Moving and Shooting

Biggen · 06-02-10, 02:23 PM

How does moving the boat and firing affect the accuracy of the eels? For example, from a dead stop (and my scope locked onto a target) I will determine the range, heading, speed, bearing, and AoB of a ship. I lock all of that in the TDC and then typically proceed on a course that is on a 45 degree angle to that ship if I am behind it (which I for some reason am ALWAYS behind and can never catch up). I figure the 45 degree angle helps with a low gyro angle, but this is all guesswork as I am still learning manual targeting...

However, when I have fired the last several times, I seem to be missing behind the ship. I don't know if this is because I have under estimated its speed or if it is because my forward speed is screwing with the TDC.

Does most everyone fire from a dead stop? How would the real U-Boat Captains done it?

TabbyHunter · 06-02-10, 02:37 PM

As i still use auto (god, deja vu from my early days of Navy Field...) and not manual, I cant help, but, i would assome real U-boot Kaleuns would fire from either a dead stop, driftig, or ahead 1/3rd at most.

Kpt. Weyprecht · 06-02-10, 02:45 PM

I'm not the greatest specialist here but I don't think it's because of your forward speed. Anyway, a good thing would be to get to a 90° position (or 45° forward of the ship) and to launch eels at 0° gyroangle so that the distance to the target doesn't matter anymore. I you may be experiencing that problem because the TDC doesn't update distance (while it does update the AOB), so if the gyroangle is not 0° and the distance matters, you have to shoot rapidly after the last distance update, otherwise the firing solution would get obsolete. So, if you manage to take the right position and launch your eels right ahead you will have more time.

Good hunting

Dissaray · 06-02-10, 02:54 PM

I have shot while on the go a number of times and have not observed any effect on my ability to hit the target. Likely what you are seeing is an error in your data gathering, likely speed or AOB. where movment is involved it is more likely speed that is throwing you off. If you are using a fixed line or other direct observation method of gauging speed movment on your part will throw you off every time, unless you are moving directly at or away from your target. If you are using a map charting method to figure target speed your movment will not effect the result in any way.

I use eather method depending on light and visibility conditions. When I can easyly see the target thru the various scopes I will use a fixed line method but in situations where I can't see the target or bad weather makes accuratly observing the target I fall back to the map charting method.

Biggen · 06-02-10, 03:09 PM

Quote:

Originally Posted by Kpt. Weyprecht

I'm not the greatest specialist here but I don't think it's because of your forward speed. Anyway, a good thing would be to get to a 90° position (or 45° forward of the ship) and to launch eels at 0° gyroangle so that the distance to the target doesn't matter anymore. I you may be experiencing that problem because the TDC doesn't update distance (while it does update the AOB), so if the gyroangle is not 0° and the distance matters, you have to shoot rapidly after the last distance update, otherwise the firing solution would get obsolete. So, if you manage to take the right position and launch your eels right ahead you will have more time.

Good hunting

You know, I never considered range to be the problem! That might just be it.

I'm going to try using Wazoo's Fast 90 method later today
http://www.paulwasserman.net/SHIII/#Section IV - Fast 90 Advanced Manual Targeting

Will range matter for this particular method?

frau kaleun · 06-02-10, 03:09 PM

I'm always moving when I fire, even if it's at the bare minimum speed necessary to maintain depth and/or maneuverability. Faster if I need to close the distance between myself and where the ship will be when I fire. I don't use manual targeting yet so if the speed of the u-boat makes a difference in the calculations, I have no idea. As I understand it the torpedo is like a mini-submarine, with its own propulsion and guidance systems - obviously when it's still in the tube it's traveling at the same speed as the u-boat surrounding it, but once it's fired I always assumed that it kind of does its own thing to achieve whatever speed it was set for, so whether I'm going 2 knots or 10 would be irrelevant. I could be wrong. It does seem like firing when the boat is not at 0 rudder with a constant heading makes a big difference, I've done that by accident a couple of times and oopsie I'll miss either fore or aft of the target depending on which way I was turning.

