On August 16, 2008, at 0150 Pacific daylight time, Eva Air 17, Taiwanese registry B16710, a Boeing 777-300, was being pushed back from the gate when a mechanic was pinned under the left nose gear at San Francisco International Airport, San Francisco, California. The flight crew and passengers were not injured; the mechanic sustained serious injuries. There was no damage to the airplane. Eva Air was operating the airplane under the provisions of 14 Code of Federal Regulations Part 129. The scheduled international passenger flight was destined for Taoyuan International Airport, Taipei, Taiwan. Visual meteorological conditions prevailed and an instrument flight plan was filed. According to airport operations personnel, an Eva Air mechanic and a Swissport ground agent were pushing the flight back from the gate. The ground agent reported that the mechanic had difficulty unhooking the tow bar from the airplane and began jumping on it and standing in front of the nose gear. When the tow bar fell, the airplane lurched forward and pinned the mechanic under the left nose gear. In a written statement submitted by flight crew personnel, they stated that the airplane was pushed back and the engines were started. The flight crew instructed the ground handling crew to disconnect the tow bar and advise when they were clear to taxi. The ground crew had difficulty removing the tow bar and advised that they intended to straighten the airplane by towing it forward in order to release the tow bar. The ground crew instructed the flight crew to release the parking break and the airplane rolled over the mechanic. The Eva Air mechanic reported that normally, ground agents handle the pushback. The ground agent had difficulty unhooking the tow bar from the airplane. Due to this difficulty, the mechanic came to assist and then suggested that the airplane be towed forward to straighten the airplane and tug. The ground agent then requested that the pilot release the parking brake. The airplane was towed forward, and the ground agent attempted to disconnect the tow bar; however, he still had difficulty. The ground agent went to the tug and the mechanic came to check the condition of the tow bar which he reported was half unhooked. The mechanic tried to disconnect the tow bar by stepping on it, it eventually disconnected from the airplane, and the airplane began to roll forward. The mechanic shouted to the ground agent to "set the parking brake" and then the mechanic fell on the ground. The airplane continued to roll forward and pinned the mechanic's leg. The mechanic reported that the normal procedure of disconnecting a tow bar requires that the parking brake be set, chocks are in, tug disconnected from the tow bar, and then the tow bar disconnected from the airplane. The Swissport Station Manager and Eva Air personnel indicated that the ground handling of the airplane was not in accordance with established standard operating procedures. Normal procedure requires that the parking brake be set, prior to removal of the tow bar.