S boat loses..pic heavy - Page 2

TorpX · 05-31-12, 11:20 PM

Quote:

Originally Posted by Armistead

Haha, wasn't a duel, it was an ambush in which I ran and got shot in the back.

Yeah, I was just kidding you there. Actually, considering the frightfull angle the sub was at, you did pretty well.

I had a VERY short career in SH 3 once.

I took my type II boat under for a test dive (the first).

I figured a German boat can go a lot deeper than US boats.

I figured there would be plenty of warnings before I reached crush depth.

I figured wrong.

RedTerex · 06-06-12, 06:09 AM

Quote:

Originally Posted by TorpX

Yeah, I was just kidding you there. Actually, considering the frightfull angle the sub was at, you did pretty well.

I had a VERY short career in SH 3 once.

I took my type II boat under for a test dive (the first).

I figured a German boat can go a lot deeper than US boats.

I figured there would be plenty of warnings before I reached crush depth.

I figured wrong.

Same thing happened for real to the USS Thresher on April 10th 1963 a new US Sub went out with full compliment of crew. It signalled that first dive was to commence and that was it!...was never seen or heard of again.

It is thought it went past test depth and just kept going, unable to stop, in water that was deep....very deep at over 8400 feet!

doulos05 · 06-06-12, 07:18 AM

Quote:

Originally Posted by RedTerex

Same thing happened for real to the USS Thresher on April 10th 1963 a new US Sub went out with full compliment of crew. It signalled that first dive was to commence and that was it!...was never seen or heard of again.

It is thought it went past test depth and just kept going, unable to stop, in water that was deep....very deep at over 8400 feet!

Well, there is some evidence to suggest there may have been a loss of propulsion due to maintenance failures on the nuclear reactor, but yes.

Undamaged Nuclear subs, unlike fleet boats, generally can't surface simply by blowing ballast, even an emergency blow of ballast. Propulsive power is basically a requirement for maintaining and changing depth in a nuclear submarine.

RedTerex · 06-07-12, 09:16 AM

Quote:

Originally Posted by doulos05

Well, there is some evidence to suggest there may have been a loss of propulsion due to maintenance failures on the nuclear reactor, but yes.

Undamaged Nuclear subs, unlike fleet boats, generally can't surface simply by blowing ballast, even an emergency blow of ballast. Propulsive power is basically a requirement for maintaining and changing depth in a nuclear submarine.

Thats very interesting, thanks for the heads-up. I would have thought that blowing ballast would have been enough to raise a sub of any description, what with all that air going in and expelling the "heavy" water out.

I suppose that with all the high tech stuff it corrupts the simplistic basics. Its gotta be like the engine of a 1970's car, lift the hood and we see...block, plugs, carb, basic wiring and thats it...just look under the hood today and you cant even see the engine through all the crap in there...so yep point taken.

twm47099 · 06-07-12, 07:54 PM

Back in the 1980's we had a visit from Capt Ed Beach (ret) at work. Besides serving in WWII subs and writing the RSRD series of books he had been the CO of the USS Triton when she made the first submerged voyage around the world. (The only time they surfaced was to have a sick crewman airlifted off.)

One of the topics he discussed during his talk was his impressions on the causes of the loss of USS Thresher.

Thresher was on its test dive after completing her Post Shakedown Availability when she was loss.

Based on what he knew of the subs and operating procedures of the time, along with the available voice and sonar recordings, he believed the following occurred.

Ship was negatively buoyant. But as she went deeper the negative bouyancy increased as the hull contracted. It appeared that was not adjusted as she went deeper. At test depth there was a report of a water leak. It was surmised that a sil-brazed seawater piping joint leaked and sprayed high pressure water on some electrical panel.

That scrammed the reactor, and they lost propulsion.

At that point they had to rely on battery power to either pump ballast to regain positive buoyancy or to restart the reactor. IIRRC they tried pumping because the time needed to regain propulsion would have exceeded the time they had before they would have reached collapse depth. However, at depth the pumping was too slow and rapidly depleted the battery.

There were sounds of high pressure air blowing (emergency ballast blow - EBB), but it cut off after only a couple of seconds. After a while the sound was heard again, but again it cut off quickly. Then contact was lost.

Capt. Beach believed that the EBB sounds were due to moisture in the air line freezing and plugging the line at the EBB valve. Back then the EBB valve was located outside the P hull and was surrounded by the cold seawater. High velocity air passing through the constrictions in the EBB valve would drop further in temperature and cause any moisture to freeze. He said they had experienced exactly that same situation (including the times) in Triton during an EBB drill.

After the loss of Thresher, the Navy made major changes to the design of many systems in the subs and instituted the SUBSAFE program to prevent each of those failure modes. One example is that high pressure seawater piping is welded, no longer sil-brazed. Also procedure now is to be positively bouyant on the test dive and use propulsion and dive planes to drive the ship to depth. That way loss of propulsion or plane control would allow the ship to surface w/o power.

