NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Air navigation bubble sextants
From: Gary LaPook
Date: 2026 Mar 17, 22:07 -0700
From: Gary LaPook
Date: 2026 Mar 17, 22:07 -0700
The current FAA flight navigator flight test requires that all celestial fixes be within 10 nm.
(37) Take celestial fixes at hourly intervals when conditions permit. The accuracy of these fixes shall be checked by means of a radio or visual fix whenever practicable. After allowing for the probable error of a radio or visual fix, a celestial fix under favorable conditions should plot within 10 miles of the actual position.
https://www.ecfr.gov/current/title-14/chapter-I/subchapter-D/part-63
My experience is that it is usually better than that.
In 2010 Frank and Greg took several in flight bubble sextant shots:
https://navlist.net/CN-aboard-Cessna-172-Rudzinski-jan-2010-g11467
