Is there a tutorial for map plotting the targets speed?

[nx02nx02]

Im hoping for a tutorial or more information on exactly how to calculate the targets speed on the map by using distance and bearing. I do have the 360 bearing mod for the subs.

Another problem im having with doing this is the ruler in silent hunter 4 isn't detailed enough unless im doing something wrong. Am I doing this wrong? The ruler only measures in tenths of a degree. 0.1 nm, 0.2 nm, 0.3 nm etc.
How can I get an accurate measurement with that ruler? Is there a mod for a ruler that measures in feet or yards or meters?

Im really knew to this, perhaps there is a way to do it with a nm ruler.

Thanks for any info. :)

[nattydread]

Take a bearing and distance of a ship and start timing. Go to the map and use the protractor to draw a line out at the correct angle/bearing etc. Then use the ruler to draw out the correct range on the protractor line you made before. Mark the correct distance with your pencil. After 30 secs or 1 min or 2 mins, take another bearing and range. Draw it out like the first sighting and mark it. Now use the ruler to measure the distance between both marks. Now you have time and distance info. Speed= distance/time. If you use a 30sec block, multiply the distance measured by 120 and then convert for kts. If you used 1 min, multiply by 60 then convert to kts and if you used 2mins multiply by 30 then convert to kts.

It wont be totally perfect, it will give you a very good estimate. You can do this anytime because the movement of the sub doesnt affect things much...though the faster the sub is going and the longer it takes for you to draw everything out the more it will be off. So what you do is mark the subs location at the time of taking the sightings(so submovement is irrelvant) and take your time drawing overything out from that mark. Then rinse and repeat the next sighting.

[nx02nx02]

Will give it a try. Thanks for the info.