NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Daytime Venus Rising Dip Short
From: Gary LaPook
Date: 2012 May 6, 02:11 -0700
From: Gary LaPook
Date: 2012 May 6, 02:11 -0700
They are only in the Kollsman instruments. They don't actually cross, there is a gap in the center. I believe that they are there to help you keep the bubble near the center for most accurate sights. In the periscopic instrument that fits in a mount, the vertical line allows you to aim the sextant at the pre-computed azimuth so that you can find the desired body, the navigators field of view is limited to what he can see through the sextant, no windows. this also allows him to measure azimuths and check the deviation of the compass while in flight. See this picture that i posted a couple of years ago. http://fer3.com/arc/img/114221.img_6428.jpg http://fer3.com/arc/m2.aspx/Kollsman-periscopic-sextant-mount-LaPook-oct-2010-g14221 gl --- On Sun, 5/6/12, Geoffrey Kolbe <geoffreykolbe@compuserve.com> wrote:
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