Sight Reduction and
Dead-Reckoning problem     Leg 34  091197   Test your knowledge!
----------------------     ------  ------   --------------------

It is 01/07/1996 @ 15:20:53ZT. We are at our EP(04d 30.0'N  73d 00.0'E)
for our approach to Mali'. Looking at the chart we see that the fringing
reef on the West side of Mali' Atoll is about 20.5 miles ahead. The Maldive
Islands are a series of low laying atoll islands with fringing reefs. The
currents are strong and unpredictable. The harbor and the Port of Entry are
on the South East side of the atoll, on the opposite side of the fringing
reef at our arrival point.

1)  Within 5 minutes. What is the the approximate Zone Time(ZT) of
    SunSet(SS) at Mali'?
--  --------------------------------------------------------------

We set the following courses from the EP to make for the atoll entrance
and to clear any reef danger. We head NE through the Kardiva Channel.
Constant vigilence will be required until we are anchored inside the Mali'
Atoll lagoon. Var 4dE, Dev 3dW. Speed 9 Kts. Wind Force 4 @ 270d.

         Leg    TC        Dist          Current

          1    047.4d     42.9 mi       Drift  8 @ 127d.
          2    145.7d     36.8 mi       Drift 10 @ 183d
          3    233.0d     18.8 mi       Drift  5 @ 045d

2)  What is the Compass Course/Course to Steer for each of the three legs?
--  ----------------------------------------------------------------------

3)  What is our ETA in Zone Time(ZT) at the Mali' Atoll entrance?
--  -------------------------------------------------------------

We log the turn to the TC of 47.4d at 15:20:53ZT. About 27 miles ahead, on
Leg 1, lies a protruding reef at(04d 45.0'N  73d 22.0'E).

4)  What is the Compass Course(CC) Danger bearing to the reef?
--  ----------------------------------------------------------

5)  At what ZT can we expect to be abeam of the danger reef?
--  --------------------------------------------------------

On our approach to the Maldive Islands the cloud cover begins to clear.
Near sunset we had only about 30% broken cloud cover.

6)  Can we use the moonlight as an aid in piloting around the Atoll?
    What is the age of the Moon?
--  ----------------------------------------------------------------

On our Leg 1 course we post a lookout. We watch for breakers in the water
ahead. The lookout sits on the speaders eyes at 33 feet.

7)  At what distance in nautical miles should breakers be spotted
    by the lookout?
--  -------------------------------------------------------------

On our arrival at the entrance we contact Mali' Harbor Patrol via VHF
Channel 16. The escort us in to anchorage in the lagoon in 30 feet of
water. It is protected
and no detecable swell. We are told to remain on board until Customs clears
us in the morning. We drop anchor at 02:10:00ZT.

8)  What is the date?
--  -----------------

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


