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  #1  
Old 07-24-2007, 04:27 PM
essell essell is offline
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Do "Shooting Solutions" exist in the Navy ?

In the film "Down Periscope" they use the term Shooting solution when ready to fire on another submarine.

But a google search picks up little except in reference to the film.

I have trouble thinking that the film writers just made the term up so I have to wonder where they got it from.

Is it a rare or out dated term ?
Did they use it in the wrong context ?

Or is it pure fiction?
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  #2  
Old 07-24-2007, 04:31 PM
Bryan Ekers Bryan Ekers is online now
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The more common Navy term is "firing solution" and it's used pretty much as in the film.
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  #3  
Old 07-24-2007, 04:32 PM
Quartz Quartz is online now
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Are you sure the term you mean isn't firing solution?

Paging robby and casdave
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  #4  
Old 07-24-2007, 04:32 PM
Fear the Turtle Fear the Turtle is offline
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I've always heard the term "Firing Solution", and that coupled with submarine in Google yields 2770 hits. Not sure if modern subs would use/need this, but older WWII subs needed to calculate speeds/distances/angles (think I first saw the term in Silent Service PC Game).
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  #5  
Old 07-24-2007, 04:33 PM
Quartz Quartz is online now
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Bah, beaten to it!
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  #6  
Old 07-24-2007, 04:43 PM
Tripler Tripler is offline
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I once asked a very similar question!

Quite a few folks hopped in to answer my original question, and dispel my erroneous misconceptions (being in the Air Force, thinking like a fighter jock and all).

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There ya go.
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  #7  
Old 07-24-2007, 05:43 PM
Boyo Jim Boyo Jim is offline
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I believe the term will refer to anything that needs shooting, not just submarines. And not just used by submariners either. Every weapon needs a firing solution in some way shape or form to hit its target. A pistol might need to be within 10 feet and aimed very precisely to have a 50-50 chance of a hit. An ICBM might need to be launched from within 5,000 miles. It's also sometimes called a basket -- if the weapon is properly oriented within the parameters of the basket, it will likely hit. Guided weapons have bigger baskets.

Every weapon also has CEP (circular error probability) which measures the precision of the weapon. Well, maybe not all use this term -- I think rifles use the phrase minutes of angle to mean pretty much the same thing.
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  #8  
Old 07-24-2007, 06:21 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Fear the Turtle
I've always heard the term "Firing Solution", and that coupled with submarine in Google yields 2770 hits. Not sure if modern subs would use/need this, but older WWII subs needed to calculate speeds/distances/angles (think I first saw the term in Silent Service PC Game).
Yes, all American submarines use this terminology to this day. Its is still important for us to verify all aspects of the target prior to the shot.
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  #9  
Old 07-24-2007, 06:43 PM
essell essell is offline
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I love you guys. thanks.
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  #10  
Old 07-24-2007, 10:10 PM
Xema Xema is offline
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From my days in the Navy I seem to recall the term fire control solution. I note that Googling this produces large numbers of hits.
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  #11  
Old 07-25-2007, 12:09 AM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Xema
From my days in the Navy I seem to recall the term fire control solution. I note that Googling this produces large numbers of hits.
That term is used as well. A fire control solution is obtainable at any time so long as there is some type of track on a contact.
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  #12  
Old 07-25-2007, 11:20 AM
SenorBeef SenorBeef is offline
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Quote:
Originally Posted by Fear the Turtle
I've always heard the term "Firing Solution", and that coupled with submarine in Google yields 2770 hits. Not sure if modern subs would use/need this, but older WWII subs needed to calculate speeds/distances/angles (think I first saw the term in Silent Service PC Game).
Yes, torpedos need to know where to go and where to look before they start tracking on their own. A common tactic is not to use the torpedo's active internal guidance until the very last moment - torpedos can relatively silently travel slowly through water, guided by a wire connected to the launching ship, getting updated information that the launching ship is silently gathering so that the target may not be aware of the torpedo's presence until the very end.

