NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Sean C
Date: 2015 Nov 25, 22:59 -0800
John Brown Wrote:
In nav terms (r) represents distance, (theta) represents course
(x) represents dlat and (y) represents dep.
Examples are given in the instructions, together with the very few key presses needed to get results.
A separate calculation, division by cos lat, converts dep into dlon.
Cool! It took me a minute to wrap my head around this, but I get it now. I have a TI-30X IIs, which is very similar to your TI-30Xa.
So, using my previous example of starting at 37°N, 76°W on a course of 120° for 84NM, the solution using this calculator would go something like this:
[2nd] [R<>P] [>] [>] [Enter]
Display: P>Rx(
[8][4][2nd][,][1][2][0][)]
Display: P>Rx(84,120)
[Enter]
Display: -42
[/][6][0][STO>][Enter]
Display: Ans/60->A
-0.7
[2nd] [R<>P] [>] [>] [>] [Enter]
Display: P>Ry(
[8][4][2nd][,][1][2][0][)]
Display: P>Ry(84,120)
[Enter]
Display: 72.74613392
[/][cos][3][7][)][Enter]
Ans/cos(37)
Display: 91.08802827
[/][6][0][STO>][>][Enter]
Display: Ans/60->B
1.518133805
[3][7][+][MEMVAR][Enter][°'"][<][Enter][Enter]
Display: 36°18'0"
[-][7][6][+][MEMVAR][>][Enter][°'"][<][Enter][Enter]
Display: -74°28'54.7"
So, the answer is 36°18.0'N, 74°28.9'W...which agrees exactly with the result form the N.A. formulae. Neat! Thanks for explaining this.
And Sam, if you'd like me to explain this more, I'd be happy to via private email so as not to clutter NavList with more calculator nonsense. ;)
Regards,
Sean C.