An investigation is underway into a near miss by an Air Canada plane last week at San Francisco airport that could have been a major catastrophe.
An Air Canada Airbus A320 was cleared to land on one of the runways when the pilot inadvertently lined up instead for a taxiway which runs parallel to the runway.
According to the U.S. Federal Aviation Authority four aircraft, fully loaded with passengers, were lined up on the taxiway waiting for departure when the incident occurred.
An air traffic controller became aware of the problem and sent the Air Canada plane on a "go around", which is an unusual event where pilots have to pull up and circle around to attempt the landing again.
FAA investigators are looking into how close the Air Canada aircraft came to landing and crashing into the four aircraft.
Retired United Airlines Captain Ross Aimer, CEO of Aero Consulting Experts, told Fairfax Media,the incident came close to what would have been the greatest aviation disaster in history.
"If you could imagine an Airbus colliding with four passenger aircraft full of fuel and passengers, then you can imagine how horrific this could have been." Aimer said.
Luckily, the plane landed without incident but now the investigation will focus on the distance between the Air Canada aircraft and the jets that were lined up on the taxiway.
There were 135 passengers and five crew members on board the Air Canada flight.
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