The old WW2-style torpedo data computers that computer firing solutions are rather clever machines, check out http://en.wikipedia.org/wiki/Torpedo_Data_Computer if you're interested.
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  #13  
Old 07-25-2007, 11:55 AM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by SenorBeef
.....torpedos can relatively silently travel slowly through water......
"relatively silently" ? "Slowly" ? Those are to words I would never use to describe a torpedo.
Although they have gotten quieter over the years, they are far from quiet. As far as slow....the slowest speed is still FAR from slow.
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  #14  
Old 07-25-2007, 12:08 PM
Paul in Qatar Paul in Qatar is offline
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Probably a British v. American thing. The Royal Navy avoids the use of the word "fire" to mean anything but a fire. They prefer "shoot" to avoid confusion. I would bet a British screenwriter mucked up the USN lingo at some point along the line.
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  #15  
Old 07-25-2007, 12:44 PM
mlees mlees is offline
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Quote:
Originally Posted by d1a1s1
"relatively silently" ? "Slowly" ? Those are to words I would never use to describe a torpedo.
Although they have gotten quieter over the years, they are far from quiet. As far as slow....the slowest speed is still FAR from slow.
Compared to a missile or shell?
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  #16  
Old 07-25-2007, 01:32 PM
SenorBeef SenorBeef is offline
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Quote:
Originally Posted by d1a1s1
"relatively silently" ? "Slowly" ? Those are to words I would never use to describe a torpedo.
Although they have gotten quieter over the years, they are far from quiet. As far as slow....the slowest speed is still FAR from slow.
Do you have expertise on the subject, or are you just guessing?

It's my understanding that when the US ship is the aggressor, they will attempt to manuever the torpedo near the target without detection before speeding it up and activating its internal guidance. This gives the target less reaction time, and can also obscure the firing sub's location by attacking from an angle different than the one the attacking sub would be on.

So yes, it's my understanding that the torpedo moves out quietly (ideally undetectable) and slowly (a few knots) until the terminal guidance stages. Do you think they just fire them out at full speed right off the bat as standard procedure?
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  #17  
Old 07-25-2007, 02:18 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by SenorBeef
Do you have expertise on the subject, or are you just guessing?

It's my understanding that when the US ship is the aggressor, they will attempt to manuever the torpedo near the target without detection before speeding it up and activating its internal guidance. This gives the target less reaction time, and can also obscure the firing sub's location by attacking from an angle different than the one the attacking sub would be on.

So yes, it's my understanding that the torpedo moves out quietly (ideally undetectable) and slowly (a few knots) until the terminal guidance stages. Do you think they just fire them out at full speed right off the bat as standard procedure?
Yes, I have first hand experience in submarine approach and attack. Although I must admit the attack portion has only been simulated thank god.
The torpedos leave the tube at a very high rate of speed. Matter of fact there are interlocks preventing the activation of the torpedo, one of which is a g-force minimum. Granted the weapon does not leave at full speed but it does leave at a relatively high speed, relative to most things in ocean.
Your tactics are in the right place but your torpedo operations are off.
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  #18  
Old 07-25-2007, 02:38 PM
Tranquilis Tranquilis is offline
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Quote:
Originally Posted by d1a1s1
Granted the weapon does not leave at full speed but it does leave at a relatively high speed, relative to most things in ocean.
Your tactics are in the right place but your torpedo operations are off.
On top of which, impulsing a fish in one of the noisiest things I've ever heard a boat do. Mind you, most of that noise is internal, but it's not exactly a stealthy operation.



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  #19  
Old 07-25-2007, 03:03 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Tranquilis
On top of which, impulsing a fish in one of the noisiest things I've ever heard a boat do. Mind you, most of that noise is internal, but it's not exactly a stealthy operation.



