A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2016 Dec 24, 04:13 -0800
Living inland, I’ve long felt that the best sextant for me is an aircraft sextant. Without costly renovation, most of the handhelds are now too murky to look through to give much of a view. Periscopic sextants are younger and usually easier to see though. The advantages are you can use them anywhere (but afloat and making way) without the need for an external artificial horizon. You can even use them from indoors with a suitable hole to poke them through. The disadvantages are reduced accuracy, but in a static situation you can get down towards one minute of arc, and I suspect the intricacies of using an external AH don’t allow much better than this. With US models you also need 28V, but with European models you only need 3V, which is much easier to provide from batteries. The main problem is finding or making a suitable mounting. The mountings seem to be about ten times harder to find than the sextants.
At last it’s all come together. I’ve had Smiths periscopic sextants for over 10 years, and I’ve had an ex-Dominie mounting for them for almost as long. In the last year, I’ve obtained what looks like a ‘new and unissued’ ex-Bundswehr 3Volt Kollsman circa 1980 from a government surplus store in Poland for less than £100GB and what looks like a never used spare 3V mounting for the now retired RAF Nimrod Fleet, also for less than £100GB.
Not wishing to complete major modification to my house or sheds, the problem was where to place the mountings. I decided the ideal would be a small flat roofed caravan with two rooflites if I could find one for less than £500GBP. This would mean I could also tow it to areas of low light pollution and take it to shows. It would also make a useful ‘den’ for celestial activities. Eventually, I found one which had spent most its 35 years sitting in a field in Cornwall. The inside is like new, but the unworn tyres were seriously UV cracked; the brake cables were rusted causing the brakes to bind on; and the external parts of the gas fire had rusted away (the internals of the gas fire also contained a mouse or rat’s nest complete with a hoard of farmer’s red dyed grain) . After washing off the green stuff, replacing the tyres and the brake cables and rebuilding the gas fire, she’s now ready for use (photos below, (the Kollsman in the photo is a 24V USAF one)), so hopefully lots of celestial fun to come. DaveP