Range determination

Kanelglass · 07-30-07, 10:23 PM

Hi guys ! My biggest problem when it comes to manual targeting is range determination. Then I'm talking about the stadiometer. I'm pretty good with it when the weather is calm, but as quickly there is a tiny wave, everything goes wrong.

I already know that I can move the periscope at the same time I'm mixing with the stadiometer, but it's still hard.
Could you give me some advice ?
Thx.

joegrundman · 07-31-07, 12:03 AM

it IS one of the hardest things to get to grips with in this game, and if you rely on bearing plots to obtain your solution it becomes an even bigger problem, as errors in range lead to errors in target course and speed.

There are a few things you can do to improve your chances.

Firstly, focus on other methods of getting target course, inlcuding your ability to judge AOB by eye. AOB + poor range estimate is more accurate than two poor range estimates. Also try using the aspect ratio method of getting a good AOB

Secondly, focus on obtaining speed estimates by other methods than bearing plots. Errors in range with this method also lead to large errors in speed estimate. Using the slide rule on a whiz wheel is one way to find target speed, which in short means you try to set up a collision course with the target typically on your beam (ie bearing 90/270 from you). Also you can get speed estimates by observing the time it takes for the ship to cross a fixed point, e.g. your periscope cross hairs. you have to be moving slow, but then you can divide the length of target by time to get speed in m/s. double this to get speed in knots.

Thirdly, if you really want to get a bearing plot, plan on getting a large number of bearings plots in order to even out inaccuracies

Fourthly, focus on closing the gap until the range is close enough that errors become less signiricant, fro example by holding the target on a normal approach course of 90/270 degrees.

Fifthly, if the weather is very rough it can be easier to just count the marks on the periscope and do the maths yourself to find an approximate range (also to be done if you have to use your obs scope for targeting)

With all these methods working together, poor weather is just a little challenge. If you are playing GWX you find the disadvantage of rough weather is much more than compensated for by the bad effect it has on your enemies sonar

Kanelglass · 07-31-07, 12:36 AM

Thx for your advice !
I have just started with counting marks in uzo/periscope. It's like you said, it's definitive better to count marks in bad weather.
Now I have much to work on to improve my "aim".

I didn't know about the sonar, that's cool !
For now on, I'm going to love bad weather

Thx again !

BarjackU977 · 07-31-07, 01:21 AM

I also use the periscope marks, in rough waters. I "unlock" my target, and put the vertical line with marks on the highest mast, while I try to keep the middle horizontal line on the waterline with the mouse. Once I was where the mast is, I click on the stadimeter icon, and put the stadimeter horizontal line where the mast was.

frenema · 07-31-07, 10:48 AM

I just try to get an estimate first then go as close to the target as possible for more precise measure (or wait for the target to come close). At a close range your estimates are pretty close no matter how rough the sea is.

Puster Bill · 07-31-07, 11:42 AM

Another alternative is to use stabilized view. It only penalizes you 5%.

Klaus_Doldinger · 08-05-07, 03:45 PM

Quote:

Originally Posted by joegrundman

Fourthly, focus on closing the gap until the range is close enough that errors become less signiricant, fro example by holding the target on a normal approach course of 90/270 degrees.

Fifthly, if the weather is very rough it can be easier to just count the marks on the periscope and do the maths yourself to find an approximate range (also to be done if you have to use your obs scope for targeting)

With all these methods working together, poor weather is just a little challenge. If you are playing GWX you find the disadvantage of rough weather is much more than compensated for by the bad effect it has on your enemies sonar

So, if I´ve understood it correctly, the TDC is not useless, simply you must use it at a distance in which the errors will be irrelevant.

I´ll tell my own experience today. For hours I have been shadowing a convoy at 9.000 meters. From radio reports I knew that his estimated speed was 7 knots. At night I closed to the convoy. The calm with light fog had turned to 13mps winds with fog also. I submerged as the convoy made a course change and a escort closed to less than 4.000 meters, I didn´t wanted last minute surprises. I identified several ships and fixed a C3 at 1.500 meters, at 90º AOB more or less. The TDC gave me 7 knots. I fired without doubt and he received the two torpedoes, sinking ten minutes later. Without time to see the effect of the two first fishes I fixed a C2 at more or less 1.700 metres; the first calculation gave me 5 knots; I forgot it as in a convoy all vessels must have same speed and made a second calculation, 1.500 meters (rough seas made it difficult to keep the mouse to calculate height and I was very excited to calculate speed with the periscope crosshairs). The speed was 7 knots, AOB more or less 75º. I fired two torpedoes and BOOOOOOOMMMM!!!! (I only heard it as I ordered dive launching a decoy at the same time).

