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0 pointsJumpCrisscross1y ago0 comments

> this method would be much quieter

Source? Cavitation on propellers is a major source of uncloaking. This sub sounds fast but traceable—perhaps more ideal for a weapon than a vehicle.

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Staple_Diet1y ago

The method described in the present article doesn't rely on rotating propellers that produce vibrations, thereby reducing one of the major sources of noise.

JumpCrisscrossOP1y ago

> method described in the present article doesn't rely on rotating propellers that produce vibrations, thereby reducing one of the major sources of noise

The main source of “hull vibration and noise” from propellers is cavitation [1]. Laser propulsion directly cavitates.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4549849/

Turing_Machine1y ago

It sounds like it's basically a gigantic cavitation noise generator, so yeah, I'm not imagining that it could possibly be quieter.

Today's submarines go to great lengths to avoid cavitation for just that reason.

Typically there's a velocity beyond which the vessel does not go if it wants to remain stealthy, as going faster than that drastically increases the cavitation noise.

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