Quote:
Originally Posted by flag4
i really love these short concise methods. ive just printed it off for keeps. cheers brock 
could some one clarify for me the need for the 3 minutes & 15 second timing? does it have to be this or could it just as well be 5 minutes or 4. aslong as the time between counts is the same, what difference does this make - especially the 15 second thing? |
The distance in meters that a ship travels in 3:15 is easily converted to knots by dividing by 100: If a ship travels 700 meters in that time, its speed is 7 knots.
It's a handy shortcut to find the speed of a target.