Air Canada probed after blunder at SFO
Federal investigators are probing why an Air Canada flight crew did not hear repeated warnings from air traffic controllers to abort a landing at San Francisco International Airport on Sunday night, less than four months after a nearmiss landing at SFO by a jet from the same airline.
Air Canada Flight 781, an Airbus A320, landed safely on Runway 28R at 9:26 p.m., despite air traffic controllers not being sure the runway was clear for landing, Ian Gregor, a spokesman for the Federal Aviation Administration, said Tuesday.
“Air Canada, go around. Air Canada, go around,” an air traffic controller repeatedly commanded without getting a response from the cockpit of the arriving flight from Montreal until after it touched down on the runway.
After landing, the crew told the tower they had a radio problem, Gregor said.
“That’s pretty evident,” an air traffic controller told the crew before providing instructions on where to taxi.
A supervisor at an airport tower had cleared the plane for landing at the same runway when it was 6 miles away from the airport, but then changed instructions because it was not clear the runway would be free, officials said.
“The tower controller subsequently instructed the Air Canada crew multiple times to execute a go-around because he was not certain that a preceding arrival would be completely clear of the runway before the Air Canada jet reached the runway threshold,” Gregor said in a statement.
An air traffic controller repeats “Canada 781 go around” at least six times, according to a public radio transmission of the incident listened to by The Chronicle.
When the commands went unanswered, the traffic controller used a flashing red light gun to alert the crew to go around, which officials said is standard protocol for an unresponsive air crew. The move also failed to get the crew’s attention.
The Air Canada plane still landed on the runway, but a radar replay showed the runway had been clear for landing and the aircraft did not come close to hitting planes, Gregor said.
Air Canada said in a statement Tuesday the crew did not receive any of the dispatches from the tower controller and that the airline is “investigating the circumstances.”
“After receiving proper clearance to land it proceeded to do so and landed normally,” the airline said Tuesday morning. “Upon landing the crew was informed the tower had attempted unsuccessfully to contact the aircraft, however the message was not received by the crew.”
San Francisco International Airport officials declined to comment on the incident.
It would be an extremely rare occurrence if the investigation found there was a radio communication glitch because Airbus A320 planes tend to have reliable devices and have two additional radios aboard in case one doesn’t work, said Ross Aimer, a retired United Airlines pilot and CEO of Aero Consulting Experts.
Constant communication with air traffic controllers is a must for pilots, Aimer said. Going “nordo,” which means having no radio communication for an extended period, should have raised alarms with the pilot, he said.
“Any pilot, myself included, if I don’t hear anything for more than 30 seconds I know there’s something wrong,” Aimer said. “These guys, they basically went five minutes nordo. It didn’t dawn on them there’s something wrong. I don’t understand.”
It was more understandable the crew missed the red light gun, Aimer said. Most pilots don’t look at the towers during a landing, and the communication method is “kind of an old-fashioned last-resort thing from the World War II era” that’s hardly used.
Kit Darby, an aviation consultant from Atlanta, said the few facts available suggest the pilot changed to the wrong frequency after he was initially cleared to land.
“Sounds like he had a bad radio — which is very rare — or a mistuned frequency, which would be quite common,” Darby said Tuesday.
Multiple investigations were opened in July when another arriving Air Canada flight came within 100 feet of hitting two commercial planes lined up on a taxiway. The aircraft, an Airbus A320 with 140 people aboard, was mistakenly approaching Taxiway C instead of the adjacent runway when the pilot was ordered to pull out of the landing, according to a preliminary investigation from the Transportation Safety Board of Canada.
A pilot had been cleared to land on Runway 28 Right, the same runway the Sunday night flight landed on, but was instructed to abort the landing when the plane neared departing flights on the taxiway.
In that incident, radio transmissions from the tower recorded a voice saying, “Where is this guy going? He’s on the taxiway,” before asking the pilot to perform a go-around. The pilot followed orders and landed the plane safely.
That incident prompted new policies at San Francisco International Airport. Since then, pilots landing at night must perform an instrument landing — using the runway’s advanced guidance systems — when a parallel runway is closed. Aviation officials also required two air traffic controllers to be on duty through the late-night arrival rush.
“Any included, pilot, if myselfI don’t hear anything for more than 30 seconds I know there’s something wrong. These guys, they basically went five minutes nordo. It didn’t dawn on them there’s something wrong. I don’t understand.” Ross Aimer, CEO, Aero Consulting Experts, on pilots with no radio communication