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
    Re: Determining Elevation with a Sextant
    From: Dave Weilacher
    Date: 2002 Feb 28, 10:59 -0500

    This answer seems elegant in its simpicity.
    Original Message:
    From: Dov Kruger dkruger@RIGHTTRAK.COM
    Date: Thu, 28 Feb 2002 10:28:59 -0500
    Subject: Re: [NAV-L] Determining Elevation with a Sextant
    Dan Allen wrote:
    >Does anyone have any clever ideas about determining one's elevation above sea 
    level using a sextant?  What if one knows one's
    >latitude and longitude exactly -- would that help?
    Assuming you have a good horizon, meaning you are on a mountain by the
    sea, simply:
    1. Determine a line of position using the usual sight reduction using a
    zero dip, or for slightly increased accuracy an assumed dip.
    2. Assuming everything else is exact, the amount by which your estimate
    is off your actual position represents the error in dip.
    3. dip = 0.9692 * sqrt(h) (h in feet), therefore h = (dip/.9692)^2
    If you assume zero dip, there will be a slight error due to the
    difference in refraction but it will be negligable, I wouldn't bother.
    You only need one line of position because you already know your
    position, but two will help verify your answer.  You could average the
    two results.
    mail2web - Check your email from the web at
    http://mail2web.com/ .

    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