quote:

Originally posted by tacfoley:
Many moons ago I did a three-day transit from Greenock, Scotland, to Plymouth down in SW England in an Oberon Class d/e submarine - all of it either at snorkel depth or surface running - just awful.

When we were snorkelling, every time it hit a wave the flapper valve operated, and the big diesels took their air from the crew compartments instead...not funny.

And that boat was old when I was in it.

tac

Curious, describe what it is like when the flapper shuts and engines draw crew air

quote:

Originally posted by Rightwire:

quote:

Originally posted by tacfoley:
Many moons ago I did a three-day transit from Greenock, Scotland, to Plymouth down in SW England in an Oberon Class d/e submarine - all of it either at snorkel depth or surface running - just awful.

When we were snorkelling, every time it hit a wave the flapper valve operated, and the big diesels took their air from the crew compartments instead...not funny.

And that boat was old when I was in it.

tac

Curious, describe what it is like when the flapper shuts and engines draw crew air

I read online in one of the articles (it only happens on the older D/E submarines) the newer ones either throttle back the engines or shut them off when the flapper valve closes......but according to the article there is a ton of negative pressure and would even blow some people's ear drums on the early German ones according to the article.

quote:

Originally posted by Rightwire:

Curious, describe what it is like when the flapper shuts and engines draw crew air

Having read a bunch of WWII U-boat accounts, it was EXTREMELY uncomfortable. When a wave caused the flapper to shut (to prevent an uncontrolled inrush of water), the diesel engines would suck in the air inside the boat (a sealed steel tube). This would cause a number of unpleasant symptoms, such as short-term lack of breathable air and a tremendous pressure change. Some suffered ruptured ear drums. If the snorkel tube wasn't cleared immediately, the entire crew could suffocate. The inrushing water could also flood the engines (literally) and they would have to switch to electric power until such time they could clear the water from the engines and restart the diesels. . .

That was 75 years ago, and I would hope there are automatic systems on the new boats that would either prevent or at least mitigate these effects.

That assumes that such systems were actually functioning properly. It sounds as if the routine maintenance wasn't what it should be, at least on this boat.

Although a 1955 US Submarine video, this answers a lot of questions

http://www.cnn.com/2017/11/28/...submarine/index.html

The new timeline, according to Argentine navy spokesman Enrique Balbi:

November 15, 12:30 a.m.: The sub's captain calls his land-based commander by satellite phone, saying that seawater has entered the vessel's "snorkel," a tube that reaches the surface to refresh the vessel's air and recharge the batteries. He says the water caused a short-circuit in the battery system in the vessel's bow and the beginnings of a fire, or smoke. The smoke was put out and the short-circuited system was isolated.

The captain indicates that the battery- and diesel-powered sub would continue traveling with its stern batteries.

6 a.m.: The captain types the same message and relays it to base electronically, as is protocol following a phone conversation.

7:30 a.m.: The captain calls base again, this time to say that the vessel is traveling, submerged, as planned, without any personnel problems.

10:31 a.m.: A sound consistent with an explosion is detected in the ocean, near the sub's last known location.

quote:

Originally posted by jimmy123x:

quote:

Originally posted by Rightwire:

quote:

Originally posted by tacfoley:
Many moons ago I did a three-day transit from Greenock, Scotland, to Plymouth down in SW England in an Oberon Class d/e submarine - all of it either at snorkel depth or surface running - just awful.

When we were snorkelling, every time it hit a wave the flapper valve operated, and the big diesels took their air from the crew compartments instead...not funny.

And that boat was old when I was in it.

tac

Curious, describe what it is like when the flapper shuts and engines draw crew air

I read online in one of the articles (it only happens on the older D/E submarines) the newer ones either throttle back the engines or shut them off when the flapper valve closes......but according to the article there is a ton of negative pressure and would even blow some people's ear drums on the early German ones according to the article.

It was 'uncomfortable' for a few seconds. A couple of the ERMs had temporary hearing loss amounting to a couple of months of deafness.

tac

quote:

Originally posted by jimmy123x:

quote:

Originally posted by 0-0:
Media reported the batteries are lead acid and were sort of remanufactured instead of replaced, recently.

