Which airline code is Hu?

Hainan Airlines Holding Co., Ltd. is the representative of aviation code, and Hu is Hainan Airlines Holding Co., Ltd., which belongs to IATA code of International Air Transport Association. HNA is the first "SKYTRAX five-star" airline in Chinese mainland, and has established aviation operation bases/branches in 24 cities including Beijing, Shanghai, Shenzhen and Guangzhou.