But my gut feeling is that a dead stop is a whole 'nother thing, because if you're not making enough speed to maintain control over your own heading then it seems like maybe that would make a difference. A "dead stop" in the water doesn't mean the boat isn't moving - you're in the water and the water is moving so your boat is moving right along with it. If you're not making enough speed to hold the boat on a particular heading, seems to me like you've lost control of one part of the equation.

I could be wrong about that as well, since I have absolutely zero practical experience with these things.

Ideally, you'd want to plot a ship's general course when you first make contact, and then plot a course of your own that will get you out ahead of where it will be by the time you are ready to close to attack range. This can take a lot of patience, and may mean not going after targets that it is impossible to outflank for one reason or another. But it is far more satisfying watching and waiting as a ship sails itself right into your clutches than it is trying to chase it down and having to settle for a shot at a less than optimum distance and/or angle.

Also if you are using impact fuses rather than magnetic, the torpedo needs to run as close as possible to perpendicular to the target's course to maximize the chance of detonation on impact. If it comes in at a less than optimal angle it may just skip off the side of the ship and never detonate.

pickinthebanjo · 06-02-10, 05:39 PM

I usually only fire while traveling 0-2 Knots as periscope would not take kindly to much more, but for surface attacks I usually match speed and course and have not noticed any accuracy problems yet

firefighter26 · 06-02-10, 05:56 PM

I like to predict the targets course and, usually, end up doing an 'end round' to get in front of it. This is easiest on the surface at night as I have more speed an my disposal. Ahead full, or even flank, for short bursts will often get me in front of the target, as long as they are not going to fast.

Once in position, in front, I will line myself up to perpendicular (90 degrees, facing his probably course). Then I will drop to periscope depth and wait. As the target gets close, he pretty much lines himself right up in front of me. I'll use head or back to put myself at an easy range.

I'll send the torpedo down its track before he hits 000 in front of me, so if it impacts and doesn't sink him, I have time to get off a second torpedo has he passes in front of me. Once the second is away, I'll hard over, ahead full to either pace him, or get back in front of him. If the second takes him out, it isn't a problem. If it doesn't, I am already on my way to the next firing position.

Sometimes I'll get fancy and cross in front of him, submerged of course, and fire a stern torpedo at his opposite side. If done right, as I get on the other side, and at the range I want, he should close to 180 to me, or directly behind me for the stern shot.

Dissaray · 06-02-10, 06:53 PM

Coming across their bow for the stern shot is a wonderful means to get your second or third shot in, just make sure to switch the AOB to the other side of the ship befor you fire if you are useing the TDC. I used that just today to finish the Hood. It has an added bonous of making it very hard for any escorts to falow you closely, if they try they will likely ram your target and it gives you lots of time to get deep and silent eather way.

Pisces · 06-03-10, 11:01 AM

Quote:

... I lock all of that in the TDC and then typically proceed on a course that is on a 45 degree angle to that ship if I am behind it...

After you make a course change, then the AOB setting is not valid anymore. If you turn onto a leading course (ahead of his bow), then the bearing he is shown at moves away from the bow since you want to keep looking at it. The AOB get's updated because of the bearing change when set to auto-update mode. You'll see that the AOB get's updated to a smaller number, but in the view it still has the same angle. (assuming the turn didn't take too long for him to get that much closer) Smaller AOB angle means also less leading angle by the torpedo due to the math-formula behind it. Hence it lags behind.

After every leading turn, and getting him back in view, you need to increase the AOB setting (away from the bow) by the same amount as the course change.

After every lagging turn (you turn to his tail side), and getting him back in view, the resulting AOB is bigger, and needs to be reduced (towards the bow) by the same amout as the course change.

If the turn was large enough for you to need to set the pointer beyond 180 degrees on the other side then do so.

Still, moving forward while doing the speed measurement can seriously affect the results. But I understood you did the measurements while stationary. Speed from stationary measurements are good. Just remember that you need to do a last range measurement as that one is not updated and definately different after a course change and some time passing until firing. However as said, with zero gyro angle range doesn't matter. (If the AOB setting is correct in the first place.

