NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Nasr
From: Hewitt Schlereth
Date: 2009 Mar 23, 09:19 -0400
From: Hewitt Schlereth
Date: 2009 Mar 23, 09:19 -0400
What the NA method does is break the Navigational Triangle into two right spherical triangles. The first time you enter the table you put in known factors (Lat and LHA) to get the unknowns in one right triangle. Then use those now-knowns to solve for what you want (Hc and Z) which are in the second. It helps a lot to have a sketch of the triangle to look at. This lets you see what parts of the triangles the letters (A, B, F, etc.) refer to. If you can, get a hold of Ageton (HO 214). The figure there is the one you want. Ageton uses different labels than the NA does, but if you read (patiently) paragraph 2 (Form of Tables) on page 284 of the almanac, you can re-label the figure and see how it works. Hewitt On 3/23/09, Yanni Nikopouloswrote: > > Hello George, I would love to have a copy of those pages. > Thanks > TURBO!!!!!cause bottles are for babies and superchargers blow!!! > Which would you rather have, go fast goodies or shiny shoes? > Your feet may look good, but if your engine blows up, you ain't going > anywhere. > > Yanni Marinated > S/V Princess Thalia > Columbia 8.7 #73 > On the Hard > Mayo MD > > > ________________________________ > From: George Huxtable > To: NavList@fer3.com > Sent: Monday, March 23, 2009 5:39:28 AM > Subject: [NavList 7728] Re: NASR > > > Guy Schwartz asked- > > | I know how to reduce a sight using the Nautical Almanac Sight Reduction > | method, however I don't > | > | Understand what I am doing aside from following the recipe. > | > | Can anyone give me a easy to understand description of what each step is > | doing. > > =================== > > I think I have the answer to Guy's question. It's a paper in two parts, 7 A4 > pages in all, which appeared in the spring and summer issues of "Navigator's > Newsletter", by P M Janiszek, who, as I understand it, was responsible for > these tables. I think, after reading those pages, Gay will feel that he > knows all that needs to be known about those tables, and perhaps a bit more. > > I have sent scans of those pages backstage to Guy, but won't publish them to > Navlist as they are copyright to the Newsletter. If anyone else would like > to refer to a copy, I'm happy to share; just ask. > > George. > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---