NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Obtain a fix when you don't have an clear AP?
From: Peter Hakel
Date: 2015 Jan 10, 02:12 +0000
From: Stan K <NoReply_StanK@fer3.com>
To: pmh099@yahoo.com
Sent: Friday, January 9, 2015 3:16 PM
Subject: [NavList] Re: Obtain a fix when you don't have an clear AP?
From: Peter Hakel
Date: 2015 Jan 10, 02:12 +0000
I did this exercise 4 years ago and whatever I got with Excel was within 1/2 mile according to the author's comment below the video. I don’t recall the details, but Seattle sounds right.
Peter Hakel
Peter Hakel
From: Stan K <NoReply_StanK@fer3.com>
To: pmh099@yahoo.com
Sent: Friday, January 9, 2015 3:16 PM
Subject: [NavList] Re: Obtain a fix when you don't have an clear AP?
Where can I find the correct answer? Using Celestial Tools iteratively, I get 47º29.0'N, 122º13.9'W. 8055 S Langston Rd, Seattle, WA.
-----Original Message-----
From: Samuel L <NoReply_SamuelL@fer3.com>
To: slk1000 <slk1000---.com>
Sent: Fri, Jan 9, 2015 2:26 am
Subject: [NavList] Obtain a fix when you don't have an clear AP?
From: Samuel L <NoReply_SamuelL@fer3.com>
To: slk1000 <slk1000---.com>
Sent: Fri, Jan 9, 2015 2:26 am
Subject: [NavList] Obtain a fix when you don't have an clear AP?
There's a youtube video of a man taking 2 Sun sights and asking you to figure out where he's located. Greg got it correct (as you can read in the comments section of the video) using, I assume, his Palm (Pilot?) with Pilot Navigator Version 6.9.
The time WWV signals are very heard hear and the guy makes little effort to provide you with time or Hs- in other words his presentation is sloppy.
What I'm trying to figure out is how you get a position fix when you don't have an obvious Ap Latitude or Ap Longitude? And, I can't plot an intercept that's many hundreds of miles away on a UPS. However, I did figure out the time and Hs of both sights and using Peter Hakel's Lop.xls a fix was obtained. But I'd like to know how to do it on paper either by adjusting the Ap Longitude and resulting LHA which I suppose is the only thing you can adjust. I'm no expert in these matters.
Link to the video- https://www.youtube.com/watch?v=W-SkC3xwE7o
An AH was used in both shots.
Here are the particulars from the video-
1rst shot Date- 2/20/2010
Time- 17:26:26 UTC
Hs- 40d 18.2min
Limb observed- Upper Limb
My determinations-
GHA 78d 11min
Declination- S 10d 46.4min
Ho- 19d 50.5min
2nd shot Date- 2/21/2010
Time- 00:16:02 UTC
Hs- 24d 04.4 min
Limb observed- Lower Limb
My determinations-
GHA 180d 35.5min
Declination- S 10d 40.3min
Ho- 12d 14.1min
Using Peter Hakel's LOP.xls the following fix was obtained-
N 47d 28.8min
W 122d 13.9min
Thanks,
Sam L.