So... must I think that TDC really can work at close distance??

P.S.: I played GWX 1.03, 100%, no map contacts update.

I´d like to hear about your opinions. Thanks in advance.

joegrundman · 08-05-07, 08:04 PM

Sounds to me like you did just fine. Apart from that I don't fully understand your question

Quote:

So, if I´ve understood it correctly, the TDC is not useless, simply you must use it at a distance in which the errors will be irrelevant.

The TDC is not at all useless. It is an angle solver that will give a 100% accurate firing solution for a virtual target that corresponds to the AOB, range, speed and periscope bearing data that you input into it (I don't believe the game models errors in torpedo performance or the effects of water etc.)

It is your job to make sure that this virtual target corresponds to an actual target. To get an exact match is difficult, but because the actual target has a length, there is room for error. The closer you are to the target, the greater the amount of error you can include in your data while still being sure of hitting the target. If you have very accurate data, then unless the target manoevers, you will be able to hit the target even at maximum range.

Range is the least significant error factor, assuming you are firing on a gyro angle of 000, or close to it. (torpedo tube parallax causes large errors to develop if range is not accurate with large gyro angles). Let us assume that you are firing on a gyro angle of 000 with a torpedo travelling at 30kts against the middle of a 150m target travelling at 7.5kts (to make the maths easier). Assume AOB is accurately determined to be 90.

The torp is travelling at 4x the speed of the target, so for the target to have moved 150 meters from the intended point of impact, the torpedo must have travelled 150x4=600 meters. Therefore, 600m range is the margin of error (or +/-300m) you have in terms of range only to still hit a 150m target.

If you are firing from a range of about 1000m, this margin is an enormous percentage of error (+/-30%), but if you are firing at a long range of 5000 m, it is somewhat less (+/-6%). When using your stadimeter in rough weather, it is these percentages which are important.

You can also see that the margin of error is dependent on the length of the ship, therefore, aim for the big ones! You can also improve your chances when there is reason to doubt your data by using a spread pattern. You can also improve your margin of error by using faster torpedoes.

Obviously errors in speed and AOB, and range inaccuracies when using larger gyro angles greatly increase the error, but again shorter range reduces the chance of a complete miss

Canovaro · 08-06-07, 01:22 AM

Quote:

Originally Posted by Klaus_Doldinger

P.S.: I played GWX 1.03, 100%, no map contacts update.

I´d like to hear about your opinions. Thanks in advance.

My opinion is that you launched a very succesfull attack at 100% realism!
Well done!

Stealth Hunter · 08-06-07, 03:31 AM

Estimate the range to target and speed by checking your navigation map. The ship's speed, class, and range are automatically calculated by him, so it's pretty much a walk in the park for the lesser difficulties.

Tobus · 08-06-07, 03:46 AM

Tips from my humble person:

- target a ship multiple times, thus getting a better and better solution
- Do the last targeting at range under 1000 meters, range will then not be a problem in targeting (and hitting!)
- when moving the scope, stadimeter or any other viewing-thingy, you can speed up movement while holding down SHIFT, but slow down movement while holding down CTRL. This is a little known fact I think, but especially in targeting (speed and range via stadimeter) this can be very usefull.

Always the basic rule remains: the higher the range to target, the worse your firingsolution will be.

07-30-07, 10:23 PM	#1
Kanelglass Seaman Join Date: Jul 2007 Posts: 42 Downloads: 96 Uploads: 0	Range determination Hi guys ! My biggest problem when it comes to manual targeting is range determination. Then I'm talking about the stadiometer. I'm pretty good with it when the weather is calm, but as quickly there is a tiny wave, everything goes wrong. I already know that I can move the periscope at the same time I'm mixing with the stadiometer, but it's still hard. Could you give me some advice ? Thx.

