(ask) problem with enemy's course and precisely fire torpedo with sonar

[lajulanian]

I had a problem with enemy's course and precisely fire torpedo with sonar.

step that I already done :
1. I enter the sonar room, find the bearing until the light is on.
2. send bearing to the TDC.
3. determine the target. if enemy, in below 4000 m, it point to the some range.
4. I send the range to the TDC.
5. Fist : I set mark 1 to the enemy's ship.

and I repeat the sep 1 -5. until I get fifth mark. but the result on the mark is get me confuse.to set the angle of bow (AOB)

is there any suggstion ?

Nb: I use sonar because is Night. dark...

Thanks... sory for the bad english

[DrBeast]

Check out this video tutorial (http://www.youtube.com/watch?v=wiS9uevzR6A), should give you plenty of insight into how to do a sonar attack. If it doesn't load, this video (http://www.youtube.com/watch?v=YYmQoe_LYEM) is also very useful.

[Daniel Prates]

Full-sonar firing is, anyway, a secondary form of targeting and is usually less precise than visual methods... note that you mention precision, but sonar-oriented measurements always have a large margin of error. Can't you really peak for just a few seconds to add a stadimeter reading or two? That will increase your accuraty greatly.

[lajulanian]

Full-sonar firing is, anyway, a secondary form of targeting and is usually less precise than visual methods... note that you mention precision, but sonar-oriented measurements always have a large margin of error. Can't you really peak for just a few seconds to add a stadimeter reading or two? That will increase your accuraty greatly.


take a peak ?? ok.. good advice.

thanks a lot..

[Rockin Robbins]

I'm making another video of the Dick O'Kane Sonar Only technique some time soon. I borrowed a microphone last night and it sounded like a 1940's AM radio: not acceptable. Really there is nothing at all to be gained with a stadimeter reading. Sonar gives much more accurate (capitalize that. It's many times better.) range information than the stadimeter.

Where you might actually want to take a peak is right when you fire to get a perfect shoot bearing. On bearings, the periscope is more accurate than sonar.

So: your most accurate instrument for range is sonar or radar.

Your most accurate instrument for bearing is radar or periscope.

[Daniel Prates]

Really there is nothing at all to be gained with a stadimeter reading. Sonar gives much more accurate (capitalize that. It's many times better.) range information than the stadimeter.

RR, that is understood, but you mean active sonar. By reading the fellow's procedure in the first post, I understood - incorrectly? - that he uses some sort of multi-reference calculation with passive sonar. I guess that if he was using multi-pinging, he would not have the problems mentioned.

There are also other things to consider, such as revealing your own position. I never - that of course is just my playing stile - use active sonar.

You must have some sort of visual, anyway, even if it just to identify the target. Wouldn't want a large liner on your conscience, would you? :03:

That could be an interesting discussion. How frequent you captains actually use active sonar, and in which occasions?

[Rockin Robbins]

You must have some sort of visual, anyway, even if it just to identify the target. Wouldn't want a large liner on your conscience, would you? :03:

That could be an interesting discussion. How frequent you captains actually use active sonar, and in which occasions?

Uh.... I was in the middle of the Japanese Ocean, detected a great swarm or warships on sonar, did three pings to track a large noisy target, fired three, hit with three and sank......the USS Essex.

That was the end of my longest career. Assuming the target has been identified, the scorecard looks like this. You've just pinged the target:

They--O Crap!!! Somebody just pinged us. There's an enemy out there somewhere.

Us--Target! Bearing 054! Range 3150 yards!

Now you tell me if you gain an advantage by pinging.

As a submariner you spend a lot of your time in fear for your life. Isn't it great to make the enemy fear for his?:D

[MKalafatas]

I nearly always use sonar without periscope or range info, once I've ID'd the target. Range is irrelevant if you fire from the beam (limited only by torpedo arming distance and max torpedo range). Ergo, I use only passive sonar. You need only know the target speed, course, and correct firing angle. (e.g., 7 knots translates to an 11-degree firing angle if you're perfectly on the beam, and use a 36-knot Mark X; 9 knots = 14-degree firing angle). When the sonar man calls out the bearing of the approaching target, and it reaches the firing angle, I shoot. Actually I generally shoot about 1 or 2 degrees in advance, depending on how large the target is and how many torpedo hits will destroy it.

If you wait the 8 seconds or so for the "torpedo in the water" call, that generally translates into about 2.5 or 3 degrees of target bearing, moving across your bow.

Using the stadimeter, my torpedo accuracy was around 50 percent. Using sonar only, it exceeds 75 percent.

One caveat: zig-zagging targets are very difficult to hit this way.

Edit: so it was YOU who sunk the Essex????? ;)

[Char]

I borrowed a microphone last night and it sounded like a 1940's AM radio:not acceptable

What do you mean not acceptable? as least it would sound Period Correct! :haha:

[Daniel Prates]

They--O Crap!!! Somebody just pinged us. There's an enemy out there somewhere.

