Complicated Math

[robj250]

Okay guys, here is the problem. First of all the navmap is 125KM size which 125 km = 54 mm and the time of the day is 1816. I have a convoy 79° from me at a distance of 170 mm on the nav map, they are on a course of 247.5° and travelling at 6 kts. I anticipate they have to travel along that course (247.5°) for a distance of 134 mm on that nav map. What time would it be when they reach that 134 km point?

Next, I plan to intercept them on a bearing of 108°, the distance on the nav map is 45.5mm when they have travelled 134 mm on the nav map. What time would it be when I arrive at my point if I travel at 17 kts.

6 kts/24 hrs = 267 km
17 kts/24 hrs = 756 km

Can anyone solve this for me. My brain just cannot comprehend it :oops: :damn:

Have I supplied enough information?

[El Dude]

42

[VipertheSniper]

the 134mm on the map are approx. 310 km, your distance to the convoy is approx. 393km, the interception course is approx 105km long, you could as well run at 6kts and still intercept them, you being there earlier won't help you much in terms of light conditions, I'd rather go for a longer interception course where you reach the convoy earlier, because for 310 km they'll need about 27 hours, so you would attack them at about 2100... I think I'd go for a course that intercepts the convoys course at a bit more of an angle than the 139.5° you're going for, in 12 hours you'll make 378km at 17kts so I'd draw a circle around your boat in the nav map with 360 km radius, plot a line of the targets course and head in the direction of the intersection point. That should give you enough time to set up nicely.

I could've just written: "use the map tools" right?

[VipertheSniper]

42

LOL HHGTTG

[robj250]

the 134mm on the map are approx. 310 km, your distance to the convoy is approx. 393km, the interception course is approx 105km long, you could as well run at 6kts and still intercept them, you being there earlier won't help you much in terms of light conditions, I'd rather go for a longer interception course where you reach the convoy earlier, because for 310 km they'll need about 27 hours, so you would attack them at about 2100... I think I'd go for a course that intercepts the convoys course at a bit more of an angle than the 139.5° you're going for, in 12 hours you'll make 378km at 17kts so I'd draw a circle around your boat in the nav map with 360 km radius, plot a line of the targets course and head in the direction of the intersection point. That should give you enough time to set up nicely.

I could've just written: "use the map tools" right?

I'm sorry, but I don't know how to use the map tools, that's why I have to try and figure it out by hand. But I'll take your suggestions. Thanks

[GreyOctober]

I hope it will clear some things for you. I made it to another scale (13.4 km). it more like a general example of how you should intercept.

http://www.hg-d.com/others/intercept.jpg

http://www.hg-d.com/others/intercept.jpg

Cheers!

[robj250]

I hope it will clear some things for you. I made it to another scale (13.4 km). it more like a general example of how you should intercept.

http://www.hg-d.com/others/intercept.jpg

http://www.hg-d.com/others/intercept.jpg

Cheers!

Actually GreyOctober, the positions are different, I'll see if I can get Imagewhatever to post the picture. Thanks

[GreyOctober]

The possitions might be different but infact the same rules apply when it comes to interception.

[robj250]

I am actually heading toward AE87 when I was informed of this large convoy on a course of 247.5° at 6 kts.

http://img138.imageshack.us/img138/7519/theirroute0wj.jpg

[robj250]

I am actually heading toward AE87 when I was informed of this large convoy on a course of 247.5° at 6 kts.

There, I got it bigger in the above post. Thanks
Now if you can relate you explanation to my map then I would understand it better.

[zzsteven]

The link worked Robert.

zz

[GreyOctober]

btw, to display an immage put the link in between [img] [/img] tags

[img]http://img138.imageshack.us/img138/5388/theirroute7ld.th.jpg[/img]

or select the link (as you select a normal text) and click the "IMG" button (third from the right just below the Subject textfield) in the message composer

[robj250]

btw, to display an immage put the link in between [img] [/img] tags

[img]http://img138.imageshack.us/img138/5388/theirroute7ld.th.jpg[/img]

or select the link (as you select a normal text) and click the "IMG" button (third from the right just below the Subject textfield) in the message composer

I've printed out your map to see if I can "comprehend it" You know how difficult it is for me to understand things sometimes :oops:

Darn :damn: Now I forget how to get my signature picture back in so that a person can link on it to see the fate of U51 :damn:

[robj250]

This is the code I have in my signature:

GOOD HUNTING FOR EVERYONE! Go get 'em!

http://img124.imageshack.us/img124/8625/viibuboateditblue22ln9ar.jpg (http://www.boat.net/boats/u51.htm/)
Thanks to everyone who have given me help and good recommendations, it is greatly appreciated.

