Meteorologists!!!!! They were able to predict the winds aloft, which was pretty darn accurate, predicated on what they knew at the time.
Here is what the pilots had to use - which again was pretty accurate. For the bigger planes, they had a navigator whose sole job was to give the pilots this information.
View attachment 536701
Here is an overview
I would think they would take a couple of sights on almost every flight just to stay qualified.Would not want to be a bad guy with that thing creating a shadow in the moonlight.
My neighbors for a while, were USN C-130 (VXE-6) pilots that would fly down to Antarctica. Got a chance to tour the plane and started to geek out on some of the equipment they had in the navigators bay.... The one cool thing was the unit called a NAVSTAR - early GPS, wow, some pretty heady stuff back then. Their planes had a portal on top so they could use a sextant if needed.
My wife talks about being the car with the Colonel and the guys at the gates always had to salute, made her feel proud of her dad. Says it kind of made up for base housing they had to live in. When the Colonel was stationed at the Pentagon she says his office had huge combination lock dials built into the doors.