The U.S. National Transportation Safety Board has identified pilot error as the probable cause of the July 7, 2017 incident in which the flight crew of an Air Canada Airbus A320 mistook a taxiway for a runway at San Francisco International Airport and nearly crashed into four other airliners on the ground. The NTSB said the mistake resulted from the crewmembers’ lack of awareness of the parallel runway closure due to their ineffective review of notice to airmen (Notam) information before the flight and during the approach briefing.
The Board named as contributing factors the flight crew’s failure to tune the instrument landing system frequency for backup lateral guidance, “expectation bias,” fatigue due to circadian disruption and length of continued wakefulness, and breakdowns in crew resource management. It also faulted Air Canada’s ineffective presentation of approach procedure and Notam information. The flight originated at Toronto Pearson International airport and night visual meteorological conditions prevailed.
On the night of the incident, at 11:56 p.m. local time, air traffic control cleared the A320 to land on SFO’s Runway 28R, but the pilots instead lined up with parallel Taxiway C. Two Boeing 787s, an Airbus A340, and a Boeing 737 sat on Taxiway C awaiting clearance to take off from Runway 28R. The A320 descended to an altitude of 100 feet agl and overflew the first airplane on the taxiway. The flight crew initiated a go-around, and the airplane reached a minimum altitude of about 60 feet and overflew the second airplane on the taxiway before starting to climb.
SFO had closed Runway 28 Left for construction at the time, and several indications of that fact included a lighted X and an Automatic Terminal Information Service (ATIS) message noting the runway’s lights were not illuminated. According to the NTSB, both the taxiway and the active runway were illuminated on “default settings,” including green centerline and blue edge lights on the taxiway, as well as white centerline and touchdown zone lights and green threshold and edge lights on the runway’s approach end.
None of the five flight crewmembers and 135 passengers aboard the incident airplane suffered injuries.