Former sailor said the sub should carry 35 not 44 crewmembers.



0-0

I have NEVER seen remanufactured batteries be worth a shit. Knowing this I would guess a battery grenaded or two.

I used to service and repair high amp deep cycle rechargeable batteries. One of major users of our batteries is the avation industry. If they were that bad, well, you know......

quote:

Originally posted by SgtGold:

quote:

Originally posted by jimmy123x:

quote:

Originally posted by 0-0:
Media reported the batteries are lead acid and were sort of remanufactured instead of replaced, recently.

Former sailor said the sub should carry 35 not 44 crewmembers.



0-0

I have NEVER seen remanufactured batteries be worth a shit. Knowing this I would guess a battery grenaded or two.

I used to service and repair high amp deep cycle rechargeable batteries. One of major users of our batteries is the avation industry. If they were that bad, well, you know......

It depends on what was bad before they were remanufactured. What is actually remanufactured in them. I've seen places simply dump the acid out of old batteries and put new acid and say they're remanufactured and still using the old plates that have sulfide all over them etc. When they were remanufactured did they simply reuse only the cases and replace everything inside etc. I don't think anyone will say remanufactured ones are ever as good as new ones.

My guess is the forward battery bank that already shorted either gassed off a ton of hydrogen and something (spark) set that off causing the explosion, or the battery bank itself exploded.

Replacing batteries $8 million
Fixing old batteries 6.1 million

We took the cheapest solution and probably that is why we are a sub and 44 sailors short today.

What seems cheaper will cost you more in the long run.

0-0

0-0 - Our hearts go out to you and your fellow countrymen and women today.

tac

0-0, I am also sorry for what has happened to your sailors, and for the sadness and suffering this has brought to their families and friends.

Just so tragic, 0-0. Having a submariner in the family (my uncle...ret.), my heart goes out to you, your countrymen, and the families of those lost. RIP, crew of the ARA San Juan.

0-0, my condolences to your nation and it's people at the loss of your brave a sailors.

The search for a missing Argentine submarine will continue but the rescue part of the plan has ended, a spokesman for the country's navy announced on Thursday.

Capt. Enrique Balbi said the mission "extended for more than twice what is estimated for a rescue."

The search for the ARA San Juan has lasted for 15 days since it first vanished on Nov. 15 with 44 crew members on board.


The submarine was sailing from the extreme southern port of Ushuaia to the coastal city of Mar del Plata, about 250 miles southeast of Buenos Aires. It was originally scheduled to arrive last Monday at a navy base there.

The navy said the submarine reported a battery failure before it disappeared but investigators had no specific details of the problem.

After tracing several unsuccessful leads, investigators confirmed last Thursday that an explosion occurred near the time and place where the sub vanished.

Rescue teams had decided to reinvestigate an area in the South Atlantic after officials said they determined a noise heard hours after the vessel went missing could help pinpoint its location.

Balbi said the "hydro-acoustic anomaly" originated about 30 miles from the submarine's last reported location on Nov. 15 in the South Atlantic before going off the grid.

Hopes for survivors had already dimmed because experts have said the crew only had enough oxygen to last up to 10 days if the sub remained intact under the sea.

More than a dozen countries were involved in the search for the missing sub, including the United States. Search teams combed an area of some 185,000 square miles, which is roughly the size of Spain.


http://www.foxnews.com/world/2...r-sub-continues.html

Prayers and condolences for the family and friends of those on eternal patrol.

BBC - A spokesman for the Argentine Navy has just announced that the search has been called off.

RIP, Sailors.

tac

Called Off....WTF ???

quote:

Originally posted by nhracecraft:
Called Off....WTF ???

The sub only had enough O2 for the men to survive up to 10 days, if it had just settled on the bottom and nothing else was wrong. But it's been over 15 days now-so the have determined that there in no longer any chance any of the men are alive.

quote:

Originally posted by nhracecraft:
Called Off....WTF ???

They are still searching for the sub, but it is no longer a rescue mission.

Terrible news O-O.