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Re: A-10 Sextant Manual
From: Christian Scheele
Date: 2009 Jun 12, 12:28 +0200
From: Christian Scheele
Date: 2009 Jun 12, 12:28 +0200
I just a had look at two of the webpages pertaining to AFM 51-40 (1973) that you referred me too. It really looks helpful... I'll definitely visit your very useful website soon to read up on the things we discussed. I guess I'm a bit out of my depth at this moment, but I'll say this anyway. You explain clearly how Chichester made use of the LOP through destination to find his way. On the azimuth problem, caused by the the moving sun: At the moment I am thinking that azimuth is just the flipside of the LOP - I am specifically thinking of gradient, bearing of the latter - and vice versa, because azimuth and LOP are perpendicular to each other. One can only change as much as the other. But I have yet to read the material you attached to your messages and the bulk of the readings on your website. I'll do that soon. Many thanks for the advice! Christian Scheele ----- Original Message ----- From: "Gary LaPook"To: Sent: Friday, June 12, 2009 10:14 AM Subject: [NavList 8635] Re: A-10 Sextant Manual > > The bigger problem is that the azimuth of the sun changes as it moves > across the sky, not that the LOP is slightly curved. Look at Weems > writings on this at > > http://www.geocities.com/fredienoonan/landfall.html > > Chichester describes the same procedure in the Observers' Book. > > The problem of shifting LOPs and curved LOPs is handled by using the > destination as the AP and this was the method being used by Chichester. > Done this way, as long he manovered the plane to keep reading the same > altitude from his sextant as that which would be measured at the same > instant of time at the destination, then he can be sure he is staying on > the LOP through destination, whatever the azimuth happens to be. > Chichester did this and took an additional sight to confirm that he was > staying on the LOP to Lord Howe. > > gl > --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---