I'm relatively certain the Apollo astronauts were still allowed to launch their rockets pointing upwards. I think most of our astronauts would have been smart enough to reorient a nav ball if they needed to. It's not like the stars move around much, even when you're in space. Quaternions make no intuitive sense whatsoever - they're effective enough running in the background of a program, but try sticking a 4-dimensional rotation system representing 3-dimensions onto some sort of nav-ball and your brain will go wonky. Better yet, try to write a roll, pitch, yaw algorithm sometime and find out how annoying gimbals really are. For the rest of you... here's Buzz Aldrin sitting in the cockpit of some spacecraft with a clearly visible nav ball: http://www.spaceflightnow.com/news/n0907/20apollo/07.jpg
