by Mary Roach
When I tell him I was disappointed over not being able to report from the scene of a crash, Shanahan hands me a book called Aerospace Pathology, which, he assures me, contains photographs of the sorts of things I might have seen. I open the volume to a section on “body plotting.” Among line sketches of downed plane pieces, small black dots are scattered. Leader lines spoke away from the dots to their labels: “brown leather shoes,” “copilot,” “piece of spine,” “stewardess.” By the time I get to the chapter that describes Shanahan’s work—“Patterns of Injury in Fatal Aircraft Accidents,” wherein photo captions remind investigators to keep in mind things like “intense heat may produce intracranial steam resulting in blowout of the cranial vault, simulating injuries from impact”—it has become clear to me that labeled black dots are as up-close-and-personal as I wish to get to the human wreckage of a plane crash.
In the case of TWA Flight 800, Shanahan was on the trail of a bomb. He was analyzing the victims’ injuries for evidence of an explosion in the cabin. If he found it, he would then try to pinpoint where on the plane the bomb had been. He takes a thick folder from a file cabinet drawer and pulls out his team’s report. Here is the chaos and gore of a major passenger airline crash quantified and outlined, with figures and charts and bar graphs, transformed from horror into something that can be discussed over coffee in a National Transportation Safety Board morning meeting. “4.19: Injury Predominance Right vs. Left with Floating Victims.” “4.28: Mid-Shaft Femur Fractures and Forward Horizontal Seat Frame Damage.” I ask Shanahan whether the statistics and the dispassionate prose helped him maintain what I imagine to be a necessary emotional remove from the human tragedy behind the inquiry. He looks down at his hands, which rest, fingers interlinked, on the Flight 800 folder.
“Maureen will tell you I coped variably with Flight 800. It was emotionally very traumatic, particularly with the number of teenagers on board. A high school French club going to Paris. Young couples. We were all pretty grim.” Shanahan says this isn’t typical of the mood behind the scenes at a crash site. “You want a very superficial involvement, so jokes and lightheartedness tend to be fairly common. Not this time.”
For Shanahan, the hardest thing about Flight 800 was that most of the bodies were relatively whole. “Intactness bothers me much more than the lack of it,” he says. The sorts of things most of us can’t imagine seeing or coping with—severed hands, legs, scraps of flesh—Shanahan is more comfortable with. “That way, it’s just tissue. You can put yourself in that frame of mind and get on with your job.” It’s gory, but not sad. Gore you get used to. Shattered lives you don’t. Shanahan does what the pathologists do. “They focus on the parts, not the person. During the autopsy, they’ll be describing the eyes, then the mouth. You don’t stand back and say, ‘This is a person who is the father of four.’ It’s the only way you can emotionally survive.”
Ironically, intactness is one of the most useful clues in determining whether a bomb has gone off. We are on page 16 of the report, Heading 4.7: Body Fragmentation. “People very close to an explosion come apart,” Shanahan says to me quietly. Dennis has a way of talking about these things that seems neither patronizingly euphemistic nor offensively graphic. Had there been a bomb in the cabin of Flight 800, Shanahan would have found a cluster of “highly fragmented bodies” corresponding to the seats nearest the explosion. In fact, most of the bodies were primarily intact, a fact quickly gleaned by noting their body fragmentation code. To simplify the work of people like Shanahan who must analyze large numbers of reports, medical examiners often use color codes. On Flight 800, for instance, people ended up either Green (body intact), Yellow (crushed head or the loss of one extremity), Blue (loss of 2 extremities with or without crushed head), or Red (loss of 3 or more extremities or complete transection of body).
Another way the dead can help determine whether a bomb went off is through the numbers and trajectories of the “foreign bodies” embedded within them. These show up on X-rays, which are routinely taken as part of each crash autopsy. Bombs launch shards of themselves and of nearby objects into people seated close by; the patterns within each body and among the bodies overall can shed light on whether a bomb went off and where. If a bomb went off in a starboard bathroom, for instance, the people whose seats faced it would carry fragments that entered the fronts of their bodies. People across the aisle from it would display these injuries on their right sides. As Shanahan had expected, no telltale patterns emerged.
