In the northern hemisphere a great circle route between two points with the 
same latitude will be north of the parallel, so if the latitudes are close, the 
great circle will arch above the straight line (for most map projections that 
keep “parallels” parallel). A gnomonic projection of the world centered on 
Charlotte or Honolulu would show the great circle route as a straight line. I’m 
sure none of those were printed, but I thought I might find a site that allowed 
the user to select a tangent point (Charlotte or Honolulu) and then show the 
map. The closest I got was https://bl.ocks.org/mbostock/3795048 and 
https://observablehq.com/@d3/gnomonic . It turns out that d3.js, a graphics 
library has a function geoGnomonic().

—Barry

Sent from my iPad

> On Sep 19, 2021, at 3:50 PM, Frank Wimberly <wimber...@gmail.com> wrote:
> 
> Not to change the subject but...
> 
> A large airliner recently, 15 minutes ago, flew over Santa Fe headed west.  
> My Flight Radar app tells me that it's a Boeing 777 going from Charlotte to 
> Honolulu at an altitude of 38000 feet.  I wouldn't have thought that Santa Fe 
> was on a great Circle route between those two cities.  But maybe it is.
> 
> ---
> Frank C. Wimberly
> 140 Calle Ojo Feliz, 
> Santa Fe, NM 87505
> 
> 505 670-9918
> Santa Fe, NM
> 
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