Tranq
Qualified in Submarines
Thats exactly why it should be done with a lot of speed across the line of site as well as in the contacts baffles....if at all possible.
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  #20  
Old 07-25-2007, 03:56 PM
Cerowyn Cerowyn is offline
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Quote:
Originally Posted by d1a1s1
The torpedos leave the tube at a very high rate of speed. Matter of fact there are interlocks preventing the activation of the torpedo, one of which is a g-force minimum. Granted the weapon does not leave at full speed but it does leave at a relatively high speed, relative to most things in ocean.
Your tactics are in the right place but your torpedo operations are off.
I agree that SenorBeef's comment about "a few knots" suggest that he's misguided (ha, ha) about torpedoes, but much of what he says is true. Although a torpedo travels very quickly compared to almost anything else in the water, it's still slow enough that at range, even a ship has a chance to dodge it. Modern guidance systems obviously work against that, but we had established drills that involved changes in speed and heading whenever torpedoes were detected. Airborne ordinance travel at speeds that make maneuvering futile, reducing defense to active systems (such as the CIWS Phalanx). I suspect that SenorBeef was thinking of the relative difference in speed between torpedoes and anti-ship missiles.
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  #21  
Old 07-25-2007, 04:45 PM
Tranquilis Tranquilis is offline
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Quote:
Originally Posted by d1a1s1
Thats exactly why it should be done with a lot of speed across the line of site as well as in the contacts baffles....if at all possible.
Indeed. But you do what you have to, and if you have to choose between revealing yourself, or losing the shot... Well, let's just say that I'm glad the skipper gets paid to make that particular call.
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  #22  
Old 07-25-2007, 04:48 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Cerowyn
I agree that SenorBeef's comment about "a few knots" suggest that he's misguided (ha, ha) about torpedoes, but much of what he says is true. Although a torpedo travels very quickly compared to almost anything else in the water, it's still slow enough that at range, even a ship has a chance to dodge it. Modern guidance systems obviously work against that, but we had established drills that involved changes in speed and heading whenever torpedoes were detected. Airborne ordinance travel at speeds that make maneuvering futile, reducing defense to active systems (such as the CIWS Phalanx). I suspect that SenorBeef was thinking of the relative difference in speed between torpedoes and anti-ship missiles.
Those drills are a false sense of security if you're talking US Sub Launched torpedos. In a normal firing scenario you name one ship that can out maneuver an ADCAP.

Last edited by d1a1s1; 07-25-2007 at 04:53 PM..
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  #23  
Old 07-25-2007, 04:57 PM
Tranquilis Tranquilis is offline
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There are two kinds of ships in the world - Submarines, and targets.

Seriously, though, there are darn few vessels of any nature that can outmaneuver a modern torpedo. This is why decoys and stealthing systems were, and continue to be, developed. Sure, there are some spoofing manuevers, but those are acts of desperation, not reliable defenses; The require absolutely perfect timing and absolutely optimum conditions to work. Doens't mean you shouldn't practice doing them, but keep current on your swimming quals, anyway.
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  #24  
Old 07-25-2007, 04:57 PM
mlees mlees is offline
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Quote:
Originally Posted by d1a1s1
Those drills are a false sense of security if you're talking US Sub Launched torpedos. In a normal firing scenario you name one ship that can out maneuver an ADCAP.
Is that the wire guided torpedo? I don't know enough about torpedoes specifically to say that manuevering would help as much as decoys and stuff...

I was on the USS Ranger, and I watched an exercise were the ships company winched a decoy object over the fantail. I assume that this was a decoy that made "ship noises". It was a little larger than the size of a couch, teardrop shaped. Are these effective at all?
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  #25  
Old 07-25-2007, 04:59 PM
d1a1s1 d1a1s1 is offline
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Wow...we're way off topic!
So, Navy "shooting solutions"...no.
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  #26  
Old 07-25-2007, 05:04 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by mlees
Is that the wire guided torpedo? I don't know enough about torpedoes specifically to say that manuevering would help as much as decoys and stuff...

