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Twelvefield · 08-03-05, 06:16 PM

As long as you can stay on the surface, but out of the detection range of the ship you are tracking, you can get range and bearing from your Weapons Officer, and use that info to calculate speed.

1) Put the WO up on the bridge, stop sub.
2) Click on WO's binocular icon, and he will give you range and bearing.
3) Use the ruler tool to plot the mark on your nav map.
4) Wait 3 minutes 15 seconds of in-game time (use TC if you like).
5) Repeat steps 1-3.
6) Use the ruler to make a line that connects your two plots. The length of that line in meters divided by 100 is your target's speed in knots, so that if the distance were 300m, the target is moving 3 kts/hr.

More advanced technique: Use Wazoo's nomograph:

a) If you know how far the target has travelled and you know how much time it took, then you can calculate speed.
b) Decide on a time interval of at least 1 minute.
c) At the beginning of that time, stop sub, plot range and distance of target.
d) Repeat step c at the end of the interval.
e) The nomograph has 3 lines: time, distance, speed. Use the marker to put X's on the time and distance used by the target.
f) Use the ruler to draw a line through the two X's that extends thru the speed line. Where the ruler line meets the speed line is the target's speed.

Both techniques assume you are surfaced. A yet more advanced technique involves being submerged. Again, you can use your WO to calculate range, and the bearing will be on your scope. Or, if you can use the stadimeter in the scope, you can bypass the WO, and get your own range. This gets really tricky if the weather is worsening. Be sure not to leave your scope above the water for any time more than absolutely neccesary to get your measurement. (One guide reccommends 5 seconds only!)

Lastly, another method you can try if all else fails is to run a course parallel to your target, and then match speeds that way. You can use your hydrophones to keep track of your target, which should be at around 90 or 270 degrees to you, and fiddle with the throttle until you match speeds. A few periscope checks during the process will help.

08-03-05, 06:16 PM	#6
Twelvefield Planesman Join Date: May 2005 Posts: 186 Downloads: 0 Uploads: 0	As long as you can stay on the surface, but out of the detection range of the ship you are tracking, you can get range and bearing from your Weapons Officer, and use that info to calculate speed. 1) Put the WO up on the bridge, stop sub. 2) Click on WO's binocular icon, and he will give you range and bearing. 3) Use the ruler tool to plot the mark on your nav map. 4) Wait 3 minutes 15 seconds of in-game time (use TC if you like). 5) Repeat steps 1-3. 6) Use the ruler to make a line that connects your two plots. The length of that line in meters divided by 100 is your target's speed in knots, so that if the distance were 300m, the target is moving 3 kts/hr. More advanced technique: Use Wazoo's nomograph: a) If you know how far the target has travelled and you know how much time it took, then you can calculate speed. b) Decide on a time interval of at least 1 minute. c) At the beginning of that time, stop sub, plot range and distance of target. d) Repeat step c at the end of the interval. e) The nomograph has 3 lines: time, distance, speed. Use the marker to put X's on the time and distance used by the target. f) Use the ruler to draw a line through the two X's that extends thru the speed line. Where the ruler line meets the speed line is the target's speed. Both techniques assume you are surfaced. A yet more advanced technique involves being submerged. Again, you can use your WO to calculate range, and the bearing will be on your scope. Or, if you can use the stadimeter in the scope, you can bypass the WO, and get your own range. This gets really tricky if the weather is worsening. Be sure not to leave your scope above the water for any time more than absolutely neccesary to get your measurement. (One guide reccommends 5 seconds only!) Lastly, another method you can try if all else fails is to run a course parallel to your target, and then match speeds that way. You can use your hydrophones to keep track of your target, which should be at around 90 or 270 degrees to you, and fiddle with the throttle until you match speeds. A few periscope checks during the process will help.