NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Azimuth Formula Questions
From: Doug Royer
Date: 2005 Nov 1, 15:23 -0800
From: Doug Royer
Date: 2005 Nov 1, 15:23 -0800
Doug Royer wrote: > I learned and then started to use HO-211 on a regular basis. 28 pages of > data covers just about everything to reduce sights. But that is all it is > capable of doing. It can't compute GC sailings etc Bill Noyce wrote: I'm confused. HO-211 should be able to compute GC sailings, sight predictions, and star identification just as well as HO-229 (though just like sight reduction, it takes more steps). For GC sailings, you of course use longitude difference as the LHA, and 60*(90d-Hc) is the resulting distance. For star identification, the trick is to use observed azimuth as the LHA, and observed altitude as the declination; the resulting Hc and Z are then the star's declination and LHA, respectively. (I've probably fumbled this a bit, but doing this with HO211 is fundamentally the same as doing it with the tabular methods.) -- Bill I never thought of it like that. Perhaps(most likely)you're correct. I'm not a great thinker when it comes to navigation theory/methods. I'd rather do it than sit around and think about it. So if something(procedure or extra method of using something)isn't written or I don't see it explained I don't waste time thinking how something can be used for a different application than what it was designed. I am definitely going to check what you explained concerning using HO-211 out directly to see if it feasible using your explaination. An extra use for an already very useful 28 pages. Thanks for bringing it to my, and anyone who didn't know, attention.