<p>There a bit of history to this that can be found in different places on the net. First, remember that from the 50-60’s, the Air Force did most of our space research and was the lead in military efforts in space. When JFK moved to de-militarize space and created NASA; which took over many of the USAF space projects while cancelling others such as the MOL. Two things quietly occured; first, the Air Force was a bit bitter by this action and didn’t support the initial efforts of NASA; while the Air Force allowing many who were already working on projects with NASA, they re-assigned many others who where working on pure military programs back to USAF research and testing. </p>
<p>Second, This opened the door for the Navy to quickly allow their pilots to apply for slots when they had few opportunities when the Air Force had space research. Under NASA, the USAF made it a bit more difficult as AF pilots first had to complete advanced test pilot training as a prerequisite for AF approval while Navy pilots did not have such a requirement to apply. It didn’t hurt that some of the directors at NASA were former Navy admirals. This has been because NASA is a non-military organization. Keep in mind that Marine astronauts are counted as Navy for these numbers.</p>
<p>There is some solace for Air Force supporters in that the atronaut numbers are just about equal now and that control of space defense has slowly been shifted to all Air Force; almost all Naval space systems and satellites have been transferred over to the Air Force as the Air Force has been designated the official military agent in space (i.e. Naval Space Command has 350 people, Air Force Space Command has 37,000 people).</p>