A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brian Walton
Date: 2015 Nov 24, 14:53 -0800
Box or Normal Sextant
You point out that FC used the word "dismantled" when stowing his sextant, in your book. Thank you. In my later book, the same incident is termed "closed". Dismantled is rather a strong word for putting the lid back on a box sextant, although it might be suitable for either type if it involved taking a telescope out of its collar to get it in its stowage. To bolster Geoffrey's strong argument that FC used a box, I grabbed a box sextant and flew it yesterday.
Ground temperatures got below freezing yesterday, and air temperature reduces by 3 degrees every 1,000 ft. Add in a 90 mph wind and chill factor and gloves are necessary. My antique box sextant, which has 3 shades, and meets Geoffrey's definition of a marine box, although it is vulnerable to salt water, needs strong thumb nails to open the shades, so with gloves, that was out. Like FC, I can only take what I've got. I took the Barker in the photo.
I find it is all but impossible to set the Barker's vernier scale, using it's built-in magnifying glass, with one hand on the stick. It also takes longer to line up a vernier, than a micrometer screw. I was in danger of breaking my 5" and "one hand on the stick" rule. To add to the ambiguity in FC's book, the "box" of the Barker is actually part of the leather case! Thank you both anyway for keeping me straight. I still prefer the Freiberger for actual sighting.
i might add that the Barker is about 4 times the bulk of my antique box, and although it has a strap, it must be taken off the neck and stowed behind the stringers before aerobatics (yes) and a 3 point landing can be attempted to avoid stick fouling.
Of all the manoeuvres done on FC's trips, the trickiest is 3 pointing a biplane with no forward view on a narrow strip, a right of passage all pilots went through then.