Crashing for Missions
The seat was mounted to the sled; the crash-test dummy was strapped into the seat. This was going to be the big test: 26Gs forward.
There would be 5,000 pounds of force, the weight of a good-size pickup truck, imposed on the seat through its seatbelt and shoulder harness.
And before the seat was crashed, it was distorted at the floor to simulate the way it would warp in a real accident.
Yeah, this was going to be a tough one.
How did JAARS, a mission organization, get into designing seats for a brand new kind of airplane?
The process began in 1976, when one of our pilots broke his back in an accident. He was paralyzed, and still is, from the waist down. JAARS didn’t want to see that happen ever again—so we began searching for ways to make our planes safer.
God brought a man from NASA into the picture, who gave us information on how to build seats that would absorb energy instead of passing it on to occupants. With that information, an engineer at JAARS began thinking about how to apply the technology to our small planes.
After several months, the first prototypes were crash-tested—and each failed. After more design work—and more testing and more failures—the seats were beginning to show that they could save backs and lives. With the financial partnership of a foundation, many JAARS aircraft were retrofitted with these new seats.
Twenty years later, a friend of JAARS felt led by God to design an aircraft specifically for missionary aviation. This man, who had already designed several planes, began discussing the idea with mission aviation groups. Soon, the plans began to gel for the aircraft—which would later be known as the "Kodiak."
But seat design—which is a major effort for any plane—was a problem. The designer came to JAARS and asked if we could help.
Gladly, was our response.
During the next four years, JAARS designed and crash-tested two types of seats for the Kodiak, one for crew members and one for passengers. Both seats use energy-absorbing seat pans, which prevent injury during accidents with extreme amounts of vertical and forward force.
The crew seats also employ additional energy absorbers in the seat frame and are adjustable for added comfort. And while passenger seats are designed to handle great amounts of force during crashes, they can be folded for storage or reinstalled quickly to accommodate passengers.
After years of design work, preliminary crash-testing for the seats took place at the Civil Aero-Medical Institute in Oklahoma City.
The cable was attached to the 7,400-pound weight, which would hurl the sled down the track. It was then attached to the sled. The data collection wires were connected and checked. The special deceleration system was finally ready.
As the sled inched backward, it lifted the weight and engaged the latch at just the right distance to achieve the correct speed—the speed that would stress every part of the seat as if it were a real crash. All personnel were moved to a safe distance from the crash zone. The countdown was started at 10 seconds before the release.
Nine, eight, seven, six ... Everything got quiet.
Five, four ... The first bank of bright lights came on.
Three ... The second bank of lights lit. Two ... The last bank of lights lit, and the high-speed cameras spooled up.
One ... The manager’s hand moved to the release button and pushed.
The sled lurched forward and headed for a certain crash. Two seconds later, there was a bang that rivaled a small cannon. The dummy threw his arms up, as if to say, “Glory I’m glad that’s over!”
The seat had passed the test—just one of many successful tests that would occur before these seats would be eligible for service in the Kodiak.
The Kodiak was certified with these seats on May 30, 2007. JAARS received its first Kodiak in January 2009.
—Terry Heffield is an engineer with JAARS aviation.
