The medical workers of a medical flight service company board a "patient" onto the jet during a drilling at Tianjin Binhai International Airport, north China's Tianjin Municipality, Feb. 9, 2010. A type of air ambulance service has come into operation recently in Tianjin and provides professional flight transport and nursing services to critical patients with respirators, monitors, stretchers, lox bottles etc. equipped on the jet. [Xinhua]