@Mazza
I went through the booklet and highlighted key points that I thought were important (acronyms, values like speed and flight level etc), then I rewrote the entire document in my own words.
I made it considerably shorter, though, by using dot points.
For the aircraft specifications I made flash cards and organised them into piles based on similar characteristics such as the routes they fly.
Rather than learning each individual aircraft, I can remember which aircraft goes in which group and I have a rough idea of the specifications of that particular aircraft.
Hope this helps!