Contrary to popular belief, most airliner accidents are survivable. Many crashes are relatively slow impacts where the forces on the passenger can be similar to those involved in a car accident. So it makes sense the airlines are borrowing technology from the automotive world that has been protecting drivers for years.
Bill Hagan is fairly blunt when he describes the problem for many of the seating areas inside of an airliner, “you have objects that are not friendly head strike surfaces.” Hagan is a former General Motors engineer who is now the president of AmSafe Aviation, the company that makes 95% of the seatbelts used on commercial airplanes. Today his company is leading the way in implementing the use of airbags for airline passengers.
When you talk to somebody like Hagan who is responsible for designing safe occupant spaces in aircraft, you hear terms like “head strike surface” quite a bit. At first these terms create an image that isn’t so pleasant. But new regulations set to take effect at the end of this month are aimed at increasing the margin of safety for the flying public. And this means many more airliners will be reducing those unfriendly head strike surfaces by using airbags in places that have bee problematic for engineers designing airplane cabins, such as the front rows next to bulkheads and some of the reclining and bed-like seats used in first class cabins.
The new requirements go into effect on October 27 and will require all new airliners rolling off the assembly lines to meet new FAA rules to protect passengers in the event of a crash. Under the new rules, seats must be able to withstand 16 times the force of gravity without deforming or pulling out of the tracks in the floor and passengers must be protected to this 16g requirement. Many airliners are already equipped with the 16g seats, but until now, only entirely new designs created after 1988, such as the Boeing 777, have been required to meet this standard.
A large percentage of airplane crashes occur during take off and landing when speeds are relatively low and the aircraft usually meets the ground at a oblique angle, “most are very survivable crash events” Bill Hagan says.
One of the problems is that in some seating areas the passengers are exposed to surfaces that do not absorb energy in an impact, these are the not so friendly head strike surfaces. In the event of a crash, most passengers are protected by the seat back in front of them which is designed to fold over forwards, absorbing much of the energy. But at the bulk head or behind the immovable exit row seats, there is nothing to absorb the energy. Airlines could remove seats to meet the new requirement, but that would mean lost revenue. So instead, many are opting for the seat belt mounted airbag to meet the 16g standard.
In the beginning Hagan explains, the challenge for the engineers was how to mount airbags on the aircraft itself, similar to how airbags are mounted to a dashboard, “but every interior is different, it’s not practical.” The simple solution was to put the airbag in the seat belt. This not only simplifies the problem of where to place the airbag, it is safer according to Hagan, “the airbag inflates away from the occupant where it can’t induce an injury.”
In addition to protecting bulkhead and exit row passengers, the seat belt airbags have allowed airlines to develop several creative seating arrangements. One example is the pod type seats used by Singapore Airlines in the Boeing 777. During development, the airline was having trouble meeting the 16g requirement for the first class seats, “they had a lot of head strike problems” says Hagan. But by using the seat belt airbag, the airline was able to meet the safety requirements. The airbags are now the norm on many airlines using similar premium seating arranegments.
Tomorrow Autopia will look at some of the creative seating arrangements of the future. Some are sure to cause frequent fliers to smile, others may elicit a frown.
Image/Video: AmSafe Aviation