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Trav_R · 11-05-05, 07:52 PM

If you're wanting to be able to plot hydrophone info on the map, there's a few ways to do it. You could just rely on the SO, but it's much funner to do it on your own, and it doesn't take much longer. Plus, once you get decent at it, you can guess the targets range a lot more accurately than "long" "medium" and "short" range like the SO does.

You first have to make sure the volume on the hydrophone is all the way up. Since you can't tell how high the volume is without actually having the mike pointed at a target, what I do is run my electric engines and point the mike at 180 so I can hear my own screws. Then you just click on the black knob by the wheel and drag it around until the sound is loudest. Once you've done that, your volume will stay at max until you reload the game, so you don't have to mess with it anymore. Of course, when you're actually listening for targets, you want to be at all stop.

Now what you do is be at periscope depth or lower, all stop, and make a full sweep listening for screws. Once you hear some, you can tell merchants from warships by their speed. Merchants have slower sounding screws, warships generally run much faster than merchant screws. So, once you find a target and you have the needle pointed in the direction where the sound is loudest, you have the bearing to the target, which is accurate to within 2 degrees or so. Now you have to guess the range, which is tough at first but you can get good at it before long.

For guessing range keep in mind that you can detect targets up to about 20km away, so if you can just barely hear the target, then it's probably about 18-20 km away. If it's about twice that loud, then it's around 10km, and if it's within visual range, find out its range with the periscope and then listen again so you know what targets sound like at that range. Now, you go to your nav map and plot a point. You'll need the bearing mod if you don't already have it.

http://venus.walagata.com/w/patricio...verlay_3.0.zip

Once you have that installed, zoom in on the map until you can see the bearing tool shows up. Draw a line from your sub to the target's bearing and at the estimated range. Put a mark there with the marker tool and write down on a piece of paper the mark number and the time that you put the mark there. Now you can delete the ruler line, just leave the mark there. If it's the first time you've heard that target, then you don't have any idea which way he is going so wait 5-10 minutes and plot another point to get an idea of his direction. Then surface and move roughly towards a position where you can intercept him, stopping every 10 minutes or so to plot a point.

After about 5-6 points, you should know his course to within about 5-10 degrees, and if you've been writing down the times, you can also get his speed to within about 2 knots. If your first mark was at 18:00 and your latest mark was taken at 18:45, draw a line from the first mark to the latest one. Let's say it's 14km. Divide 14 by .75 (3/4 of an hour) and you get 18.7 km/h. 1knot = 1.8 km/h, so now you divide 18.7 by 1.8 and you get 10.4 knots. All you need is a rough idea of his speed so that you can get in front of him with well enough time to get settled in and take more hydrophone readings by the time he reaches you, you don't need his exact speed.

Once you're in his path, point yourself at a perpendicular course and wait on him to cruise right into you. I've used this method in heavy fog before, and each time by the time the target was in visible range (about 400m) I already had the TDC manually set up for a perfect shot. I pointed the crosshairs and fired away without even bothering to adjust the TDC, and I hit every time. The hydrophone is definitely worth getting good at.

11-05-05, 07:52 PM	#10
Trav_R Ensign Join Date: Oct 2005 Location: Oklahoma, USA Posts: 227 Downloads: 0 Uploads: 0	If you're wanting to be able to plot hydrophone info on the map, there's a few ways to do it. You could just rely on the SO, but it's much funner to do it on your own, and it doesn't take much longer. Plus, once you get decent at it, you can guess the targets range a lot more accurately than "long" "medium" and "short" range like the SO does. You first have to make sure the volume on the hydrophone is all the way up. Since you can't tell how high the volume is without actually having the mike pointed at a target, what I do is run my electric engines and point the mike at 180 so I can hear my own screws. Then you just click on the black knob by the wheel and drag it around until the sound is loudest. Once you've done that, your volume will stay at max until you reload the game, so you don't have to mess with it anymore. Of course, when you're actually listening for targets, you want to be at all stop. Now what you do is be at periscope depth or lower, all stop, and make a full sweep listening for screws. Once you hear some, you can tell merchants from warships by their speed. Merchants have slower sounding screws, warships generally run much faster than merchant screws. So, once you find a target and you have the needle pointed in the direction where the sound is loudest, you have the bearing to the target, which is accurate to within 2 degrees or so. Now you have to guess the range, which is tough at first but you can get good at it before long. For guessing range keep in mind that you can detect targets up to about 20km away, so if you can just barely hear the target, then it's probably about 18-20 km away. If it's about twice that loud, then it's around 10km, and if it's within visual range, find out its range with the periscope and then listen again so you know what targets sound like at that range. Now, you go to your nav map and plot a point. You'll need the bearing mod if you don't already have it. http://venus.walagata.com/w/patricio...verlay_3.0.zip Once you have that installed, zoom in on the map until you can see the bearing tool shows up. Draw a line from your sub to the target's bearing and at the estimated range. Put a mark there with the marker tool and write down on a piece of paper the mark number and the time that you put the mark there. Now you can delete the ruler line, just leave the mark there. If it's the first time you've heard that target, then you don't have any idea which way he is going so wait 5-10 minutes and plot another point to get an idea of his direction. Then surface and move roughly towards a position where you can intercept him, stopping every 10 minutes or so to plot a point. After about 5-6 points, you should know his course to within about 5-10 degrees, and if you've been writing down the times, you can also get his speed to within about 2 knots. If your first mark was at 18:00 and your latest mark was taken at 18:45, draw a line from the first mark to the latest one. Let's say it's 14km. Divide 14 by .75 (3/4 of an hour) and you get 18.7 km/h. 1knot = 1.8 km/h, so now you divide 18.7 by 1.8 and you get 10.4 knots. All you need is a rough idea of his speed so that you can get in front of him with well enough time to get settled in and take more hydrophone readings by the time he reaches you, you don't need his exact speed. Once you're in his path, point yourself at a perpendicular course and wait on him to cruise right into you. I've used this method in heavy fog before, and each time by the time the target was in visible range (about 400m) I already had the TDC manually set up for a perfect shot. I pointed the crosshairs and fired away without even bothering to adjust the TDC, and I hit every time. The hydrophone is definitely worth getting good at.