Shanahan turned next to the chemical burns found on some of the bodies. These burns had begun to fuel speculation that a missile had torn through the cabin. It’s true that chemical burns in a crash are usually caused by contact with highly caustic fuel, but Shanahan suspected that the burns had happened after the plane hit the water. Spilled jet fuel on the surface of the water will burn a floating body on its back, but not on its front. Shanahan checked to be sure that all the “floaters”—people recovered from the water’s surface—were the ones with the chemical burns, and that these burns were on their backs. And they were. Had a missile blasted through the cabin, the fuel burns would have been on people’s fronts or sides, depending on where they had been seated, but not their backs, as the seatbacks would have protected them. No evidence of a missile.
Shanahan also looked at thermal burns, the kind caused by fire. Here there was a pattern. By looking at the orientation of the burns—most were on the front of the body—he was able to trace the path of a fire that had swept through the cabin. Next he looked at data on how badly these passengers’ seats had been burned. That their chairs were far more severely burned than they themselves were told him that people had been thrown from their seats and clear of the plane within seconds after the fire broke out. Authorities had begun to suspect that a wing fuel tank had exploded. The blast was far enough away from passengers that they had remained intact, but serious enough to damage the body of the plane to the point that it broke apart and the passengers were thrown clear.
I ask Shanahan why the bodies would be thrown from the plane if they were wearing seat belts. Once a plane starts breaking up, he replies, enormous forces come into play. Unlike the split-second forces of a bomb, they won’t typically rip a body apart, but they are powerful enough to wrench passengers from their seats. “This is a plane that’s traveling at three hundred miles per hour,” Shanahan says. “When it breaks up, it loses its aerodynamic capability. The engines are still providing thrust, but now the plane’s not stable. It’s going to be going through horrible gyrations. Fractures propagate and within five or six seconds this plane’s in chunks. My theory is that the plane was breaking up pretty rapidly, and seatbacks were collapsing and people were slipping out of their restraint systems.”
The Flight 800 injuries fit Dennis’s theory: People tended to have the sort of massive internal trauma that one typically sees from what they call in Shanahan’s world “extreme water impact.” A falling human stops short when it hits the surface of the water, but its organs keep traveling for a fraction of a second longer, until they hit the wall of the body cavity, which by that point has started to rebound. The aorta often ruptures because part of it is fixed to the body cavity—and thus stops at the same time—while the other part, the part closest to the heart, hangs free and stops slightly later; the two parts wind up traveling in opposite directions and the resultant shear forces cause the vessel to snap. Seventy-three percent of Flight 800’s passengers had serious aortic tears.
The other thing that reliably happens when a body hits water after a long fall is that the ribs break. This fact has been documented by former Civil Aeromedical Institute researchers Richard Snyder and Clyde Snow. In 1968, Snyder looked at autopsy reports from 169 people who had jumped off the Golden Gate Bridge. Eighty-five percent had broken ribs, whereas only 15 percent emerged with fractured vertebrae and only a third with arm or leg fractures. Broken ribs are minor in and of themselves, but during high-velocity impacts they become sharp, jagged weapons that pie
rce and slice what lies within them: heart, lungs, aorta. In 76 percent of the cases Snyder and Snow looked at, the ribs had punctured the lungs. Statistics from Flight 800 sketched a similar scenario: Most of the bodies displayed the telltale internal injuries of extreme water impact. All had blunt chest injuries, 99 percent had multiple broken ribs, 88 percent had lacerated lungs, and 73 percent had injured aortas.
If a brutal impact against the water’s surface was what killed most passengers, does that mean they were alive and aware of their circumstances during the three-minute drop to the sea? Alive, perhaps. “If you define alive as heart pumping and them breathing,” says Shanahan. “there might have been a significant number.” Aware? Dennis doesn’t think so. “I think it’s very remote. The seats and the passengers are being tossed around. You’d just get overwhelmed.” Shanahan has made a point of asking the hundreds of plane and car crash survivors he interviews what they felt and observed during their accident. “I’ve come to the general conclusion that they don’t have a whole lot of awareness that they’ve been severely traumatized. I find them very detached. They’re aware of a lot of things going on, but they give you this kind of ethereal response—‘I knew what was going on, but I didn’t really know what was going on. I didn’t particularly feel like I was a part of it, but on the other hand I knew I was a part of it.’”