)

Apart from that, when you are allready behind him (AOB looks greater than 90 degrees) AND submerged then you'll never catch up with him. He's much faster on the surface than you are submerged. If you really need to stay in his front quarters, then put him on your 90/270 line, and keep it there constantly. That's the simplest way to come/keep ahead. But no garantuee of succes. He might still be too fast. Just continue until you are on the edge of visibility and then surface. Then with your much higher flank speed you should be able to get around him.

Biggen · 06-03-10, 02:53 PM

Quote:

Originally Posted by Pisces

After you make a course change, then the AOB setting is not valid anymore. If you turn onto a leading course (ahead of his bow), then the bearing he is shown at moves away from the bow since you want to keep looking at it. The AOB get's updated because of the bearing change when set to auto-update mode. You'll see that the AOB get's updated to a smaller number, but in the view it still has the same angle. (assuming the turn didn't take too long for him to get that much closer) Smaller AOB angle means also less leading angle by the torpedo due to the math-formula behind it. Hence it lags behind.

After every leading turn, and getting him back in view, you need to increase the AOB setting (away from the bow) by the same amount as the course change.

After every lagging turn (you turn to his tail side), and getting him back in view, the resulting AOB is bigger, and needs to be reduced (towards the bow) by the same amout as the course change.

If the turn was large enough for you to need to set the pointer beyond 180 degrees on the other side then do so.

Still, moving forward while doing the speed measurement can seriously affect the results. But I understood you did the measurements while stationary. Speed from stationary measurements are good. Just remember that you need to do a last range measurement as that one is not updated and definately different after a course change and some time passing until firing. However as said, with zero gyro angle range doesn't matter. (If the AOB setting is correct in the first place.

)

Apart from that, when you are allready behind him (AOB looks greater than 90 degrees) AND submerged then you'll never catch up with him. He's much faster on the surface than you are submerged. If you really need to stay in his front quarters, then put him on your 90/270 line, and keep it there constantly. That's the simplest way to come/keep ahead. But no garantuee of succes. He might still be too fast. Just continue until you are on the edge of visibility and then surface. Then with your much higher flank speed you should be able to get around him.

Wow, great information! It was probably me changing course AND an incorrect range that was throwing off my shots. I was thinking that AoB updates automatically, but it only updates automatically when turning the scope, NOT when turning the boat.

So as I understand it correctly, as long as the gyro angle is zero, range doesn't matter. Correct?

I always seem to be behind the target and trying to play catch-up for some reason. If this happens again, I'll try putting him on my 90/270, running out the edge, surfacing and then turning parallel to overtake him. That is a great idea.

I'm still trying to get a handle on AoB, but I must admit it I can never remember which way to turn the damn AoB dial when I figure out AoB. I typically have to look at my TDC map to determine if my shot will be behind or in front of the target. If it is behind, I know I turned the dial the wrong way.

As far as taking speed and heading of a target, I do do it from moving. Will this throw of my measurements as well? I use the 3:15 minute rule to determine speed. I like to use this instead of fixed line as I also get a rough approximation of the heading of the target when I make my second mark when 3:15 is up. This a bad idea?

Dissaray · 06-03-10, 04:37 PM

Just look at the red and green sections of the AOB dial, that is how I figure it out. The green is for when you are on the starbord, right, side of the target and the red is for when you are on the port, left, side of the target.

If you find your self behind a target and can't find your way around to the front without giving your self away or escorts make this problamatic you can still kill the target with ease. Though the accuracy of your data is paramount for this work. When you ID your target you can find the depth of the keel in your target recognition manual, the number is generaly diferant for every ship. Simply set your torpido's running depth to about 1m lower than the value given in the manual, so if the keel is at 6.5m set for between 7.5 and 8. Then make sure your torpido is set up with a magnetic pistol, by defult they all should be, and let fly with your shot, well swim but you get the idea. The torpido will cruse in right underneeth the target and blow up somewhere underneeth it. This causes herendous damage to your target and negates the need for a 90deg shot in most situations; though the 90deg is still your best bet for a good hit.

As for 90deg shots, range isn't all that important, as long as the target is inside around 1500m. The only time range realy matters is when your are realy close to bow on or stern on with your target, your extreem AOBs.

