Originally Posted by
megan
Both the technology failure and rescue stories are remarkable in their own way, though I would emphasise the difference between being 'lost' with no idea where you are, and 'exact' navigation to within a ship's length, as implied by the original story at the start of this thread.
Another concept that comes to mind is the use of daylight tracking to geolocate lightweight animal tags (without GPS). Automatic measurements of length of day, and time of local noon (along with an on-board clock and some processing power), are generally sufficient to estimate latitude and longitude respectively, and track migrations over vast distances:
Animal Migration Research, Jeff Kelly Lab
As one reference humorously states: It is difficult to persuade an animal to carry out a daily sextant observation!
Edit: This article implies that the claimed accuracy of Capt Vette's solar navigation and VHF 'boxing' was about as mythical as Mark Twain, though his role in the rescue was indeed honourable:
http://www.navworld.com/navcerebrations/mayday.htm
Next Vette instructed Prochnow to determine the elevation angle of the Sun above the horizon using his partially outstretched arm and fingers as a sextant. Prochnow established the elevation of the Sun as four fingers as Vette measured the elevation of the Sun as two fingers. Vette estimated the Cessna was about 240-250 nmi (each finger was slightly more than 2 degrees with each degree worth 60 nmi) from the DC-10.