NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Pub.229 GC-Calculation distance and course.
From: John Karl
Date: 2009 Dec 2, 10:47 -0800
From: John Karl
Date: 2009 Dec 2, 10:47 -0800
> As I read it, what Guus seems to be asking is how they got the > additional .2' �they added to the course from the AP (246.1�) to the > course from the actual point of departure in Fremantle (246.3�). > > Hewitt Yep, I think you're right. I hadn't paid any attention to parts (4) to (6) below the example. Part (6) requires a triple interpolation of Z among dec, LHA, and lat. I skipped the lat interpolation because the 32*03' departure lat is so close to 32*. Then my double interpolation of Z for LHA and dec gives me 66.25* rounding to the 66.3* on page XXI of H.O. 229. All this is pretty darn academic compared to actual practice at sea -- at least in my experience. JK -- NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList+@fer3.com
