NavList:

Dear Greg,

Thank you very much for publishing your beautiful Ex-Meridian Exercise. The Horizon is DEFINITELY SUPERB !!!

Awaiting other Colleagues' results - Peter, Andres, and Jeremy in particular :-) - and just for the fun of it, I chose to "number-crunch" your Ex-Meridian example without recourse to the magic tables found in Bowditch, (or their French Counterparts)

1 - Treating it as a standard LAN - i.e. no previously known position - I am getting the following results :
Local Time of Sun Transit : 11h58m02.3s
Observer's Position at LTT : N34°10'2 W119°13'1, a position which falls within 0.8 NM from your GPS and Chart Fixes.
Observed SD : 0.2 NM (which is EXCELLENT !)
Estimated Longitude Error : 0.9' (one sigma)

2 - Treating it as a standard FIX - with NO previously known position - , get the following results :
2.1 - If you use observations #1 and #5, get the following possible approximate positions : S8027.0W13337.0 and N3401.1W11922.1 ... difficult guessing choice indeed !!!
2.2 - If you use observations #1, #4 and #5, get the following VERY ROUGH position N2525.4W11938.8 which after one iteration becomes N3410.4W11922.1 and from this latter position get the following Intercepts/Azimuts:

#1 1.4 NM / 172°2
#2 1.5 NM / 172°6
#3 0.9 NM / 173°0
#4 0.8 NM / 173°4
#5 0.3 NM / 179°8

From these LOP's derive the following "Symmedian point" being in Azimut 092° and at a distance of 7.4 NM from your (N3410.4W11922.1) Estimate/DR,

and finally get :
- SD for all observations equal to 0.2 NM , and
- observed position at LT = 11h58m02.3s : N34°10'2 W119°13'1 , i.e.
- exactly all the same results here than for the LAN.

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Dear Greag,

again your set of observations is absolutely SUPERB, and you observed right from a height (17 ft) which is a very good trade off to still offer a clear/sharp horizon (generally "the lower the better" here) while being sufficient to dim out most of the waves/swell induced horizon irregularities (generally "the higher the better" here).

Best Admiring Friendly Regards,

HAPPY NEW YEAR 2011

Kermit

Antoine M. "Kermit" Couëtte
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