This is what I have in the signature: {color = green} Good hunting --- {/ color}
{url=http://www.boat.net/boats/u51.htm/}{img}
http://img124.imageshack.us/img124/8625/viibuboateditblue22ln9ar.jpg{/img}{/url}
{color=red}Thansk -----{/color}

The { would actualy be a [ etc. Whats wrong, because my image picture is not showing?

What's wrong with it GreyOctober?

[robj250]

the 134mm on the map are approx. 310 km, your distance to the convoy is approx. 393km, the interception course is approx 105km long, you could as well run at 6kts and still intercept them, you being there earlier won't help you much in terms of light conditions, I'd rather go for a longer interception course where you reach the convoy earlier, because for 310 km they'll need about 27 hours, so you would attack them at about 2100... I think I'd go for a course that intercepts the convoys course at a bit more of an angle than the 139.5° you're going for, in 12 hours you'll make 378km at 17kts so I'd draw a circle around your boat in the nav map with 360 km radius, plot a line of the targets course and head in the direction of the intersection point. That should give you enough time to set up nicely.

I could've just written: "use the map tools" right?

Thanks VipertheSniper. I took your advice, but I did it the "eyeball" method. I went on a course of 139° and I intercepted them July 25 at 0129. So far I have sunk 2 destroyers and 2 merchants. Not finished yet as I have lots of torpedoes left. Thanks again. I really appreciated your advise even though I don't know how to use the "tools"

[Keelbuster]

Intuition seems to serve me. I measure the distance they have to travel to the contact point, and I measure my own.
Then I compensate with my speed (i.e. go twice their speed). It seems to work; once I have a radio report I can usually catch them.
Anyway - the radio reports I get are vague (ie. travelling NW at 8kts). I can't do any exact work, except to get in their area at the right
time. It's coarse, on the scale of intuition.

Kb

[robj250]

Intuition seems to serve me. I measure the distance they have to travel to the contact point, and I measure my own.
Then I compensate with my speed (i.e. go twice their speed). It seems to work; once I have a radio report I can usually catch them.
Anyway - the radio reports I get are vague (ie. travelling NW at 8kts). I can't do any exact work, except to get in their area at the right
time. It's coarse, on the scale of intuition.

Kb

I got tired of getting the NW etc, direction so I made changes to the cfg file, I forget which one at the moment and put in the degrees - 0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, and 337.5°. I like that much better 'cause it gives me degrees to work with. :up: Robert

[Keelbuster]

Intuition seems to serve me. I measure the distance they have to travel to the contact point, and I measure my own.
Then I compensate with my speed (i.e. go twice their speed). It seems to work; once I have a radio report I can usually catch them.
Anyway - the radio reports I get are vague (ie. travelling NW at 8kts). I can't do any exact work, except to get in their area at the right
time. It's coarse, on the scale of intuition.

Kb

I got tired of getting the NW etc, direction so I made changes to the cfg file, I forget which one at the moment and put in the degrees - 0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, and 337.5°. I like that much better 'cause it gives me degrees to work with. :up: Robert

Robert - nice edit - did they have that kind of intel? Also - how are these reports generated (i.e. in real life)? This is an old topic, but i didn't get (or just forgot) the answer. Are these sightings or DF intercepts?

Kb

[robj250]

Intuition seems to serve me. I measure the distance they have to travel to the contact point, and I measure my own.
Then I compensate with my speed (i.e. go twice their speed). It seems to work; once I have a radio report I can usually catch them.
Anyway - the radio reports I get are vague (ie. travelling NW at 8kts). I can't do any exact work, except to get in their area at the right
time. It's coarse, on the scale of intuition.

Kb

I got tired of getting the NW etc, direction so I made changes to the cfg file, I forget which one at the moment and put in the degrees - 0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, and 337.5°. I like that much better 'cause it gives me degrees to work with. :up: Robert

Robert - nice edit - did they have that kind of intel? Also - how are these reports generated (i.e. in real life)? This is an old topic, but i didn't get (or just forgot) the answer. Are these sightings or DF intercepts?