I was on the USS Ranger, and I watched an exercise were the ships company winched a decoy object over the fantail. I assume that this was a decoy that made "ship noises". It was a little larger than the size of a couch, teardrop shaped. Are these effective at all?
All US Sub Launched torpedos are wire guided.
I seriously doubt that was a torpedo decoy...maybe a dipping sonar?
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  #27  
Old 07-25-2007, 05:17 PM
Tranquilis Tranquilis is offline
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Quote:
Originally Posted by d1a1s1
I seriously doubt that was a torpedo decoy...maybe a dipping sonar?
Possibly it was an AN/SLQ-25 "nixie" towed decoy. or possibly a towed sonar, or if it was fairly recently, it might have been an SQL-25B, which is both decoy and towed array.
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  #28  
Old 07-25-2007, 05:33 PM
Cerowyn Cerowyn is offline
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Originally Posted by d1a1s1
Those drills are a false sense of security if you're talking US Sub Launched torpedos. In a normal firing scenario you name one ship that can out maneuver an ADCAP.
I don't think anyone had any illusions that in normal circumstances, a Mark 48 was gonna make a mess of our boat (let alone an ADCAP, which came out just as I was going reserve). Nonetheless, we a) didn't expect USN boats (or anyone else who mounts them) to be shooting at us, b) things can go wrong with even the most modern fish, and c) it's better than just sitting there waiting for the fish to poke a hole in your can.
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  #29  
Old 07-25-2007, 06:03 PM
Tranquilis Tranquilis is offline
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Nasty as an ADCAP is, there are worse out there, and they came from a nation that was decidedly at odds with yours (and mine). Some of those torpedoes (going back some years now) are simply fearsome.
Quote:
Originally Posted by Cerowyn
... it's better than just sitting there waiting for the fish to poke a hole in your can.
That's the best argument possible for doing the drills; doing something, anything is better than sitting on it and awaiting fate.
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  #30  
Old 07-25-2007, 06:29 PM
SenorBeef SenorBeef is offline
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Quote:
Originally Posted by d1a1s1
Yes, I have first hand experience in submarine approach and attack. Although I must admit the attack portion has only been simulated thank god.
The torpedos leave the tube at a very high rate of speed. Matter of fact there are interlocks preventing the activation of the torpedo, one of which is a g-force minimum. Granted the weapon does not leave at full speed but it does leave at a relatively high speed, relative to most things in ocean.
Your tactics are in the right place but your torpedo operations are off.
Sorry, I didn't mean to sound nearly as arrogant as I might've. I just couldn't tell from what you wrote if you were taking a guess, or if you had personal experience with torpedoes, so my question was genuine curiosity rather than arrogance.

I'm not an expert myself, I've just read a lot about submarine operations (fiction and non-fiction) years ago.

Quote:
Originally Posted by Cerowyn
I agree that SenorBeef's comment about "a few knots" suggest that he's misguided (ha, ha) about torpedoes, but much of what he says is true. Although a torpedo travels very quickly compared to almost anything else in the water, it's still slow enough that at range, even a ship has a chance to dodge it. Modern guidance systems obviously work against that, but we had established drills that involved changes in speed and heading whenever torpedoes were detected. Airborne ordinance travel at speeds that make maneuvering futile, reducing defense to active systems (such as the CIWS Phalanx). I suspect that SenorBeef was thinking of the relative difference in speed between torpedoes and anti-ship missiles.
No, I know that the MK 48 ADCAP tops out at over 50 knots. It's just my impression that the speed is variable and controlled by the sub, and standard procedure is not to launch the torpedo and immediately go to maximum speed. If a target was 5 miles out they might try running the torpedo in low speed mode for 4 of those miles, and then turn on the internal guidance and fire it up to top speed for the last part of the trip, giving the torpedo a reasonable chance of being undetected up until this point. Is that way off?
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  #31  
Old 07-25-2007, 07:12 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by SenorBeef
Sorry, I didn't mean to sound nearly as arrogant as I might've. I just couldn't tell from what you wrote if you were taking a guess, or if you had personal experience with torpedoes, so my question was genuine curiosity rather than arrogance.

