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Subject: Re: Answers to Leg 84
From: Dan Hogan (dhhogan1@XXX.XXX)
Date: Sun Oct 06 2002 - 12:44:56 EDT
On 4 Oct 2002, at 18:29, Arthur Pearson wrote:
> 1) ZT = 16:27 on 20/7/02
Uhh..recheck this. ALL you need is time of Sunrise at Hilo + the elapsed time
to the departure FIX.
> 2) Using Mercator calculations in CelestNav, total distance of all legs
> is 303.
Off a little. I have found CelestNav to be "tricky" because of what it wants
in info. The problem is just a DR traverse from point-to-point.
> 3) 303/9.3 = 32.6 hrs = 32 hrs and 36 min.
Close
> 4) Sight directly overhead is very difficult, hard to know where to
> bring it down. That said, declination on this day = 20d 31' which is
> therefore our approximate latitude, which corrects or DR latitude by 7
> miles)
Right
> 5) Solving the sights in Celestnav and plotting them yields 26d 00'N and
> 157d 00' W. CelestNav fix calculation yields the same position exactly.
OK
> 6) Mercator calculations in CelestNav give TC = 102, D = 4.8nm. Current
> has negligible effect on course to steer, corrections of Var. and Dev.
> give CC = 90.5 (anyone who can steer within 0.5 degrees, please email me
> with instructions)
OK
> 7. Speed adjusted for current = 9.1. Divided into distance yields T = 32
> minutes. Look over the bow and you won't need the compass.
OK
[Sniped original message]
Dan Hogan
dhhogan1@XXX.XXX
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