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
    Silicon Sea Cruise: Leg 38
    From: Dan Hogan
    Date: 1998 Mar 31, 1:39 AM

    NOTE to SS'rs:
    It has been pointed out that I have taken too many short cuts in my
    effort to ease my work on Silicon Sea. So back to basics. The
    current data provided on a Pilot Chart is the average velocity in
    miles per day. I will state them in either as "Pilot Chart 260d 8m"
    or for a specific problem as "Set ddd, Drift .xx Kts/Hr."
    Chart(s): Plotting Sheet
    Sight Reduction and
    Dead-Reckoning problem     Leg 38  033198   Test your knowledge!
    ----------------------     ------  ------   --------------------
    On 14/07/1996 @ 12:21:28ZT our Lat was 14d 41.1'S, EP Lon was
    101d 07.1'E. TC was 125.4, Speed 10 Kts, Var 4dW, Dev 4dW. Sky still
    overcast. It was obvious that we had missed Cocos/Keeling Island(12d
    02.0'S 97d 00.0'E).
    1)  What is the TC for Cape Leeuwin(34d 15.0'S  115 06.0'E) from the
        Estimated Position(14d 41.1'S 101d 07.1'E)? we estimate current
        Set 260d Drift .33 Kts/Hr
    We continue on the TC to Cape Leeuwin. At 18:21:28ZT(Zone Time) we
    take a sight of a bright body between a break in the clouds.
     Hs			 Compass Bearing
     58d 49.3'	 100.9d
    2)  Excluding Current, what is the DR position to use for the Sight
    --  ----------------------------------------------------------------
    3)  a) What Celestial Body is this?
        b) What its Zn?
    --  -------------------------------
    4)  Using the 12:21:28ZT Estimated Position and TC, the 18:21:28ZT
    	Body LOP, what is the 18:21:28ZT DR?
    -- ----------------------------------------------------------------
    According to our Pilot Chart of The Indian Ocean for July, the
    average *daily* current in our area is, 260d 8m.
    5)  Based on the Pilot Chart data, what is our current estimated
        Speed Made Good(SMG) on our TC to Cape Leeuwin?
    --  -------------------------------------------------------------
    6)  What is the Compass Course to Steer?
    7)  At this SMG how many days(nearest tenth) is it until we reach
        Cape Leeuwin?
    --  ------------------------------------------------------------
    Lat & Lo = XXd XX.X', Date=DD/MM/YY, HE 8 Feet, Index correction
    -.2', Time hh:mm:ss in UTC/GMT. Silicon Sea is a medium displacement
    sailing vessel, 40 Feet LOA. 38 Feet LWL; Cutter rigged. Looks a lot
    like a Mason. Can tack to 45d. Dist to Horizon: Nmi = SQRT HE@mtrs x
    2.07; Nmi = SQRT HE@ft x 1.17. Water Tank = 60 gal(Imp.). Fuel Tanks
    = 90 gal (Imp.). Fuel consumption .450 gal/Hr at 8.3 Kts.
    PLEASE respond with your results and thinking on these exercises to
    the NAVIGATION list at large. If you have questions or problems, A
    lot of folks on the list are knowledgeable and willing to help. Any
    questions or doubtful areas will be responded to promptly. Let us
    hear from you soon!
    Good Navigating!
       -=The Navigation List Working Group=-
            Peter Smith  - psmith@wellspring.us.dg.com
            Ron Legere   - ronald.legere@yale.edu
            Tony Severdia- anthonys@pacbell.net
            Wes Murfin   - wmurfin@onslowonline.net (Cartographer)
            John Simmonds- mobi@netconnect.com.au
            Jim Manzari  - manzari@bluewin.ch
            Dan Hogan    - dhhogan@lightside.com
    Dan Hogan WA6PBY
    "Gacha" Catalina 27
    (1) dhhogan@lightside.com
    (2) dhhogan@concentric.net
    =-=  TO UNSUBSCRIBE, send this message to majordomo@ronin.com:     =-=
    =-=      unsubscribe navigation                                         =-=

    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