passive detection range comparison between LWAMI and SC

[bishop]

Originally Posted by PeriscopeDepth

SC sonar model doesn't take into account speed of target. The only difference in signal level will be if the target is cavitating.

PD

If this is related to the speed/noise issue that was discussed back when DW was first released, I'm not sure this is true of SC. In the archive threads on this topic, Amizaur ran several tests on SC, both stock 1.08 and SCXII and concluded speed/noise modeling actually worked quite well. At the top of the thread he tested against SCX, then further down he tested again on Stock 1.08.

He concluded with "So I would say that the SC speed/noise relation was quite good and I would be absolutely happy if I had the same relation restored in DW :-)."

http://www.subsim.com/phpBB_archive1...r=asc&start=60

[PeriscopeDepth]

Originally Posted by TLAM Strike

Plus US sub captains didn't like the SUBROC since it genneraly required a ping to use effectivly.

Hmmm...I wonder why the precision of a ping was required? It was after all a rocket with a nuclear depth charge, no?

Bishop,
I guess I stand corrected. Reading that thread again was fun. Ah, back in the heady days of DW.

PD

[TLAM Strike]

Originally Posted by PeriscopeDepth

Hmmm...I wonder why the precision of a ping was required? It was after all a rocket with a nuclear depth charge, no?PD

Well when people think of nuclear blasts they think of huge city blasting explosions blasting wooden buildings to matchsticks.


But underwater its diffrent. The SUBROC only had a 5kt nuclear depth bomb, even for a tactical nuke that is tiny. Water helps to decrease the effects of the blast, the deeper the less effective the blast (which is why Russian subs were always being made to go deeper) and the blast is spread out over the entire hull of the sub rather than just one part as with a torpedo warhead or a depth charge so a sub is better able to survive a nuclear blast than a depth charge attack. Just to give you an idea how small a punch the SUBROC delivered here is a pic of a live test of a ASROC with a 10kt W44 warhead. Not that big of a blast (the ship is no more than 5 nm away.) Now imagin that much deeper at half the yeld, and you don't have a fancy BSY-1 fire control computer to help you do TMA (All OHP style DRTs). You miss judge the solution and you've got a really ticked off Russian sub out there possably with his own SUBROC getting ready to launch.

[MBot]

Originally Posted by TLAM Strike

[PIC of nuclear ASROC explosion]

I know nukes are bad, but this is such a phantastic photo. You even see the ASROC launcher of the destroyer still trained towards the explosion. I all their terribleness, nuclear explosions have some kind of weird beauty.

[goldorak]

Originally Posted by MBot

I know nukes are bad, but this is such a phantastic photo. You even see the ASROC launcher of the destroyer still trained towards the explosion. I all their terribleness, nuclear explosions have some kind of weird beauty.

You should have a peek at the book "100 suns" if you're looking for nice pictures of atomic explosions.

[Frame57]

Originally Posted by TLAM Strike

Well when people think of nuclear blasts they think of huge city blasting explosions blasting wooden buildings to matchsticks.


But underwater its diffrent. The SUBROC only had a 5kt nuclear depth bomb, even for a tactical nuke that is tiny. Water helps to decrease the effects of the blast, the deeper the less effective the blast (which is why Russian subs were always being made to go deeper) and the blast is spread out over the entire hull of the sub rather than just one part as with a torpedo warhead or a depth charge so a sub is better able to survive a nuclear blast than a depth charge attack. Just to give you an idea how small a punch the SUBROC delivered here is a pic of a live test of a ASROC with a 10kt W44 warhead. Not that big of a blast (the ship is no more than 5 nm away.) Now imagin that much deeper at half the yeld, and you don't have a fancy BSY-1 fire control computer to help you do TMA (All OHP style DRTs). You miss judge the solution and you've got a really ticked off Russian sub out there possably with his own SUBROC getting ready to launch.

I respectfully disagree on this point. Commodore Ward my ex CO spoke of this on occaison. Russian Subs were designed to go deeper to flee the MK-48. The threshold of a conventional torp is affected by water pressure. But a nuclear warhead it actually aids its intention and design. It dramatically increases water pressure. The goal is to implode the enemy with pressure produced by shock waves. Not to incinerate them.

[Castout]

Originally Posted by bishop

If this is related to the speed/noise issue that was discussed back when DW was first released, I'm not sure this is true of SC. In the archive threads on this topic, Amizaur ran several tests on SC, both stock 1.08 and SCXII and concluded speed/noise modeling actually worked quite well. At the top of the thread he tested against SCX, then further down he tested again on Stock 1.08.

He concluded with "So I would say that the SC speed/noise relation was quite good and I would be absolutely happy if I had the same relation restored in DW :-)."

http://www.subsim.com/phpBB_archive1...r=asc&start=60

That hurts ouch. I guess I've to spend more time with SC.

