Chart(s): redsea6.gif, Plotting Sheets

Sight Reduction and 
Dead-Reckoning problem     Leg 30  070197   Test your knowledge!
----------------------     ------  ------   --------------------

The weather has been solid overcast since our last FIX 25/06/1996 @
19:10:23GMT(11d 38.1'N  44d 58.8'E), Temp is 85dF. We are headed for a point N
of Cape Guardifuai(12d 10.0'N  50d 45.0'E).

We have sailed for 20:44:37Hrs at a TC 85.4, Speed of 7.3Kts. Var00.0d Dev2dW.
Current Drift 10 @ Set 32d.

1)  What is the compass course steered?
    What is our EP(Estmated Position)?
--  ----------------------------------

We see some openings in the clouds and take the following Sights.

     GMT            Body           Hs             Zn
     15:56:00       Regulus        44d 19.1'      272.6d        
     15:59:12       Vega           17d 25.5'      053.4d          
     16:04:21       Alkaid         55d 04.5'      006.5d              


2)  What is our FIX?
--  ----------------

We plot a course to our waypoint N of Cape Guardifuai(12d 10.0'N 50d 45.0'E).
Var 00.0d, Dev 2dW, Current set 265d drift 8Kts, Speed 7.3Kts. The
sky is a solid overcast.

3)  What is the TC and Distance to this waypoint?
    What is our estimated time in hours to the waypoint?
--  ----------------------------------------------------

4)  What is the SMG?
--  ----------------

The June Indian Ocean Pilot Chart shows a favorable current along
the coast of Yemen. A distance of about 90 miles north of our
course. We power at a speed of 8.3Kts, on a TC of 25d.

5)  What is the expected DR position at the end of this time?
--  ---------------------------------------------------------

6)  From our last FIX what is the ETA and Date at our DR point?
--  -----------------------------------------------------------

At the time of our ETA we find we are nearing considerable shipping
traffic both East and West bound. So we set a course paralleling the
shipping lanes but south of them to avoid as much traffic as possiable.
We select a point at (16d 00.0N 54d 30.0'E) as a turning point to
head into the Indian Ocean. Var0.0, Dev 2dW, speed 9Kts.
Current drift 10, set 68d.

7)  What is the Dist and TC to this point?
--  --------------------------------------

8)  What is the course to steer?
--  ----------------------------

9) What is the elapsed time in hours to our new waypoint?
-- ------------------------------------------------------

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
        
