
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Bowditch 1995 Table 18
From: Doug Royer
Date: 2005 Feb 3, 10:20 -0800
From: Doug Royer
Date: 2005 Feb 3, 10:20 -0800
Relative bearings are ALWAYS taken from > the head in a counterclockwise(right to left,0 - 360)manner. Interesting. Yes,the way the above is written,that would be very interesting.My appologies.I'll start proof reading before sending to cut down on my mistakes.Clockwise is what I intended. Jim has quoted Bowditch. I looked at my 1984 edition of Bowditch last night and found the same discription as Jim and others. My Annapolis Book of Seamanship uses relative bearing similar to Bowditch, angle from the bow (or COG) aft on either side) 0 to 180. I wonder how one would communicate the above relative bearing data( 33 * relative my port/starboard side)? That format of relative bearings seems cumbersome to me. Chapman states, "Relative bearing is the direction of an object from the observer measured from the vessel's heading clockwise from 000 to 360. Dutton states: "Keep in mind that "angle on the bow is not the same thing as relative bearing. The former is measured from the bow in either direction as an angle. whereas relative bearings are measured clockwise from the bow through 360." In no case have I seen the 0-360 use of relative bearing in a counterclockwise direction (looking down from aloft). It has always been clockwise, same as a compass. You are correct.As stated....my appologies. No wonder my shipmates generally give directions to other craft as 1 o'clock, 9 o'clock etc. Much less confusing, unless of course they have a 24 hour watch.Bill Noyce also found a typo in one of my comsuption equations yesterday.As he pointed out: log C = (log c + 2/3 log W) - 2/3 log w. Not the way I wrote it.