"Dave" wrote in message
...
On Wed, 3 Dec 2008 15:29:13 -0700, "Charles Momsen"

said:

What 4 word term is used to describe the method used to determine if a
vessel is on collision course with yours?

Steady bearing decreasing range.

That's about as basic as you can get.

Correct, though I was thinking of CBDR. Constant bearing decreasing range.