I'm not an expert myself, I've just read a lot about submarine operations (fiction and non-fiction) years ago.
No offense taken at all SenorBeef. You would be amazed, or maybe you wouldnt, at how accurate some of those books can really be.



Quote:
Originally Posted by SenorBeef
No, I know that the MK 48 ADCAP tops out at over 50 knots. It's just my impression that the speed is variable and controlled by the sub, and standard procedure is not to launch the torpedo and immediately go to maximum speed. If a target was 5 miles out they might try running the torpedo in low speed mode for 4 of those miles, and then turn on the internal guidance and fire it up to top speed for the last part of the trip, giving the torpedo a reasonable chance of being undetected up until this point. Is that way off?
These weapons do indeed have multiple preset speeds, though they aren't variable. Also, there are many standard engagement practices when it comes to submarine warfare but the most important tactic a submarine commander has is non standard tactics....if that makes any sense. Submarine commanders have a tradition of non traditional tactics. So are you way off? Absolutely not. It was only your torpedo operations that were in question but most of that is technically classified so how could you know?
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  #32  
Old 07-25-2007, 07:13 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Cerowyn
I don't think anyone had any illusions that in normal circumstances, a Mark 48 was gonna make a mess of our boat (let alone an ADCAP, which came out just as I was going reserve). Nonetheless, we a) didn't expect USN boats (or anyone else who mounts them) to be shooting at us, b) things can go wrong with even the most modern fish, and c) it's better than just sitting there waiting for the fish to poke a hole in your can.
Good points. Plus, Im mixing my scenarios.
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  #33  
Old 07-25-2007, 07:18 PM
SenorBeef SenorBeef is offline
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Quote:
Originally Posted by d1a1s1
No offense taken at all SenorBeef. You would be amazed, or maybe you wouldnt, at how accurate some of those books can really be.





These weapons do indeed have multiple preset speeds, though they aren't variable. Also, there are many standard engagement practices when it comes to submarine warfare but the most important tactic a submarine commander has is non standard tactics....if that makes any sense. Submarine commanders have a tradition of non traditional tactics. So are you way off? Absolutely not. It was only your torpedo operations that were in question but most of that is technically classified so how could you know?
I'm a little confused as to how I can be partially wrong. If sneaking a torpedo a lot of the distance to a target is possible, either the torpedo has to run at slow speed, or it can run at medium to high speed a lot more quietly than I suspect. I know the Russian passive sonar isn't nearly as advanced as ours, but I'd imagine they'd hear a 20+ knot torpedo coming from miles away.
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  #34  
Old 07-25-2007, 07:47 PM
d1a1s1 d1a1s1 is offline
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Originally Posted by SenorBeef
I'm a little confused as to how I can be partially wrong. If sneaking a torpedo a lot of the distance to a target is possible, either the torpedo has to run at slow speed, or it can run at medium to high speed a lot more quietly than I suspect. I know the Russian passive sonar isn't nearly as advanced as ours, but I'd imagine they'd hear a 20+ knot torpedo coming from miles away.
OK..It all depends on your situation. If the conditions of the attack favor a more stealthy attack then precautions can be taken to MINIMIZE the amount of noise you are putting in the water. I wouldnt go so far as to say you can sneak a torpedo up on a submarine but you can make it so they dont counterdetect as quickly. So in that sense you are correct. Keep in mind the delay is a matter of minutes. Does that make more sense?
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  #35  
Old 07-25-2007, 08:31 PM
Boyo Jim Boyo Jim is offline
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Here is a description of the ADCAP Mk 48 torpedo, though I cannot speak to its accuracy. If it is correct, the torpedo is switchable between 2 speeds -- approx 40 knots and 55 knots. There is no information about whether that can be changed after launch.

