testimony before the court into saying that the MCPs were in slow speed, not fast. Slow-speed MCPs were a more reliable lineup, but Ronald Estes, a reactor operator who served 14 months on the Thresher, recalls that it was normal to run fast-peed MCPs during deep dives to ensure immediate availability of flank speed to go shallow.

In a 1987 interview with Fred Korth, Secretary of the Navy when the Thresher was lost, and his executive assistant, Vice Admiral Marmaduke Bayne, both said Rickover had altered portions of the Naval Court of Inquiry’s report, and had probably done so because wording on MCPs was left as “inconclusive.”7 This deflected blame for the sinking away from Naval Reactors by creating doubt that there had been a scram.

https://www.usni.org/magazines/proce...-thresher-data

My own interpretation is that Adm. Rickover did not want any part of the loss to be blamed on the nuclear reactors which would have shaken confidence in their safety.