Us--Target! Bearing 054! Range 3150 yards!

Now you tell me if you gain an advantage by pinging.



Yeah, again, this is a playing-style subject, but in this scenario, the next line for them could be "left full rudder, all ahead flank", and your torp would probably be a miss. Visual ID and ranging has the advantage of being able to lurk silently up until a torpedo impact.

We discussed this last year, but I dont remember the outcome: if you are in a ship, say, a freighter, can you hear a sub pinging you?

[MKalafatas]

RockinRobbins, thanks much for the link to the O'Kane method YouTube vids. I didn't know about the two clicks issue on the TDC.

[Rockin Robbins]

Yeah, again, this is a playing-style subject, but in this scenario, the next line for them could be "left full rudder, all ahead flank", and your torp would probably be a miss. Visual ID and ranging has the advantage of being able to lurk silently up until a torpedo impact.

We discussed this last year, but I dont remember the outcome: if you are in a ship, say, a freighter, can you hear a sub pinging you?
That's just it, the merchies had no listening gear at all. The warships, rather than turning to avoid, if anything, would turn to engage. But they can't tell the bearing from which the ping is coming.

Their logical reaction would be no apparent reaction at all as their sonar guys feverishly try to hear the sub and get some kind of bearing. THEN they would turn toward, but they would have done that anyway upon deciding that they had a solid sonar contact on a sub by passive sonar. They would turn toward and go active.

Since their reaction to a ping is the same as their reaction without a ping, the only difference is that you've definitely told them you're out there.

Therefore pinging (with warships) should be done with a lot of thought if you believe they don't even know you exist. At that point you have such a huge advantage you may wish to keep it that way and listen passively. Good periscope technique is also probably going to keep you totally unknown.

Pinging warships is a slam dunk when they already know you're out there and you're looking for an edge. You've told them what they already know and you've learned their exact location.

But with merchants it doesn't matter. They don't know you're pinging. That's historically accurate too.:salute:

[TorpX]

I nearly always use sonar without periscope or range info, once I've ID'd the target. Range is irrelevant if you fire from the beam (limited only by torpedo arming distance and max torpedo range). Ergo, I use only passive sonar. You need only know the target speed, course, and correct firing angle. ....

At the risk of coming off as onery, I feel I have to point out a few things here.

The "range is irrelevant" is often repeated, but is really misunderstood. It is true that you can compute the lead angle for a firing solution, knowing the speed, track angle and bearing, without knowing the range, but that does not mean the range is irrelevant. (Also, it has nothing to do with the sub being on the "beam". The range dropping out of the equation for the lead angle holds only for a zero-gyro angle solution, whatever the positions of target and sub.) The firing solution for a 4,000 yd. shot may have the same angles and speeds, as a solution for a 2,000 yd. shot, but they are not the same. A small error in the data that would get you hits at 2,000 yds., would likely produce misses at 4,000 yds.

The thing often glossed over is the question of how would you obtain the speed or course without knowing the range? Speed might be estimated by observing the bow wave or by 'seaman's eye', but this would require visual observation anyway. Timing by wire also requires visual observation. The only other way I can think of that would not require any range info, is to use propeller counts. I think in practice RL captains relied mainly on calculations of distance/time (i.e. plotting). Another thing is that it would be almost impossible to determine the target's course without either knowing the range at several points, or accurately observing the AoB. This brings you back to visual (or radar) observations again.

Only a very few "sonar-only" attacks were made by US submarines. As far as I know, none were successful.

[Daniel Prates]

But with merchants it doesn't matter. They don't know you're pinging. That's historically accurate too.:salute:

That's the info I was looking for! :up:

I know they dit not have "active intercept" tech, but lets especulate on this a little bit. When we (subs) are submerged, we can hear pings clearly. There is NO WAY a merchant crewmen could hear a ping as well? I'm not talking game-wise anymore, just exchanging ideas.

The sound travels best in water, sure, but the reason we hear a ping when submerged is that the sub is very silent, and we are surrounded all around by water. It would be my guess that, in a noisy ship, and with surface noices (wind, waves etc) interacting with all other sounds, the ping would have to be pretty damn strong for you to hear it...

[Daniel Prates]

At the risk of coming off as onery, I feel I have to point out a few things here.

The "range is irrelevant" is often repeated, but is really misunderstood. It is true that you can compute the lead angle for a firing solution, knowing the speed, track angle and bearing, without knowing the range, but that does not mean the range is irrelevant. (Also, it has nothing to do with the sub being on the "beam". The range dropping out of the equation for the lead angle holds only for a zero-gyro angle solution, whatever the positions of target and sub.) The firing solution for a 4,000 yd. shot may have the same angles and speeds, as a solution for a 2,000 yd. shot, but they are not the same. A small error in the data that would get you hits at 2,000 yds., would likely produce misses at 4,000 yds.

