Wire-guided torpedos[1] and missiles[2] are fairly common, and the wire pays out from the projectile-side so it's not progressively dragging more and more. The

Wire-guided torpedos[1] and missiles[2] are fairly common, and the wire pays out from the projectile-side so it's not progressively dragging more and more. The more recent DM2A4 Seehecht torpedo[3] has a fiber-optic link, probably to reduce EM emissions or the detectability of a km's-long wire/antenna, despite being underwater. [1]: https://en.wikipedia.org/wiki/Mark_48_torpedo https://en.wikipedia.org/wiki/Mark_48_torpedo [2]: https://en.wikipedia.org/wiki/Wire-guided_missile https://en.wikipedia.org/wiki/Wire-guided_missile [3]: https://en.wikipedia.org/wiki/DM2A4 https://en.wikipedia.org/wiki/DM2A4