|An Air Canada jet arrives in Ottawa in this file photo. (DARREN BROWN/QMI Agency)
An Air Canada pilot initially mistook the planet Venus for an aircraft when he awoke from a nap and then sent the plane into a nosedive to avoid what he thought was an oncoming plane, a report said.
Fourteen passengers and two crew members not wearing seatbelts were injured when the Air Canada Boeing 767 made a sudden descent in January 2011 on an overnight flight from Toronto to Zurich, Switzerland.
The sleepy first officer initially thought Venus was an aircraft and then sharply nosedived to avoid what he thought was a plane heading straight for them, the Transportation Safety Board (TSB) report released Monday stated.
"The captain made a position report, causing the first officer to wake up. At roughly the same time, another aircraft was approaching from the opposite direction a thousand feet below," reads the report.
"The captain, who was the pilot in control of the aircraft, had visual contact with the oncoming aircraft. Under the effects of significant sleep inertia - when performance and situational awareness are degraded immediately after waking up - the first officer perceived the oncoming aircraft as being on a collision course and began a descent to avoid it."
The TSB notes that mid-flight naps are not unusual for pilots. It's called a "controlled rest period" and is a "common method of combating fatigue where one flight crew member takes short naps at certain times during a flight."
But the first officer was too fatigued to fly to begin with, napped at the wrong time and for too long, and didn't follow proper controlled rest procedures, the report notes.
"The first officer's level of sleep inertia was magnified by prior fatigue. Also contributing to the significant sleep inertia was napping during a period of the night that made deep sleep more likely, and napping longer than allowed by the company's controlled rest procedure," reads the report.
"The investigation also found that crews did not fully understand the risks associated with fatigue or the procedures for conducting controlled rest."
Air Canada and its pilots' union have since taken measures to make sure staff are aware of the proper protocols, the report said.
"This occurrence underscores the challenge of managing fatigue on the flight deck," said lead investigator Jon Lee. "It also shows that in-flight passenger injuries can be prevented by wearing seatbelts at all times while seated."