??Porter airlines. (Photo: people.com.cn)

??ASTRA. (Photo: people.com.cn)

??Swiss international airlines.(Photo: people.com.cn)

??Air Berlin .(Photo: people.com.cn)

??lufthansa.(Photo: people.com.cn)

??Sichuan Airlines. (Photo: people.com.cn)

??China Southern Airlines. (Photo: people.com.cn)

??Hong Kong Airline. (Photo: people.com.cn)

??Royal Brunei. (Photo: people.com.cn)

??Brussels Airlines.(Photo: people.com.cn)

??Wizz Air.(Photo: people.com.cn)

??Air France.(Photo: people.com.cn)

??Martinair.(Photo: people.com.cn)

??Australian Airlines.(Photo: people.com.cn)

??Royal Jordanian Airlines.(Photo: people.com.cn)