Diesel engine may have sucked out submarine oxygen

Sydney Morning Herald ^ | May 5, 2003 | Indira Lakshmanan in Beijing

[Cincinatus' Wife]

The Chinese submarine accident in which 70 crew died may have been due to a malfunctioning diesel engine that sucked all the oxygen out of the hull, a Chinese Navy official says.

Investigators believe the crew died within two minutes, after submarine No.361 descended on a training mission two weeks ago. All the victims were found at their posts, and there were no signs of struggle, suggesting that death came upon the men quickly, the official said.

The accident occurred during a training mission on April 16, the official said, but was not discovered by the navy until 10 days later, when the submarine crew did not contact their base as expected. The crew had been instructed to maintain radio silence during training to practise concealing their location.

The Chinese military publicly attributed the tragedy to mechanical failure, giving no further explanation, but Western naval specialists familiar with diesel-powered submarines said the official's account was plausible.

The official said the submarine had charged its batteries from its diesel engine at the surface in preparation for descent. Diesel power is switched off in preparation for descent because diesel requires oxygen to burn, the specialists said.

In this case, mechanical failure is believed to have caused the diesel power to continue running, depriving the hull of its oxygen and suffocating the crew, the official said.

"That is very plausible, and I'm inclined to believe that's what happened," said retired admiral Lloyd Vasey, who served 36 years in the US Navy, 12 of them aboard diesel-powered submarines.

Mr Vasey said from Honolulu that "the first thing you do when you dive is you shut off the diesel because it sucks up a lot of air, switch to battery power and close the hatch. People don't forget to shut it down", he said of the diesel engine, which in Ming-class submarines is easily shut off.

Mechanical failure of the engine, air induction valve in the engine room, secondary air ducts, or a gasket were possible explanations, Mr Vasey said.

"But it's possible we may never know the cause."

The No.361 submarine was built in 1995, making it one of the newer of the Ming class that China produced from 1971 to 1996. Intended for patrols and coastal defence, it is copied from the decades-old Soviet Romeo class, which was based on a German U-boat produced in 1944.

The Ming class is considered obsolete by the Federation of American Scientists, but Mr Vasey said that he could see no reason for Beijing to retire its fleet of Ming-class submarines, now estimated at 13, because "accidents can happen to any subs".

The Ming class usually holds nine officers and 46 sailors, suggesting that other technicians or staff officers were aboard for this exercise.

The accident highlights vulnerability in China's ageing fleet of domestic and Russian submarines, estimated to number about 90.

Submarines are tactically useful for China, especially to enforce its claim on the island of Taiwan, because they are difficult to detect, and unseen submarines are a powerful deterrent to any enemy.

The Boston Globe

[txzman]

...it is copied from the decades-old Soviet Romeo class, which was based on a German U-boat produced in 1944.

Nothing like modern technology!

[stainlessbanner]

they are difficult to detect, and unseen submarines are a powerful deterrent to any enemy.

I think a diesel engine would be much louder than a nuclear powered ship.

[Fudd]

I doubt this is the REAL way these sailors died, however.

I work with a graduate student from mainland China. We were talking about rockets and I mentioned the 1995 (or 96) Long March rocket failure, where a rocket veered off course just after launch and killed a number of people when it slammed into a local village. He did not believe me at first, but after I showed him a few web pages, his question became, "how come I never heard about that?" (he was in China at that time).

He's a smart guy, but he just doesn't get it.

[NCC-1701]

Don't forget about the planned manned spaceflight late this year. Thier spacecraft is based upon the Russian Soyuz spacecraft in use since 1967 when Soyuz 1 flew. That crashed and killed Vladimir Komorav. Hope the Chinese have a good flight.

[ko_kyi]

From what I have read, they are only louder when moving. When idle the reactor makes a little more noise than just using battery power. I don't think you can shut a reactor completely off, but I bet some Freepers can elaborate.

[poindexter]

Maybe they were running submerged with a (faulty) snorkel and died of carbon monoxide poisoning. Insidious.

[Noumenon]

Hey, Brian -

Apply your analysis to the Three Gorges dam project, and you've got a recipe for a catastrophe of unprecedented proportions. When - and not if - that dam fails, it'll plunge China into an economic free fall.

[bmwcyle]

When you run on the battery underwater, they are more quiet then a nuke depending on who made it. When you run on the diesel underwater, it is noisy and you die.

[LibertarianInExile]

You won't die if your sub has a snorkel. Even some modern ones do, ya know. :)

[boris]

"Diesel engine may have sucked out submarine oxygen

Where was Monica?

--Boris

[bmwcyle]

No, but you suck the air out quick if the snorkel valve is closed. The Sweeds are using hydrogen peroxide with a sterling engine. The hydrogen peroxide produces oxygen to be vented into the ship. The Russians use a some trick on their produced Kilo to extend the underwater time. But the snorkeo has to be open to use.

[boris]

We all lived
In a diesel submarine
Diesel submarine,
Diesel submarine.

We all lived in a diesel submarine...

[Blueflag]

But a diesel running on a snorkel is advertising to every passive detection system "here I am" ... and then you die.

Diesel Electric boats, GOOD ones, are hard to detect acoustically, especially if they are smart about thermoclines and hover/drift.

But the MADs and the blue lasers can find them/their wakes; and if you're close enough, the right 'SONAR' techician can discern their quiet spot in the water from the ambient noise around them.

If they fire a weapon, they die soon thereafter. Three nations are really good at ASW. We are one of them.

[OrioleFan]

They probably ought to test the sub for SARS.

[Cincinatus' Wife]

It sounded a little fishy to me too. I don' have your knowledge but I would have expected them to have some sort of an alarm sound if their oxygen was going. After reading your post, I wonder what they're hiding.

[Robert A Cook PE]

Good observations.....

The pain is rapid and excrutiating when the snorkel slams shut while submerged for more than 10-15 seconds.

CO/CO2 poisoning maybe from a bad ventilation lineup?

That could kill the crew without the pain and agony of of a diesel engine (which acts as a positive displacement pump until it shuts off naturally form lack of air!) pumping the air out of the sub.

Chlorine or battery gasses would also kill the crew, but with nasty indications of burns and over a longer period of time.

...---...---

Ten days of no activity from a surfaced sub on a training mission in a small enclosed waterway and the Chinese didn't notice? Not reasonable, even if they are claiming "radio silence."

[Robert A Cook PE]

US sub design for diesels is to have the diesel suck air directly form the ventilation systems (fwd compartment/missile compt/engineroom or wherever) and burn it and exhaust the gasses overboard.

As you know, the US and German snorkels extend above the surface, and allow replacement air to get into the whole boat, which obviously replaces the internal air being sucked into the diesel and sent overboard. That way, if a fire happens, (or the atmosphere is contaminated with some chemical or foreign agent like a freon leak, torpedo fuel leak, or whatever agent) you suck the bad air out through the diesel from the affected compartment, and bring in replacement clean air from outside the hull.

So how could a Chinese sub, based on Russian copies of a German design get cross-contaminated? First guys on-board would be the only ones to know, because they are ones who found (and fixed) the valve lineups.

[Gamecock]

They're planning to fly men to the Moon

How well do diesel powered rockets work in space?

[j_tull]

Beat me to it. Surely someone would have noticed the 4" vaccuum being pulled because diesel is running with the head valve shut. I agree, this ain't what happened.

[Cincinatus' Wife]

Not too well. HA!