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Arclight · 06-13-08, 07:16 AM

But what if he hasn't got surface radar yet, like me? Or the target is beyond visual range, ruling out the stadimeter? I'll just go ahead and give you a method I use and find very simple;

No use in pinging on long ranges, the dial on the sonar station only goes to 5000 yards. You'll still get a return if you wait long enough, but the limit on the dial might be an indication that it's not ment for those ditances. Requesting a range from your sonar guy is wildly inaccurate (in fact, I find he only gets it right when you already made a reasonable entry yourself).

Like mentioned above, have a look at the map and place marks on the end of the sonar bearing line every minute or so (You can also use the distance between these marks to calculate his speed

). If you observe for ten minutes, you'll have ten marks, in a more or less straight line.
Take out a protractor and click some distance away from your marks (be zoomed in as far as you can while still seeing all marks), place the second point on or near your first mark and draw the leg along your marks. Note the angle indicated and zoom out so you can also see your boat on the map allowing you to plot an intercept. Now extend the leg of the protractor running along the marks while keeping the angle the same.
Take a ruler, place the start on your targets last known position and measure off along the extended leg.
Take out another ruler, place the start on your boat and have it cross the extended leg. Now try to get the distances to match up on the crossing point (the further you zoom in, the more marks will apper on the ruler lines); if the distance from your boat to that point is the same as the distance from your target to that point, it would take the both of you the same amount of time at the same speed to get there. By travelling faster then your target you should get there first. You could also head for a position a couple of miles further along your targets course to make sure you get there first and stay outside visual range while doing it.

I also use this method, which is slightly more complex but probably more accurate:
http://www.subsim.com/radioroom/showthread.php?t=88961

If you find yourself behind your target and playing catchup, estimate his course and steer a course paralel to his while staying outside visual range. When your at an AOB of 45deg. (bearing 135 or 225), turn in 90deg. and move in to intercept his course.

Probably overdid it since you only needed a range, but I prefer to paint the whole picture. Makes it a whole lot clearer. Hope it helpes.

06-13-08, 07:16 AM	#8
Arclight Navy Seal Join Date: Jun 2008 Location: Land of windmills, tulips, wooden shoes and cheese. Lots of cheese. Posts: 8,467 Downloads: 53 Uploads: 10	But what if he hasn't got surface radar yet, like me? Or the target is beyond visual range, ruling out the stadimeter? I'll just go ahead and give you a method I use and find very simple; No use in pinging on long ranges, the dial on the sonar station only goes to 5000 yards. You'll still get a return if you wait long enough, but the limit on the dial might be an indication that it's not ment for those ditances. Requesting a range from your sonar guy is wildly inaccurate (in fact, I find he only gets it right when you already made a reasonable entry yourself). Like mentioned above, have a look at the map and place marks on the end of the sonar bearing line every minute or so (You can also use the distance between these marks to calculate his speed ). If you observe for ten minutes, you'll have ten marks, in a more or less straight line. Take out a protractor and click some distance away from your marks (be zoomed in as far as you can while still seeing all marks), place the second point on or near your first mark and draw the leg along your marks. Note the angle indicated and zoom out so you can also see your boat on the map allowing you to plot an intercept. Now extend the leg of the protractor running along the marks while keeping the angle the same. Take a ruler, place the start on your targets last known position and measure off along the extended leg. Take out another ruler, place the start on your boat and have it cross the extended leg. Now try to get the distances to match up on the crossing point (the further you zoom in, the more marks will apper on the ruler lines); if the distance from your boat to that point is the same as the distance from your target to that point, it would take the both of you the same amount of time at the same speed to get there. By travelling faster then your target you should get there first. You could also head for a position a couple of miles further along your targets course to make sure you get there first and stay outside visual range while doing it. I also use this method, which is slightly more complex but probably more accurate: http://www.subsim.com/radioroom/showthread.php?t=88961 If you find yourself behind your target and playing catchup, estimate his course and steer a course paralel to his while staying outside visual range. When your at an AOB of 45deg. (bearing 135 or 225), turn in 90deg. and move in to intercept his course. Probably overdid it since you only needed a range, but I prefer to paint the whole picture. Makes it a whole lot clearer. Hope it helpes. __________________ Contritium praecedit superbia.