Question about AOB

[ddiplock]

Can you only use the formula 180-bearing to calculate teh AOB only when your travelling perpendicular to your target?

or can you use it anytime to calculate the AOB??

because I used that formula just now to fire at a small merchant heading towards me at about 900mtrs, the torpedos missed the target, and just missed his rear end, even though i fired slightly "ahead" of him if you get me?

[Hitman]

If you are heading perpendicular to a target, the AOB is 90º

The AOB is not dependant on your true course, but simply on the angle from the target's course to his bearing of your submarine.

[P_Funk]

AoB can be a real pain in the butt. Its the one that took me the longest to get comfortable with.

But if you know your course and his course and the bearing to target due north then you can figure it out.

[Platapus]

Just to make things completely confusing

Originally Posted by Hitman

If you are heading perpendicular to a target, the AOB is 90º

However the opposite is rarely true: if the AoB is 90 degrees that does not always mean you are heading perpendicular to the target.

You are right, only in the case where you are heading perpendicular to the target will AoB be the reciprocal of the bearing to the target. Any other heading and the AoB will not equal the reciprocal of your bearing.

I feel that the term AoB is confusing and should be changed to AOBOTGWWBESOYTs* for clarity.

*Angle off the bow of the guy who will be eating some of your torpedoes soon.

This is much easier to understand. I don’t know why the navy did not adopt my initialization before. LoL

[P_Funk]

Originally Posted by Platapus

This is much easier to understand. I don’t know why the navy did not adopt my initialization before. LoL

Because the navy is like all other military institutions. They suck at writing. Thats why they flunked out school and became career soldiers. Thats not their specialty. Plus its only misleading when you have a fractured understanding of it which most people in the navy wouldn't, unlike us who get barely understandable manuals and a forum who's search function I have never understood properly.

[Platapus]

I don't know if it is still true, but back in my younger military days, a specific office of the Navy was responsible for developing and maintaining acronyms and initializations for the United States government.

I read the list of standard initializations and found that the United States Navy found it necessary to initialize the word "FLAG" to "FLG". I am sure removing that expensive "A" saved the government much money and time.

[Hitman]

I probably gave a confusing answer unitentionally. I meant that AOB is 90º when you are perpendicular to the target, not only to the target's course. What I meant is if you have the target right in front (Bearing 0 for you) and he is heading perpendicular to you, either left of right, then the AOB is exactly 90.

For all other situations, do what follows:

1.- Draw a triangle where one corner is your sub, the second the enemy vessel and the third is where your course and the target's course meet (X point in the scheme below).


X----------<======> TARGET (Heading left here)
I
I
I
I
I
I
I
U-BOOT (Heading up here)

Angle 1 is the one that goes from you 0 bearing to the target bearing (Approx 45º in this case).

Angle 2 is the one that goes from your course to the target's course (90º in this case, at meetpoint "X").

Angle 3 is the one that goes from the target's course to the target bearing of your sub. That is the AOB.

Now, because in every triangle the sum of all its angles is ALWAYS 180º, and because you know the value of two of the angles (45º from your bearing to target and 90º from having your course perpendicular to the target's course), then 180-90-45= 45. The AOB in this case is 45º


Hope that clarifies it all a bit more.


What makes it so confusing is that everyone seems to be using the AOB for exactly the opposite purpose it was created. :hmm: The AOB used because when being at sea level in your UBoot and first spotting a target, the only way you have to figure out where it is heading to (The course) was guesstimating how much left or right from a direct collision course with you was the target heading. Once time goes by and more observations have been done, the AOB becomes irrelevant as you have now enough stuff to plot the real target course, which is what in fact is of interest for you, and not the dreaded AOB.

But since the SH3 TDC works exactly the opposite as the german historic TDC (In which you entered target's course, and not the AOB, that changes constantly) people in the forum have ended up building up wrong procedures for manual targeting, which fit to the game's limitations, but not to historical reality. Such is life.

[P_Funk]

Originally Posted by Hitman

But since the SH3 TDC works exactly the opposite as the german historic TDC (In which you entered target's course, and not the AOB, that changes constantly) people in the forum have ended up building up wrong procedures for manual targeting, which fit to the game's limitations, but not to historical reality. Such is life.

That is is exactly it. In fact if you think about it AoB is the hardest thing to get right for noobs. So manual TDC is so much more complicated than it even needs to be.

Such a pile of nonsense really. I can get Target course, speed, and range all in one 3 minute go. Oh lord if we got an SDK theres only one thing that I'd really want.

[Heibges]

Yep, the AOB you need is the one at your Firing Point, which in the real German TDC would have been calculated automatically.

I generally fire at 80° pt/stb for most targets, and 70°pt/stb for fast moving or long range targets.

[P_Funk]

Here I found this in the SH4 forums:http://spidermine.com/SHIII/wheel.swf
Its a flash animated version of the AoB wheel that you can dload here:http://files.filefront.com/AoB_wheel.../fileinfo.html

Very handy.

Though I've found that this equation seems to work as well:
AoB=Target True Bearing - Target Course +/- 180

the +/- is dependant on whether its port or starboard.

[Hitman]

The sad thing is that in Silent Hunter 2 the TDC was absolutely perfect. And because you did input the target course and speed, and the bearing was updated as you moved your scope left or right, it allowed you firing at multiple targets that share both course and speed but not position (A convoy, to be more precise) just by looking at the next target and firing.

So easy....you get a convoy course and speed. Put your crosshair in the first target, f.e. bearing 10, fire 1, move scope right to next target, f.e. bearing 25º, wait some seconds until TDC computes all according to new bearing and when green light comes (Solution ready) then fire 2!...and so on. That's how germans did it in real life