Two On A Big Ocean The Story of the First Circumnavigation
of the Pacific Basin
in a Small Sailing Ship


      

Other Books by
Hal Roth
| Home | Mailing Lists | Bookstore | Weather | Tide Predictions | Bowditch |

Silicon Sea: Leg 74


Subject: Silicon Sea: Leg 74
From: Dan Hogan (dhhogan@XXX.XXX)
Date: Thu Jun 14 2001 - 09:04:57 EDT


Chart(s): Plotting Sheet

Sight Reduction and
Dead-Reckoning problem Leg 74 061401 Test your knowledge!
---------------------- ------ ------ --------------------

Our last Running FIX(13d 37.8'N 68d 10.5'W) 16:30:29UT @XXX.XXX
We were headed for Aruba Gap(13d 50.0'N 70d 00.0'W).

On 02/06/2001 @XXX.XXX7 Nmi from our RFIX we made a course
change at the Aruba Gap (13d 50.0'N 70d 00.0'W) waypoint. Our destination is
Cristobal, Panama(09d 23.0'N 79d 55.0'W). We are anticipating a transit of the
Panama Canal.

Var 8.0dW, Dev 1.0dE . Current Set 275.0d Drift 1.5 Kts. Speed 10.4Kts.

1) What is the the TC and Distance from Aruba Gap(13d 50.0'N 70d 00.0'W)
   to Cristobal, Panama(09d 23.0'N 79d 55.0'W)?
-- ---------------------------------------------------------------------

2) What is the Compass Course(CC)/Course-to-Steer?
-- -----------------------------------------------

Since our turn at Aruba Gap(13d 50.0'N 70d 00.0'W)We have been sailing in a
steady wind and clear skys.

At 05:16:28ZT @XXX.XXX
Speed 10.4 Kts, TC 245.5d.

3) What is the 05:16:28ZT DR position?
-- -----------------------------------

We take the following sights:

    Body UT/GMT Hs

    Fomalhaut 10:17:22 47d 14.7'
    Deneb 10:17:56 51d 52.0'
    Altair 10:18:00 59d 18.2'
    Vega 10:18:46 37d 34.3'
    Venus 10:19:33 33d 20.0'

4) What is the position FIX?
-- -------------------------

Speed 10.0 Kts. Var 5dW, Dev 1.5dE. Current Set 100.0d Drift 0.7 Kts.

5) What is the TC and Distance to Cristobal(09d 23.0'N 79d 55.0'W)
    from the FIX position?
-- ----------------------------------------------------------------

6) What is the ZT and Date of our ETA at the Cristobal waypoint
    (09d 23.0'N 079d 55.0'W)?
-- ------------------------------------------------------------

NOTE:
Lat & Lo = XXd XX.X', Date=DD/MM/YY, HE 9 Feet, Index correction
-2.5', Time hh:mm:ss in UT,unless otherwise stated. Silicon
Sea II is a 34,000 lb(15.40t) displacement sailing vessel, 48' 3"
(14.70m) LOA. 39' (12.00m) LWL; Cutter rigged. Can tack to 45d.
Water Tanks = 220 gal(1000 ltrs). Fuel Tanks = 155 gal(700 ltrs).
Fuel consumption .675 gal/Hr at 8.5 Kts. DR(Ded-Reckoning)=position
by sailings, EP(Estimated Position)=DR+current affect. Dist to
Horizon: Nmi = SQRT HE@XXX.XXX

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 - Smith_Peter@XXX.XXX
        John Simmonds - johnsimmo@XXX.XXX
        David Weilacher - daveweilacher@XXX.XXX
        Tony Cappiello - cappiello@XXX.XXX
        Frank Norris - NORRIS_FRANKLIN_H@XXX.XXX
        Sam Chan - schan@XXX.XXX
        Dan Hogan - dhhogan@XXX.XXX

Dan Hogan WA6PBY
C27 "Gacha"
dhhogan@XXX.XXX
Nav-L Page: http://www.wa6pby.com





| Home | Mailing Lists | Bookstore | Weather | Tide Predictions | Bowditch | Trawlerworld |