A sleepy pilot who mistook the planet Venus for an oncoming plane sent his Air Canada jet into a steep dive that bounced passengers off the ceiling, injuring 16, and nearly caused a collision with a real plane flying 1,000 feet lower.
Air Canada initially described the injuries to 14 passengers and two flight attendants as the result of "severe turbulence," but a report released this week by the Transportation Safety Board of Canada explains what really happened over the Atlantic Ocean on an overnight flight from Toronto to Zurich on Jan. 14, 2011.
According to the report, the plane's first officer had been sleeping, as is permitted by Air Canada on transatlantic flights, when he was awakened by the pilot's report of the plane's position.
The pilot indicated that a U.S. Air Force cargo plane was approaching the Air Canada 767-300 at an elevation about 1,000 feet below the passenger jet.
The "confused and disoriented" first officer, however, believed that the planet Venus was the approaching plane, and was coming right at the Air Canada jet. He forced the plane into a dive.
Passengers who were not wearing seatbelts, many of them asleep, were slammed into the ceiling and overhead bins.
Realizing what had happened, the pilot was able to pull the plane out of the dive after it had descended 400 feet. The U.S. military plane passed safely underneath.
Seven of the injured were treated in a Swiss hospital after the plane landed safely.
Astronomers say that on that night in January 2011, Venus would have look exceedingly bright from the airplane's cockpit, and a groggy pilot could easily have mistaken the planet for a plane.
"It looks like the headlight on an airplane," said Joseph Rao of the American Museum of Natural History in New York. "It's exceedingly bright. It doesn't twinkle, it's not like a star in that it twinkles. It looks like a steady, white spot of light in the sky. In fact we call it the evening star but they really should call it the evening lantern because it is so much brighter than any of the other stars."
"On that night it would have been ten times brighter than the brightest star," explained Dr. Arlin Crotts of Columbia University.
John Nance, a former commercial pilot and ABC News aviation analyst, said it was "not outlandish" for a pilot to confuse an object as bright as Venus for an oncoming aircraft. "What's surprising is that it went far enough to take evasive action," said Nance.
A passenger on-board the flight captured the aftermath of the incident on video, now posted on YouTube. "We just had the most amazing turbulence," says the passenger, who notes that another passenger's laptop had gone flying. "I hit the roof, everyone is safe, but this is part of the damage," she says, showing damage to the overhead bins.
Tired Skies: Pilot Fatigue
According to the report, the first officer had slept 75 minutes, and was suffering from "sleep inertia" and fatigue. Canadian regulations permit 40-minute naps, and pilots and co-pilots are supposed to be allowed an extra 15 minutes once awake to regain full alertness. U.S. rules do not allow in-cockpit naps.
"This occurrence underscores the challenge of managing fatigue on the flight deck," said lead investigator Jon Lee in a statement.
ABC News explored the connection between pilot sleep, or the lack of it, and air safety, in a series of reports in 2011.
In the U.S., more than two dozen accidents and more than 250 fatalities between 1991 and 2011 have been linked to pilot fatigue, according to the National Transportation Safety Board. The NTSB investigation into the Feb. 12, 2009 crash of Continental 3407, operated by Colgan Air, near Buffalo, N.Y., determined that both pilots were sleep-deprived at the time of the crash.
"Well-rested pilots are very important because studies have shown that being tired is equivalent to being drunk," said Mary Schiavo, former Inspector General of the Transportation Department. "In fact in recent studies, including by Harvard, Stamford, and others have shown that pilots that are sleep deprived behave as someone who has had a few drinks."
"Fatigue has a big impact on your ability to perform," said human fatigue expert Dr. Martin Moore-Ede, CEO of Circadian Technologies. "You might say that fatigue makes you stupid. In other words, all the things you learned in your training, in your hours in the simulator ... those things tend to fall away when you're in a fatigue state."
While the FAA has imposed some new rules to fight pilot fatigue, it did not address the problem of pilots who commute long distance to their bases, often spending the night in crew lounges, or in so-called crash pads near the airport, where quality sleep can be elusive. Both pilots in the Colgan crash were "commuters" who had slept in the airport crew lounge before the fatal flight.