The Aviationist Quiz Pt. 2

The first round of our contest (the warm up question) ends today. We have a new challenge question for you to answer; before proceding with the new questions please consider that at the end of this series of questions, we will evaluate the winners based on:
1. Completeness of answers
2. Partecipation in every round

So keep playing with us!

And now, do you think you know the answer to answer to this one? Comment here!