Air Canada Flight 759

Diagram of Runway 28R and Taxiway C at SFO. AC759 mistakenly lined up to land on Taxiway C, shown with the dotted blue line, instead of Runway 28R, shown with the dashed white line, before being ordered to abort the landing.

At 11:46 p.m. local time, Air Canada Flight 759, carrying 135 passengers and 5 crew members,[4] was cleared to land at SFO at Runway 28R. The adjacent Runway 28L had been closed at 10 p.m. local time and its lights were off,[6] except for a 20.5-foot-wide (6.2 m) lighted flashing "X" at the eastern runway threshold.[7] The captain was flying AC759 and the first officer was monitoring.[7] The two pilots of AC759 acknowledged that they mistook runway 28R for 28L and therefore lined up for landing on the parallel taxiway C,[2][7][8][9] even though runways and taxiways are lit with different colors and intensities.[6] It was not clear whether radio alignment signals were operating at the time.[10] Preliminary post-event investigation results noted that Runway 28R and Taxiway C were lit on default settings (in different colors), and the automatic terminal information service broadcast information was current and advised that 28L was closed and unlit.[7] According to preliminary Transportation Board investigation results, as the weather was clear, the pilot of AC759 was not required to activate the instrument landing system and relied instead on a visual approach, as typical for the prevailing conditions.[11]

Taxiway C already contained four airplanes, three from United Airlines and one from Philippine Airlines, queueing for takeoff.[1] At 11:55:46 p.m. local time, upon spotting aircraft lights approximately 0.7 miles (1.1 km) from the runway, the AC759 pilot asked the tower if he was clear to land on 28R, to which the air traffic controller responded at 11:55:56 p.m., "There's no one on 28R but you,"[1][3][12] when AC759 was approximately 0.3 miles (0.48 km) from the runway threshold.[13] The AC759 pilots "did not recall seeing aircraft on Taxiway C, but something did not look right to them" according to a post-incident interview summary.[7] The crew of Philippine Airlines 115 (PR115) turned on their landing lights to alert AC759 they were lined up on the taxiway.[14][13] The pilot of United Airlines 1 (UA001), the first in line for takeoff, interrupted the radio traffic at 11:56:01 p.m. and asked "Where is this guy going? He's on the taxiway."[1][3] The air traffic controller then ordered AC759 to abort the landing at 11:56:10 p.m. After AC759 acknowledged the go-around, the air traffic controller stated, "It looks like you were lined up for Charlie [Taxiway C] there."[1][3] AC759 had already started to climb before the go-around order.[13]

Afterwards, the pilot of UA001 radioed the tower saying, "Air Canada flew directly over us," and the air traffic controller responded, "Yeah, I saw that, guys."[1] During the first approach, AC759 flew for ¹⁄₄ mile (0.40 km) over Taxiway C, descended to an altitude as low as 81 feet (25 m) and approached as close as 29 feet (8.8 m) laterally to the four planes waiting on Taxiway C before being ordered to abort the landing.[12][15][16] According to the flight data recorder, the pilots advanced the thrust levers when AC759 was 85 feet (26 m) above the ground and the minimum altitude was 59 feet (18 m), approximately 2.5 seconds after the thrust levers had been advanced.[7] Following a reconstruction of events, one pilot not involved in the incident noted that had AC759 waited five more seconds before pulling up, it would have collided with the third plane (UAL 863) on the taxiway.[16] There was also less than 14 feet (4.3 m) separation between the bottom of the Air Canada aircraft and the tail of the Philippine Airlines A340.[17]

SFO was the first airport in the United States to install an Airport Surface Surveillance Capability (ASSC) system,[18] which should have alerted the tower of a potential conflict between runway and taxiway movements.[11] AC759 disappeared from the local controller's ASSC display for twelve seconds, between 11:55:52 and 11:56:04 p.m. local time (from shortly after the AC759 pilot asked for confirmation that 28R was clear, to the time the UA001 pilot noted that AC759 was lined up for Taxiway C), as AC759 was too far off-course from 28R.[13]

AC759 completed its go-around and landed without incident after the second approach.[1] A single air traffic controller was monitoring ground and tower frequencies, which would typically be handled by two controllers.[11][13]

The aircraft flying AC759 that night was C-FKCK, an Airbus A320-200.[12][19] The aircraft was 24.5 years old on the day of the incident, first flying in December 1992.[20]

The incident was not considered reportable under current federal regulations,[22] but former NTSB chairman Jim Hall called it "the most significant near-miss we've had in this decade" and urged the NTSB to re-evaluate those reporting requirements.[23] The United States National Transportation Safety Board (NTSB) was informed of the incident on July 9, and took the lead on the investigation, with assistance from the Federal Aviation Administration (FAA). The Transportation Safety Board of Canada (TSB) served as a facilitator to convey information between Air Canada and the NTSB.[4] TSB released preliminary information from Occurrence No. A17F0159 on July 11, 2017.[12][19] NTSB assigned identification number DCA17IA148 to the incident.[24]

A retired pilot stated that SFO requires "precision flying" as the two runways (28R and 28L) are laterally separated by 750 feet (230 m), and Taxiway C is separated from 28R by less than 500 feet (150 m).[10] Other pilots pointed out that some airlines require all aircraft to use the instrument landing system (ILS) regardless of weather or visibility, which could have alerted the cockpit that the aircraft was lined up with the taxiway.[2] Dave Jones, then California Insurance Commissioner and a passenger on AC759, wrote a letter to Air Canada a week after the incident requesting their cooperation with the investigation.[6][16]

Preliminary NTSB investigation results from flight data recorder telemetry, released on August 2, 2017, indicate that AC759 reached a minimum altitude of 59 feet (18 m) above ground level, comparable to the 55 ft 10 in (17.02 m) tail height of a Boeing 787-9, two of which were on Taxiway C.[7][25] The cockpit voice recorder had been overwritten before the investigation was launched,[13] as C-FKCK flew three more flights on July 8 before the NTSB was informed of the near-miss on July 9.[23]

Following the incident, in early August the Federal Aviation Administration modified nighttime landing procedures at SFO, forbidding visual approaches at night "when an adjacent parallel runway is closed" and replacing them with instrument approaches, either ILS or satellite-based, and requiring two air traffic controllers in the control tower "until the late-night arrival rush is over".[30]

Air Canada has stopped using flight number 759.[31]

• Continental Airlines Flight 1883 – a similar incident that involved an aircraft landing on a taxiway
• China Eastern Airlines Flight 5106 near collision upon takeoff after ignoring control tower.
• LAX runway collision: USAir Flight 1493 & SkyWest Flight 5569
• Linate Airport runway collision: SAS Flight 686 & Air Evex Cessna Citation
• Accidents and incidents involving the Airbus A320 family

• How a tired Air Canada pilot narrowly avoided a massive plane crash. CBC News. May 3, 2018.

Wikimedia Commons has media related to Air Canada Flight 759.

• "SFO ATC audio recording". July 7, 2017.
• "Near Midair Collision on approach to San Francisco International Airport". Accident Investigations, DCA17IA148. National Transportation Safety Board. August 2, 2017.
• NTSB (May 2, 2018). San Francisco International Airport Terminal 2 security camera video of the July 7, 2017, Air Canada taxiway overflight – via YouTube.
• Simon Hradecky (October 12, 2018). "Incident: Canada A320 at San Francisco on Jul 7th 2017, lined up with taxiway for landing". Aviation Herald.
• Richard N. Aarons (November 26, 2018). "A Near Catastrophe: Within Feet Of Becoming The Worst Air Disaster". Business & Commercial Aviation.