Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    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

     

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site