In a video posted by CNN on Sunday, passenger Eugene Rah credits his survival to something most coach passengers don’t have much familiarity with: a three-point seat belt.
They've been in cars since the 1960s. But they’re still a rare sight on airliners unless you’re in business-or-first class, like Eugene Rah was on Asiana Flight 214.
“Luckily the seat I was sitting [in] it has one more strap coming across my chest, in addition to the one going around the waist, because it was a sleeper seat,” Rah told CNN. “If I did not have that, I’d have hit the ceiling. That’s how hard the impact was.”
What’s this? First-class passengers get better, safer seat-belts than coach passengers?
According to Robert Salzar, a scientist at the Center for Applied Biomechanics at the University of Virginia, it’s a little more complicated than that.
Salzar says in order to pass FAA regulations, airplane seats undergo crash tests, just as cars do.
“If you’re a seat manufacturer, you design a seat and you have to get the seat certified by the FAA. And that involves placing a 50-percentile male crash test dummy in the seat and subjecting it to a frontal collision of a certain intensity.”
Manufacturers have to show that something restrains the dummy from hitting his head on his knees, or something else in his vicinity. In coach, that's what the seat in front of you does.
In a big impact, says Salzar, “your body pivots forward at the hip, and your face or your head is going impact the seat in front of you. And that seat is actually going to support your head and your neck.”
Even with a built-in screen or a phone, says Salzar, the surface of that seat-back is still pretty soft. It can save your life (or your back).
But up in first class, there’s a lot more space: room to stretch your legs, open a newspaper--and get seriously hurt in the event of a sudden jolt.
“Nothing’s gonna support your head,” Salzar says. That’s why some airlines have added three-point harness systems, like those in your car, to first-class and bulkhead seats, he explained. “That makes up for the impact you’d normally get from the seat in front of you.”
Back in coach, that lap belt should keep you from flying out of your seat. But you’ve got to wear it the right way, which is why flight crews are always reminding us: “low and tight across your lap.”
“If your seat belt is high and riding on soft tissue of your abdomen and not across your pelvic girdle,” says Salzar, “you run the risk of abdominal injury.”
Abdominal injuries are among those suffered by survivors of the Asiana crash. So are spinal cord injuries and fractures.
Salzar says it’s way too early to speculate what could have caused the injuries passengers sustained in the Asiana crash. But it’s possible that the type of impact was beyond what most airplane seats are designed to handle.
“If you look at the video," Salzar points out, the plane "managed to do a 360-degree spin."
He says inside the cabin, it would have felt like a “bad roller coaster ride.”
“You're going to have your neck wrenched around pretty bad. So you could have some lateral rolling, some torque on your spine. It's going to be a fairly violent event. And that's not what these seats are designed to protect against.”
The Asiana 777 was delivered in 2006. Newer planes, built after 2009, must have seats that can withstand greater impact.
To meet that standard, some manufacturers have added airbags to lap belts. And some are looking into what it would take to install three-point belt systems in coach seats, too.
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