Contact position by hydrophone

[Canovaro]

In my experience with GWX, It seems that when you are on time compression (or not), and the hydro guy finds a contact, it's always somewhere around 23.8 - 24 km away.

In bad whether it is more around 18 km.

Good to get that first observation point when you like making "fast 90's". Thought I'd let you know.

What's your experience?

[Chisum]

It seems correct.
But sometime I hear it before the crew, about 25 km maybe little more.
It's simple: when I'm in x2048 if the clock stop a short moment it means something big is near me.
Sometime it's just a dolphin but often it's a ship.

That's just because I have not enough memory, only 1Gb.
With 4 Gb I'm sure the clock never stop.
;)

[Contact]

I remember when on my first patrol in 1939 when hydrophone guy picked up a contact lets say it was approaching from bearing 300 on hydrophones, but on periscope the target was at 310-312 degrees. This innacuracy gone when I placed newer hydrophones :yep:

[KeptinCranky]

The hydrophones when manned by crew generally pick targets between 20 and 25 km, a little less at high TC.
I can also say that even with a enormously powerful computer you still get the stutter when there's ships in the area at high TC, I stay at 256x max when not in transit.

I've found that convoys and some ships (mostly turbine powered warships) can be heard at about 35km out, it's tough to judge their heading though since there will be no report on those from your hydrophone operator.

[Pisces]

How do you determine that range? Also, what Tc settings are you using?

Personally, I stay on the move, and periodically dive to listen (2 hours in good weather, 1 hour in bad). So the contact can be anywhere when I hear him.

But learned from messing around with the mission editor that contacts become audible on hydro when they enter about 32-34 km range. So if you have set to a TC of 2048, and a contact doing 6 knots (low speed: 3.09m/s or 6.3km in 2048 'accelerated seconds') this could match your values if you reacted within a second or so.

[Pisces]

..., it's tough to judge their heading though since there will be no report on those from your hydrophone operator.;) http://www.subsim.com/radioroom/showthread.php?p=875260#post875260

[UnderseaLcpl]

Yep, hydrophones are your best friend. I patrol shipping routes by spending as much time as possible underwater at slow speed, listening.

I wonder why they seem to have such a short range in "Das Boot".

[Jimbuna]

Try marking the tip or extreme of the contact line with the pencil then up the tc to x8. Plot a few more of the extremities and you'll soon get a rough idea of the vessels heading.

For a real rough guesstimate of the range, try measuring the length of the contact line.

[KeptinCranky]

Yes, all of the above is fine, IF you get a line... :D

but with convoys that are say 35km out you don't get a line, you only get that when the sonarman finally decides that the ship you've been tracking for an hour is an actual honest-to-god contact
otherwise it's just a bearing and your best guess at the distance from what you can hear yourself.

if you start working with those lines and extend them to 35km the margin of error becomes fairly large :-?

nevertheless, listening for contacts yourself is fun and useful :ping: