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Re: Position from crossing two circles : was [NAV-L] Reality check
From: Herbert Prinz
Date: 2006 Jun 8, 12:29 -0400
From: Herbert Prinz
Date: 2006 Jun 8, 12:29 -0400
Michael Dorl wrote: > Since one has a good idea of the course and speed between any two > observations, > it seems to me the problem is to determine points on the equal altitude > circles separated by that vector. Right. And this has to be done point for point along the circle, not by just moving its center by that vector. The "circle" isn't a circle on a mercator projection to start with and changes its shape when being moved north or south. Said vector translates to different delta longitude at different latitudes, so by how much do you shift the GP of the star? You know this only after you have the latitude of your fix. > I saw some variant of the Bowditch treatment with the reference to Dozier > but the one I saw was very sketchy and incomplete. I never did find > anything by > Dozier. Dozier's method is described in Bowditch 1984, p.617. Herbert Prinz
