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Subject: Re: Silicon Sea: Leg 85
From: Dan Hogan (dhhogan1@XXX.XXX)
Date: Thu Nov 14 2002 - 09:10:39 EST
On 12 Nov 2002, at 14:30, Paul Hirose wrote:
> 1. Total distance from Hanalei Bay to L.A. Light = 3990 miles
Too high. waht method are you using for calculations? Try using Mid-Latitude
leg-by-leg.
> 2. Based on a Speed of 10 Kts it will take 16.6 days to L.A. Light.
See Q1.
> 3. At 7.5 gallon/day total water consumption, total to the L.A. light
> will be 125 gallons. The vessel has a 220 gallon capacity, so there
> appears to be enough.
OK
> 4. TC from Hanalei Bay to MOP1 is 013.
OK
> 5. Departure was at local apparent noon.
Right
> 6. TC to MOP1 = 014.
OK
> 7. Steer 1 degree left for current and subtract 11.5 deg compass
> error. Compass course = 002 to MOP1.
OK
>
> Mostly I used plotting sheets and did the computations graphically.
> For the current correction I'd normally use an E-6B slide rule, but
> this time I drew a current triangle on the plotting sheet for the
> sake of variety.
If you like plotting sheets and non-calculator try Mid-Latitude for the leg
calculations.
> Looking at the answers, my distance was about 25% off. Even on
> plotting sheets I think I should have done better. May have made a
> mistake. At least I got the initial course right within a couple
> degrees. As an instructor told my class many years ago, the most
> important output from any nav system is "which way do we go".
Saiboat compasses are divided into 5 degree increments, sailing closer than
2.5d to that is guess work.
Dan Hogan WA6PBY
C27 "Gacha"
dhhogan1@XXX.XXX
Nav-L Page: http://www.wa6pby.com
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