Transposition, or: Ship Happens [Worm/Aoki Hagane no Arpeggio | Arpeggio of Blue Steel]

[Pyrotech51]

Active jamming will give an opponent your location to within a few feet. All they need are two directional receivers, a map, and a ruler. And that is assuming they don't just fire a HARM in your general direction and let it hunt you down. TL;DR for a prepared opponent, active jamming is just a big 'SHOOT ME!' sign.

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The only way active jamming might work is if you had a fleet with multiple vessels generating identical signals, as at that point you'd be unable to distinguish individual targets within the mass. You'd know where the fleet was, but if done correctly you'd struggle to isolate individual vessels within the overall noise generated.

Of course there's also the possibility that you just output enough energy to overload the receivers, but at that point you have a DEW not a jammer...

 

[Monitor]

Active jamming will give an opponent your location to within a few feet. All they need are two directional receivers, a map, and a ruler. And that is assuming they don't just fire a HARM in your general direction and let it hunt you down. TL;DR for a prepared opponent, active jamming is just a big 'SHOOT ME!' sign.

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Solution: drones that Jam the hell out of everything. And you need to consider scanning technology. If jamming means they know where you are to a few meters, it not jamming means they know your position to a few millimeters, it might actually be still worthwhile, especially if it is dirt cheap to do it. Also, assuming the enemy operates as a fleet and you do not, the disruptions for their tactical net alone might be worth it...

 

[Monitor]

Also, I reread my post. I said stealth, not jamming. Although jamming might be useful to, in certain circumstances...

 

[Kryslin]

With passive stealth, you want to angle the surfaces in such a way in that they reduce or eliminate the return RADAR signatures. The use of RAM is not being considered for a naval vessel because the stuff is finnicky at best, and toxic when it burns. The large flat portions of the superstructure will give a strong RADAR return. You're not going to be able to do much about an IR signature, and the acoustic nose from the engineering plant will be enough for a submarine to ID the ship.

Ideally, the ship should have no surfaces perpendicular to the water.

So, everything would need to be angled away from vertical. If you really wanted to give the ship yard fits, constant curvature hulls, where the angles of reflection are never directly back towards the transmitter.

Active jamming came into the discussion because that was the only way I could see the design functioning as a stealth battleship without bankrupting Japan.

 

[TheUnicorn]

Active jamming will give an opponent your location to within a few feet. All they need are two directional receivers, a map, and a ruler. And that is assuming they don't just fire a HARM in your general direction and let it hunt you down. TL;DR for a prepared opponent, active jamming is just a big 'SHOOT ME!' sign.

Click to shrink...

There are ways to address that, the simplest is with multiple jammers trading off the jamming.

 

[Monitor]

Active jamming came into the discussion because that was the only way I could see the design functioning as a stealth battleship without bankrupting Japan.

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First, it is obviously a concept for a futuristic Japan. We have no idea what capabilities they have. Second, I Think we talk about what Taylor could make her ship like. And she has very few limitations If she decides to go all out.
Third: concept, again. There are a lot of concepts out there that explore what is possible, regardless of how utterly cost ineffective it is. The USA Navy sometimes even decides to build those concepts...

 

[spikethehobbit]

The only way active jamming might work is if you had a fleet with multiple vessels generating identical signals, as at that point you'd be unable to distinguish individual targets within the mass. You'd know where the fleet was, but if done correctly you'd struggle to isolate individual vessels within the overall noise generated.

Of course there's also the possibility that you just output enough energy to overload the receivers, but at that point you have a DEW not a jammer...

Click to shrink...

Tight beam DEW to overload the receiver is how all modern jammers work, but they require you to know where the opponent is. That works fine against actives but finding a passive is a major challenge.

There are ways to address that, the simplest is with multiple jammers trading off the jamming.

Click to shrink...

That works against 80's era radar, but modern SDR based phased arrays track fast enough to pick out the individual transmitters.

With passive stealth, you want to angle the surfaces in such a way in that they reduce or eliminate the return RADAR signatures. The use of RAM is not being considered for a naval vessel because the stuff is finnicky at best, and toxic when it burns. The large flat portions of the superstructure will give a strong RADAR return. You're not going to be able to do much about an IR signature, and the acoustic nose from the engineering plant will be enough for a submarine to ID the ship.

Ideally, the ship should have no surfaces perpendicular to the water.

So, everything would need to be angled away from vertical. If you really wanted to give the ship yard fits, constant curvature hulls, where the angles of reflection are never directly back towards the transmitter.

Active jamming came into the discussion because that was the only way I could see the design functioning as a stealth battleship without bankrupting Japan.

Click to shrink...

Passive stealth was broken by the Russians sometime around 1998 by using low frequency radar. High frequency Doppler radar tracks turbulence caused by the wind going around the target. There is no counter against either of those techniques. The only way to stealth a boat today is to go deep and slow enough that satellites can't track the wake.

 

[Rajvik_wolfboy]

Passive stealth was broken by the Russians sometime around 1998 by using low frequency radar. High frequency Doppler radar tracks turbulence caused by the wind going around the target. There is no counter against either of those techniques. The only way to stealth a boat today is to go deep and slow enough that satellites can't track the wake.

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and thus why all this "Stealth" naval tech is nothing more than a boondoggle. They will see you unless you come from beneath the thermoplane slowly, and even then it's better to release the SEAL team underwater instead of on the surface.

 

[Delusionist]

Passive stealth was broken by the Russians sometime around 1998 by using low frequency radar. High frequency Doppler radar tracks turbulence caused by the wind going around the target. There is no counter against either of those techniques. The only way to stealth a boat today is to go deep and slow enough that satellites can't track the wake.

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This is probably true. If it wasn't, we wouldn't know because it would be kept secret in an attempt to prevent the new method from being defeated.

 

[SlickRCBD]

They're both intended to be modern looking gun-armed vessels while also still hearkening back to WWII designs, such as having more secondary guns (or lasers) than modern ships carry, or having the Harpoon launchers be on swivels to be like torpedo mounts.

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Actually, the launchers for Harpoons used on some of the older ships like the Belknap class or the Perry class did swivel as well. The Mk10 and Mk13.

 

[TheUnicorn]

That works against 80's era radar, but modern SDR based phased arrays track fast enough to pick out the individual transmitters.

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As I said, that is the simplest method, but the fact the enemy knows where you are isn't always important as long as they can't hit you, and the system is effective against HARM, at least as long as you are capable of actually jamming the enemy, which does become rather difficult with modern systems.