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: Are higher altitude sights inherently less accurate?
    From: Alexandre Eremenko
    Date: 2012 May 2, 11:54 -0400

    Randal,
    Yes, there are more factors that can contribute to your errors
    with higher altitudes. One of them is the sextant arc imperfection.
    I've seen many sextant certificates on e-bay.
    In almost all cases when a certificate is available the arc errors
    increase towards the end of the arc.
    What sextant do you use?
    
    There is also a pure mathematical reason: it is harder to keep the
    sextant vertical by swinging the arc (I mean natural horizon).
    With artificial horizon it is even harder to align
    exactly, and to ensure that the
    sextant plane is vertical.
    
    
    
    Alex
    
    On Wed, 2 May 2012, Randall Morrow wrote:
    
    >
    > I have been loking at averages of my sights and higher altitudes seem to 
    have larger intercepts. Using an AH and reading Hs of over 100 degrees, Ha 
    over 50.  It seems to take longer to find high altitude bodies in the mirror 
    but is there something in the process which introduces more risk of error?
    > ----------------------------------------------------------------
    > NavList message boards and member settings: www.fer3.com/NavList
    > Members may optionally receive posts by email.
    > To cancel email delivery, send a message to NoMail[at]fer3.com
    > ----------------------------------------------------------------
    >
    >
    >
    >
    > View and reply to this message: http://fer3.com/arc/m2.aspx?i=119343
    >
    >
    >
    
    
    
    

       
    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