Nibelung

[Kip336]

Hey guys

Welp, first post

I started playing SHIII a while ago, and finally got to the point of commanding the XXI for the campaign. I read in the manual that the XXI has an advanced sonar, that can provide me with all the information needed to make an torpedo hit the target.

This is where Im stuck: As soon as I go into the Sonar room, I can scroll the dial around, and get a target bearing. I can ping to get the range, but how do I get the other information I need, like the AOB?

[irish1958]

Sonar can't give you AOB.
Welcome aboard.

[Kip336]

so the only information it gives is bearing and range? ...they need to edit the manual then...

How do you then work out the solution without the periscope?

[meduza]

Plot the ship's course on the map. Once you know the course, you know the AOB.

Welcome aboard!

[Kubryk]

Originally Posted by meduza

Plot the ship's course on the map. Once you know the course, you know the AOB.

Can you give me an exact formula? Using 3:15 I often end with having both mine and target's true courses, if I could calculate AOB I wouldn't have to do a 90 degrees aproach, which would be a nice change.

(best change would be playing again, I used JSGME with couple of mods and my game is broken, I don't have patience to check which one causes the problem. Am SH-free for more than 2 weeks now )

[meduza]

Originally Posted by Kubryk

Can you give me an exact formula? Using 3:15 I often end with having both mine and target's true courses, if I could calculate AOB I wouldn't have to do a 90 degrees aproach, which would be a nice change.

You don't need the formula to get the AOB.
When you know the course, you can find the AOB in two ways:
1. using the Attack disk that comes with certain modes (U-jagd tools and OLC GUI, and maybe some other). That's the method I use, but the other way around - to get the course out of the observed (estimated) AOB.
2. by plotting on the map. You have to know exact position of the ship, i.e. the range.

Once you've plotted the course, use the protractor tool. stick one end somewhere along the course, in front of the ship. Stick the second end to the position of the ship, and third in your position. The angle you get is the AOB.

[Hanomag]

Welcome Aboard Herr Kaluen!!

[Kubryk]

Originally Posted by meduza

2. by plotting on the map. You have to know exact position of the ship, i.e. the range.

Once you've plotted the course, use the protractor tool. stick one end somewhere along the course, in front of the ship. Stick the second end to the position of the ship, and third in your position. The angle you get is the AOB.

Thanks,

but I'd still like to learn the formula, just for fun.
That way I can calculate when in periscope view.

[Jimbuna]

Welcome aboard Kip336

Meduza method is the simplest/best for AOB

[Sea Hawk]

Originally Posted by Kubryk

Thanks,

but I'd still like to learn the formula, just for fun.
That way I can calculate when in periscope view.

Its all about the 3 angles of a triangle add up to 180

1st angle is the AOB of the target.

2nd angle is the targets bearing in degrees port or starboard of 0' either the bearing as read from the scope or if greater than 180' then 360-scope bearing

3rd angle is the angle between your heading and the targets heading, either (your heading - target heading) or (target heading - your heading) depending on which is the larger of the 2.

ie
target bearing port or starboard from 0' = TB

AOB + TB + differance between the headings = 180

AOB = 180 - (TB + differance between the headings)

But it is far easier to use the angle tool on the chart.
If you have "OLC gold" then the wiz wheel/attack disc gives you the AOB in seconds.
You can make an attack disk to hold in your hands if you prefair.

[meduza]

Originally Posted by Sea Hawk

AOB = 180 - (TB + differance between the headings)

That's the formula, but it's not that simple as it doesn't cover all situations.

Knowing the difference between headings (i.e. your heading - ship's heading) is sometimes not enough, because we need the angle between them. To get the angle we sometimes must subtract that difference from 360, or 180.

And if the AOB is greater than 90, i.e. the ship is moving away, the result given by the formula must be subtracted from 180 to get correct AOB.

[Sea Hawk]

Originally Posted by meduza

That's the formula, but it's not that simple as it doesn't cover all situations.

Knowing the difference between headings (i.e. your heading - ship's heading) is sometimes not enough, because we need the angle between them. To get the angle we sometimes must subtract that difference from 360, or 180.

And if the AOB is greater than 90, i.e. the ship is moving away, the result given by the formula must be subtracted from 180 to get correct AOB.

Thats why I included the following rules:-

Originally Posted by Sea Hawk

2nd angle is the targets bearing in degrees port or starboard of 0'

3rd angle is the angle between your heading and the targets heading, either (your heading - target heading) or (target heading - your heading) depending on which is the larger of the 2.

[Sea Hawk]

Oh, I see, if both you and target are traveling northwards over 270' or less than 90' heading then the differance between the 2 headings is subtracted from 360'.
Thanks Meduza

[meduza]

Originally Posted by Sea Hawk

Oh, I see, if both you and target are traveling northwards over 270' or less than 90' heading then the differance between the 2 headings is subtracted from 360'.
Thanks Meduza

That's right. And if, for example you are heading on 5, the target on 130, bearing 22, you'll have to subtract the diference from 180. And you'll have to subtract the result from 180 to get the AOB.

I think we all agree that it's better to use attack disk or tools on the map.

[Sea Hawk]

It just goes to show how impressive the attack disc is when you try to work out the geometry.

If I did use a formula for this (which I dont) I would still have to draw a diagram inorder to work out the formula.