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    Re: Height by sextant angle
    From: Francis Upchurch
    Date: 2014 Dec 14, 08:56 -0800

    Sorry folks, this has got me all excited!

    Simple solutions are great. Check out the famous "Dambuster" RAF raid with the Barnes Wallis bouncing bomb on the Ruhr dambs, circa

    1943? I think? Had to fly the huge Lancaster bombers at exactly 60 feet to get the bomb to bounce correctly. Way beyond the Altimeters of the day. Solution. KISS.  spot lights, fore and aft, angled to produce a single spot reflection at exactly 60 ft. This is the reverse of the airship angle alt method that started this discussion.

    We did similar, diving ship wrecks in the  1980s before accurate cheap GPS. We used simple transit marks of prominent shore features, rocks, church spires etc. Usually accurate to within a few feet without any equipment, instruments  or anything. Fishermen have used that for millenia.

    Nothing new under the sun.

    Francis

     

       
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