The thing often glossed over is the question of how would you obtain the speed or course without knowing the range? Speed might be estimated by observing the bow wave or by 'seaman's eye', but this would require visual observation anyway. Timing by wire also requires visual observation. The only other way I can think of that would not require any range info, is to use propeller counts. I think in practice RL captains relied mainly on calculations of distance/time (i.e. plotting). Another thing is that it would be almost impossible to determine the target's course without either knowing the range at several points, or accurately observing the AoB. This brings you back to visual (or radar) observations again.

Only a very few "sonar-only" attacks were made by US submarines. As far as I know, none were successful.




Ha! My point exactely.

Another key issue to consider is that you should always try to fire from as close as possible. All margins of error decrese as you near in (except for your personal safety margins, but that is another issue). If we are talking about a lonely merchant, it is fairly easy to lurk ahead of him and wait till he is less then 2000, maybr 1500 meters away. And in that situation, a couple of statimeter readings are all you need for a "good-enough" range (and speed!) estimate.

[MKalafatas]

At the risk of coming off as onery, I feel I have to point out a few things here.

The "range is irrelevant" is often repeated, but is really misunderstood. It is true that you can compute the lead angle for a firing solution, knowing the speed, track angle and bearing, without knowing the range, but that does not mean the range is irrelevant. (Also, it has nothing to do with the sub being on the "beam". The range dropping out of the equation for the lead angle holds only for a zero-gyro angle solution, whatever the positions of target and sub.) The firing solution for a 4,000 yd. shot may have the same angles and speeds, as a solution for a 2,000 yd. shot, but they are not the same. A small error in the data that would get you hits at 2,000 yds., would likely produce misses at 4,000 yds.

The thing often glossed over is the question of how would you obtain the speed or course without knowing the range? Speed might be estimated by observing the bow wave or by 'seaman's eye', but this would require visual observation anyway. Timing by wire also requires visual observation. The only other way I can think of that would not require any range info, is to use propeller counts. I think in practice RL captains relied mainly on calculations of distance/time (i.e. plotting). Another thing is that it would be almost impossible to determine the target's course without either knowing the range at several points, or accurately observing the AoB. This brings you back to visual (or radar) observations again.

Only a very few "sonar-only" attacks were made by US submarines. As far as I know, none were successful.



Good post. Thank you.

[Rockin Robbins]

The width of the sonar detection in the game is always the same. You can find the outside on both sides and figure out the perfect bearing every time as the detection range is exactly 10º wide.

In real life that detection range is wider and variable. That means that where our in-game sonar bearing is accurate to plus or minus 1º, you're talking three or five degrees in real life. That makes all the difference in targeting accuracy.

It's also interesting that even though the pre-war official attack method was sonar only, I've never seen a description of their procedure. I'd love to see how their procedures differed from WernerSobe's or my techniques. It would be fun to use their exact method.

[TorpX]

It's also interesting that even though the pre-war official attack method was sonar only, I've never seen a description of their procedure. I'd love to see how their procedures differed from WernerSobe's or my techniques. It would be fun to use their exact method.

I haven't seen one either.

I find it interesting that eventhough it was "accepted doctrine", very few sonar-only attacks were made. Apparently, most skippers ditched the idea right away. But like you say, it would be interesting to try and do that way.

[Rockin Robbins]

That's what is most interesting. We're to believe that sonar only was "accepted doctrine" based on what? If everyone was expected to do it, the instructions should be easy to find. After all the Submarine Torpedo Fire Control Manual (http://hnsa.org/doc/attack/index.htm) tells intricate details about every other known attack method, allowing us to perform them with great fidelity to the original submarines.

But there is not one word of information about attacking with sonar only. If it were a valid attack method that did not work, they would likely have included it for future reference and possible refinement into a technique that DID work. But instead we have not one word of reference to this "standard accepted doctrine" in a book whose purpose was to train sub officers in "standard accepted doctrine."

It seems VERY unlikely to me that a universal doctrine would escape all notice in the standard reference on submarine tactics. They would at least have mentioned and outlined the technique while explaining that visual firing methods have proved much superior.

So something doesn't add up here. There is a disconnect from what we have been told to the actual training materials of the time. It's probably useless after 60 years to speculate why this is the case.

[Daniel Prates]

Pure-sonar methods seem to be taking a hell of a beating... :hmmm:

[TorpX]

I agree that it is somewhat odd that we don't have anything written about how to conduct "sonar-only" attacks, but there is a good deal of technical data about WW II weapons and such, that is hard to find nowadays. When I refered to it being "accepted doctrine", I meant an accepted doctrine, not the accepted doctrine. Most of what we have read was written after 1941, and reflects thinking of what occured after war broke out. I know that the TDC (I don't know which model) had a 'sound bearing converter' to aid this type of attack. So, it would seem the idea had gained some currency.

