Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
    Re: Ogura IJN
    From: Stan K
    Date: 2017 Aug 9, 20:14 -0400
    Greg, 

    You said,
    The arc sin of  (sin declination divided by sin latitude) = PV.  
    Isn't that formula for the altitude of a body on the prime vertical, and doesn't it only apply if latitude and declination have the same name and dec<lat?

    Stan


    -----Original Message-----
    From: Greg Rudzinski <NoReply_Rudzinski@fer3.com>
    To: slk1000 <slk1000---.com>
    Sent: Wed, Aug 9, 2017 3:45 pm
    Subject: [NavList] Re: Ogura IJN

    David,
    You might want to give a slide rule a try for solving azimuth. I like slide rules that have the S scale just above the C scale on the slide (see Post Versalog 1460). First solve for prime vertical if the quadrant of the meridian angle is in doubt. The arc sin of  (sin declination divided by sin latitude) = PV.  To solve for Z = arc sin (cos dec sin t / cos Hc) . Use Zn rules to get azimuth. I prefer the slide rule to the Rust diagram seen in Weem's Line of Position Book. The Ix graph is the best compact azimuth method and fits on one side of a standard sheet of paper. All useful formulae and rules can be jotted down on the blank back side for inclusion into a short table, sextant box, or wallet. 
    Greg Rudzinski

    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