From: Tom Sult
Date: 2017 Jan 03, 14:58 -0600
Tom Sult, MD
On Jan 3, 2017, at 13:48, Ron Jones <NoReply_RonJones@fer3.com> wrote:
Frank Reed, you wrote:
But for celestial observations, there is a certain historical insanity at work. To this day, navigators are taught to record their sights in zone time, presumably because time pieces were relatively rare decades ago, and it was difficult (expensive) to have a separate watch or device displaying UT. Or maybe it has been a long-lasting relic of the transition away from local mean time... There's no need for this practice today. We should record all sights in Universal Time. And we should train navigators to record sights in UT. It's more practical in every way that I can think of, and it eliminates an annoying source of error. Unfortunately, licensing exams are over-loaded with trick questions involving time zones and chronometers "reading" twelve hours from UT and so on. Licensing for celestial navigation has preserved obsolete techniques and turned them into exam games --a lazy means of spreading the grading curve-- in much the same way that lunars were used for exam games right up to the beginning of the 20th century, fifty years after they had ceased to be important at sea.
When I went through USAF Navigation Training for Pilots in 1958, before takeoff,we set our wrist watches to GMT and used GMT for all our 3 body (star) sight reductions, which were done using HO 249.