Given that so many Flight 800 passengers were thrown clear of the plane as it broke apart, I wondered whether they stood a chance—however slim—of surviving. If you hit the water like an Olympic diver, might it be possible to survive a fall from a high-flying plane? It has happened at least once. In 1963, our man of the long-distance plummet, Richard Snyder, turned his attention to people who had survived falls from normally fatal heights. In “Human Survivability of Extreme Impacts in Free-Fall,” he reports the case of a man who fell seven miles from an airplane and survived, albeit for only half a day. And this poor sap didn’t have the relative luxury of a water landing. He hit ground. (From that height, in fact, there is little difference.) What Snyder found is that a person’s speed at impact doesn’t dependably predict the severity of his or her injuries. He spoke with eloping bridegrooms who sustained more debilitating injuries falling off their ladders than did a suicidal thirty-six-year-old who dropped seventy-one feet onto concrete. The latter walked away needing nothing more than Band-Aids and a therapist.
Generally speaking, people falling from planes have booked their final flight. According to Snyder’s paper, the maximum speed at which a human being has a respectable shot at surviving a feet-first—that’s the safest position—fall into water is about 70 mph. Given that the terminal velocity of a falling body is 120 mph, and that it takes only five hundred feet to reach that speed, you are probably not going to fall five miles from an exploding plane and live to be interviewed by Dennis Shanahan.
Was Shanahan right about Flight 800? He was. Over time, critical pieces of the plane were recovered, and the wreckage supported his findings. The final determination: Sparks from frayed wiring had ignited fuel vapors, causing an explosion of one of the fuel tanks.
The unjolly science of injury analysis got its start in 1954, the year two British Comet airliners mysteriously dropped from the sky into the sea. The first plane vanished in January, over Elba, the second off Naples three months later. In both crashes, owing to the depth of the water, authorities were unable to recover much of the wreckage and so turned for clues to the “medical evidence”: the injuries of the twenty-one passengers recovered from the surface of the sea.
The investigation was carried out at Britain’s Royal Air Force Institute of Aviation Medicine in Farnborough, by the organization’s group captain, W. K. Stewart, in conjunction with one Sir Harold E. Whittingham, director of medical services for the British Overseas Airways Corporation. As Sir Harold held the most degrees—five are listed on the published paper, not counting the knighthood—I will, out of respect, assume him to have been the team leader.
Sir Harold and his team were immediately struck by the uniformity of the corpses’ injuries. All twenty-one cadavers showed relatively few external wounds and quite severe internal injuries, particularly to the lungs. Three conditions were known to cause lung injuries such as those found in the Comet bodies: bomb blast, sudden decompression—as happens when pressurization of an airplane cabin fails—and a fall from extreme heights. Any one of them, in a crash like these, was a possibility. So far, the dead weren’t doing much to clear up the mystery.
The bomb possibility was the first to be ruled out. None of the bodies were burned, none had been penetrated with bomb-generated shrapnel, and none had been, as Dennis Shanahan would put it, highly fragmented. The insane, grudge-bearing, explosives-savvy former Comet employee theory quickly bit the dust.
Next the team considered sudden depressurization of the passenger cabin. Could this possibly cause such severe lung damage? To find out, the Farnborough team recruited a group of guinea pigs and exposed them to a sudden simulated pressure drop—from sea level to 35,000 feet. To quote Sir Harold. “The guinea pigs appeared mildly startled by the experience but showed no signs of respiratory distress.” Data from other facilities, based on both animal experimentation and human experiences, showed similarly few deleterious effects—certainly not the kind of damage seen in the lungs of the Comet passengers.
