OT (sort of) — My first course in navigation had something to do with the movement of stars, planets, the sun & moon, as well as how currents & tides would effect where you think you are or might be going; celestial navigation was a PITA. Then I got to flight school and the sextant was dropped in favor of TACAN, VOR and radar navigation. When I got to my first active duty squadron, the dedicated navigator still used a sextant on occasion just to keep his skills up, but Loran C & Omega were his primary inputs to the Litton LTN-51and later the LTN-72 Inertial navigation systems, but he also used radar. If we were close enough to have TACAN or VOR available, navigation was transferred to the pilots. Error with any of those systems was measured in miles and the INS drift was at times significant, but we never got lost.

I still own two sextants and take shots of the sun and moon using an artificial horizon, just to see how close I can get to the back yard. There are apps available to crunch the numbers and plot the lines of position — much nicer than 40 years ago. Still, error induced from the sextant sighting and errors in time are measured in miles, not feet. But for where & when you would use a sextant, a few miles is good enough.

12 years after I left my last squadron tour I bought my Garmin GPS V and I never looked back. Accuracy was typically about 20’, 12’ if the averaging mode was used. The US military invested so much in those systems, why not take advantage. My latest GPS is a Garmin Oregon 600 and I’ve never bothered to use its averaging function, it’ll get to 12’ accuracy easily without it. A few feet accuracy is not bad for something you can drop in your pocket.