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    SS Leg 82 Question 8a
    From: Peter Fogg
    Date: 2001 Dec 03, 11:18 PM

    'My apologies to all. I forgot to delete the answers from the posted
    of Leg 82.   Dan Hogan'
    Excepting the answer for Q 8a
    '8a) As an aside try calculating from the RFIX to Sydney (33d 50.0'S
    151d 20.0'E)
    So here is my answer:
    RhumbLine Course= 225.9d   Dist= 4507.5 nm
    GC(Init)      Course= 225.8d   Dist= 4505.1 nm
    Was mildly surprised that there was not more of a difference between
    Rhumbline and GC courses. As a check worked it out for the opposite
    trip. The distances were the same but the GC(Init) Course= 54.8d, the
    opposite of which is 234.8d, which appeals more, if only because it is
    more different.
    Mercator and Mid-Latitude remain mysteries, for the moment at least.
    Incidentally, know S33 50' E151 20' well, its about 2 miles to the east
    of South Head, the entrance to Sydney Harbour. Go out there to practise
    taking sights, its a convenient DR, although too close to the coastal
    cliffs for sights to the west. You can't just sit there, even if the
    prevailing fine weather NE winds are absent (they often calm down as it
    gets dark) because of the south setting Eastern Australian Current.
    Unlike the Gulf Stream, all anybody here seems to know or care is that
    it flows at from 2 to 4 knots. I suspect that it is just as complex an
    ocean river as the Gulf Stream. Know that its strength can vary greatly,
    and that protruding headlands can send a weaker counter current flowing
    to the north, close to the coast. It seems to be strongest along the 100
    fathom line, 8-10 miles offshore, the edge of the continental shelf.
    Many thanks to Dan Hogan and team for the SS series. Enjoy them greatly,
    even when I can't achieve the same answers !
    Peter Fogg

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