Two passenger-grade autonomous aerial vehicles (AAV) from EHang, a leading AAV technology platform company, take demo flights in an integrated airspace in Shenzhen, south China's Guangdong Province, Sept. 15, 2021. EHang and HELI-EASTERN held a joint press conference Wednesday on building a pilot project focusing on integrated airspace for urban air mobility operations in the Guangdong-Hong Kong-Macao Greater Bay Area. (Xinhua/Mao Siqian)