While it might not be comforting to the average flyer, the reality is that most air incidents are due to pilot error. In the last 20 years, around 85 per cent of aviation accidents have been caused by “pilot error”, according to the National Transportation Board.
In this case, the airport’s surrounding geography could have played a role, says Greg McConnell, with the Canadian Federal Pilots Association.
Although runways and taxiways are marked very differently, it can be difficult landing an aircraft at night in San Francisco, said McConnell.
“I have flown into San Francisco at night,” he said. “It can be tricky doing a visual approach at night.”
The Air Canada plane from Toronto was carrying 135 passengers and was given clearance to land on a runway just before midnight. Instead, the plane positioned itself to land on the parallel taxiway, which had four aircraft with passengers that were waiting for departure, according to the FAA.
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When an air traffic controller realized the plane was headed for the taxiway, he told the pilot to abort the landing attempt and try again.
“It could have had serious repercussions,” McConnell said. “There were a number of aircrafts on the taxiway, who had lights on. Clearly, there must have been a near miss.”
“It could have been catastrophic.”
Taxiways ‘clearly marked’
Taxiways are essentially roads pilots use to drive aircraft between the terminal and their points for takeoff and landing.
“They are marked very differently than runways,” McConnell said.
For night operations (like the Air Canada flight into San Francisco) taxiways and runways are equipped with edge lights to help with visibility.
The taxiway edge lights emit a blue light, while the runway edge has white “lead lights,” McConnell said.
However, he said the blue lights aren’t as bright as the runway lights and can be tricky to see at night.
McConnell added the San Francisco airport can be difficult to land in because of its mountainous terrain and the fact that it’s surrounded by water.
“It can be tricky doing a visual approach at night there, and it can be like a dark hole you are looking at. It’s harder to see the taxiway lights at night than during the day,” he said.
A visual approach landing is when the pilot uses visual references and the weather is typically clear of clouds, he said. Another way to land is using the “instrument” approach. This method is used when pilots can’t get a visual contact of the runway and use transmitted radio signals instead.
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“There are too many questions with this near-miss disaster,” McConnell said. “I don’t know what happened and I don’t know what Air Canada’s training practices are. The FAA will look into it.”
The FAA and Air Canada said they are investigating the incident.
Global News reached out to the San Francisco International Airport but did not hear back.