Torvalus

I was having a argument with a friend who states diesel subs are quieter, I told him that was probably a fact 20 yrs ago, but with convection cooling and other measures the sound on a nuclear sub should be very minimal. We were talking about LA class attack subs and modern chinese diesels. Any info supporting my opinion and his is welcome, because I really want to know the truth! thanks

Francois

The answer is not that simple as a yes or a no.
It all depends on the platform, the systems and other environmental issues.
An SSK running on batteries is very quiet, at low speed or idle.
But modern western designs of nukes are very very quiet at low speed as they can shut off the pumps.

Beside this, the nukes are usually bigger, so they can bring bigger sensors, so they are often better equipped.

The rest of the equation is rather classified.
The radiated noise of a I-688 is something you will not find in public forums.

For the Yuan/Kilo versus I-688, you have to understand that the US and its allies have been monitoring chinese assets for the last decade at least. They really know what they are talking about.

At the light of many recent exercices, it shows that chinese designs are rather noisy, even to compare with the russian tech. And don't believe Robinson's things. Kilo are not that silent. Not even talking of the sensros here.

The game would be very different versus a 212/214 or a Scorpene.

sparten

I alwasy thought that Boomers were a lot quiter than ever SSKs. Ohios for example.

__________________
"Any relations in a social order will endure if there is infused into them some of that spirit of human sympathy, which qualifies life for immortality." ~ George William Russell

Francois

Boomers are rather silent boats.
Triomphant is the quieter today, but it is 20 years younger (design) then the Ohios.
But you can't compare them to SSKs. Different use of assets.
SSBNs are running deep and slowly in the big seas, going around and avoiding detection.
SSKs are rather better hiding in the littoral seas.

Now, I won't tell a boomer is more silent then a SSK.
It has endurance and the high sea to hide.

Wraith601

SSKs are extremely quiet on battery but when they snorkel or run their diesels they're much louder. They lack the anywhere near the endurance or speed of an SSN which makes them basically slightly mobile minefields in way. They can defend coastal waters but can't really do much else.

__________________
"We always have been, we are, and I hope that we always shall be, detested in France."
-Sir Arthur Wellesley

Francois

A nuke at low speed is not noiser then a SSK on batteries.
Anyway, you have sounds sources you can't avoid (air-con, air-cleaners, cold chambers, systems.. everything what).
You can shut them down, but it is for only a short time.

Francois

Ah and it depends of the platform. You can not compare a Scorpene and a Kilo for example.