My best guess is that the highest speed would be reserved for only those very fast ships or subs that would stand a chance of escape by a high-speed run directly away from a torpedo shot from a fairly long distance. I have read elsewhere that some subs can make 40 knots, and maybe a a few cruisers and destroyers get up to the mid to high 30s. So a low speed setting could result in the torp running out of juice during a long stern chase.

There are all kinds of circumstances when a targeted ship or sub might not hear a torp coming. If the target is traveling a relatively high speed -- maybe above 20 knots or so -- its sonar performance will be seriously deteriorated. Local storms may have he same effects, and other ships' engines in the area may mask the sounds. Also, there layers of water in the ocean caused by differences in temperature and/or salinity that can drastically change how sound travels through these layers, and weaken (or strengthen) sound traveling through their boundaries.

Most likely the biggest acoustical difference in a "stealthy" attack is the point at which the attacking submarine will cut loose the torpedo from direct control. Until that point, the attacking sub can provide guidance through its own passive sonar. Once the wire is cut, the torpedo's on-board sonar goes active and becomes something of an beacon for its own presence. I have heard conflicting stories about whether the torpedo can guide itself though passive means. I would tend to doubt it because its own sonar performace would deteriorate at high speed, just like any other ship.

Please note the I have no personal military or naval weapon experience. My knowledge, for what it's worth, is just odds and ends that I've collected by reading news stories and techno-thrillers for 40 years or so. I'm just a geeky weapons hobbyist.
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  #36  
Old 07-25-2007, 08:41 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Boyo Jim
Here is a description of the ADCAP Mk 48 torpedo, though I cannot speak to its accuracy. If it is correct, the torpedo is switchable between 2 speeds -- approx 40 knots and 55 knots. There is no information about whether that can be changed after launch.

My best guess is that the highest speed would be reserved for only those very fast ships or subs that would stand a chance of escape by a high-speed run directly away from a torpedo shot from a fairly long distance. I have read elsewhere that some subs can make 40 knots, and maybe a a few cruisers and destroyers get up to the mid to high 30s. So a low speed setting could result in the torp running out of juice during a long stern chase.

There are all kinds of circumstances when a targeted ship or sub might not hear a torp coming. If the target is traveling a relatively high speed -- maybe above 20 knots or so -- its sonar performance will be seriously deteriorated. Local storms may have he same effects, and other ships' engines in the area may mask the sounds. Also, there layers of water in the ocean caused by differences in temperature and/or salinity that can drastically change how sound travels through these layers, and weaken (or strengthen) sound traveling through their boundaries.

Most likely the biggest acoustical difference in a "stealthy" attack is the point at which the attacking submarine will cut loose the torpedo from direct control. Until that point, the attacking sub can provide guidance through its own passive sonar. Once the wire is cut, the torpedo's on-board sonar goes active and becomes something of an beacon for its own presence. I have heard conflicting stories about whether the torpedo can guide itself though passive means. I would tend to doubt it because its own sonar performace would deteriorate at high speed, just like any other ship.

