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Escaping a sunk u-boat in shallow waters

I guess there is one advantage of being DC'd in shallow waters. Found the topic really interesting after reading about the USS Tang which was sunk by its own torpedo and 9 crew members managed to escape using the Momsen lung and escape trunk.

Quote:

There can be no doubt that U-boats dealt out death and suffering to many sailors, and many of their victims died under horrible circumstances from burns, wounds, exhaustion and drowning. By the same token, U-boat crews themselves suffered horrible deaths with many U-boats sunk with all hands on board. Many were trapped when their U-boat plunged out of control into the depths of the ocean and unable to rise again. The horrors of the pressure hull creaking and exploding under the pressure of the ocean depth is perhaps matched only by the grim situation of being trapped at the bottom of the ocean with the air supply running out. Many crews must have perished one by one as they lay trapped inside their boats.

During submarine school, U-boat crews were trained to deal with every combat situation. And that included the grim task of escaping from a sunken submarine. Underwater escapes were rare, although it is known that men often survived for lengthy periods in sunken U-boats.

Undergoing training with the Drager apparatus. The valve on his right breast is used to expel spent air, while the side valve controls airflow from the oxygen canister. Closeup of the Drager apparatus. The mouthpiece is clearly visible.
The escape equipment used for an underwater escape was primitive by today’s standards. Known as the Drager apparatus, it was a simple device which functioned as an artificial lung. It consisted of a tube attached to a face mask, an oxygen canister, a canister filled with carbon dioxide absorbent materials, a control valve and the entire apparatus was fitted inside a special vest, so it could be worn like a life jacket. To obtain air, the oxygen valve had to be opened, inhaled and then exhaled through a small vent in the face mask. Air was recycled so it functioned as a re-breather. There was a special valve which had to be manually opened to expel used air when carbon dioxide had accumulated to high levels. The Drager apparatus was meant to be used for underwater repairs and escapes up to 400 feet, although none had ever survived at that depth.

However it was impossible to open the escape hatch underwater, as the sea pressure pushing against the hatch would have jammed tight the hatch and the controls. The boat interior had to be flooded first by opening the flood valves. When the interior was fully flooded with sea water, thereby equalizing the interior and exterior pressure of the boat, then the hatch could be opened. Another hazard lies with the boat’s batteries. When exposed and mixed with sea water, it emitted a poisonous chlorine gas. Many U-boats were forced to the surface and abandoned when sea water seeped into the boat’s battery casings which had cracked under a depth charge attack.

One of the more remarkable escapes took place on January 21 1945. The U-1199 (Nollmann) had plunged to the bottom of the ocean, unable to surface. At 73 meters underwater, a petty officer managed to open the conning tower and reached the surface using his Drager apparatus. To this day, this harrowing escape remains as the deepest known operational escape from a submarine.

On October 3rd 1942, U-512 (Schultze) was attacked and sank to the bottom at 43 meters. When seawater reached the batteries, the crew collapsed after inhaling chlorine gas. But three managed to escape using the Drager apparatus. One survived.

October 16 1943 saw U-533 (Hennig) trapped at the bottom of the ocean after an attack by a RAF Bisley. Three crews managed to remain calm when the interior was flooded. They worked to open the hatch and reached the surface. In the event, one became unconscious on the way up and died shortly afterwards, the second died an hour later while the third survived. He drifted for 30 hours in the sea before reaching land. None of them had used an escape apparatus.

Another incident involved U-526 (Moglich). After an operational patrol, the U-526 was on its way back to Lorient when it struck a mine. Twelve men who happened to be on the upper deck survived, although nine were seriously wounded. But the U-boat sank to the shallow bottom with the rest of the crew. As it was in shallow waters, divers were sent down in a rescue operation. They managed to ascertain that there were survivors inside, but the hatch housing were so twisted due to the force of the explosion that they could not be opened. Everyone trapped inside perished.

Some escapes were more straightforward. On August 20 1944, U-413 had bottomed at the English Channel at approximately 27 meters. The Leading Engineer went forward to investigate the damage when an air bubble blew him out of the boat and safely onto the surface.

http://www.uboataces.com/articles-un...r-escape.shtml

I recall there was also an escape from a damaged U-boat before the war, in the Baltic. Can't remember the exact period for sure, though. The captain was a real stickler for regulations, which saved some of his crew. The U-boat was damaged in a collision with a surface vessel during a training exercise. The sub plunged to the seafloor due to catastrophic flooding, but the flooded comparment didn't kill everyone aboard because the Kaleun insisted on all internal hatches being shut at all times. The men in the damaged compartment died, but those in the rest of the sub were able to attempt an ascent. Some died escaping from the sub, but others lived who would otherwise have died had not the Kaleun been so insistent on closed hatchways.

In the game you could change a KIA career to surrendered via SH3 Commander if your circumstances were such that survival and surrender were viable. For example, in the game if you are forced to surface in the presence of ASW vessels in GWX you are a goner. The game does not have a surrender mechanism but you can honourably surrender your career and simulate the action of your crew abandoning ship and being picked up. It won't save your career but will allow a survivor tale in your personnel file.

Thanks for posting that story, U777.

I also remember reading about a US sub that wsa damaged and more or less sunk, but the crew swam up to another sub waiting.

But maybe that was a movie, as i know that happend in one movie, but im positive i read about the real even too.

That would be USS Squalus. The crew didn't swim to the surface, but were rescued by a team led by legendary underwater expert Charles 'Swede' Momsen.
http://www.history.navy.mil/faqs/faq99-1.htm

And the water in this case was pretty deep - about 75 meters.

On the other hand, when USS Tang accidentally torpedoed herself, some of the crew trapped below did manage to escape, using a breathing device also invented by Momsen. The depth that time was 180 feet - about 55 meters.

IRC there was also an escape from a sunken u-boat in ''44 or '45. The boat went down by a mine or by DD's (don't remember) and was flooding quickly. Only one guy came out alive by opening one of the torpedo tubes and swam to the surface.

U-64, Wilhelm Schulz's first boat, was sunk in the Norwegian fjords in 1940 and most of the crew made it out from the sunken boat. The survivors went on to become the core crew of U-124.

http://www.uboat.net/boats/u64.htm

Does anyone have a picture of what this "escape trunk" looks like?

THANKS

Quote:

Originally Posted by fastfed (Post 1487999)

Does anyone have a picture of what this "escape trunk" looks like?

THANKS

This is largely what it looked like, in a nutshell you get in, it floods then you can open the exterior hatch to get out, and then you close the hatch so the trunk can be drained and used for the next group of escapees.

http://t0.gstatic.com/images?q=tbn:j...0trunk.jpg&t=1

Escape trunk instructions from an old nuke sub but procedure should roughly be the same for the WWII versions.

http://www.heiszwolf.com/subs/albaco..._procedure.jpg