This is coolbert:
The doomed Russian submarine Kursk did have integral escape mechanisms that COULD have allowed survivors to reach the surface.
* An escape capsule.
* Two escape hatches.
The former presumably some sort of pod allowing multiple number of sailors to ascend to the surface. NOT requiring flooding or pressurization of any sort? Persons inside the capsule are not exposed to the water during escape?
The latter, escape hatches, REQUIRING pressurization and exposure to the water during the ascent to the surface.
Sailors, those survivors left on board the Kursk, would don survival suits, place over their heads some sort of expedient breathing apparatus, flood the compartment connected to the escape hatch, open the hatch and flee the stricken sub in that manner.
Here is a photo of Russian submariners practicing "escape drill". Again, this sort of thing will not work in pelagic waters [deep]. Crush depth will be exceeded first, the hull of the sub breaking apart before the "sub bottoms out". Under such circumstance ESCAPE IS NOT POSSIBLE!
Those survival suits are quite impressive. Allow for flotation at the surface. Keeps the sailor warm for some time as well. The Russian Navy works almost exclusively in very cold waters [Barents/Baltic/Pacific]. Immersion normally means death from hypothermia in a few minutes. Under such conditions, a survival suit as worn by the Russian sailors IS A MUST!
Evidently a number of crew members on the Kursk did survive. Were trapped in a rear compartment for up to three days prior to death. They DID NOT ATTEMPT AN ESCAPE? Could have accessed an escape hatch? But did not?