The hole that ripped through the ceiling of a commercial airplane at cruising altitude last week may, for some, have brought to mind the pilot of the TV show "Lost." In that dramatic episode, an airplane breaks in half, and passengers go flying through a gaping hole in the fuselage.
For passengers on Southwest flight 812, the consequences were far milder: Soon after its takeoff from Phoenix, the plane made an emergency landing, and everyone was fine.
But people have been hurled through holes in cruising airplanes before. And that raises an important, if gruesome question: What would happen to you if you were sucked into the atmosphere at 30,000 feet?
The prognosis, experts say, would not be good.
"There are a number of critical physiological problems that would be life-ending, likely within seconds," said Peter Wagner, a physician and physiologist at the University of California, San Diego. "Forget about the fact that you don’t have a parachute. You would be instantly exposed to very, very low oxygen levels. Within three or four seconds, my guess is that you would be breathing like hell."
Loss of consciousness and death would soon follow purely from oxygen deprivation to the brain, Wagner continued. At the same time, temperatures of -70 degrees Fahrenheit (-57 degrees Celsius) -- made even colder by the chill of 500 mile-per-hour (805 kilometer-per-hour) winds -- would lead to rapid freezing, beginning with the skin, eyes and other surface tissues.
In response to such extreme stress, your nervous system would go haywire, leading to potentially fatal spikes in blood pressure and heart rate. And the sudden change in air pressure would lead to a nasty case of the bends, as if you were scuba diving and came up too fast.
Then, there’s the danger of getting slammed into the plane on the way out, not to mention the trauma of falling.
"You would probably be cut in half or something, depending on what you hit and what part of the body connected," Wagner said. "All kinds of awful imagery are possible."
Fortunately, incidents like these are extremely rare. Holes most often appear in military aircraft that have been struck by bullets or explosives, though there have been civilian examples. In 1988, for example, Aloha Airlines flight 243 lost a large section if its roof at 24,000 feet. One flight attendant was blown out of the plane and died.
In events like these, the sucking force originates from a difference in pressure between the cabin environment and the outdoor one. Aircraft are generally kept at an air pressure similar to what you’d find between 6,000 and 8,000 feet above sea level. At a cruising altitude of 30,000 feet, pressure outside of the plane is about two and a half times lower than what passengers experience on the inside.
When a hole forms, a strong tendency to equalize creates a rushing tunnel of wind, like water flowing through a hose. In sections of the plane that are far from the hole, winds might be mild enough to simply whisk papers around.
But air picks up speed as it approaches a fissure, said Geoffrey Landis, a physicist at NASA’s Glenn Research Center in Cleveland. At the point where air passes out of the fuselage, it moves at the speed of sound.
The size of a hole determines how much air could rush out of a plane at once -- and how dangerous the situation will become. According to Landis’ calculations, it would take about 100 seconds for pressure to equalize through a one square-foot hole in the body of a 747. People sitting next to a hole this size would face a half a ton of force barreling against them in the direction of the hole.
Of course, wind forces immediately begin working to enlarge a hole of any size -- putting extra pressure on the pilot to steer the plane downward as fast as possible.
If you are unlucky enough to end up on a plane that develops a hole on it, "all is not doomed," Landis said. In many cases, skilled pilots can react quickly enough to land the plane safely, as in the recent Southwest incident.
There are also some things you can do to protect yourself. Keep your seatbelt fastened. Put on your oxygen mask. And, Wagner suggested, if the hole is caused by something small like a bullet, slap a book or airline magazine over it.
Air pressure will cement the object over the hole. And you will walk away a hero.