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: A fluke of 0.0 intercept with Altair.
    From: George Huxtable
    Date: 2010 Sep 22, 08:42 +0100

    Antoine wrote-
    
    ...if we use tenths of arc minutes instead of arc seconds - which has 
    nowadays become most usual navigational practice -, we could as well use 
    the Civilian Aviation Format (this the one I am using to enter coordinates 
    in our Honeywell Flight Management Computers) through entering such 
    coordinantes as : N3013.2W08152.3
    Such format is quite compact. It also eliminates the use of ' (arc minute 
    symbol) which I sometimes cannot get to show up correctly in the NavList 
    Forum posts. It can also be easily extended if more significant figures are 
    required : N30�13'13" W081�52'16" will then show up as N3013.217W08152.267
    
    If using this specific aviation code, the height quoted by Paul would then 
    have been 4026.2 (or 40�26'2 in its classical transcription) while using 
    the 40.262 figure would imply decimal degrees (which was you initial and 
    early guess).
    
    This is just a suggestion and an idea in the air ... What do you think, my 
    Fellow Maritime Navigators about such an aviation format ?
    
    ===================
    
    Response from George-
    
    HORRIBLE! A recipe for misunderstanding and disaster! May be OK for 
    entering data into a very specific instrument, but not in general 
    discussion in a forum such as ours, in which all sorts of quantities may 
    appear. Decimal numbers should mean decimal numbers, without a hidden 
    sexagesimal intrusion into them, which would take us back into the confused 
    number-world of the ancient Greeks and the Babylonians.
    
    Presumably, Antoine's format requires 4 digits before the decimal point, 
    for latitudes (up to 90º), and 5 digits for longitudes (up to 180º). What 
    about sextant angles, then? Would altitudes (never more than 90º) be 
    allocated 4 digits? In which case, lunar distances (up to 120º) would 
    require 5.
    
    If a contributor can't find acceptable symbols for degrees and minutes, he 
    can always use the appropriate letters, d, m, s. Where's the problem?
    
    George.
    
    contact George Huxtable, at  george{at}hux.me.uk
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. 
    
    
    
    
    

       
    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