[Ikeon]

Traction drive. but they would be blind. 56kts, a lot of ocean covered in a short time. Imagine driving on the freeway in western Montana at night, without a moon or headlights. You may or may not hit someone or something.

[Pontiac]

Traction drive. but they would be blind.

Do you maybe mean ‘caterpillar drive’ or ‘magnetohydrodynamic drive’?

Caterpillar drive may be silent, but it isn’t fast. It could never get close to 50 kts.

I had thought about the issue of the sub being blind at that speed. But it is a drone and would be on a predetermined course. Cruising at depth on the predetermined route its only hazards would be whales and other subs.

In a war in which this weapon would be used it may be considered an acceptable risk.

And I am guessing that its speed is for purely defensive purposes; escaping a sub killer. Short sprints not long marathons.