NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brian Walton
Date: 2015 Nov 22, 06:58 -0800
Type of Sextant
Hello Geoffrey,
I was aware of Hughes' work, and his description, which is a verbatim copy of FC's. That is why I used quotation marks. There is nothing wrong with a box sextant, and as I described in my post, I used 2 different boxes in the biplane. They were particularly good whilst I was finding out how low one has to fly, and were small enough to allow sights around the starboard beam. Quite acceptable.
I, like FC, was trying out various sextants in a biplane. FC told the authorities at Aukland that he would use a "normal" sextant. He records returning it to its case, together with other nav instruments, and that it flew about when he hit turbulence. He used a neck lanyard when sighting.
The ambiguity is; does box refer to the sextant, or the case, and, does case mean a normal wooden box, or a leather pouch? Marine and type mean nothing. I have never seen a box sextant in a wooden box, nor a leather box sextant case big enough to hold protractors. FC did not describe unscrewing the box sextant to fix the cover as a handle, tedious, and I have never seen a box sextant which could accept a neck lanyard without threading string through the works. Any with a telescope would poke your eye out. His manipulation of shades etc could apply to any type of sextant. In any case (!) I don't think the type of sextant is relevant to the main theme: using a Bygrave solo, and taking solo sextant readings to fly a Landfall procedure in a solo biplane. I proceeded with a Frieberger because of the UK winter conditions, and the pilot's safety. I was not prepared to use 2 hands on the sextant below 500ft, nor look at any one instrument for more than 5".
I am a fan of box sextants. If you go back to last spring, you may find a post and image of a trip I did then. That box has been everywhere with me for 25 years. It was, I think given to missionary David Livingstone's father-in-law, in about 1840.
I thought it fun to fly a 70 year old biplane, and use a 170 year old sextant, to investigate FC's 85 year old theories.
Regards
Brian Walton