Hidrophone atack

[bojan811]

I feel like a jackass...I will try to do it more precise.

Tell me something are your boats change course oftenly.I just pick up a aob and in few second he already change it.They just cant keep a steady course.
In the tutorial it appears to me that he is on a steady course.

I`m using some mods could it be that they cause this behavior?

I can`t be that stupid (I think )...I will keep on trying.
Thanks for the patience.

Best regards Bojan

[Mittelwaechter]

Hi Bojan,

the contacts do frequently change their course (at a scripted waypoint). It's pure coincidence to happen while hunting by hydrophone, but it happens.

The AOB changes/grows! rapidly with the contact coming closer to your position. If it grows and decreases alternately the contact is zigzaggin' - obviously under attack - or it sighted you or an other enemy.


Keep on the good work, I like your attitude!

If you are running GWX3.0 I could setup some training missions for you,

- straight course guaranteed!

[Pisces]

Originally Posted by Mittelwaechter

Edit: I checked your screenshots.

How comes A2 is smaller than A1?
Have a look at your 2.3 circle to add "s" - does it match the criterias? Does the second bearing cut the courseDIRECTION into two equal parts between first and third bearing? It should be a hint something is wrong.

Assuming A1 and A2 are correct - you made a mistake at the auxillary drawing.

[removed image link]

The AOB is 11° - not 37°.

The 'side' you choose for the auxillary drawing is not important. I mentioned it in the Konrad story but it is not necessary to care for.

For an incoming contact the AOB must be smaller than 90° (in SH3 smaller than 60° !!)

Is your U-Boot at full stop for the first three bearings? Do you stop for the crossbearing? Try to mark the point of the crossbearing.

Draw the 20 km bearings from the outside/the circleline onto your boat and move them like I did it in the tutorial. Remeber the bearing is a "cone" of 350 meters width on the hydrophonecircle. Try to center the bearingline to minimize error.

Try to work as exact as possible to counter the inaccuracy of the SH3 maptools.

Let's call it a day!

Regards

Mittelwaechter

I'm sorry Mittelwaechter, but I think you are wrong. You seem to have switched the bearing differences around. Based on the bearings that Bojan provided (B1=294, B2=298, B3=301) I believe it must be moving away. See that the 2nd bearing difference (between B2 and B3) is only 3 degrees, and the first bearing difference (B1 to B2) is 4 degrees. If the bearingdrift slows down (less degrees in the same time) then it (must) means that the target is moving away, and therefore have an AOB bigger than 90 degrees. As the target closes the change in bearing speeds up until it has an AOB of 90 degrees, but as it moves further and away is slows down again until it a crawl. But just one degree of slowdown in drift is not enough to make a good judgement because it could have resulted from rounding off the numbers that the crew does. I really advise to take more time than 9 minutes in this case to make the differences diverge more. Especially if you (Bojan) are trying to learn this.

According to the formula that I based my tool on (I've mentioned it in other thread so I won't repeat it here unless Bojan is curious ), the AOB should be 153 degrees based on the first 4, then 3 degrees of bearingdrift. Bojan mentioned the target must have had an AOB of 26. I can only make sense of that together with the bearings given, if he looked at the 'angle on the stern' instead of the 'angle on the bw'. Because it looks just like it. (153=180-27)

[Mittelwaechter]

Nice observations Pisces - I was thinking about this problem too.

My question was: why is A2 smaller than A1? Your conclusions are correct at the first sight.

But if you consider the provided information of the hydro operator on the first screenshot Bojan's contact is closing.

I guess it's a rounding error - or Bojan's U-Boot was moving slowly.
Or he didn't hunt only one contact.

I'd like to know how (and at what time) Bojan checks the real AOB to compare it with his drawings.

Bojan: how do you determine your 26° AOB?

[bojan811]

For that purpose i turnd on the auto targeting.
When I ponted the periscop at the targeted bering my sound man gave to me it pop up and the bow was 26 degree.
So he was coming at me. But the drawing i did showed that he is at least 11 km far but actualy he was at 4-5 km.

I took the reading`s just like you told me to.
Waited that the diference between 1st and 2nd to be at least 3 degree, and I remeberd the time (9 minuts),so I used that same time to get the 3rd beringline. Draw the triangles and copied the angle.Was not sure was it from right to left ok so I did both and gained 37 and 135.Because he was closing on me I used a 37 angle but as you can se it was wrong.

The angle gained by the drawing is actualy aob wright?!So if I copy it form the targets last known position It would give me the line wich would represent the targets real cours of heading.

And yes I am interested in any kind of help , tutorial misions as you metioned, I would aprishiate that wery much.
Pisces your sugestions are also welcome.
I was wondering what is that program that you use to draw those pictures?

Thak you both for your effort.You are wery good people.

Sorry for Eng I am from serbia.
Pozdrav

P.S. I envy you so much for all your knowledge.

[Mittelwaechter]

Hi Bojan,

I understand you know the correct AOB of the contact at the first bearing by using the auto target function.

The angle gained by the drawing is actualy aob wright?!So if I copy it form the targets last known position It would give me the line wich would represent the targets real cours of heading.

No!

The red angle of the auxillary drawing is the AOB at your first bearingline - not the AOB at last known position.
Copy the red angle onto your first bearingline and you get courseDIRECTION - not REAL courseline!

REAL courseline is parallel to courseDIRECTION through real position from crossbearing (fifth bearing intercepts "fourth bearing").

You can compare auto target AOB at first bearingline with red angle AOB - they should be identical - more or less

To get better results:
ask for constant contact reports and speed up the time.
Start with first bearing whenever the bearings change rate is ~ 1 per minute!
A six minute index will result in an angle of ~ 6° for your A1 and A2 will be even bigger.

