[Onkel Neal]

Articles I have been reading estimate the ocean depth ~230 feet, so if they were unable to surface perhaps they could attempt an emergency escape.

http://www.dailymail.co.uk/news/arti...ated-Navy.html

Unlike modern nuclear subs, the 34-year-old, diesel-powered vessel must come up for air every seven days to replenish the cabin’s oxygen supplies and allow its four engines to charge its batteries.

The submarine has emergency canisters that would provide an extra few days of oxygen and remove toxic carbon dioxide, but there is a possibility that it may not be functioning because the vessel is out of power.

Frank Owen, from the Submarine Institute of Australia, told news.com.au that the crew could well be waiting underwater for their chance to surface.
“We know it’s been really rough, so even though the Argentinian navy protocol is to surface, it makes no sense with 6-8m waves to be sitting on the surface,” he said.

“If I was in that situation, I would be sitting on the bottom and waiting, doing everything I could to slow down my metabolism and eke out the life support mechanisms, reduce oxygen use and CO2 creation.”

http://www.news.com.au/world/south-a...53b89db966fec3