A teenage boy who sneaked into the wheel well of a flight to Hawaii from San Jose airport was called "lucky to be alive" by the FBI after he survived the five-hour journey.

The 16-year-old was discovered by airport personnel at the Maui airport's tarmac without identification. FBI spokesman Tom Simon told NBC News that the boy is "a runaway from Santa Clara, Calif., who stowed away aboard Hawaiian Airlines Flight 45 on Sunday morning after apparently choosing the plane at random."

Apparently he had an argument with his family, and Simon said, "He was unconscious for the lion's share of the flight... Doesn't even remember the flight. It's amazing he survived that."

The teen appears to be medically fine. The airlines said that its staff "noticed the individual on the ramp after the flight's arrival and immediately notified airport security... Our primary concern now is for the wellbeing of the boy, who is exceptionally lucky to have survived."

According to HawaiiNewsNow, "Trans Pacific flights usually fly at altitudes of about 38,000 feet, making it extremely difficult to breathe. Temperatures also drop to as low as 80 degrees below zero." An aviation expert, Peter Forman, said, "Within a few minutes up at that altitude, the person would pass out and usually they would not survive for hours on end up there so it just boggles the mind. You would suffocate most likely up there. It's extremely unlikely that somebody would survive that long at that altitude. And if they did survive, you would think that they would have frostbite and all sorts of problems associated with the cold up there."

The Mineta San Jose Airport hasn't commented about the incident. The boy is in custody of child protective services.