[TLAM Strike]

Originally Posted by Frame57

I respectfully disagree on this point. Commodore Ward my ex CO spoke of this on occaison. Russian Subs were designed to go deeper to flee the MK-48. The threshold of a conventional torp is affected by water pressure. But a nuclear warhead it actually aids its intention and design. It dramatically increases water pressure. The goal is to implode the enemy with pressure produced by shock waves. Not to incinerate them.

I just used that whole "Matchstick" thing as an example on how people think about nuclear weapons. I didn't mean to imply a SUBROC was ment to incinerate its target (at least when used against subs)

Well I think your CO got it backwards. Russian subs have always been designed to go deep, along with speed its the edge they have always had over our subs. The November had a 100 meter depth advantage over its American counterparts and the Russians have only gained on us in that area. The MK-48 was what was redesigned to compete with (the assumed) capablites of the Alfa. Of course the SUBROC predates the MK-48 so if Russian subs were being designed to defeat the current us ASW weapons of their era they were being designed to defeat the SUBROC and ASTOR both nuclear weapons, since the MK-37 could (unless fired from very close range or in the baffles) be simply out run.

I'm not totaly sure but it seems logical that increased water presure would have a negitive effect on the yeld of a nuclear weapon, simply from the explosive (kenetic) force having to push though more matter. Or maybe I'm thinking of thermal energy having to fight though pressure while kenetic energy would be aided by it. Do we have any phisics students out there? :hmm:

[Dr.Sid]

While the pressure of waters gets higher, density does not (or just a very little) because water can't be compressed (much). It is very different from gasses in this aspect.
Also both density and pressure actually makes the sound (or shockwave) travel faster and better.
I guess the pressure would add to the shock when it comes to overcoming stress limits.

[MBot]

Originally Posted by TLAM Strike

(the assumed) capablites of the Alfa.

Just a little interesting sidenote. It seems those assumtions where not that far off after all. I just read Rising Tide, where a former Alfa skipper talks about diving the boat to 3000ft.

[goldorak]

Originally Posted by MBot

Just a little interesting sidenote. It seems those assumtions where not that far off after all. I just read Rising Tide, where a former Alfa skipper talks about diving the boat to 3000ft.

Didn't the alfa have a hull of pure titanium ?
A very fine and costly piece of soviet engineering.
Why do american subs have to be so conservative. All the maverick designs came from the east. :p

[Castout]

Originally Posted by goldorak

Didn't the alfa have a hull of pure titanium ?
A very fine and costly piece of soviet engineering.
Why do american subs have to be so conservative. All the maverick designs came from the east. :p

And why did the Russians never put their titanium hulled submarine into full fledge production ? instead their backbone attack SSN were the Victors and now the Akula(Bars) class which is steeled hulled. I guess that tells us something....something prevented the Russians from putting its titanium hulled sub into full production imo.

The alfa I think I read it somewhere once went past right into a middle of NATO fleet exercise in high speed and deep depth. It was diving so deep that no weapon could touch it. It was very loud though so everyone could hear it. That was the event that sparked the development of the ADCAP I think. But I believe everyone here knows this story.

[SandyCaesar]

That story's new to me.

AFAIK, the Russian Sierras are the modern-day version of the Alfas, only much quieter and without the replaceable reactor core. No mass-production, once again.

But, going backwards, Alfas and Sierras can dive to that depth to evade attacks. Fine. I'm wondering, though, what they could do down there. 3000 feet sounds far deeper than what Russian torpedos can do, and while a titanium pressure hull can stand that, I'm not sure about an opened torpedo tube. So they could go super-deep for evasion, but for attacks they'd have to pop up to within the Mk48's envelope. Am I right?

[Frame57]

Originally Posted by SandyCaesar

That story's new to me.

AFAIK, the Russian Sierras are the modern-day version of the Alfas, only much quieter and without the replaceable reactor core. No mass-production, once again.

But, going backwards, Alfas and Sierras can dive to that depth to evade attacks. Fine. I'm wondering, though, what they could do down there. 3000 feet sounds far deeper than what Russian torpedos can do, and while a titanium pressure hull can stand that, I'm not sure about an opened torpedo tube. So they could go super-deep for evasion, but for attacks they'd have to pop up to within the Mk48's envelope. Am I right?

yep! You need to have enough air pressure to implulse the fish out of the tubes. they would have had to come to shallower depth..

[MBot]

I wonder what the tactical implications are from being able to dive into the deep sound channel. In my limited understanding of sonar this should give you a nice boost in detection range.

I guess deeper operating depth also give your sub generaly greater flexibility in utilizing layers.

Originally Posted by goldorak

Didn't the alfa have a hull of pure titanium ?

Yes, this made the Alfas (just as the Papa, Mike and the Sierra Class) immune to MAD detection from aircraft. And I guess also against magnetic proxy fuzes on torpedos.