Welcome to the NavList Message Boards.


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

Compose Your Message

Add Images & Files
    Lindbergh-Weems Second-Setting Watch -- Notes on Design and Use
    From: Ed Popko
    Date: 2018 Nov 26, 02:59 -0800

    I received enough questions about the Lindbergh-Weems Second-Setting navigation watch that I decided to consolidate my notes and PostScript simulator output into a short paper. Attached is an overview of the watch's various dial features and examples of how to use the hour/minute/second hands to calculate the sun’s Greenwich Hour Angle from Greenwich Mean Time.

    This 1930's watch from the Golden Era of Aviation is the first true pilot’s watch specifically designed for celestial navigation. All modern pilot watches owe something to this one. Longines company still manufacturers it; a modernized version is part of their Heritage line of watches.

    I would like to recognize Brad Morris for his encouragement and comments while preparing this paper. His input greatly improved the paper’s clarity and accuracy. Stan Klein did a great job of proofing and cross checking the final test. Thanks to both of them.
    NavList posts by Gary LaPook and Paul Dolkas started the Lindbergh-Weems watch discussion (see the Bibliography for specific references). Their threads inspired me to look closer and write a PostScript simulator to study how the watch works. I want to thank them for the head start they gave me.

    Ed Popko

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    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 Settings

    Posting Code:

    Custom Index

    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