Route Planning Problem     Leg 28  052297   Test your knowledge!
----------------------     ------  ------   --------------------

During the days of hectic preparations of maintenance and stores
provisioning for the long sea voyage. The Skipper develops the navigation
plan for the anticipated voyage and prepares for possiable problems. There
are 6 crewmembers. An alloted water consumption estimate, including cooking
and washing, is 1.5 gal(imp.) per/man/day.

It is late in the season and we want to make as fast a crossing of the
Indian Ocean as possiable. So our next planned landfall, after departing
Djoubiti, is Cape Leeuwin, Australia. Our next planned port of call is
Sydney Harbor.  We lay a course across the Indian Ocean and plot a set of
waypoints:
                                        Lat       Lon
     Djibouti                      11d 36.5'N  43d 07.5'E
     Point N Cape Guardifuai       12d 10.0'N  50d 45.0'E
     Point W Cape Guardafui        11d 55.0'N  51d 27.0'E
     Cape Leeuwin                  34d 15.0'S  115d 06.0'E
     Turn to Bass Strait           38d 54.0'S  120d 00.0'E
     Bass Strait                   39d 18.0'S  144d 00.0'E
     Turn to Sydney                38d 00.0'S  150d 20.0'E
     Sydney Harbor                 33d 50.0'S  151d 20.0'E 

1)  Using your favorite Sailings method, what is the total
    distance from Djibouti to Sydney Harbor?
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2)  Being conservative we estimate a 7 Knts crossing speed, what
    is the time in days, to the nearest tenth, for the passage
    from Djibouti to Sydney Harbor?
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3)  What is the anticipated total water consumption for the trip?
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Since water weighs about 10 lbs to the gallon we are limited to how
much we can carry. We add an additional 60 gals in containers.

4)  In what way can we make up for the insufficient water? 3 methods.
--  -----------------------------------------------------------------

5)  Based on the fuel consumption (see Note below) how far can we
    motor at the maximum motor speed?
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We examine the Pilot Chart of The Indian Ocean for the month of July.
Taking the winds and currents into consideration, We see that they
dictate a course that stays north of 00.0d Lat. until 80d E longitude,
then we can turn and make for Cape Leeuwin with more favorable winds.

6)  What is the TC and Dist from Point W of Cape Guardafui
    (11d 55.0'N  51d 27.0'E) to (00d 00.0'  80d 00.0'E)?
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7)  What is the TC and Dist from the (00d 00.0'  80d 00.0'E)
    to Cape Leeuwin(34d 15.0'S  115d 06.0'E)?
--  --------------------------------------------------------

8)  Based in this revised plan what is the new total Dist enroute?
    How many days passage at our 7 Kts planning speed?
--  --------------------------------------------------------------

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.). 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 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

