I'm trying to create a battle in Sicily in July 1943, the night before operation Husky with airborne troops landing and securing some objectives. But I can't purchase any transport planes, so my airborne troops are eagles without wings

Can please someone tell me what I'm doing wrong?
Also is there a guide that tells you how to change visibility in order to represent night ( full moon, half moon... ), heavy rain, fog??
Thanks a lot
P.S. Which type of battle fits better a paratroop and conquer of objectives? Attack or meething engagment?