Tom

doulos05 · 06-07-12, 09:34 PM

Now that is informative stuff there, I didn't know some of that, particularly the sil-brazing or the negative/positive buoyancy thing. I had heard the EBB part though, with the condensation freezing in the line.

TorpX · 06-07-12, 10:56 PM

Quote:

Originally Posted by twm47099

One of the topics he discussed during his talk was his impressions on the causes of the loss of USS Thresher.

...........
Tom

This is interesting info.

Char · 06-08-12, 02:03 PM

Great Story Armistead!

I had a Similar Situation in my own S-boat.but Instead of having that bad of a Down-Angle,I completly Rolled over and was UPSIDE DOWN.

I was never able to right myself,but I didnt die either!

When I hit the Surface key,I'd dive deeper.when I hit the Dive key,I'd Surface.When I broke the Surface,my Watch Crew came on deck..note that they were on deck Upside Down and Underwater....

I could only make about 10 Knots on the Surface,due to my props kinda being out of the water,but I made it back to Java.Ohh the looks on their faces when I pulled up to the Tender must've been PRICELESS.

Elektroniikka-Asentaja · 06-08-12, 03:37 PM

Quote:

Originally Posted by TorpX

So, you're saying that gun duels with Elite sub-killers isn't a good idea?

I understood that it was the opposite of this, heck, he sunk an enemy in a fair fight

I've had almost same angle with S-boat too, unluckily it was my front tubes that were removed from the ship so I was "ass in the air" there in less than 100 NM from Java and wondering how can I get back to port as I'll hurt my nose in the shallow..

Quote:

I just rammed Sumatra, nothing major.

Getting stranded is an art, I usually just hit the very small sand plants that don't show in map if not zoomed enough

06-07-12, 09:34 PM	#21
doulos05 Planesman Join Date: Sep 2008 Posts: 195 Downloads: 19 Uploads: 0	Now that is informative stuff there, I didn't know some of that, particularly the sil-brazing or the negative/positive buoyancy thing. I had heard the EBB part though, with the condensation freezing in the line. __________________ *While troubleshooting a printer at work Me: "Do you want me to run the copies through again?" Boss: "Hold on, let me go get the alcohol first. Me:

06-07-12, 07:54 PM	#20
twm47099 Bosun Join Date: Apr 2012 Posts: 67 Downloads: 93 Uploads: 0	Back in the 1980's we had a visit from Capt Ed Beach (ret) at work. Besides serving in WWII subs and writing the RSRD series of books he had been the CO of the USS Triton when she made the first submerged voyage around the world. (The only time they surfaced was to have a sick crewman airlifted off.) One of the topics he discussed during his talk was his impressions on the causes of the loss of USS Thresher. Thresher was on its test dive after completing her Post Shakedown Availability when she was loss. Based on what he knew of the subs and operating procedures of the time, along with the available voice and sonar recordings, he believed the following occurred. Ship was negatively buoyant. But as she went deeper the negative bouyancy increased as the hull contracted. It appeared that was not adjusted as she went deeper. At test depth there was a report of a water leak. It was surmised that a sil-brazed seawater piping joint leaked and sprayed high pressure water on some electrical panel. That scrammed the reactor, and they lost propulsion. At that point they had to rely on battery power to either pump ballast to regain positive buoyancy or to restart the reactor. IIRRC they tried pumping because the time needed to regain propulsion would have exceeded the time they had before they would have reached collapse depth. However, at depth the pumping was too slow and rapidly depleted the battery. There were sounds of high pressure air blowing (emergency ballast blow - EBB), but it cut off after only a couple of seconds. After a while the sound was heard again, but again it cut off quickly. Then contact was lost. Capt. Beach believed that the EBB sounds were due to moisture in the air line freezing and plugging the line at the EBB valve. Back then the EBB valve was located outside the P hull and was surrounded by the cold seawater. High velocity air passing through the constrictions in the EBB valve would drop further in temperature and cause any moisture to freeze. He said they had experienced exactly that same situation (including the times) in Triton during an EBB drill. After the loss of Thresher, the Navy made major changes to the design of many systems in the subs and instituted the SUBSAFE program to prevent each of those failure modes. One example is that high pressure seawater piping is welded, no longer sil-brazed. Also procedure now is to be positively bouyant on the test dive and use propulsion and dive planes to drive the ship to depth. That way loss of propulsion or plane control would allow the ship to surface w/o power. Tom

06-08-12, 02:03 PM	#23
Char Medic Join Date: Apr 2008 Location: Albany,NY Posts: 160 Downloads: 199 Uploads: 0	Great Story Armistead! I had a Similar Situation in my own S-boat.but Instead of having that bad of a Down-Angle,I completly Rolled over and was UPSIDE DOWN. I was never able to right myself,but I didnt die either! When I hit the Surface key,I'd dive deeper.when I hit the Dive key,I'd Surface.When I broke the Surface,my Watch Crew came on deck..note that they were on deck Upside Down and Underwater.... I could only make about 10 Knots on the Surface,due to my props kinda being out of the water,but I made it back to Java.Ohh the looks on their faces when I pulled up to the Tender must've been PRICELESS.