NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: DR vs EP vs MPP vs Fix vs Running fix
From: Yves Arrouye
Date: 2002 Feb 10, 11:52 -0800
From: Yves Arrouye
Date: 2002 Feb 10, 11:52 -0800
> Yes, from the log book and the DR, one ought to be able to reconstruct the > actions of the vessel, i.e. course steered and speed run (through the > water). > The actions of the vessel, not the actions of the wind and current, are > what > determine liability in court. Looking at it from the positive side, if you > can > prove that your actions were correct, you have a better chance of being > exonerated from liability for damages. To reconstruct the position at a > given > time, one would need to factor in current. And I hope that these would also be taken into account to determine whether your actions were correct or not. Yes you're right that you need the DR to determine the true set and current. What we do is I guess just the opposite of your way: plot the EP (so we can see on a chart where we think we are) and use the notes from the log book to make smaller plots, off the chart, to determine such things as set and drift between two fixes. YA