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JCA:

I computed LAN= 12h 9m 42s by the equation of time method. What am I doing
wrong?

On 2008 May 16 meridian passage is 11h 56m and ET 12h is 3m 38s.
Subtracting ET from GMP I get 11h 52m 22s.

For Long 145d 40m E (-9h 42.6m) I get LMP 2h 9m 42s GMT.

For Zone -10 this becomes 12h 9m 42s.

My other results are

Az=0
Ho= 86d 5.8m
Hc= 86d 4.2m
1.6 toward
Lat= Dec-(90-Ho)= (19d 9.6m) - (3d 54.2m) = 15d 15.4m N

John Cole

> From: Anabasis 
> Reply-To: 
> Date: Fri, 16 May 2008 00:58:46 -0700 (PDT)
> To: NavList 
> Subject: [NavList 5012] Navigation exercise
>
>
> Hello Navigators,
>
> I am currently on a ship and was wondering if the members of the board
> would
>  like some real-life sights to work out?  I will supply the data and
> then people
> can run the numbers using whatever method and post results.
>
> Here is one from today, and it's a simple LAN problem.
>
> A ship is adrift near the island of Saipan, in the north Pacific.  The
> noon position
> is Lat 15-14'N and Long is 145-40'E on 5/16/08 (ZD -10)
>
> A) Calculate time of LAN, Az of the sun, and approximate Hc.
>
> A sight of the sun (LL) is observed at 1213-40L. Sextant altitude was
> 85-59.0'.  Height of eye was 106 ft, IE is 0.8' off the arc.  Temp was
> 93 deg F Barometer was 1012 MB.
>
> B) Determine Latitude by LAN.
>
> JCA
> >




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