The dark of night still draped Mineta San Jose International Airport when a 15-year-old boy from nearby Santa Clara wandered onto a secure airport ramp and toward a Hawaiian Airlines Boeing 767.
Then he disappeared.
The slight teenager, first seen on a security camera video, would not appear again until later Sunday morning, when airline workers spotted him 2,350 miles to the west, walking on the tarmac at Kahului Airport on the island of Maui.
In the interim, authorities say, the boy survived a perilous, 5 1/2 -hour odyssey — enduring frigid temperatures, oxygen deprivation and a compartment unfit for human habitation — as he traveled over the Pacific Ocean in the jet's wheel well.
The incident prompted authorities to question both how the teen so easily gained access to the jumbo jet and how he survived with so little apparent trauma.
Aviation security experts said it was troubling that the teenage had been able to bypass security and get to the plane undetected. U.S. Rep. Eric Swalwell (D-Dublin), a member of the House Homeland Security Committee, said he wanted more answers, adding that the incident "demonstrates vulnerabilities that need to be addressed."
The Transportation Security Administration planned to meet with law enforcement and airport officials to review security after the incident, which experts noted could have been catastrophic had the stowaway been armed with explosives.
Since the terrorist attacks of Sept. 11, 2001, an estimated $57 billion has been spent on airport security improvements, including new passenger screening measures and additional security both in airports and on airplanes.
Brian Jenkins, an aviation security expert at Rand Corp., said he expected the incident to prompt airport security reviews beyond San Jose. "Everyone will tighten up. I suspect everyone will be going up a notch just as a consequence of this," he said.
The airport, which serves Silicon Valley, is located on the north side of San Jose, near the junction of the 101 and 880 freeways. A chain-link fence covered with wood slats and topped with three strands of razor wire surround parts of the airport. San Jose is the 44th largest airport in the nation, according to an Federal Aviation Administration report, with about 8 million passengers a year.
It remains unclear how the teen got onto the tarmac. The FBI originally said video showed him scaling a fence. But late Monday, airport officials only mentioned a video that showed him walking on the ramp.
Authorities said the teenager apparently had no malicious intent. The flight, carrying 212 passengers and 10 crew members, took off at 7:55 a.m. Sunday.
Shortly after the plane landed at 10:31 a.m., airline workers spotted the stowaway and reported him to airport security. A Maui News photo showed him some time later sitting upright on a gurney, attended by paramedics, apparently alert and showing no obvious signs of his ordeal. He wore a sweat shirt with an orange hood.
Authorities said the temperature at the jet's cruising altitude of 38,000 feet could have dropped to 50 degrees below zero or less. Oxygen would have also been in painfully short supply at that altitude, about 9,000 feet higher than the summit of Mt. Everest.
FBI spokesman Tom Simon said the boy apparently had been unconscious for the "lion's share of the flight."
Such ordeals do not usually end well. Those who do not fall to their death can be crushed by landing gear or succumb to cold and lack of oxygen. FAA records show that of the 105 people who stowed away on flights around the world over the last 67 years, 25 lived through the ordeal, a survival rate of 23.8%.
"He must have had the four-leaf clover in his hand or something," said Jeff Price, an aviation security expert at Metropolitan State University in Denver.
Armand Dorian, a Los Angeles doctor who treated a high-altitude stowaway survivor in 2000, said the teen's survival over the weekend was not as surprising as the fact that he appeared unruffled.
For the minority of stowaways who survive, "the planets align," said Dorian, an associate clinical professor of emergency medicine at USC Verdugo Hills Hospital. For the lucky few, "the need for oxygen declines as the body cools. It's exactly like the concept of cryogenic freezing.... The boy's body went into a frozen state."
When Dorian treated another wheel-well stowaway in 2000, the patient suffered much more obvious trauma. That victim, in his 20s, crumpled on to the tarmac at Los Angeles International Airport after a 7 1/2 hour flight from Tahiti. His body core temperature had dropped to 79 degrees, which would normally be fatal, according to accounts at the time.
Dorian recalled that the patient had to be placed on a ventilator and pumped full of warm fluids via tubes inserted in his chest. Because of the teen's unscathed appearance, the doctor is skeptical about where in the plane he actually traveled.
The FBI and Hawaiian Airlines officials said, however, that they were convinced the teen had made the trip in the wheel well, which is not heated or pressurized like the airliner's main cabin.
Experts had no trouble imagining much more severe outcomes for Flight 45. "People go over the fence, they're caught. But he got all the way to the aircraft," said security expert Price. "The question it brings up is: What's to stop somebody from putting a bomb on the plane with the same method?"
Jenkins, with Rand Corp., said it's unclear whether an adequate security system was poorly monitored or whether safeguards needed to be revamped entirely.
"If he was on the camera, why wasn't there a response? Was no one watching the monitors?" Jenkins said. "The first question will be, 'Gee, the cameras work, the response didn't. Was it just missed and they went back and searched through that time frame and oops — there he is?'"
Though the wayward teenager was probably guilty of criminal trespass, the San Jose Police Department had no intention of pursuing criminal charges, according to an FBI official also following up on the case.
Little is known about why the teenager became a stowaway. An FBI official told the Associated Press that he had run away from his family after an argument. But a woman who identified herself as the teen's older sister told an NBC affiliate that that was not the case. The various agencies investigating said it was not even clear that the teenager knew where the jet was headed.
Airport personnel in Hawaii said they had turned the boy over to Hawaii's child protection office, which said it was preparing to return the boy home. Dorian said the unknown traveler's immediate good fortune does not mean he is home free.
He estimated that the boy's heart rate could have dropped to as low as 10 or 12 beats a minute. He said doctors would have to keep an eye out for longer-term symptoms like headaches and depression that might not emerge for months.
But the doctor added that the teen was walking and talking, which is the best sign that his prognosis is hopeful.