07-31-07, 12:03 AM	#2
joegrundman Ocean Warrior Join Date: May 2007 Posts: 2,689 Downloads: 34 Uploads: 0	it IS one of the hardest things to get to grips with in this game, and if you rely on bearing plots to obtain your solution it becomes an even bigger problem, as errors in range lead to errors in target course and speed. There are a few things you can do to improve your chances. Firstly, focus on other methods of getting target course, inlcuding your ability to judge AOB by eye. AOB + poor range estimate is more accurate than two poor range estimates. Also try using the aspect ratio method of getting a good AOB Secondly, focus on obtaining speed estimates by other methods than bearing plots. Errors in range with this method also lead to large errors in speed estimate. Using the slide rule on a whiz wheel is one way to find target speed, which in short means you try to set up a collision course with the target typically on your beam (ie bearing 90/270 from you). Also you can get speed estimates by observing the time it takes for the ship to cross a fixed point, e.g. your periscope cross hairs. you have to be moving slow, but then you can divide the length of target by time to get speed in m/s. double this to get speed in knots. Thirdly, if you really want to get a bearing plot, plan on getting a large number of bearings plots in order to even out inaccuracies Fourthly, focus on closing the gap until the range is close enough that errors become less signiricant, fro example by holding the target on a normal approach course of 90/270 degrees. Fifthly, if the weather is very rough it can be easier to just count the marks on the periscope and do the maths yourself to find an approximate range (also to be done if you have to use your obs scope for targeting) With all these methods working together, poor weather is just a little challenge. If you are playing GWX you find the disadvantage of rough weather is much more than compensated for by the bad effect it has on your enemies sonar __________________ "Enemy submarines are to be called U-Boats. The term submarine is to be reserved for Allied under water vessels. U-Boats are those dastardly villains who sink our ships, while submarines are those gallant and noble craft which sink theirs." Winston Churchill

07-31-07, 11:42 AM	#6
Puster Bill Grey Wolf Join Date: May 2006 Location: BA8758, or FN33eh for my fellow hams. Posts: 833 Downloads: 0 Uploads: 0	Another alternative is to use stabilized view. It only penalizes you 5%. __________________ The U-Boat Commander of Love

07-31-07, 12:36 AM	#3
Kanelglass Seaman Join Date: Jul 2007 Posts: 42 Downloads: 96 Uploads: 0	Thx for your advice ! I have just started with counting marks in uzo/periscope. It's like you said, it's definitive better to count marks in bad weather. Now I have much to work on to improve my "aim". I didn't know about the sonar, that's cool ! For now on, I'm going to love bad weather Thx again !

07-31-07, 01:21 AM	#4
BarjackU977 Gunner Join Date: Jul 2007 Posts: 97 Downloads: 6 Uploads: 0	I also use the periscope marks, in rough waters. I "unlock" my target, and put the vertical line with marks on the highest mast, while I try to keep the middle horizontal line on the waterline with the mouse. Once I was where the mast is, I click on the stadimeter icon, and put the stadimeter horizontal line where the mast was.

07-31-07, 10:48 AM	#5
frenema Torpedoman Join Date: Jul 2007 Location: Canada Posts: 116 Downloads: 8 Uploads: 0	I just try to get an estimate first then go as close to the target as possible for more precise measure (or wait for the target to come close). At a close range your estimates are pretty close no matter how rough the sea is.

08-06-07, 03:31 AM	#10
Stealth Hunter Silent Hunter Join Date: Nov 2006 Location: Y'ha-Nthlei Posts: 4,262 Downloads: 19 Uploads: 0	Estimate the range to target and speed by checking your navigation map. The ship's speed, class, and range are automatically calculated by him, so it's pretty much a walk in the park for the lesser difficulties.

08-06-07, 03:46 AM	#11
Tobus Lieutenant Join Date: Jun 2005 Posts: 260 Downloads: 13 Uploads: 0	Tips from my humble person: - target a ship multiple times, thus getting a better and better solution - Do the last targeting at range under 1000 meters, range will then not be a problem in targeting (and hitting!) - when moving the scope, stadimeter or any other viewing-thingy, you can speed up movement while holding down SHIFT, but slow down movement while holding down CTRL. This is a little known fact I think, but especially in targeting (speed and range via stadimeter) this can be very usefull. Always the basic rule remains: the higher the range to target, the worse your firingsolution will be.