The crew of a submarine is trapped on the sea floor when it sinks. How can they be rescued before they run out of air? The crew of a submarine is trapped on the sea floor when it sinks. How can they be rescued before they run out of air? The crew of a submarine is trapped on the sea floor when it sinks. How can they be rescued before they run out of air? The crew of a submarine is trapped on the sea floor when it sinks. How can they be rescued before they run out of air?