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: Calculate new coordinates given bearing and distance?
    From: David Pike
    Date: 2015 Nov 24, 16:12 -0800

    Sam you wrote:  To find the new Latitude use the Hc formula but for declination use the arcosine of the distance travelled divided by the radius of the earth in nm.  LHA is course bearing.  Ap Lat. is the Latitude of origin.  To find the Longitude use the typical formula to obtain Zn with the Latitude, obtained above, as the Hc.  Once you get the answer, subtract or add it to Longitude of origin.  Mathematically there has to be some way to determine whether to subtract or add the result from the Longitude of origin. This probably needs some refinement....but for the moment it worked.

    I think I see what you’re doing.  You’re effectively substituting the start and finish points as two corners of a skewd PZX triangle and the distance between them as the side joining them – noble stuff, but pretty complicated and a bit beyond my powers of comprehension at 00.08.  I think I’ll stick with my method with a Douglas protractor, albeit ‘flat Earth’.  W.r.t. how to deal with the sense of chlong, why not just visualise it (or write a condition)?  If course is in the sector 360 through 090 to 180, the destination longitude will be east of the start point, and if it’s in the sector 180 through 270 to 360 it’s west of the start point.  DaveP

    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