Perhaps the biggest reason we don't read much about 'sonar-only' attacks, is that most of the popular books relate patrols where IJN task forces were humbled, and merchant convoys were sunk. There aren't so many about how this sub or that sub, skulking about at 200 ft., fired off their torpedos in the direction of screw noises and came up empty. Success tends to get more attention than failure.

[ColonelSandersLite]

That's just it, the merchies had no listening gear at all.


I don't know for sure how historically accurate it is, but some of the merchies *do* have listening gear (no active set that I've seen, though some might have that too).


I know for a fact that the akita maru and nippon maru both have a listening set in their 45 configuration in both stock and tmo. What I don't know, is if various ships get them at various years, or it stays constant through the whole war. I also don't know how common the sets are really. Since I play with contacts off, I have no way of knowing if they have a set unless they detect me, and I don't exactly keep notes on it. If you play with contacts on, you can actually click the contact on the map and see their various sensor radius-es for yourself.

[Daniel Prates]

I don't know for sure how historically accurate it is, but some of the merchies *do* have listening gear (no active set that I've seen, though some might have that too).


I know for a fact that the akita maru and nippon maru both have a listening set in their 45 configuration in both stock and tmo. What I don't know, is if various ships get them at various years, or it stays constant through the whole war. I also don't know how common the sets are really. Since I play with contacts off, I have no way of knowing if they have a set unless they detect me, and I don't exactly keep notes on it. If you play with contacts on, you can actually click the contact on the map and see their various sensor radius-es for yourself.


I too read somewhere here in the forum that some merchants did have listening gear. And the possibility of active sonar being naturally audible has not been ruled out entirely, so far.

[TorpX]

I don't know for sure how historically accurate it is, but some of the merchies *do* have listening gear (no active set that I've seen, though some might have that too).
.......


I've read this too somewhere. It always struck me as kind of odd. I mean what is a unarmed or poorly armed merchant supposed to do if they hear something? It is kind of like giving shipwrecked sailors goggles, so they can watch for sharks, as they swim for the nearest island. I somehow doubt many Japanese sailors were saved this way. :shifty:

[ColonelSandersLite]

I've read this too somewhere. It always struck me as kind of odd. I mean what is a unarmed or poorly armed merchant supposed to do if they hear something? It is kind of like giving shipwrecked sailors goggles, so they can watch for sharks, as they swim for the nearest island. I somehow doubt many Japanese sailors were saved this way. :shifty:





Squirel around like crazy I guess, while vectoring in the nearest asw assets. It's hard to torpedo something that is intent on not getting torpedoed, and a lot of merchies should be able to win a gun battle during the day at least. I can see how having more sets of ears listening around the perimeter of a convoy could be useful though too.


The single biggest thing it means for me is that I don't do more than a few knots when I'm within 5000 yards of an unalerted target. I also wont use active sonar to ping anything ever, though I do run passive sonar plots if I don't have/can't use radar for some reason.

I've gotten enough practice at that in the u-boats that I'm actually pretty good at it now. Or at least I used to be before I stopped playing these games for a while.

[tomoose]

I'm about halfway through Dick O'Kanes book on the war patrols of the USS Tang. While sonar gets them close he always used the periscope for the actual shot(s). "Bearing - Mark! Set! Fire!" The Bearing via the periscope is O'Kane putting the wire on the desired part of the ship (as RR has explained in his "Dick O'Kane" method).

He was not stingy with the torpedoes either with 3 of them being the usual procedure.

He is currently in the China Sea along with Sealion. It is fascinating to see how much the submarine depended on each crew station to perform well in order to get a ship. In particular the patience in getting into a favourable position prior to an actual attack.

This book has given me new appreciation for what's involved and a desire to echo it (pun intended) in my own gameplay.

[ColonelSandersLite]

He is currently in the China Sea along with Sealion.

Hmm... someone might want to let those guys know the war is over and they can come home :D

[Daniel Prates]

In particular the patience in getting into a favourable position prior to an actual attack.

Getting into a proper position is indeed 90% of the attack. At least I always think things through that way.

[TorpX]

I'm about halfway through Dick O'Kanes book on the war patrols of the USS Tang. While sonar gets them close he always used the periscope for the actual shot(s). "Bearing - Mark! Set! Fire!" The Bearing via the periscope is O'Kane putting the wire on the desired part of the ship (as RR has explained in his "Dick O'Kane" method).

He was not stingy with the torpedoes either with 3 of them being the usual procedure.


Yes, as I recall he often used 3 or 4. It is kind of funny; SH 3 U-boat players cry like hungry children if they have to use more than one. :DL

I think this is a big part of the reason we can sink tonnages that RL captains could not.