Boat 14 went back - it found lots of floating bodies. They pulled in 4 people.

About 50% of people going in the water would have died within 2 minutes from cold water shock, sudden drop in temperature will often cause sudden cardiac arrest. Its often why kids die when they fall into ice.

By about 15 minutes 90% were dead from hypothermia. By 30 minutes basically everyone who went into the water would have died.

I think one of the few survivors in the water was the master baker and they think it's because he got absolutely smashed on all the booze before the ship went down. That helped keep him calm, and vasodilated. Plus a lot of luck!

It also means Jack from the movie was likely doomed to die whatever happened. Once you got wet hypothermia would quickly set in.