Need for what? I only said DR involves a known reference, you keep try to make
this about the precision of the technique. Everyone knows that a DR or an EP is
not the same as a FIX. Understanding the difference is a significant part of
navigation. But this subtlety seems to be lost on you.




"JAXAshby" wrote in message
...
no it's not, because you don't know how far it is from you.

besides, jeffies, *if* you knew physics well enough to get the degree you
claim
you would know you need *two* reference points, or one point and a distance.

ask your wife to explain it to you.

If that's the criterion, then the North Pole is a good reference point.


"JAXAshby" wrote in message
...
the starting point is no longer a reference point once you are moving,
because
you no longer know where it is in relation to where your boat is.

this ain't hard stuff, dood. every pilot on the planet knows it.

absolutely not. DR has no reference points in it, and I have never
stated
that
it does.

In that case, you best look up "reference point". The starting point of
a DR plot is generally at a known reference point and it can easily be
said that the ending point of your DR is also a reference point.

LOL Why is it, every time I open a Jax post now, my computer starts
playing the music from "Twilight Zone"?

otn