Kb

Daily contact reports

[lurker_hlb3]

Using "real world" course to intercept on a USN Moboard

Course to station 082 / 17kts
relative speed 24 kts
time on course 425 minutes
time to station 0121

[tbarak]

I think the km to mm conversion is confusing.

Here's what I get:

kph to knots conversion (x = 1.8522)

Convoy's speed = 6x = 11.1132 kph

336.5/11.1132 = 30.27 hrs.

Your speed = 17x = 31.48 kph

You didn't plot your course and I don't see any protractor marks so lacking a probable intercept point, if you went 90 degrees to the angle of the convoy's travel:

70/31.48 = 2.22 hours

So if you did a 180 from your current position and high-tailed it at flank, your time would be 18:16 + 2.22 hours so approx. 20:30 - for a position of 90 off the convoy's extrapolated course.

Otherwise measure the distance in km from your current position to the exact point you want to reach (108) and divide that by 31.48. Either way get the deck of cards out since convoy isn't due for a while.

Too bad the search feature on the forums isn't good anymore, since there a few posts you should explore that show some nice ways to get good fire angles using just the map. Your map sample sorely needs more protractor and compass marks. I find myself marking the hell out of the nav map, using the compass generously to work in ranges rather than precise positions. Marking a lane for the convoy's guessed path helps to account for course changes.

I just bee-line it to the convoy on contact, submerging time-to-time to get a fix once they're near, attacking at night and/or in foul weather for best results.

[don1reed]

Hey, Robert.

Here's something you ought to read:

http://www.subsim.com/phpBB/viewtopic.php?t=48026

and this;

http://www.subsim.com/phpBB/viewtopic.php?t=49376&highlight=

rgds,

[robj250]

Thanks for posting those links for me. However, I do not use RUb1.45. Nevertheless, the information provided is useful to me. :D

[robj250]

U-Boat Captains in WWI and WWII did not have all the fancy tools that Mods have made available in Silent Hunter III.

All they had was something like the mathematical set of dividers, protractors, ect. (that comes in a kit) and had to manually plot an intercept, similar to what I had to do in order to calculate an intercept point.

That's the way IT should be done, instead of all the fancy stuff we have in the game. :up:

[robj250]

I think the km to mm conversion is confusing.

Here's what I get:

kph to knots conversion (x = 1.8522)

Convoy's speed = 6x = 11.1132 kph

336.5/11.1132 = 30.27 hrs.

Your speed = 17x = 31.48 kph

You didn't plot your course and I don't see any protractor marks so lacking a probably intercept point, if you went 90 degrees to the angle of the convoy's travel:

70/31.48 = 2.22 hours

So if you did a 180 from current position and high-tailed it at flank, your time would be 18:16 + 2.22 hours so approx. 20:30 - for a position of 90 off the convoy's extrapolated course.

Otherwise measure the distance in km from your current position to the exact point you want to reach (108) and divide that 31.48. Either way get the deck of cards out since convoy isn't due for a while.

Too bad the search feature on the forums isn't good anymore, since there a few posts you should explore that show some nice ways to get good fire angles using just the map. Your map sample sorely needs more protractor and compass marks. I find myself marking the hell out of the nav map, using the compass generously to work in ranges rather than precise positions. Marking a lane for the convoy's guessed path helps to account for course changes.

I just bee-line it to the convoy on contact, submerging time-to-time to get a fix once they're near, attacking at night and/or in foul weather for best results.

I'm sorry that you find manual paper calculations confusing. But as I mentioned in a post on the subject, U-Boat captains did not have access to the wonderful mods that does all the work for you. Learn how to do it manually and you've become a good excample of what they had to go through to intercept an enemy convoy.

[VipertheSniper]

All the fancy stuff we have in the game? so we can draw lines like you would do with a ruler, draw circles with a circle, tick marks with a pencil, measure an angle like you'd do with a protractor, and finally a rubber... WHAT fancy stuff are you talking about?

[robj250]

All the fancy stuff we have in the game? so we can draw lines like you would do with a ruler, draw circles with a circle, tick marks with a pencil, measure an angle like you'd do with a protractor, and finally a rubber... WHAT fancy stuff are you talking about?

