A ground crew member checks the ARJ21-700 jet after a demonstration flight in Xi'an, capital city of northwest China's Shaanxi Province, July 17, 2015. The ARJ21, short for Advanced Regional Jet for the 21st Century, is a type of regional airliner designed and manufactured by the Commercial Aircraft Corporation of China (COMAC). Over twenty representatives were invited on Friday to experience the one-hour demonstration flight and give feedbacks so as to help improve the overall performance of the jet. (Xinhua/Li Yibo)