Almost No One Died On Asiana 214 Thanks To Incredible Airplane Design

Commercial air travel in the 21st century is not only less deadly than other common forms of travel, it's also safer than it has ever been before.

Part of that can be attributed to technological advances that make accidents more avoidable in the first place, like more reliable engines. But it's also that passengers on planes that do run into trouble now have an excellent chance of surviving.

More than 95% of passengers involved in accidents on U.S. carriers between 1983 and 2000 survived, according to the NTSB.

In the crash landing of Asiana Flight 214, 305 of 307 people survived.

How is that possible? Survivors can thank regulators, airlines, and plane manufacturers for making big steps in three areas.

Surviving Impact

Asiana Flight 214 was traveling at 122 mph when its main landing gear and tail hit the seawall separating the runway from the San Francisco Bay. The tail snapped off, the rest of the 777 yawed left (spun around its center of gravity), and spun 360 degrees as it skidded in the grass alongside the runway.

Since 1988, seats in new planes have been required to be able to withstand 16g forces (16 times the force of gravity) without breaking or coming loose from the floor. According to The New York Times, the figure was chosen because a more severe deceleration is not survivable.

Photos from the aftermath of Flight 214 show that all of the seats were where they should have been, though there are reports of bags and bulkheads coming loose and injuring or trapping passengers.

Then there's the fact the the fuselage itself remained intact, despite the loss of the tail. Kevin Hiatt, CEO of the independent Flight Safety Foundation, called the structural integrity of the fuselage a "continuously improved development."

Over time, officials and manufacturers have identified and strengthened the weaker parts of the fuselage. The floors have been made stronger too, so they don't buckle in the event of a crash.

Holding Back Fire

A 2011 article in Boeing's Aero magazine calls fire protection "one of the high considerations" in airplane design. Both the insulation and the skin that covers the outside of the aircraft are made to resist burn-through for at least four minutes.

The crash landing of the Boeing 777 knocked the right engine toward the fuselage, and a leaking oil tank soon led to a fire. Nearly all the passengers reached safety before the fire entered the cabin, and even by the time emergency responders entered the plane to help those too injured to move, the fire was not yet severe.

That delay, Hiatt said in an interview, can "absolutely" be attributed to the mandatory use of fire resistant materials inside the cabin. They "prevented a flash fire," providing extra time for evacuation.

The situation was helped by the fact that the 777 had just completed a 10-hour flight from Seoul, so its fuel tanks were far from full.

Getting Off The Plane

Per FAA requirements, it must be possible to get all of the passengers off a plane within 90 seconds. This is tested with a diverse range of test passengers who are not familiar with the aircraft, NTSB Chairman Debbie Hersman said in a Tuesday afternoon press conference. During the test, half the exits are blocked, only emergency lighting is used, and the aisles are littered with pillows, blankets, and luggage.

On Flight 214, despite a delay before the evacuation began, and the fact that two of the escape slides deployed inside the plane (each one pinning a flight attendant), the vast majority of those onboard got off remarkably quickly (as this video shows).

Hiatt gave credit to federal requirements that doors be easily operated by passengers as well as crew members, and to the training of the flight attendants. The reduced crew — two were pinned by the slides, and two were ejected from the plane when the tail broke off —directed passengers to the least crowded exits and fought the fire once it entered the cabin, according to Hersman.

"They sprang into action and did what they were trained to do," Hiatt said, noting that they did especially well considering they had no warning a crash was coming.

Beyond The 777

None of these safety measures — the 16g seats, fire resistant materials, or the well-trained crews — are unique to the plane that crashed in San Francisco.

The Boeing 777 is "a very well designed aircraft" that "did extremely well" in this crash, Hiatt said, but its performance was not exceptional. The 26 accidents covered by the NTSB report in which 95.1% of passengers survived involved some 20 different aircraft.

So if you find yourself in trouble in the air, just know there's a good chance you'll live to tell the tale. Just be sure to buckle your seatbelt.

FAA Fact Sheet: Aircraft Survivability