High Quality Content by WIKIPEDIA articles! The Embraer KC-390 is a medium-size, twin-engine jet-powered military transport aircraft under development by Brazilian aerospace manufacturer Embraer. It is to perform aerial refueling, transport cargo and troops, and to receive fuel in-flight. It will be the heaviest aircraft that the company has made, and will be able to transport up to 21 tonnes (23 tons) of cargo, including wheeled armored vehicles.