Several passengers and crew members aboard an overnight transatlantic Air Canada flight were injured after a sleepy pilot mistakenly thought the plane was about to collide with a U.S. military jet and forced the Boeing 767 into a sharp dive.
A new report by Canada’s Transportation Safety Board attributes the 46-second incident, which occurred in January, to pilot fatigue and specifically to “sleep inertia,” a state in which performance and situational awareness are degraded immediately after waking up. The pilot had been asleep for about 75 minutes during a required rest period implemented by regulators as a measure to combat pilot fatigue.
According to the Transportation Safety Board’s report, the pilot was awakened unintentionally by the captain reporting on the plane’s position. At the same time, a U.S. Air Force plane was approaching about 300 yards below, setting off cockpit alerts, which the captain mentioned to the just-awakened first officer (FO).
“The FO initially mistook the planet Venus for an aircraft but the captain advised again that the target was at the 12 o’clock position (straight ahead) and 1000 feet below,” the report stated.
“When the FO saw the oncoming aircraft, the FO interpreted its position as being above and descending towards them. The FO reacted to the perceived imminent collision by pushing forward on the control column,” the report explained.
The plane abruptly dove about 400 feet before the captain took the control column and pulled it back up. Fourteen passengers and two crew members, all unbelted, were slammed into various parts of the plane, receiving cuts and bruises. Eight of the injured were treated at a hospital in Switzerland upon landing in Zurich three hours after the incident. There were 95 passengers and 8 crew members on the plane.
The report also explained that the first officer had young children who often interrupted his sleep at home, which could explain why he napped for 75 minutes instead of the 40-minute maximum. The extra time allowed the pilot to fall into a deep sleep, which made him more disoriented upon wakening.
In a statement about the incident, lead investigator John Lee said “This occurrence underscores the challenge of managing fatigue on the flight deck.”
Air Canada said that it has taken measures to prevent a recurrence, including reminding pilots about the importance of adhering to in-flight napping rules and raising awareness about fatigue and its effects among flight crew.
The airline also reported that it has established a non-punitive fatigue reporting system that will allow pilots to rearrange assignments when they are too tired to fly. That system, which is expected to go into effect this summer, should provide some long-awaited relief to Canadian pilots, who have pressured regulators there to consider the special stresses of night flying when developing regulations.