This NTSB handout photo shows the interior of the Asiana Airlines jet that crash landed at San Francisco International Airport on Saturday. Federal regulations developed and adopted over the past couple decades have led to sturdier, safer airline seats. Some safety experts suggest shoulder harnesses should be added to passenger jets, but costs -- and passenger comfort -- are major concerns.
Lap-only seat belts started disappearing from cars decades ago — after all, they're a nearly 100-year-old technology. Yet we still click them in modern airline seats.
There is early indication that some of the injuries suffered during the crash landing of Asiana Airlines Flight 214 resulted from passengers being thrashed about while restrained only in their midsections. Could better seat restraints have prevented more injuries?
"It is indeed possible that different kinds of seat belts — including belts with integrated airbags, or lap and shoulder belt combinations — may have prevented some passenger injuries," said Todd Curtis, aviation safety expert and founder of AirSafe.com. “This is something that the (National Transportation Safety Board) will fully investigate."
Airline lap belts might seem like they belong in a 1973 Dodge Dart, but they have persisted as the main tool to keep passengers safely in their seats during turbulence and crash landings. For decades, efforts to modernize safety equipment on passenger jets with features like shoulder harnesses or airbags have run into engineering, financial and behavioral challenges. Still, flight safety advocates say the airlines should consider some safety upgrades.
Shoulder belts are required for all seats in small, general aviation aircraft, and the FAA says they reduce major injuries in small planes by 88 percent.
“It should be noted that crew members wear harnesses, both in the cockpit and the flight attendants ...There’s no question that they are more effective and can prevent some of the injuries that G-forces cause by putting so much pressure on that one point, at the lap," said Bill McGee, author of "Attention All Passengers: The Airlines’ Dangerous Descent." “Clearly there is a great need for discussing these issues.”
Building a better seat
The FAA has been discussing how to build a better airline seat since at least 1987, when Congress passed the Airport and Airway Safety and Capacity Expansion Act, which included seat safety provisions. More than 20 years in the making, regulatory discussions led to the adoption of the "16g rule" in 2009, which requires airline seats to be able to withstand impacts and protect passengers during crashes that produce forces of up to 16 times the force of gravity.
A smattering of airlines — generally international carriers — installed seat-belt airbags on existing seats in response to the rules, while most installed sturdier seats. (U.S. passengers will find airbags or harness-style belts installed in a few seats on a domestic carrier where other 16g upgrades were impossible, such as some first-class seats.)
Today’s airplane lap belts are designed to restrain 6,000 pounds of force, said an airline seat engineer interviewed by NBC News who asked not to be identified. He said harness belts might be safer, but they are far more challenging to install on an airplane than in a car.
“You need something to attach the shoulder strap to. In a car, you can secure it to the frame. In an aircraft, it is difficult to supply an attachment for an over-the-shoulder belt. It could be done with a reinforced seat, but that would be larger and heavier," he said.
Harnesses are hardly fool-proof, and there's no evidence yet that they would have prevented any of the more serious injuries on Flight 214. One of the flight attendants, presumably wearing a four-point harness as the Boeing 777 was approaching San Francisco International for landing, suffered a broken tailbone.
Still, some general aviation pilots swear by them. Kingsley Hill, a 54-year-old private pilot from New Jersey, crash-landed in Kentucky and told NBC that his safety harness saved him.
“That night when I took my shirt off, there was a large, red welt across chest [sic] from the shoulder harness. I had not even realized how hard I had hit that harness, but our injuries would have been much worse if I hadn't had the welt,” he recalled, describing the incident to other pilots on an aviation website . “Needless to say I am a big fan of shoulder belts.”
It comes down to dollars
Airbags are easier to install because they can be deployed as traditional lap belts. But they raise separate issues. Airbags would be less useful in many airplane crashes, which often involve several consecutive impacts. Airbags inflate once and quickly deflate. They also require regular maintenance and have a much shorter lifespan than airplanes, creating an upkeep headache.
Still, they are catching on with airlines like Cathay Pacific and Air France. AmSafe, one of the largest sellers of airline seat belts and airbags, did not respond to a request for comment. (AmSafe was acquired last year by Cleveland-based TransDigmGroup.)
The biggest obstacle to improved passenger seat safety is likely cost, said former crash inspector Michael Barr, who now is now a senior instructor at University of Southern California’s Aviation Safety and Security program.
"New seat belts are probably a good idea, but it would be very expensive to equip every seat in every plane with a cross-chest belt," Barr said. “It would be cost prohibitive.”
The FAA actually uses a formula that weighs potential lives saved by a safety enhancement with the cost it would impose on the airlines.
When it ran those numbers for the 16g rule, it found that 45 fatalities would have been prevented between 1984 and 1998 had the seats been required during that time.
Instead of an industry-wide retrofit that would have cost half a billion dollars, the airlines were allowed to phase out the old seats and outfit new planes with up-to-date seats.
It's unknown if the FAA has performed a similar calculation with improved seat restraints.
Extra weight, extra fuel
McGee says it's not the cost of better seat belts that concerns the industry, but rather the cost of added fuel. Extra weight from the devices that would secure the shoulder straps would cost airlines millions in fuel every year.
"It’s very difficult to convince the airline industry to do anything that's going to raise costs, particularly fuel costs," McGee said.
The airline industry hasn’t commented on the role better seat restraints may have played in the San Francisco crash. Boeing and Airbus declined to comment for this story; the FAA and the NTSB didn’t respond either.
The International Air Transport Association, the airline’s trade group, said that it adheres to FAA standards.
“The certification standards are what they are. Our members follow the certification standards,” said Perry Flint, IATA’s Assistant Director, Corporate Communications.
If seat belt enhancements are to come, the crash of Flight 214 could be a catalyst, said AirSafe’s Curtis.
“(The NTSB) will document the condition of each passenger seat, likely with the intent of studying how well they dealt with the forces of this particular crash. If the NTSB finds room for improvement, they may publish one or more recommendations for seat requirements, or requirements for more or different seat restraints," he said.
But there might be an even more practical reason that shoulder harnesses will never make it into airline cabins, Barr said. Passengers would hate them, and would resist wearing them on long flights.
“Passengers would find their way around it. They would stick their arm under the shoulder or something like that,” he said. “It might be self-defeating ... The unintended consequence would be that people would not use them, and flight attendants would end up arguing with them the whole flight.”
First published July 10 2013, 1:28 PM