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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Bubble sextant collimation
From: Andrés Ruiz
Date: 2015 May 20, 16:07 +0200
From: Andrés Ruiz
Date: 2015 May 20, 16:07 +0200
In general, the available literature on bubble aircraft sextants avoids the observation of the limb of the Sun or Moon; the semidiameter correction. Handbooks of bubble sextants like A-5, A-7, A-12, and general documents like AFPAM11-216, AFM 51-40 (ED082051), also http://home.earthlink.net/~s543t-24dst/airnav/index.html
Talking about collimation — the correct alignment of the images of the bubble of a sextant and the object being observed —, with my A-12 using the technique described in "Bubble sextant collimation.pdf" I obtain very good results when the center or the UL/LL is observed, immediately checked with:
I will be pleased hearing other points of view, other techniques for UL or LL observations (SD).
Best regards,
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