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: Time Zone Designations
    From: Henry Halboth
    Date: 2017 Jan 4, 01:52 -0500

    It was always my undrstaning that Zone Time was kept aboard ship in order to maintain a sense of normalcy about life in general, and as related to sleeing, mealtimes, etc., in relation to passage of the Sun; further in the Navy the ship’s position was officially logged at 0800. 1200, and 2000, while in the MM it was officially logged only at 1200 hours and certain statistical data relating to the day’s run calculated for record purposes I quite frankly cannot imagin the turmoil and confusion that would be created by keeping UT consistently on a long voyage. You could wind up eating breakfast and lunch in the dark and dinner in bright daylight, or for that matter all three in the dark, As for sight taking - I see no problem, you read the chronometer time in UT and calculate accordingly and simply note your LOP and/or position in Zone time. I never had or heard of a problem in relation to this until brought up on NavList/   

    On Wed, Jan 4, 2017 at 12:08 AM, Greg Rudzinski <NoReply_Rudzinski@fer3.com> wrote:


    Can't speak for the US Navy but in the US Merchant Marine prior to Y2K watches were 4 on 8 off. When clocks got advanced 1 hour to the next time zone going East (23 hour day) then evening and early morning watches stood 20 minutes less (3 hr. 40 min.). Going West watches stood 20 extra minutes after clocks were retarded one hour (25 hour day). On ocean going tugs watches were generally 6 on and 6 off. Some ships had clock systems that changed all the clocks onboard at the same time from the bridge.  Fast ships in the days of cheap fuel were capable of crossing two time zones in day (SeaLand  SL7 Container Ships). 

    Greg Rudzinski

    View and reply to this message

    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