The speed measuring with the map, the 3:15 method, your speed dosen't effect your results. At least not as far as I can tell. It is beacouse you are measuring the target's movment relitive to the Earth and not the target's movment relitive to you; at least that is how I understand it to work.

Biggen · 06-03-10, 04:55 PM

Quote:

Originally Posted by Dissaray

The speed measuring with the map, the 3:15 method, your speed dosen't effect your results. At least not as far as I can tell. It is beacouse you are measuring the target's movment relitive to the Earth and not the target's movment relitive to you; at least that is how I understand it to work.

This is what I was thinking. But Wazoo has two different ways of getting a targets speed and heading. One is when your U-Boat is moving and one is without it moving. I'm just curious as to the difference. If I am marking its locations every 3:15 on the map, what does it matter if I am moving or not?? It's speed and heading shouldn't change if I am moving, right??

Damn computations...

Kpt. Weyprecht · 06-03-10, 05:22 PM

Quote:

Originally Posted by Biggen

I was thinking that AoB updates automatically, but it only updates automatically when turning the scope, NOT when turning the boat.

I should have been clearer. Sorry.

Quote:

Originally Posted by Biggen

So as I understand it correctly, as long as the gyro angle is zero, range doesn't matter. Correct?

That's it. The best way to achieve this is to calculate (plot) the target's course and to take the right position in advance. Then, you can either use a one of the lead angle tables, or use the TDC: you entre the data that you know by plottind. The scope/UZO must be pointing 0°, then you adjust the AOB to the value it will have when the target will be crossing the axe of your boat, i. e. at the moment of it's death. For a 90° shot, it will be 90°. Just avoid confusing boards... Then you can turn the auto-update back ON and turn the scope towards the coming target till the indicated gyroangle is 0°.

Quote:

Originally Posted by Biggen

I always seem to be behind the target and trying to play catch-up for some reason. If this happens again, I'll try putting him on my 90/270, running out the edge, surfacing and then turning parallel to overtake him. That is a great idea.

Getting to the right position seems to be actually the hardest part of it all.

Quote:

Originally Posted by Biggen

As far as taking speed and heading of a target, I do do it from moving. Will this throw of my measurements as well? I use the 3:15 minute rule to determine speed. I like to use this instead of fixed line as I also get a rough approximation of the heading of the target when I make my second mark when 3:15 is up. This a bad idea?

It isn't a bad idea and tactics-wise it's necessary. Remember than a real boat could never stay motionless, end they couldn't come to a dead stop submerged since they mould lose fine control of the depth. But I'm not sure if it is compatible with the 3.15 minutes rule.
Again, I strongly suggest using the mighty MoBo which allows you to do some relative plotting. Everything is fine as long as you move with a constant speed and course.

Your plotting may never be very precise (because of aur tools) if you take but two marks. Try some longer observations: I usually try to have at least three or four marks, taken with 5 minutes intervals rather than 3 minutes, and the target's vector is always calculated between the first and the last mark. This allows you to have a good solution in spite of errors in the measures since tese inaccuracies become statistically unimportant over a long distance.
Of course this requires you to stalk the target during some time and is most rewarding for night surface operations. But this is right: that's how most sinkings in early war were done.

Fette Beute!

sharkbit · 06-03-10, 06:10 PM

Quote:

Getting to the right position seems to be actually the hardest part of it all.

One of my favorite quotes, something I keep in mind in SH3/SH4, is from Edward L. Beach's "Run Silent, Run Deep":

Unfortuneately, I'm at work and don't have the book in front of me but basically it is.....

"Dammit Rich, anybody can shoot torpedoes and hit the target. The hard part is getting in front of the target to shoot." Or something like that.

(I'll have to find the exact quote when I get home tonight, but that is it in a nutshell.)

Except in desperation, a shot with much more than a 120 degree AOB is probably a waste of torpedoes unless you are at point blank range, and even then.....
I'll take the time to do another end around if I can to set up another shot where my chance of sucess is greater. If it takes 8 hours to do it, so be it.

Probably the greatest amount of time I spend in setting up an approach to a target is information gathering and getting ahead of the target.

