NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: How accurate are fixes in practice?
From: Andrés Ruiz
Date: 2008 Jul 14, 10:11 +0200
From: Andrés Ruiz
Date: 2008 Jul 14, 10:11 +0200
I am writing an article about Position at LAN, and the real example will appear in it. But now I like to spend the little free time I have sailing, after some days cleaning and painting the hull with antifouling. A few weeks ago, sailing for four days I could not make any shoot, neither day nor night. The sky was completely covered. What is acceptable for me? What is the purpose of calculate our position? Knowing where you are, or better, knowing where you are not. Ashore I am able to fit my position inside a circle of 2.5 nm of radius, 2/3 of the shoots inside a circle of 1 nm. Aboard a sailboat, a small one, 8 m length, the things go worse: 7, 8 and also 10 nm. But in some circumstances, the fix could be acceptable, depending where the coast or shallows are. See the two charts with real fixes, one a celestial fix, (acceptable but dist GPS, Fix = 6.9 nm ), and the other more accurate, a coastal 3 bearing fix, position inside the triangle. Andrés -----Mensaje original----- De: NavList@fer3.com [mailto:NavList@fer3.com] En nombre de George Huxtable Enviado el: viernes, 11 de julio de 2008 17:32 Para: NavList@fer3.com Asunto: [NavList 5798] Re: Noon sight for longitude ... Andres Ruiz wrote- "Also I try this method aboard a sailboat and the results are acceptable due to the waves and roll and pitch" That's intriguing. It would be interesting to see the numbers he came up with, in real-life; and what he considered acceptable. ... --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---