this post was submitted on 14 Aug 2023
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Showerthoughts

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A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The most popular seem to be lighthearted, clever little truths, hidden in daily life.

Here are some examples to inspire your own showerthoughts: 1

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Was just watching Jack Ryan Season 3 and seeing the display of force and their movements causes some interesting dissonance given what we know now.

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[–] DigitalTraveler42 1 points 1 year ago (1 children)

From your article:

Diesel Electric Submarines Diesel generator machinery can cause a great deal of noise. Diesel electrics are only quiet when operating in electric mode.

In fact, diesel boats must raise a snorkel to have intake fresh air for combustion when operating the diesel recharging the batteries and is then visible to the world.

u212a todaro class submarine pietro venuti U212A Todaro class submarine Pietro Venuti You cannot run silently with the diesels running and charging the electrics, you can only run silently in the electric-only mode, submerged. And because that’s off batteries, your submerged endurance is limited.

Diesel electric submarines only use diesel mode when travelling on surface, or snorkeling. However, there is the Stirling engine submarine, that can run its two propulsion systems totally submerged.

The works on making nuclear boats quieter

[–] [email protected] 2 points 1 year ago (1 children)

So you agree that diesel submarines can be quieter than nuclear subs when operating in electric mode, although their range is limited.

That's good.

I thought this was turning into one of those reddit level discussions, where people refuse to accept they were wrong, because they'd rather 'win' an argument by misrepresenting what the person they're debating actually said, than have a nuanced discussion

[–] DigitalTraveler42 2 points 1 year ago (1 children)

Bro I just copied and pasted a literal quote from your own article saying otherwise, you are your own Reddit moment rn.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

This is one of the things you quoted:

can only run silently in the electric-only mode, submerged. And because that’s off batteries, your submerged endurance is limited.

Also in the article:

So, unique to nukes, are a bunch of pumps, turbines, and reduction gears, which a diesel boat in battery mode doesn’t have at all.

Ie. a diesel sub is quiet in electric mode, potentially quieter than nuclear subs because in battery mode there aren't turbines or pumps whining away, even though that is for a limited time.

Another example:

Stirling engine is particularly well suited for a submarine because the engine is nearly silent and can use the surrounding sea water as a heat sink to increase efficiency. Submerged endurance is dependent on the amount of liquid oxygen stored on-board and is described as "weeks". The class is characterized by its low acoustic signatures, extreme shock resistance, and a competent combat system. .... The class has many features that enhance stealth, helping it to remain undetected. All shipboard machinery is isolated and mounted on rubber dampeners to reduce vibrations and noises; a hydrodynamic hull design reduces noise, infrared signature, and active sonar response. Its magnetic signature is counteracted by 27 independent electromagnets, short circuiting extremely low frequency (ELF) electrical fields. Various hull coatings reduce active sonar response, and the mast is coated with radar-absorbent material. Combined with the near-silent operation of the Stirling generator and slow-turning propeller to prevent cavitation, the boats are very difficult to detect under water, especially in their normal area of operations, the Baltic Sea

https://en.wikipedia.org/wiki/Gotland-class_submarine

The article goes on to say:

In 2005, HSwMS Gotland managed to snap several pictures of USS Ronald Reagan during a wargaming exercise in the Pacific Ocean, demonstrating that it was in a position to sink the aircraft carrier.[11] The exercise was conducted to evaluate the effectiveness of the US fleet against diesel-electric submarines, which some have noted as severely lacking.

TLDR: an advanced/modern diesel submarine is louder than a nuclear submarine in normal operation. Chugachugachugachuga. Then it goes into battery mode. It goes near silent, quieter than many nuclear submarines which still have turbines, pumps, etc. The diesel sub dissapears like a ghost. Torpedo away, too late.

And that's a relatively old sub. The French sub I mentioned is something like a decade newer, with newer and better batteries.