06-02-10, 02:23 PM	#1
Biggen Watch Join Date: May 2010 Posts: 16 Downloads: 12 Uploads: 0	Moving and Shooting How does moving the boat and firing affect the accuracy of the eels? For example, from a dead stop (and my scope locked onto a target) I will determine the range, heading, speed, bearing, and AoB of a ship. I lock all of that in the TDC and then typically proceed on a course that is on a 45 degree angle to that ship if I am behind it (which I for some reason am ALWAYS behind and can never catch up). I figure the 45 degree angle helps with a low gyro angle, but this is all guesswork as I am still learning manual targeting... However, when I have fired the last several times, I seem to be missing behind the ship. I don't know if this is because I have under estimated its speed or if it is because my forward speed is screwing with the TDC. Does most everyone fire from a dead stop? How would the real U-Boat Captains done it?

06-02-10, 02:37 PM	#2
TabbyHunter Ensign Join Date: May 2010 Location: Pandora. Not the blue cat people Pandora... Posts: 227 Downloads: 52 Uploads: 0	As i still use auto (god, deja vu from my early days of Navy Field...) and not manual, I cant help, but, i would assome real U-boot Kaleuns would fire from either a dead stop, driftig, or ahead 1/3rd at most.

06-02-10, 02:45 PM	#3
Kpt. Weyprecht Gunner Join Date: Jun 2008 Location: Paris, France Posts: 97 Downloads: 89 Uploads: 0	I'm not the greatest specialist here but I don't think it's because of your forward speed. Anyway, a good thing would be to get to a 90° position (or 45° forward of the ship) and to launch eels at 0° gyroangle so that the distance to the target doesn't matter anymore. I you may be experiencing that problem because the TDC doesn't update distance (while it does update the AOB), so if the gyroangle is not 0° and the distance matters, you have to shoot rapidly after the last distance update, otherwise the firing solution would get obsolete. So, if you manage to take the right position and launch your eels right ahead you will have more time. Good hunting

06-02-10, 02:54 PM	#4
Dissaray 中国水兵 Join Date: Oct 2009 Posts: 280 Downloads: 35 Uploads: 0	I have shot while on the go a number of times and have not observed any effect on my ability to hit the target. Likely what you are seeing is an error in your data gathering, likely speed or AOB. where movment is involved it is more likely speed that is throwing you off. If you are using a fixed line or other direct observation method of gauging speed movment on your part will throw you off every time, unless you are moving directly at or away from your target. If you are using a map charting method to figure target speed your movment will not effect the result in any way. I use eather method depending on light and visibility conditions. When I can easyly see the target thru the various scopes I will use a fixed line method but in situations where I can't see the target or bad weather makes accuratly observing the target I fall back to the map charting method.

06-02-10, 03:09 PM	#6
frau kaleun Rear Admiral Join Date: Nov 2009 Location: Skyri--oh who are we kidding, I'm probably at Lowe's. Again. Posts: 12,706 Downloads: 168 Uploads: 0	I'm always moving when I fire, even if it's at the bare minimum speed necessary to maintain depth and/or maneuverability. Faster if I need to close the distance between myself and where the ship will be when I fire. I don't use manual targeting yet so if the speed of the u-boat makes a difference in the calculations, I have no idea. As I understand it the torpedo is like a mini-submarine, with its own propulsion and guidance systems - obviously when it's still in the tube it's traveling at the same speed as the u-boat surrounding it, but once it's fired I always assumed that it kind of does its own thing to achieve whatever speed it was set for, so whether I'm going 2 knots or 10 would be irrelevant. I could be wrong. It does seem like firing when the boat is not at 0 rudder with a constant heading makes a big difference, I've done that by accident a couple of times and oopsie I'll miss either fore or aft of the target depending on which way I was turning. But my gut feeling is that a dead stop is a whole 'nother thing, because if you're not making enough speed to maintain control over your own heading then it seems like maybe that would make a difference. A "dead stop" in the water doesn't mean the boat isn't moving - you're in the water and the water is moving so your boat is moving right along with it. If you're not making enough speed to hold the boat on a particular heading, seems to me like you've lost control of one part of the equation. I could be wrong about that as well, since I have absolutely zero practical experience with these things. Ideally, you'd want to plot a ship's general course when you first make contact, and then plot a course of your own that will get you out ahead of where it will be by the time you are ready to close to attack range. This can take a lot of patience, and may mean not going after targets that it is impossible to outflank for one reason or another. But it is far more satisfying watching and waiting as a ship sails itself right into your clutches than it is trying to chase it down and having to settle for a shot at a less than optimum distance and/or angle. Also if you are using impact fuses rather than magnetic, the torpedo needs to run as close as possible to perpendicular to the target's course to maximize the chance of detonation on impact. If it comes in at a less than optimal angle it may just skip off the side of the ship and never detonate.

