It's a traveler's worst nightmare: missing a connecting flight. But few can say it's because they slept through the plane's landing.
Although some people can sleep through just about anything, experts say it's highly unusual that the noise and commotion of disembarking would fail to wake a passenger.
“[This] is somewhat atypical,” says Dr. Alon Avidan, a professor of neurology and director of the UCLA Sleep Disorders Center.
"I just don't know how it happened, I really don't," said Tom Wagner, a Louisiana boat captain on his way to Los Angeles who woke from a nap during his connecting flight to Houston to find himself locked in an empty plane. He was finally freed when when United Airlines maintenance workers came to check the plane. "I mean, passengers got off. You think somebody would have rubbed me or pushed me and say 'Hey, we're here.'"
The droning of the plane and the motion might have initially lulled him to sleep. But, sleep disorder specialists know there is more to his deep sleep than this.
“He is probably sleep deprived,” says Dr. Charles Bae, a sleep specialist at Cleveland Clinic.
Avidan and Bae suspect that Wagner was in stage four sleep, also known as slow-wave sleep. In this stage of sleep, the body recovers from sleep deprivation and people are unaware of any auditory or environmental cues. People generally spend about 20 percent of their sleep in this state, closer to the beginning of the night’s rest.
“He was completely unaware,” Avidan says. “We don’t really dream [in stage four].”
People in this stage of sleep are very calm and relaxed and not easily awoken. Children are especially sound sleepers in this state — even the loudest of noises won’t cause them to stir. The experts agree that it would take a good shake to wake someone in slow-wave sleep. And, if the flight attendants managed to wake him, he’d probably be pretty confused.
“He may have been groggy and [had] that drunken feeling,” says Bae.
The fact that Wagner was so deeply asleep might indicate that he has an underlying sleep disorder — or he needs to get a good night’s rest. The two recommend that he try to improve his sleep and see a doctor to rule out any sleep disorders.
“It is a little unusual for his age to be so unengaged and unaware,” Avidan says.