
Originally Posted by
Khathi
Optic cables are used in torpedo guidance in Russia since USET-80, IIRC. And I've heard that the problem with the towed spool started exactly because of it: traditionally, Russian torpedoes use a towed spool, because it allows for the full-auto loading of them into tubes, and buffeting in the wake didn't cause problems, as copper wire can tolerate much, much smaller bending radius. In fact, if you use something like a phone wire, that is, thin strips of foil or extra-thin wire wound around a thread and covered in insulation, you can sew and weave with it, without the wire breaking. Optic fiber, on the other hand, is much more sensitive to the bending and shaking, and tends to break much more easily. Thus, towed spools turned the wire guidance into a sort of luck-based mission: you fire the torpedo and pray that the wire doesn't break, because as soon as the wire breaks, torpedo either switches to wake homing (which is notoriously unreliable) or turns on the active sonar, and so long, stealth. UGST reportedly has a body-mounted spool, which exposes only the thin wire itself to the torpedo wake, and also uses a pumpjet, which makes it much less turbulent, so the chances of the wire not breaking is basycally the same as for Western torpedoes with their tube-mounted spools.