On July 7, 2017, an Airbus A320-211 operating as Air Canada Flight 759 was nearly involved in an accident at San Francisco International Airport in San Mateo County, California, United States. The flight, which originated at Toronto Pearson International Airport, had been cleared by air traffic control to land on runway 28R and was on final approach to land on that runway; however, instead of lining up with the runway, the aircraft had lined up with the parallel taxiway, on which four fully loaded and fueled passenger airplanes were stopped awaiting takeoff clearance. The flight crew initiated a go-around prior to landing, after which it landed on 28R without further incident. The aircraft on the taxiway departed for their intended destinations without further incident. The subsequent investigation by the National Transportation Safety Board (NTSB) determined that the Air Canada airplane descended to 59 feet (18 m) above the ground before it began its climb, and that it missed colliding with one of the aircraft on the taxiway by 14 feet (4.3 m).

Robert Llewellyn Sumwalt III is an American academic, aviator, government official and writer. He was a board member of the National Transportation Safety Board for over 15 years, from August 2006 to June 30, 2021, serving as the agency's chairman from 2017 to 2021. He currently serves as the executive director of Embry-Riddle's Boeing Center for Aviation and Aerospace Safety.