1.   The American officials said that the submarines were not carrying the kind of rescue equipment, like a submersible vehicle, that could have helped.

2.   The Navy has allowed submarines to carry some civilians on such exercises for public relations purposes.

3.   The submarines now carry long-range nuclear-tipped missiles.

4.   Navy spokesman Igor Dygalo said the Oscar-class submarine was not carrying nuclear weapons.

5.   The submarine was carrying a new type of torpedo with a liquid fuel system that some officers complained was unstable, according to some reports.

6.   The three submarines carry sub-Harpoon sea-to-sea missiles.