The Kangzang Plateau is known as the "roof of the world", with an average elevation of more than 4,000 meters. The mountains are covered with snow all year round, filled with mist and changeable climate. In order to open up the air route here and carry out the airdrop mission, we must overcome the harsh natural climate conditions. Therefore, based on the actual difficulties, combined with the aircraft situation and the characteristics of plateau flight, the air transport team put forward the methods of step-by-step test flight, step-by-step route extension and step-by-step propulsion to complete the airdrop mission.