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Roger Helio Roger Helio is offline
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First recorded activity by BoatBanter: Apr 2008
Posts: 7
Default celestrial navigation anyone?


"Edgar" wrote in message
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"Roger Helio" wrote in message
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"Wayne.B" wrote in message
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It might be possible but I doubt it. There used to be a sextant
designed for aircraft navigation in WW II that used an artificial
horizon of sorts but those guys were happy to know where they were
within 20 miles or so.

That was not a sextant. It was called an octant.

Here's one:

http://www.icarusbooks.com/images/1458.jpg

That is not an octant. It looks like a bubble sextant as used on
aircraft..
An octant is exactly the same as a sextant except that is is constructed
to
read to 45 degrees against a sextant's 60.
A sextant can therefore measure a wider angle than an octant.
. I have an octant that my grandfather used. It is made of
ebony and has ivory engraved scale read with a vernier, but in all
essential
respects is identical to a sextant.



It came from this page:

http://www.icarusbooks.com/nonpaper.htm

Click on the link CS1458 "Aircraft octant".

Here's one on sale at eBay:

http://cgi.ebay.com/WWII-NAVY-OCTANT...QQcmdZViewItem

Here's a US Navy manual on them:

http://cgi.ebay.com/SEXTANT-OCTANT-M...2em118Q2el1247

Here's another manual:

http://cgi.ebay.com/Link-Bubble-Sext...2em118Q2el1247

Amelia Earhardt used an octant.

Eddie Rickenbacker used one on his B-17. Octants were standard issue on
B-17s.

All US military aviation navigators used octants.


What type of navigation uses a radiant? A radiant is an "octant" that covers
360 degrees. That will certainly stump all of you since no one even knew of
the existence of an octant. (Hint: octants are top secret, only I know about
them!). The term "sextant" was used for these devices so as not to confuse
those of minimal mental capacity, apparently for good reason.