[akiselev]

》 The author completely ignores China's increasingly sophisticated anti-submarine underwater listening network. Just how stealthy are our submarines in comparison to the detection capability of a potential adversary?

Our nuclear submarines would probably be easily tracked with their "listening network" (I don't know anything about it) but diesel-electric submarines, which seem to be making a resurgence although not with the pro-nuclear forces in the navy, are far quieter and harder to detect. Combine that with the sound matting being develop for next gen subs and/or titanium hulls like Russia used to make, and you've got a very formidable submarine capable of high speed travel which will be very hard to detect with passive or active sonar.

[kosmic_k]

Passive, maybe, but active? I'm skeptical that there's any submarine in the world which can avoid active sonar. Further more the difference between a nuclear and diesel electric submarine's noise level would likely quickly be overcome by the resulting low frequency noises produced by the propeller at high speeds.

For example the Russian Alfas class were so loud when they were going top speed that US listening posts across the atlantic could hear them.

[Xylakant]

> but diesel-electric submarines,

Even better are fuel-cell powered subs. Less range than nuclear subs, but still formidable

[DennisP]

Why are diesels quieter? It seems like the opposite would be the case.

[Nokinside]

Diesels are used only when the ship recharges batteries. When the sub is underwater, they can run very silently and be completely silent when they stop.

Nuclear subs generate noise and vibration from the steam turbines, pipes etc. that can't be completely eliminated.

[dctoedt]

> When the sub is underwater, they can run very silently and be completely silent when they stop.

True, but diesel boats normally run on the surface, and on diesel, because battery life is limited; they generally submerge only to run an attack or to escape an attacker (or briefly at dawn, in case there's an unpleasant surprise out there that wasn't picked up). That's why nuclear submarines were once referred to as the first true submarines, as opposed to mere submersibles.

[Nokinside]

Modern air independent propulsion equipped diesel electric submarines have underwater endurance for several weeks. Even if they sprint full speed non-stop they could stay submerged several days.

[DennisP]

Ahh, makes sense, thanks.