Chart(s): redsea6.gif

Pilotage and 
Dead-Reckoning problem     Leg 27  050297   Test your knowledge!
----------------------     ------  ------   --------------------

|On 15/06/1996 at 18:37:30 we plotted a course to Djibouti(11d 36.5'N
43d 07.5'E) from Bar el-Mandeb Island(12d 38.1'N  43d 27.5'E). On
checking our chart we find that a large Ethiopian headland lies on
our route. We need to re-plot our course. We want to stay offshore
so we pick a point at (12d 00.0'N  43d 33.9'E). And make the voyage
in 2 legs. Var0.0d, Dev4dE. Speed 9Kts.


1)  What is the TC and Dist from Bar el-Mandeb to this point?
--  ---------------------------------------------------------

2)  What is the TC and Dist from the selected point to Djibouti?
--  ------------------------------------------------------------

The wind is 270 at Force 4, current is 4Knt@set35d.

3)  What is the Compass Course for the first leg?
    What is the Compass Course for the second leg?
--  ----------------------------------------------

4)  What is the total distance to Djibouti from Bar el-Mandeb?
--  ----------------------------------------------------------

5)  Using the Speed Made Good(SMG) for each leg what is the Estimated
     Arrival Time(ETA) time and Date at Djoubiti?
--  -----------------------------------------------------------------

As we approach Djibouti we have trouble locating the harbor due to
poor visibility. The chart shows the Moucha Islands(11d 43.8'N
42d 14.2'E) North of a jetty(11d 38.4'N 43d 06.8'E) at the entrance
to Djibouti Harbor. 

6)  What is the differeance between the two TC's?
    Is it practical to sail mid-way between the two TC's?
--  -----------------------------------------------------

7)  What form of navigation is practiced as a result of your answer
    to the second part of Q6 on the second leg into Djibouti?
--  ---------------------------------------------------------------

8)  We are entering a foriegn country for the first time, as a
    coutresy what flags should we be flying?
--  ----------------------------------------------------------

Note:
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.).

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 Navgation List Working Group=-

        Peter Smith  - psmith@wellspring.us.dg.com
        Ron Legere   - ronald.legere@yale.edu
        Tony Severdia- anthonys@ix.netcom.com
        Wes Muffin   - wmurfin@onslowonline.net (Cartographer)
        John Simmonds- mobi@netconnect.com.au
        Dan Hogan    - dhhogan@lightside.com
        
