Four bearings...

[Shkval]

Well, I'm playing SH3 again after a long time, with GWX3.0 gold an MaGui mods... and I have a few questions, first, this situation in picture, contact is moving away and when I try to copy first bearing on a symmetrical point it does not intersect with last bearing... what does it means and what should I do?

Second question is does anybody knows some good tutorial about these tools in MaGui mode, attack disc, this second "brown" disc that has something to do with AOB,...and this third disc attached to periscope?

I got this Angriffsscheibe_Handbuch_3 pdf for attack disc but it's pretty different from this one in MaGui, and off course two "main" tutorials about hydro-hunting... I need more...

I'm practicing the four bearings method because I like this "mathematical" approach of aiming torpedoes and because I intend to survive the war . I'm not a total beginner but for the first time I'm playing with "map turned off" feature... and it's bloody difficult... yesterday I did mine first "blind" hit at 4,5 km .

[Mittelwaechter]

Just two comments:

- remember your bearings are cones - resulting in unavoidable inaccurate drawings. Our SH3 map tools were not designed for this task. Still good enough for a fire solution at 'short' distances but the further you shoot the more luck you'll need. Hits over 4500 meters are possible but you'll be frustrated by the work you invest versus the score you get.

- don't go for targets sailing away. ^
Get into better position or let them go.

[Pisces]

One of the circular wheels you describe is probably my 3-bearing AOB calculator. If doesn't calculate speed or range. But it could help to verify the correctnes of your drawing up to this point.

The 3 bearing AOB calculator is based on my design:

http://www.subsim.com/radioroom/showthread.php?t=147719

The MaGUI mod should have the explanation how to use it somewhere in the documentation files. But the above link explains it perfectly. (I hope) Align the differences between the specific bearings and read out the AOB at the first bearing. Then add the difference between bearing 1 and bearing 3 to the AOB in the window, to get the AOB at bearing 3.

The shown AOB is correct insofar you adhered to the equal time-interval requirement and not turning during the procedure.

[Shkval]

Ok, guys I got it, at least how AOB finder works... and how to get true course of a target with attack disc, my following question is: is it possible to get range from AOB and true course... without moving the sub? without triangulation?

[ETsd4]

Originally Posted by Shkval

my following question is: is it possible to get range from AOB and true course... without moving the sub? without triangulation?

True course, yes, true range no.


You have to understand what the soundman is telling you and what your drawings tell you:
(1)soundman rounds the bearing:
True 359.5° = 000° for the soundman
and
True 000.4° = 000° for the soundman.

(2)The arcs in the drawings are rounded:
True 359°30' arc = 000° arc in your drawing
True 000°29' arc = 000° arc in your drawing
etc.

With these 2 facts in mind the laws of probability says you have a 0.0000000007715 % possibility to get all your 4 bearings and all 4 arc drawings at once error-free on you nautical chart ...

See also http://www.subsim.com/radioroom/show...light=bearings

[Shkval]

So I have 0.0000000007715 % chance to hit him with single torpedo ? Well guys you really know how to cheer up somebody... is there a cure for sonar guy? Some mod? More precise drawing tools?

@ETsd4... how did you get this 0.75 precision, and I was thinking about some "AOB+Bearing= Range" magic formula/drawing in my question...

@makman94 ... I can see the mistake now... nice tutorials btw

Lately I constantly have some error in projected course of a target I don't know how much but it's not bigger than 7-8 degrees (I think...) when a target approaches on it's course sonar guy doesn't reads out "constant distance" as it should... but "closing" until about 35-40 degrees on my scope, then suddenly he changes to "moving away" . This happens no matter what way of tracking I use... moving... stationary... is this result of cumulative "round up" bearing errors? I'm off-course on the 90 degrees approach to projected course of a target.

[makman94]

Here you are Shkval ,
you must place the red marked point to the green marked point (look at pic)...etc



for the tool that pisces is talking you about ,''there really is no reason to'' use it once you ''know how'' to do your drawings on navmap .
the tool is not there for ''helping you to verify the correctnes of your drawing up to this point'' , navmap drawings are as much accurate as accurate your bearing readings are .
so, in case you are wondering why the tool is there then ,the answer is : alternative playing styles ...nothing more and nothing less than this,you choose what suits best for you.

[Pisces]

I really should know better than to respond to this...

Originally Posted by makman94

...

for the tool that pisces is talking you about ,''there really is no reason to'' use it once you ''know how'' to do your drawings on navmap .
the tool is not there for ''helping you to verify the correctnes of your drawing up to this point'' , navmap drawings are as much accurate as accurate your bearing readings are .
so, in case you are wondering why the tool is there then ,the answer is : alternative playing styles ...nothing more and nothing less than this,you choose what suits best for you.

I suggested he used this tool because he suspected, or almost knew for certain, that he made a mistake in his drawing! So there IS a reason to verify the angles in the drawing! At the time of posting I couldn't provide detailed instructions how to correct his drawing because of time constraints and lack of editing ability. Otherwise I would have helped more. I just gave him another tool for finding the correct values. (based on same geometry and math) If they didn't match then the drawing was likely at fault. Wether Shkval would have been able to trace the error from it is another matter. But that's where follow-up posts are for. But he seems to have solved it allready. Case closed.

You may have had multiple reasons (or playing-styles in mind) for adding my wheel to your mod, but I had my own reasons for making it in the first place. One of it was infact verifying my drawings for errors and projecting the 4th bearing.