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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Index arm angle for Artificial Horizon sights
From: Chuck Varney
Date: 2023 Apr 19, 10:50 -0700
From: Chuck Varney
Date: 2023 Apr 19, 10:50 -0700
Frank,
You posed a series of questions beginning with "Am I imagining that constancy [of index arm angle relative to vertical], or am I right?"
No, you're not imagining the constancy--and you are correct.
I have attached a diagram that I did in 2016 showing how your observation has been put to use in the past--by fixing a rotatable spirit level to the index arm.
I have also attached one of the sources I found in 2016: page 554 from "Wrinkles in Practical Navigation (Lecky 1918)".
Chuck Varney
File:
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File:
-_spirit_level_on_index_arm_p554_marked.jpg.thumb.jpg "Click to enlarge.")
-_spirit_level_on_index_arm_p554_marked.jpg "Click to enlarge.")
