How do submarines navigate?

[Evadne]

/forums/images/graemlins/laugh.gif I like it. I think it stands for Phrench inertial nav. system. On some days, it even works. See http://www.ixsea.com/php/contenu/en/p-phins.php for a description and more acronyms than you can shake a stick at.

 

[bilbobaggins]

It seems that they *do* follow large merchant shipping about, hiding their own 'noise' in the very noisy wake of whatever they're following. As most of the world's large shipping is now 'scheduled', it's a bit like hitch-hiking.

Also, once the 'boomer' has got to its chosen patrol area, it will frequently seek a suitable underwater gully to lie up in, like a cougar in a cave. Position would be known accurate to a few feet, little need be done for 'station-keeping', and one's vulnerable 'back' would be covered by terrain-masking. Very little noise would be generated compared with motoring about, and residual noise transients are also largely screened from hunters.

There was a period when a certain chain of Norwegian fiords would have a Russian in that one, a Brit in that, an American, a French..... Hydrophone chains stopped that.

Nowadays, certain seamounts have their attractions. Especially those with nearby geo-thermal activity.

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