NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Fwd: Sextant accuracies
From: Peter Fogg
Date: 2003 Mar 18, 13:13 +1100
From: Peter Fogg
Date: 2003 Mar 18, 13:13 +1100
Thanks for this > From: "Royer, Doug"> In coastal pilotting these are known as Horizontal distance > bearings.Pick 2 > or more terrestial objects.Turn the sextant on it's side and take the > angles > between the 2 or 3 objects by superimposing one of the objects over > one of > the remaining objects.Dip is not a consideration in taking Horizontal > angles. Write the angles down and go to the chart.With dividers find > the > distances between each of the objects. So far so good > Your position will be tangental to the > distance between the objects. Hmm. Looked up 'tangent' in the dictionary which says 'touching esp. of a straight line in relation to a curve' which is all a bit baffling. Calculate the distance off, using dividers from > each point draw in the radius and where the lines intersect is your > position. > Just to see if I've got this (un)clear. We end up with part of the circumference of a circle, the circular LOP, which runs through the 2 objects?