Need help, hunting by hydrophone.

[wildcards]

I've not played for a long time and I seem to have misplaced my notes on how to get a "rough" indication of the targets ship it's heading, that I can plot on the map.

Did a couple of searches, but I keep tripping over guides/tutorials that involve using sound contact bearing and range. If I'm not mistaken, there was no option to accurately determin range at that time, could be mistaken, but my blurry memory recalls I only had the sound contact bearing to work with and my map tools and stopwatch.

I believe there is a more advance way to get a very pinpoint accurate course of the target ship, but this involved some fancy math and a good amount of map drawing, I don't believe I used that and used a more simpler cruder version. Any one able to guide me to a tutorial that uses hydrophone only and doesn't make use of range?

[ETsd4]

Originally Posted by wildcards

Any one able to guide me to a tutorial that uses hydrophone only and doesn't make use of range?

Type of ship:
(- BDU contact report - exact)
- hydrophone sound - exact

Speed of ship:
- rpm of the propeller - exact
- hydrophone-guy - not exact

Distance of the ship:
- width of loudest sound cone in degrees - exact
- hydrophone-guy - not exact

Course of ship:
(- BDU - not exact)
- using the speed- and distance-calculation above 2 times - exact


For further infos do a search for Canovaro's documents.

[Pisces]

It's probably not what you used, and is based on the math behind those advanced mapdrawing tutorials. But it is a no-brainer to get AOB (and from that course) of the target with it. Just slide those wheels. You need patience for it though. The time interval should be atleast as long as it takes for bearing 2 to move 5 degrees from bearing 1. Longer makes the AOB more accurate.

AOB at bearing 3 is: the AOB in the readout window and add B3-B1 to it.

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

[wildcards]

Thanks so far,

@ETsd4
I did some searching for Canovaro documents and found it interesting to read that by just listening to the engine noise, the speed could be determined.

I've not yet tried it, but I'm very sure I don't got the patience for this and has large room for human error, me getting it wrong



@Pisces
I recall having stumbled on this before and tried it out, but had some difficulties using it. I'll have another look at it and try to use it.

Quickly read through it and the "3 bearing" keeps gnawing at me, it sounds familiar in some way. I've a gut feeling I took 3 bearings over a period of time with the hydrophone and marking it on the map and based on those three bearings I drew on the map, I was able to calculate a heading, but not exactly sure how. The only thing I really remember and am very certain off is that it was extremely simple to do and no complex math was involved.

I've found some posts, with more reading material, hopefully I'll cross paths with the method that I used. But if anyone has an idea of what possible method I'm talking about and can redirect me to a guide, that would be great.

thanks in advance.

[Pisces]

Originally Posted by wildcards

...

Quickly read through it and the "3 bearing" keeps gnawing at me, it sounds familiar in some way. I've a gut feeling I took 3 bearings over a period of time with the hydrophone and marking it on the map and based on those three bearings I drew on the map, I was able to calculate a heading, but not exactly sure how. The only thing I really remember and am very certain off is that it was extremely simple to do and no complex math was involved.
...

It is possible to get a range, speed and course fix from 3 bearings, IF you move quickly enough on the surface (so your spots are far enough apart), and make a significant turn or speed change after the 2nd bearing. Ofcourse with the same time between the bearings. You'll get 3 bearing lines from 3 different spots on the map. Then by using the circle tool you can try different arrow sizes and directions to find 3 points along the 3 bearing lines. If it is right, the points are displaced by the same distance (hence we need the circle tool, i.e. centered along bearing 2) and along the same (course) line. BUT, finding this solution is very tricksy, as it requires alot of trial-and-error. One could argue that this is easy and simple requiring no complex math. But it certainly is arduous in my mind. Just not my cup of tea, I like a more systematic approach.

BTW, would that method have been described in the SH5 forum only, or in SH4 or SH3 section?

[wildcards]

@Pisces

It's highly possible, I took it with me from SH3 or SH4, I truly have no idea what I exactly did. I'm not 100% sure I took 3 bearings, could have been more.

I stumbled on top of "How to use the 4 bearing method in SH5" by stoianm. This could very well be what I've been using, but I'm having trouble applying it, there is little to no math involved and it all comes down to making good use of the map tools.

Either the ships I've been tracking had a course correction some were along the way or I'm still doing something wrong, for I get the feeling I'm not doing it right. The only ships I've found so far have been blind luck.

I'm making use of Real Navigation and I don't know how much this might mess things up and how far of course my navigator calculates me to be from my true location.

So far, I'm still early in the war and only able to track and chase down slow and with some difficulty medium speed moving ships.
Don't even know if the skills of my crew come in to play when I'm applying this 4 bearing method...

Will keep on trying, this 4 bearing method for many things feel familiar to me, even though I can't get it to quite work yet

[Pisces]

Getting those bearings drawn in the right direction is critical with this method that Stoianm shows in his videos. Every thing in the end depends on it. Personally I find that the compass read-out (Uboat course) of the UI is too crude. I want to see more clear individual marks on it to make sure what direction the boat is pointing.

I don't know to what extent the RealNav mod can distort your results. I don't have the game. But I'm sure in reality this (keeping track of uboat speed changes, and distance moved by it) was an important issue as well.

[Trevally.]

If you use TDWs UI - you could try my tutorials. There is one for the four bearings and it will take you through the process step by step in game