Comment Re:Navigation at sea (Score 1) 260
You *do* realize there were lots of radionavigation aids before GPS ?
http://en.wikipedia.org/wiki/LORAN
http://en.wikipedia.org/wiki/Decca_Navigator_System
They have been/are being shut down but the time of sextant-only navigation is long past.
Besides, there is always the possibility of using radar to map the coastline (if you're close enough).