I'm sorry, but I have not yet learned how to use the ruler, protractors, etc yet and what I'm talking about are the mods that provide the extra plotting stuff. I am sorry about my ignorance and inability to understand how to use this plotting assistance. I've always done it by "eye-balling" and a pencil and paper and I've had no problems intercepting convoys yet. My method works just fine.

[don1reed]

That's the way IT should be done, instead of all the fancy stuff we have in the game.

lol

Don't put too fine a point on it, Robert, the U-Boat skippers didn't have computers either. :lol:

Cheers,

[robj250]

That's the way IT should be done, instead of all the fancy stuff we have in the game.

lol

Don't put too fine a point on it, Robert, the U-Boat skippers didn't have computers either. :lol:

Cheers,

That's very true. However, just because I cannot comprehend on using the tool method, I should not be criticised. Good hunting everyone. My method hasn't failed me yet. :D

[tbarak]

You shouldn't feel bad because you're new and still learning and don't misinterpret they're responses as an attempt to embarrass you. These guys are all pretty cool, serious and mature and I figure they debate as seriously as they play the game. It's all in good fun and we all share the common desire to learn and enjoy the game and community experience.

I don't like the km to mm conversion since your ruler is more precise than trying to measure lines on the map in mm then doing the conversion. Neither way is right or wrong and I'm just expressing my preference.

The tools seem complicated but just play around with them. For example all the compass does is draws a circle with a radius measurement mark. Left click where you want the centre of the circle to be, drag the circle out and release the mouse once its the size you want. It's like the ruler but with the benefit of a circle drawn with a radius that you're measuring.

The protractor just measures angles - that way you could plot that 108 degree angle of attack you want to achieve. To use it, left click and drag out a line along the convoy's path, click to place a point then drag out another line. You'll see an angle indication that measures the angle between the two lines. Try it and I think you'll get the drift of it.

Since I play at 57% realism I use my plots to get a rough estimate of where the convoy will be. I then use sonar to fine tune the approach, finally using the periscope intermittently for the final attack run. With higher realism setting (next career) the measurements will have to be more precise but for now, like you, I'm still learning the game. GL Kaleun.

[robj250]

I really do feel badly that I find it confusing in using the tools from the slide-out at the top of the NavMap. However, I have spent all day so far, since 5 AM until now 3:15 PM, copying two methods of plotting and printed them out as well as printing the pictures that went with the two methods. I have now made a manual for plotting. I will keep trying to comprehend the use of these tools. However, at the moment I don't think I could add any further plotting bearing mods, 'cause that would confuse me even more. I do not use RUb1.45 'cause I don't like it as it had taken away a portion of SH3 that I prefer; but no matter. I'm getting there. I have (I think) installed all the mods that I want and as soon as I sink every ship in this convoy and return to base, I am thinking of installing SH3 Commander. Now I know there is a lot of reading I have to do there as well, but guys talk so much about it, so it must be a good feature. I prefer the German ranks, but everything else in English. I don't know if I can configure SH3 Commander v2.5 to do that.

I installed the sound trainer in the single mission folder and I find it diffuclt to use that. So I could use bearing reported by SO that I could use to my advantage. I wish there were instructions for it.

I installed two manual targetting mods in the single mission folder so at least I am taking every step I can to try to understand both NavMap plotting and manual targetting.

So, as you can see, I'm trying, but my mind is getting too 'boggled' at the moment.

I really hope to understand all this and be able to do everything before I actually finish the war :D :up: Any constructive assistance is certainly appreciated.

Another thing I did that really helps me out is that I changed the NW, ENE, etc. to actual bearings on the compass, so I can understand it better.

Another problem I have now is that there is a space between the words at the top of my signature before the picture, where there was no space in the original signature I put up. I cannot figure out how to get rid of that space without screwing up the link to the fate of U51 or losing my signature jpg all together.

However, guys have been trying to help, and as I say at the bottom of my signature, the help is greatly appreciated. I think a lot of the guys are starting to understand why I have such problems understanding things.

Thanks for writing. Robert

Oh, btw, I keep both a written report and a photographic record of my patrols at:

http://spaces.msn.com/subguy2a/

A person can learn a lot of what I have done throughout my life before becomming incapacitated by visiting that link. Especially when they read the first archive in March which tells about my life, what I did and that a have a second chance at life.

However, I realize that there are others that are far worse off than I am, and my prayers go out to them.