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: Sextant auction. Windham, NH, May 20
    From: David Pike
    Date: 2018 May 7, 09:05 -0700

    I was interested in the photographs of the Hughes Aircraft Sextant Lot 689 often described as a Flying Boat Sextant, although it would have been useful in any maritime aircraft flying in clear conditions with an accurate knowledge of sea level pressure.  Its number 28,125 and certificate 16th Dec 1941 is not much younger than my own Mate’s Three Circle Sextant 25,410 whose certificate is dated 16th Jan 1941, and it is signed by the same D A Perkins.  The interesting thing is that both arcs are claimed to require no correction although the units are different.  My Mate’s six inch radius sextant reads to ten seconds of arc and Mr Perkins claims the arc requires zero seconds corrections.  For the aircraft sextant, which is only three and a half inch radius and has no Verniers, Mr Perkins claims that it reads to one minute of arc and requires zero minutes corrections.  Therefore, it’s interesting to speculate what Mr Perkins is actually claiming on the certificate.  I presume it means “For the purpose we expect you to use this sextant and the accuracy you can expect due to the conditions your working under, you don’t need to worry about the cutting and marking accuracy of the arc.”  Comments please.  Dave P   

       
    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