Please note the I have no personal military or naval weapon experience. My knowledge, for what it's worth, is just odds and ends that I've collected by reading news stories and techno-thrillers for 40 years or so. I'm just a geeky weapons hobbyist.
Look...you have to realize that a lot of the capabilities of our weapons (and others for that matter) are classified. All I can say is that the information you gather from google will not be from the sources that have the facts. SO in light of this...
Paragraph1=wrong
Paragraph2=wrong
paragraph3=very very true
Paragraph4=wrong
and paragraph5= explains the problems inherent in paragraphs 1,2, and 4
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  #37  
Old 07-25-2007, 09:12 PM
Boyo Jim Boyo Jim is offline
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Quote:
Originally Posted by d1a1s1
Look...you have to realize that a lot of the capabilities of our weapons (and others for that matter) are classified. All I can say is that the information you gather from google will not be from the sources that have the facts. SO in light of this...
Paragraph1=wrong
Paragraph2=wrong
paragraph3=very very true
Paragraph4=wrong
and paragraph5= explains the problems inherent in paragraphs 1,2, and 4
Please explain what is incorrect, without of course revealing any classified information. I noted that I could not verify the data about the torpedo,
Why would a sub use the torpedo's highest speed against a 15 knot freighter? Are you simply saying that the ship speeds I quoted are wrong?
Are you saying that it is more likely that a torpedo would be set to a slower speed against a highly capable warship?
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  #38  
Old 07-26-2007, 02:24 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Boyo Jim
Please explain what is incorrect, without of course revealing any classified information. I noted that I could not verify the data about the torpedo,
Why would a sub use the torpedo's highest speed against a 15 knot freighter? Are you simply saying that the ship speeds I quoted are wrong?
Are you saying that it is more likely that a torpedo would be set to a slower speed against a highly capable warship?
The speeds of the torpedo arent necessarily changed to suit the target. Most are a component of the certain modes a torpedo goes through when its shot. They dont just run straight for the target in most cases. Like for example if the torpedo is in a search mode in will be running somewhat slower. Also, depending on what search mode its in, passive vs. active, the speeds will vary. These weapons are a lot more complicated than most people realize. Generally the torpedos are preset to perform a certain way and that way is almost totally autonomous. The wire is primarily used only in cases where the torpedo isnt wunning in the right direction but normally its on its own. The torpedo makes its own speed changes.
When you think about it...whats the point in running it slower when shooting a merchant?
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  #39  
Old 07-26-2007, 03:27 PM
Boyo Jim Boyo Jim is offline
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I would think the point of a slower speed setting would be a substantially increased range. What would the point of a slower speed setting be for ANY target?
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  #40  
Old 07-26-2007, 04:31 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by Boyo Jim
I would think the point of a slower speed setting would be a substantially increased range. What would the point of a slower speed setting be for ANY target?
There isnt any! Thats what Im trying to tell you!
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  #41  
Old 07-26-2007, 05:57 PM
SenorBeef SenorBeef is offline
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Quote:
Originally Posted by d1a1s1
There isnt any! Thats what Im trying to tell you!
The speed does affect the maximum range, but since it can do 20 nautical miles at top speed, that's not so much a concern.

From wikipedia:

Quote:
The official performance data may be a gross understatement, according to non-military sources that put the depth at deeper than 600 meters, the top speed between 60 to 75 knots (110 to 140 km/h), the range at top speed at more than 20 nautical miles (37 km), and the range at lower speeds at more than 30 nautical miles (56 km).
Is that right? 75 knots? Impressive.


The reasons I could see for having the torpedo run at a reduced speed would be increased effectiveness of acoustic sensors, greater manueverability (I'm guessing, I'm not familiar enough with hydrodynamics to know for sure), and increased stealth.
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  #42  
Old 07-26-2007, 07:13 PM
d1a1s1 d1a1s1 is offline
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Quote:
Originally Posted by SenorBeef
The speed does affect the maximum range, but since it can do 20 nautical miles at top speed, that's not so much a concern.

From wikipedia:



Is that right? 75 knots? Impressive.


The reasons I could see for having the torpedo run at a reduced speed would be increased effectiveness of acoustic sensors, greater manueverability (I'm guessing, I'm not familiar enough with hydrodynamics to know for sure), and increased stealth.
Cant confirm any of the operating characteristics of course but they are very quick! Yes, the lower speed is in fact used for certain search modes as I mentioned earlier. As much as everyone here wants it to be, it is NOT for "sneaking" up on the target. The torpedos have been getting quieter through advances in engineering.
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