One theory for the sinking of the Kursk is that a
torpedo exploded inside its launch tube.
I did not realise that highly concentrated
hydrogen peroxide can be used as a propellant. The Kursk was carrying torpedoes powered by it (which,
by the way, most other navies do not use because they do not consider it suffieciently safe).
The Russian navy webpages contain information about their hydrogen peroxide-propelled torpedoes at
http://www.militarism.navy.ru/torpedoes.htm
The whole affair is very sad, and the Russian people are understandably pissed at their leader, Vladimir Putin, and their Navy. The percieved problem being that Western help was not requested for many days after the event. Norway especially - who are very close to the accident - were frustrated that they had not been asked to help in the rescue sooner.