One of the most important buildings on your base is the hanger, this building is where you upgrade the AC-130 gunship and assign your troops. The AC-130 gunship can carry two weapons in the early stages of the game and that number will increase to three once you reach HQ level 5. Your troops are assigned in the hangar providing your hangar is at the required level, in the early stages of the game don't expect to have many at your disposal. Weapon upgrades are conducted at the hangar’s workshop.