SANTA CLARA (CBS SF) – A Santa Clara teenager remained in custody Tuesday, two days after apparently surviving a five-hour flight across the Pacific Ocean tucked inside the plane’s wheel well.

Maui Police say the boy, who remains unidentified, is originally from Africa and may have been trying to go back to see relatives when he hopped aboard a flight at Mineta San Jose International Airport.

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Medical experts say it’s improbable but not impossible to survive the conditions.

Warm hydraulic lines and warm tires after takeoff may have provided some initial heat, but as the plane climes, the oxygen declines.

“Possibly what happened was he went into a coma,” said Melanie Singh, whoworks in San Francisco General’s Emergency room. “You essentially develop a state called hibernation. What could have potentially happened is the slow down of metabolism, brain and body…for essentials.. to keep him alive.”

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After he stepped out of the wheel well and onto the tarmac in Maui, airport and security personnel escorted him away to be interviewed by local police and the FBI.

The teen reported that he had run away from home. The FBI says his story was investigated and checked out and there was no indication it was a hoax.

Previous studies suggest fewer than 25 percent of people who attempt wheel well stowaways survive such a flight, even at shorter distances.

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