This should make it easy for you to construct the auxillary drawing and the "tool error" is moderated too.
In my "33° AOB drawing" A1 was 10° and A2 was 16°!

__________________

The program is "Zirkel und Lineal" - http://zirkel.sourceforge.net/

__________________

For the training missions: do you run GWX3.0?


Your English is great for our communication!

[bojan811]

[img=http://img26.imageshack.us/img26/6363/bigtrouble.jpg]

Ok we have a new sitauasion.

Sound contact first at 360 ber. 9 min later 354 (84 angle) , 9 later 348 (2nd angle 84) so when I created drawing I got a 79 degree angle.

And then I put it on the my target course and for the first time in my life the "S" was the same on 1st and 2sn , and on 2nd and 3rd , it was 2,2.
Then I draw a 4th berinline , waited another 9 min , and got the 007(My name is Bond , James Bond :rotfl last bering. As you can see at the picture above it does not seem right to me.Sound man says he is closing on me.
But my probles is that me 4th imagine berinline is not intersectedwith a new bering 007.
How come. What am I doing wrong.

I`m so friken imberest of all you good people.You are trying so hard but i dont know what am I doing wrogn.It seems to me that you have iron nerves.

Edit:
I play on GWX 3.0!

Oh the program is just great.Thak you so much.Just to get a hang of it.

[FIREWALL]

I love doing Hydro Attacks. I don't find them complicatedand am usally sucessful.

I get alot of satisfaction from those kills.

[Mittelwaechter]

Hi Bojan,

did you check your auto target AOB in your last scenario?

It should have been ~ 84° at the first bearing. Strange your operator reports a closing contact.

At the second bearing the AOB must have been 90°.

And at the third bearing it must have been ~ 96° - in reality the contact is moving away now - but SH3 reports a constant distance to target, not a closing contact.

This is a very special situation Bojan.

A contact at the outer rim of the hydrophone circle doing a short trip through the circle (for ~ 12° in 12 minutes?) but beeing reported as closing all the time? Funny things happen.

Btw. - why did you change your interface?

[Pisces]

At the risk of confussing Bojan with a different technique, I suggest you watch this video by Nefelodamon. The AOB measurement technique is different, but it shows how much easier and accurate it becomes when you wait patiently for the bearing to move. (for example the time it takes for the bearing to move the first 10 degrees, do not wait until the bearings change quickly, take the 1st bearing as soon as you can and just wait) And you do not have to hurry yourselve and become nervous, because that makes mistakes.

http://www.subsim.com/radioroom/showthread.php?t=154461

Secondly, it also shows a better direction to move away from the listening location, more parallel to the target course (that way you are less likely to get too close and be detected). Do not go along the 4th (imaginary) bearing line as that will make the crossing with the 'real 4th' bearing line difficult to see.

And move fast! Surface the uboat and set speed to maximum. I measured up the distance you moved away from the listening location. It seemed to be just 1.4 km. In 9 minutes that would be only 5 knots. Did you do that when submerged? On the surface you could have gone 3 times as far in the same time. Also a longer listening time would have helped here alot. This cannot explain why the 4th bearings didn't cross, but would help to measure range and speed accurately.

Perhaps your sub has turned in the time when you were listening to him. Make sure you have 'rudder amidships' and engine off. Even when the uboat has a small speed speed the crew can make the uboat turn to try to steer to the waypoint mark. If that happends all those bearings are meaningless and you need to do it again. Set 'rudder amidship' and be at periscope depth (it is neccesary to hear him anyway) when you listen to him.

[bojan811]

Yes I was at the PD and I was moving ahead standard.
Because of that I traveled only a ~2km.

Did not acourd to me that I could be surficing the boat and go ahed flank to intercept the conacti.

I wached I looked the video you gave me.It`s refreshing and nicely made.Good resolution.It show how flexible the the time can be for mesuring the contcats beringlines.

Method is interesting too.Will try it, it can hurts.


I did`n not check my AoB because I was one manual t now . But I swear it keept teling me the contact is closing.
That I know for shure.

I used the program you gave me and I got the 84 angle of targets course.
Not 79 like in the game.

I eventualy managed to spot the ship.

Because he was going from 1 place to another while I was wrighting you the post, when I come back he was from 348 gone to 317 so I just marked bouth dots on the cyrcle and used the gained coruse.Put my cours line to intersept it and by accidentally I found the bloody ship.


"Btw. - why did you change your interface?"

I don`t understand the q on what interface do you mean. Maybe you mean because yesterday i insaled ACM mod for hitmans optic and jaged tools.
Is that what you meant?

[Mittelwaechter]

Hi Bojan,

that's what I meant.

Working on your training missions...


CU

[Pisces]

Originally Posted by bojan811

...
I did`n not check my AoB because I was one manual t now . But I swear it keept teling me the contact is closing.
That I know for shure.

...

I do not really trust my crew when they say this. Because they start saying 'constant range' when the AOB is between 60 and 120 degrees. True, the range to target changes only a little (about 15 % less) between those AOB but I find it a very rough estimate.

Secondly, I am not sure how the crew (game) determines that. Does it say that only based on the AOB? (which would be false and impossible to know) Or does it actually calculate if the target comes towards me based on both my and his speed and courses? (more credible, but not enough for the following reason) Anyway, I don't think the hydrophone operator could determine that so quickly in reallife. He would need a long period of time before he noticed a volume change, or even a frequency change (doppler effect). I have more confidence in what my measurements tell me.... in the end.

[bojan811]

Originally Posted by Mittelwaechter

Hi Bojan,

that's what I meant.

Working on your training missions...


CU

Cant wait to try them.Thaks man.