A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Mark Coady
Date: 2015 Dec 8, 10:09 -0800
After reading the reccomended "Self Contained Celestial Navigation with HO 208" and working through a number of sight reductions with HO208, I was intrigued enough to try to hunt up a copy of the table itself for use without abusing my book. I found the simple explanation good for my simple mind, and the solutions straightforward and understandable.
Failing to find a .pdf on the first attempts, I managed to find a beautiful conditon US Navy Department Copy for my library. It is wonderfully compact. (of course now I can't use that, its an heirloom from 1935 LOL.)
I kind of fell in love with its austere cookbook simplicity as an emergency and practice backup with just a pencil. I first learned on HO 229 in print version, and pdf's of HO 249, with its good points....
It set me to thinking why I ignored the compact tables in the NA (i always figured I could learn them quickly in a pinch), which is a similar idea of breakdown into two triangeles.
In trying to research it, the NA tables have a stated accuracy to 1' of angle, which may increase to 2' with rounding errors. HO 208 the statement I have found is a few tenths of minutes.
Ho 229 i supposed to be .1, but my understanding from real life calcs is its more like .2 to .3, creeping it closer to the very popular 249.
Obviosly I am picking over jellybeans, as any of them can get the sailor home. I was just curious if anyone knows the verified computational accuracy of HO 208 vs the NA tables, and has anyone else found the compact simplicity refreshing as an alternate method for occasional use. (heck the whole thing fits in my waterproof sextant box) (makes me wonder about 214, which I have never used)
I think the real story is I found the explanations so clear and concise , thereby really increasing comfort, as I got right answers out of the chute first time without any futzing whatsoever.
I love the thought of something that makes finding right answers cookbook, even when cold, tired, and stupid, and everything else seems to going wrong.