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    FW: Silicon Sea: Leg 79
    From: Russell Sher
    Date: 2001 Sep 19, 12:26 AM

    Here are some answer attempts - any verifications?? My intercepts for Q3
    seemed a bit long for some of the sights.
    Chart(s): Plotting Sheets
    Sight Reduction and
    Dead-Reckoning problem     Leg 79  091701   Test your knowledge!
    ----------------------     ------  ------   --------------------
    Our last FIX position was (03d 00.00'N  082d 00.0'W) @ 10:51:11UT @
    26/06/2001. We are sailing toward MOP1(03d 00.0'N  110d 00.0'W) where
    we will turn and head for Hawaii.
    At a Log distance traveled of 710.5 Nmi from the FIX position. TC 270.0d,
    Speed 10.0 Kts, we determine that we have entered the Equatorial Counter
    1)  What is the DR position on entering the Equatorial Counter Current?
    departure = 710.5 nm, since D lat. = 0.
    Diff. Long in minutes = 710.5 *cos (3)), so D Long = 11 deg 49.5', so DR
    = 093 deg 49'W
    DR latitude  unchanged: so...
    DR = 03 deg 00'N, 093 deg 49.5'W.
    --  -------------------------------------------------------------------
    On the morning of 30/06/2001 we manage the following sights:
            Body            UT/GMT          Hs
            Fomalhaut       11:53:00        54d 01.8'
            Deneb           11:55:10        30d 03.8'
            Altair          11:57:20        27d 35.1'
            Saturn          11:59:05        23d 17.4'
            Venus           12:04:11        38d 50.8'
    2)  What is the DR position at the time of the Fomalhaut sight?
    --  -----------------------------------------------------------
    distance travelled =  10 knots * 97.3 hours = 973.08 nmiles = departure (due
    Diff. long in minutes = 973.08 * cos (3)=971.74' from DR 26/06/2001
    D Long = 15 deg 50.3', so DR long = 082 deg 00'W + 16 deg 11.7' = 098 deg
    11.7' W
    DR latitude  unchanged:
    DR = 03 deg 00'N, 098 deg 09'W.
    3)  What is the position FIX?
    --  -------------------------
    using Navigator Light:
    Lat:  03�32.2'N
    Lon: 097�30.5'W
    Intercepts/Az For each LOP as follows:
            Fomalhaut: 37.6' Away/Zn = 202 deg
            Deneb    : 4.6 To / Zn =  322 deg
            Altair   : 29.2' Away / Zn = 278 deg
            Saturn   : 50.2' To / Zn = 069 deg
            Venus    : 51.4' To / Zn = 072 deg
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