06-02-10, 05:39 PM	#7
pickinthebanjo Seasoned Skipper Join Date: Mar 2010 Location: Canada Posts: 651 Downloads: 282 Uploads: 0	I usually only fire while traveling 0-2 Knots as periscope would not take kindly to much more, but for surface attacks I usually match speed and course and have not noticed any accuracy problems yet

06-02-10, 05:56 PM	#8
firefighter26 Watch Join Date: May 2010 Location: Vancouver Island, BC, Canada Posts: 17 Downloads: 2 Uploads: 0	I like to predict the targets course and, usually, end up doing an 'end round' to get in front of it. This is easiest on the surface at night as I have more speed an my disposal. Ahead full, or even flank, for short bursts will often get me in front of the target, as long as they are not going to fast. Once in position, in front, I will line myself up to perpendicular (90 degrees, facing his probably course). Then I will drop to periscope depth and wait. As the target gets close, he pretty much lines himself right up in front of me. I'll use head or back to put myself at an easy range. I'll send the torpedo down its track before he hits 000 in front of me, so if it impacts and doesn't sink him, I have time to get off a second torpedo has he passes in front of me. Once the second is away, I'll hard over, ahead full to either pace him, or get back in front of him. If the second takes him out, it isn't a problem. If it doesn't, I am already on my way to the next firing position. Sometimes I'll get fancy and cross in front of him, submerged of course, and fire a stern torpedo at his opposite side. If done right, as I get on the other side, and at the range I want, he should close to 180 to me, or directly behind me for the stern shot.

06-02-10, 06:53 PM	#9
Dissaray 中国水兵 Join Date: Oct 2009 Posts: 280 Downloads: 35 Uploads: 0	Coming across their bow for the stern shot is a wonderful means to get your second or third shot in, just make sure to switch the AOB to the other side of the ship befor you fire if you are useing the TDC. I used that just today to finish the Hood. It has an added bonous of making it very hard for any escorts to falow you closely, if they try they will likely ram your target and it gives you lots of time to get deep and silent eather way.

06-03-10, 04:37 PM	#12
Dissaray 中国水兵 Join Date: Oct 2009 Posts: 280 Downloads: 35 Uploads: 0	Just look at the red and green sections of the AOB dial, that is how I figure it out. The green is for when you are on the starbord, right, side of the target and the red is for when you are on the port, left, side of the target. If you find your self behind a target and can't find your way around to the front without giving your self away or escorts make this problamatic you can still kill the target with ease. Though the accuracy of your data is paramount for this work. When you ID your target you can find the depth of the keel in your target recognition manual, the number is generaly diferant for every ship. Simply set your torpido's running depth to about 1m lower than the value given in the manual, so if the keel is at 6.5m set for between 7.5 and 8. Then make sure your torpido is set up with a magnetic pistol, by defult they all should be, and let fly with your shot, well swim but you get the idea. The torpido will cruse in right underneeth the target and blow up somewhere underneeth it. This causes herendous damage to your target and negates the need for a 90deg shot in most situations; though the 90deg is still your best bet for a good hit. As for 90deg shots, range isn't all that important, as long as the target is inside around 1500m. The only time range realy matters is when your are realy close to bow on or stern on with your target, your extreem AOBs. The speed measuring with the map, the 3:15 method, your speed dosen't effect your results. At least not as far as I can tell. It is beacouse you are measuring the target's movment relitive to the Earth and not the target's movment relitive to you; at least that is how I understand it to work.