: 50 years. USS Thresher.

04-09-13, 10:37 PM
As a 12 year Submariner and current maintainer and frequent rider on Submarines, I would like to make a brief post about the USS Thresher SSN 593. 50 years ago on April 10th at 0918 in the morning the the Thresher was lost with 129 sailors and civilans on board while concucting her sea trials after upkeep.

It hurts to think about the loss of life, but their sacrifice has made modern submarines safe for enveryone involved based off what was learned from their loss and has helped to keep this country free. May they all rest in peace.
SSN 593 (http://www.history.navy.mil/photos/sh-usn/usnsh-t/ssn593.htm)
Ships Roster (http://www.ussthresher.com/roster/)

04-09-13, 10:40 PM
A moment of silence is observed.

04-09-13, 10:55 PM
Thank you to all who currently and have served!!! Your and your families sacrifices are what makes this country great.....

Cadillac Kid03
04-09-13, 11:26 PM
A moment of silence is observed.I second this.


04-10-13, 01:36 AM
So sad a story....thanks for the reminder.:tearflag:

I guess the news outlets were busy today.:nono:

04-10-13, 10:20 AM
Gulf of Maine, out of Portsmouth Naval Shipyard refuel/overhaul. I lost a 1st cousin in THRESHER.

There is quite a bit of "Remember when .......?" on the retired submariner sites today.

The sinking initiated a huge "SUBSAFE" study that ultimately changed the entire emergency blow system for the main ballast tanks. Submarines maintain a staggering amount (volume) of air compressed to 4,500 psi in huge flasks in the ballast tanks outside the pressure hull. That air is constantly used for hundreds of internal functions, so it slowly bleeds into the boat - two large 4-stage compressors return that used air to the flasks for use again as well as to maintain a pretty steady atmospheric pressure in the boat. SUBSAFE changed the way that high pressure air is used to blow out seawater ballast in an emergency.

This is a picture of a fast attack boat breaking the surface after a test blow from 1/4 mile - 1,300 feet down - the propeller is at STOP - all that vertical velocity is generated by moving hundreds of tons of seawater out of the ballast tanks quickly. THRESHER could not do that during a relatively small internal piping failure, so she sank. (That's 6,800 tons of boat popping out of the water)

EDIT: We did a test blow once a quarter during sea trials. It - ahem - gets your adrenaline going. LS1Mike remembers - I was the senior Diving Officer (submerged ship control) in USS JAMES K POLK (SSBN 545 (G)) for 5 years. Did quite a few of those. Seawater pressure ??? Multiply 1,300 X .445 - that's the psi on every square inch of the hull at that depth.

04-10-13, 10:29 AM
I remember the name and recall hearing something about it, but not much more. Didn't pay much attention to the news at that time. Hard to believe it has been that long ago.

04-10-13, 11:21 AM
Burnett Shotwell ETSeaman was going to INS school at FAAWTC Dam Neck, Va. at the same time I was going to SAM missile school there. He was a very gifted kid and had his whole life ahead of him. A sad loss.