Friday, June 24, 2011

Unplanned Freefall?

Let's say your jet blows apart at 35,000 feet. You exit the aircraft, and you begin to descend independently. Now what?

By David Carkeet
First of all, you're starting off a full mile higher than Everest, so after a few gulps of disappointing air you're going to black out. This is not a bad thing. If you have ever tried to keep your head when all about you are losing theirs, you know what I mean. This brief respite from the ambient fear and chaos will come to an end when you wake up at about 15,000 feet. Here begins the final phase of your descent, which will last about a minute. It is a time of planning and preparation. Look around you. What equipment is available? None? Are you sure? Look carefully. Perhaps a shipment of packed parachutes was in the cargo hold, and the blast opened the box and scattered them. One of these just might be within reach. Grab it, put it on, and hit the silk. You're sitting pretty.
Other items can be helpful as well. Let nature be your guide. See how yon maple seed gently wafts to earth on gossamer wings. Look around for a proportionate personal vehicle—some large, flat, aerodynamically suitable piece of wreckage. Mount it and ride, cowboy! Remember: molecules are your friends. You want a bunch of surface-area molecules hitting a bunch of atmospheric molecules in order to reduce your rate of acceleration.
As you fall, you're going to realize that your previous visualization of this experience has been off the mark. You have seen yourself as a loose, free body, and you've imagined yourself in the belly-down, limbs-out position (good: you remembered the molecules). But, pray tell, who unstrapped your seat belt? You could very well be riding your seat (or it could be riding you; if so, straighten up and fly right!); you might still be connected to an entire row of seats or to a row and some of the attached cabin structure.
If thus connected, you have some questions to address. Is your new conveyance air-worthy? If your entire row is intact and the seats are occupied, is the passenger next to you now going to feel free to break the code of silence your body language enjoined upon him at takeoff? If you choose to go it alone, simply unclasp your seat belt and drift free. Resist the common impulse to use the wreckage fragment as a "jumping-off point" to reduce your plunge-rate, not because you will thereby worsen the chances of those you leave behind (who are they kidding? they're goners!), but just because the effect of your puny jump is so small compared with the alarming Newtonian forces at work.
Just how fast are you going? Imagine standing atop a train going 120 mph, and the train goes through a tunnel but you do not. You hit the wall above the opening at 120 mph. That's how fast you will be going at the end of your fall. Yes, it's discouraging, but proper planning requires that you know the facts. You're used to seeing things fall more slowly. You're used to a jump from a swing or a jungle gym, or a fall from a three-story building on TV action news. Those folks are not going 120 mph. They will not bounce. You will bounce. Your body will be found some distance away from the dent you make in the soil (or crack in the concrete). Make no mistake: you will be motoring.
At this point you will think: trees. It's a reasonable thought. The concept of "breaking the fall" is powerful, as is the hopeful message implicit in the nursery song "Rock-a-bye, Baby," which one must assume from the affect of the average singer tells the story not of a baby's death but of its survival. You will want a tall tree with an excurrent growth pattern—a single, undivided trunk with lateral branches, delicate on top and thicker as you cascade downward. A conifer is best. The redwood is attractive for the way it rises to shorten your fall, but a word of caution here: the redwood's lowest branches grow dangerously high from the ground; having gone 35,000 feet, you don't want the last 50 feet to ruin everything. The perfectly tiered Norfolk Island pine is a natural safety net, so if you're near New Zealand, you're in luck, pilgrim. When crunch time comes, elongate your body and hit the tree limbs at a perfectly flat angle as close to the trunk as possible. Think!
Snow is good—soft, deep, drifted snow. Snow is lovely. Remember that you are the pilot and your body is the aircraft. By tilting forward and putting your hands at your side, you can modify your pitch and make progress not just vertically but horizontally as well. As you go down 15,000 feet, you can also go sideways two-thirds of that distance—that's two miles! Choose your landing zone. You be the boss.
If your search discloses no trees or snow, the parachutist's "five-point landing" is useful to remember even in the absence of a parachute. Meet the ground with your feet together, and fall sideways in such a way that five parts of your body successively absorb the shock, equally and in this order: feet, calf, thigh, buttock, and shoulder. 120 divided by 5 = 24. Not bad! 24 mph is only a bit faster than the speed at which experienced parachutists land. There will be some bruising and breakage but no loss of consciousness to delay your press conference. Just be sure to apportion the 120-mph blow in equal fifths. Concentrate!
Much will depend on your attitude. Don't let negative thinking ruin your descent. If you find yourself dwelling morbidly on your discouraging starting point of seven miles up, think of this: Thirty feet is the cutoff for fatality in a fall. That is, most who fall from thirty feet or higher die. Thirty feet! It's nothing! Pity the poor sod who falls from such a "height." What kind of planning time does he have?
Think of the pluses in your situation. For example, although you fall faster and faster for the first fifteen seconds or so, you soon reach "terminal velocity"—the point at which atmospheric drag resists gravity's acceleration in a perfect standoff. Not only do you stop speeding up, but because the air is thickening as you fall, you actually begin to slow down. With every foot that you drop, you are going slower and slower.
There's more. When parachutists focus on a landing zone, sometimes they become so fascinated with it that they forget to pull the ripcord. Since you probably have no ripcord, "target fixation" poses no danger. Count your blessings.
Think of others who have gone before you. Think of Vesna Vulovic, a flight attendant who in 1972 fell 33,000 feet in the tail of an exploded DC-9 jetliner; she landed in snow and lived. Vesna knew about molecules.
Think of Joe Hermann of the Royal Australian Air Force, blown out of his bomber in 1944 without a parachute. He found himself falling through the night sky amid airplane debris and wildly grabbed a piece of it. It turned out to be not debris at all, but rather a fellow flyer in the process of pulling his ripcord. Joe hung on and, as a courtesy, hit the ground first, breaking the fall of his savior and a mere two ribs of his own. Joe was not a quitter. Don't you be.
Think of Nick Alkemade, an RAF tailgunner who jumped from his flaming turret without a parachute and fell 18,000 feet. When he came to and saw stars overhead, he lit a cigarette. He would later describe the fall as "a pleasant experience." Nick's trick: fir trees, underbrush, and snow.
But in one important regard, Nick is a disappointment. He gave up. As he plummeted to Germany, he concluded he was going to die and felt "a strange peace." This is exactly the wrong kind of thinking. It will get you nowhere but dead fast. You cannot give up and plan aggressively at the same time.

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