Two United Airlines Boeing 777s collided on ground at San Francisco International Airport.
Two Boeing 777clipped wingtips while taxiing at at San Francisco International Airport.
The incident occurred during the pushback of one aircraft from Terminal 2, Gate 6, while the other was taxiing nearby. The wingtips of both planes made contact, resulting in visible damage to both aircraft.

The Boeing 777-300ER with registration N2645U was heading to Hong Kong as flight UA877 and the other 777-300ER with registration N2747U was heading to Sydney as flight UA863.
Both flights were canceled. The airline said : ‘we needed to take the planes out of service to address a technical issue’.