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I know a number of our group have been looking for this rare mount.  https://www.ebay.com/itm/WW2-USAF-Kollsman-Square-D-Aircraft-Sextant-Periscopic-Type-D-1-W-Orig-Mount/332626950259?hash=item4d721c7873:g:fz8AAOSwAzJa2beU

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Well spotted Gary.  However, prospective purchasers should treat this sale with care.  Look at the sellers other items for sale.   From what’s offered, the chances are he/she knows little about aircraft sextants.  It’s not WW2 because it’s marked USAF, so it can’t have been ordered before Sep47.  However, the wooden case, as opposed to fibreglass and aluminium suggests it is late 40s or 1950s.  The statement W/Original Mount is meaningless.  The mounts were part of the aircraft; the sextants were either carried out to the aircraft by the crew, or if permanently stored in the aircraft, were swapped regularly for servicing.  Moreover, the mount has sockets for aircraft power in and sextant power out at what voltage we know not, whereas the sextant appears to be meant for torch power which is more likely 3-4.5V.  In fact, the mount is only the bottom half of the mounting; there’s an extra bit, which joins the top of the bit shown to the aircraft skin.  The top bit contains the shutter which seals the cabin when the sextant is removed.  The bottom half joins onto the top half with just four screws.  The missing top part joins onto the fuselage skin with 24 screws.  My photograph below shows a slightly different bottom half, but you can see what the missing top part should look like. Also, you can see what the actual combo should look like here https://airandspace.si.edu/collection-objects/sextant-aircraft-periscopic-d-1-kollsman-instrument-corporation . The fact that the top half is missing doesn’t really matter if you’re only going to screw the mount onto plywood for ground use, but it does rather take away the authenticity.  If you’re intending to use it through a shed roof or a caravan, then it’s not really suitable, because the rain will leak in.  Despite their rarity, it’s worth waiting for a better mount than this.

This is a bubble model, so you’d need to ask questions about whether the bubble’s still there and adjustable.  The chances are the seller will then claim to have no specialist knowledge.  Mainly though, the price asked is extortionate.  You can get nicer sextants and mountings than that one for a lot less if you’re prepared to wait.  Even if I was really anxious to buy it, I wouldn’t pay more that $100 for the sextant and $50 for the half mounting.  DaveP

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