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Hello esteemed members of this forum.
I heil from Southern Coastal Florida and I'm dusting off my Celestial Nav abilities to keep my brain going.
Merry XMass to all.
JP
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Ahoy shipmate! Welcome aboard!
We are all "learners" in celestial navigation and tryin' hard too.
I'm in New Jersey- just on the coast near Cape May and there's no snow.
A merry Christmas to you and your family as well!
Peace,
Craig
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12-25-2020, 01:29 PM
(This post was last modified: 12-25-2020, 01:56 PM by pabrides.)
Merry Christmas you scurvy dog.
Don't let the covid hoax dry up your nav skills.
Send me a sextant shot with a reasonable dr and ill try to find your location.
Here is my chart room:
Sun LL Dr N 10, E 124
Dec 21 2020
08 04 15 gmt
Ha 17 28.6
Sun LL
Dec 21 2020
05 42 50 gmt
Ha 44 58.4
Moon LL
Dec 24
14 38 15 gmt
Ha 43 39.5
Sun LL
Dec23
07 46 12 gmt
Ha 21 33.5
Have fun matee
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Exchanging sight looks like a fun activity:
All sight using artificial horizon at a DR of 26N, 80W. Sextant Error= 1.5'
Sun LL
Date 12/14/2020
Time: 14 11 44.9 gmt
Hs: 45ᵒ 45.5'
Sun LL
Date 12/14/2020
Time: 20:16:29hrs. gmt
Hs: 46ᵒ 54.5'
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Yeah, this is good. But my question is about your instrument error... is the 1.5 error on or off the arc?
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12-26-2020, 02:08 PM
(This post was last modified: 12-26-2020, 02:22 PM by pabrides.)
@steamburn.
Well, I worked your sun shots but without some info. I used -1.5 for IC thinking your positive 1.5 IE was on the scale.
Also I didnt discover your shots were artificial horizon until I worked gha and got hc at half of the elevation you gave. I didn't go back to rework your first sight but just halfed the ho I got.
The second sight I just neglected the IE altogether because I just didnt know if it was off or on the scale.
So with all this doubt I managed to come up with your fix however inaccurate.
Im thinking west palm beach area.
26 44 N
80 19.2 W
If im close- ok
If im way off just give me Ha, time, and date. you gave me Hs without much data - even your first shot gmt says 44.9 seconds... whatever that means. Then ill go at it again... this is fun
Cheers
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My Sextant Error is on the arc.
My exact coordinates are 26 42 11.7N, 80 14 29.5W.
Your calculation of my sights locates me only 4.58 NM away. That is about the same I got.
I calculated your position as 09 03N, 124 42.5E using only the Sun sights. I will do the Moon sight later on.
How bad did I do?
Regards,
JP
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12-26-2020, 06:04 PM
(This post was last modified: 12-26-2020, 06:11 PM by pabrides.)
You didnt do too bad.
My lat-long:
10 17.5N
123 57E
I should have given you a better pair of shots.
Hear are two sun shots that put me right on target.
Same DR 10N 124W
Sun LL Dec 25
GMT 23 52 19
Ha 23 45.2
Sun LL Dec 26
GMT 06 40 41
Ha 35 10.5
Most errors like watch error taken out already. Just add alt corr for Ho then work the books.
Remember that I'm in East longitude so you add AP Long to gha to get LHA.
Thanks for the practice. Next time I go someplace interesting ill send you some shots so you can guess where I went.. :) Before covid I'd take rides on ferrys just to get some actual CN experience under my belt. My wife thinks I'm a nut.
Cheers
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pabrides,
Are you using an AH in your observations above?
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12-27-2020, 03:40 AM
(This post was last modified: 12-27-2020, 03:48 AM by pabrides.)
In fact I did use an AH but as I said everything except altc has been taken care of. I didn't want you to get confused so I sent you the Ha which comes after the AH division by 2 and before the altc. Just use the numbers I gave you as if it was a straight horizon shot with no dip or IE. Maybe next time I'll send the raw data and let you work the reduction 100% if you prefer.