RuB1.4 - but dont know what the scales on right mean on nav

[sdcruz]

map

I have three like rules on the RHS of the nav map (F5)
-knots
-Kms
-Minutes

What do these do/mean?

How can i use these in general?

Thanks
Shelton.

[bobo]

It's if you have any 2 of the combination you can draw a line using the ruler tool to find the 3rd variable. If your plotting a contact(s) on the map the rule of thumb (at least when I was in the USN) is every contacts track gets updated every 3 minutes. What this means is you get a bearing and distance to the contact either via the periscope or you can use the Ast Plotting features that are now included in RUB. Once you have consistent plot of every 3 minutes you can calculate the course and speed of the contact. So, you make an initial mark on the contact, 3 mins later you make a second mark. Measure the distance between the two with the ruler tool. Using that distance measurement play connect the dots by lining up the 3min mark with the distance mark and this line will give you the speed of the contact. Also, the longer you mark a contact the more accurate your calculations will be provided that you keep in time and not got get sloppy with the plots.

Hope i didnt confuse ya to much.