This left our friend “extreme water impact” as the likely cause of death, and a high-altitude cabin breakup, presumably from some structural flaw, as the likely cause of the crash. As Richard Snyder wouldn’t write “Fatal Injuries Resulting from Extreme Water Impact” for another fourteen years, the Farnborough team turned once again to guinea pigs. Sir Harold wanted to find out exactly what happens to lungs that hit water at terminal velocity. When I first saw mention of the animals, I pictured Sir Harold trekking to the cliffs of Dover, rodent cages in tow, and hurling the unsuspecting creatures into the seas below, where his companions awaited in rowboats with nets. But Sir Harold had more sense than I; he and his men devised a “vertical catapult” to achieve the necessary forces in a far shorter distance. “The guinea pigs,” he wrote, “were lightly secured by strips of adhesive paper to the under surface of the carrier so that, when the latter was arrested to the lower limit of its excursion, the guinea pig was projected belly first, about 2½ feet through the air before hitting the water.” I know just the sort of little boy Sir Harold was.
To make a long story short, the catapulted guinea pigs’ lungs looked a lot like the Comet passengers’ lungs. The researchers concluded that the planes had broken apart at altitude, spilling most of their human contents into the sea. To figure out exactly where the fuselage had broken apart, they looked at whether the passengers had been clothed or naked when pulled from the sea. Sir Harold’s theory was that hitting the sea from a height of several miles would knock one’s clothes off, but that hitting the sea inside the largely intact tail of the plane would not, and that they could therefore surmise the point of breakup as the dividing line between clothed and naked cadavers. For in both flights, it was the passengers determined (by checking the seating chart) to have been in the back of the plane who wound up floating in their clothes, while passengers seated forward of a certain point were found floating naked, or practically so.
To prove his theory, Sir Harold lacked one key piece of data: Was it indeed true that hitting the sea after falling from an airplane would serve to knock one’s clothes off? Ever the pioneer, Sir Harold undertook the study himself. Though I would like nothing better than to be able to relate to you the details of another Farnborough guinea pig study, this one featuring the little rodents outfitted in tiny worsted suits and 1950s dresses, in point of fact no guinea pigs were used. The Royal Aircraft Establishment was enlisted to pilot a group of fully clothed dummies to cruising altitude and drop them into the sea.* As Sir Harold had expected, their clothes were indeed blown off on impact, a phenomenon verified by Marin County coroner Gary Erickson, the man who autopsies the bodies of Golden Ga
te Bridge suicides: Even after falling just 250 feet, he told me. “typically the shoes get blown off, the crotch gets blown out of the pants, one or both of the rear pockets are gone.”
In the end, enough of the Comet wreckage was recovered to verify Sir Harold’s theories. A structural failure had indeed caused both planes to break apart in midair. Hats off to Sir Harold and the guinea pigs of Farnborough.
Dennis and I are eating an early lunch at an Italian restaurant near the beach. We are the only customers, and it’s way too quiet for the conversation going on at our table. Whenever the waiter appears to refill our water glasses, I pause, as though we were discussing something top secret or desperately personal. Shanahan seems not to care. The waiter will be grinding pepper on my salad for what seems like a week, and Dennis is going. “…used a scallop trawler to recover some of the smaller remains…”
I ask Dennis how, knowing what he knows and seeing what he sees, he ever manages to board a plane. He points out that most crashing airplanes don’t hit the ground from thirty thousand feet. The vast majority crash on takeoff or landing, either on or near the ground. Shanahan says 80 to 85 percent of plane crashes are potentially survivable.
The key word here is “potentially.” Meaning that if everything goes the way it went in the FAA-required cabin evacuation simulation, you’ll survive. Federal regulations require airplane manufacturers to be able to evacuate all passengers through half of a plane’s emergency exits within ninety seconds. Alas, in reality, evacuations rarely happen the way they do in simulations. “If you look at survivable crashes, it’s rare that even half the emergency exits open,” says Shanahan. “Plus, there’s a lot of panic and confusion.” Shanahan cites the example of a Delta crash in Dallas. “It should have been very survivable. There were very few traumatic injuries. But a lot of people were killed by the fire. They found them stacked up at the emergency exits. Couldn’t get them open.” Fire is the number one killer in airplane mishaps. It doesn’t take much of an impact to explode a fuel tank and set a plane on fire. Passengers die from inhaling searing-hot air and from toxic fumes released by burning upholstery or insulation. They die because their legs are broken from slamming into the seat in front of them and they can’t crawl to the exits. They die because passengers don’t exit flaming planes in an orderly manner; they stampede and elbow and trample.*