The Plain Truth is That, Sadly, Planes Crash Almost Every Day
By: Tim Tomasik
The tragic disappearance of Malaysia Flight 370 has resonated with people around the world and reminds us all of the great importance of aviation safety. Just yesterday, a helicopter crashed and burst into flames near the Space Needle in Seattle, tragically killing two on board.
On October 15, 2013, Spirit Airlines Flight 165, an Airbus A319 transporting 150 passengers, experienced mechanical difficulties and smoke filled the cabin shortly after takeoff. An engine on the Atlanta-bound flight sustained an explosion and failed before returning to Dallas Fort Worth International Airport for an emergency landing. The National Transportation Safety Board (NTSB) stated that it was an “uncontained” engine failure, meaning that broken pieces and parts of the engine escaped the outer engine housing. This is a highly unusual and dangerous occurrence.
Passengers aboard the Airbus A319 reported that they heard an explosion and saw flames come up the side of the plane, lighting up the interior as smoke filled the cabin. One passenger reported: “I saw the engine blow up on the outside of the plane, fire and all that. I’m thinking to myself, I see this on the movies. I’m usually on my couch eating popcorn. This would never happen to me. And here I am 25,000 feet above the ground and this is happening to me.”
The engine explosion led to the NTSB launching an investigation on Spirit Airlines' Airbus Fleet to determine the root cause of the problem, and to determine whether the problem is systemic. The NTSB took possession of the engine, which is manufactured by International Aero Engines (IAE) V2500, a consortium led by Pratt & Whitney.
Over the years, aircraft design methods have moved away from “safe-life,” wherein component parts are installed for a set period of time and then replaced, to a new system that utilizes “damage-tolerant design,” wherein component parts are indefinitely operated so long as they remain within acceptable specifications and damage tolerances. The modern “damage-tolerant system” is more heavily dependent upon adequate inspection, which incorporates a human factors component.
Take, for instance, a crack in a turbine component. Inspectors will compare the damage to manufacturer and FAA regulations to determine whether the component must be replaced. If the damaged component does not exceed these critical measurements, it will stay in service. Of course, a failure of a commercial air carrier to effectively implement scheduled and adequate inspection programs for turbine engines and their component parts can have catastrophic consequences.
In the case of Spirit Airlines Flight 165, the professionally trained crew handled the in-air explosion with great skill and no one was injured. If the “damage-tolerant methodology” that has replaced the “safe-life” system is going to be safe and successful, it is incumbent upon air carriers to ensure that skilled mechanics and inspectors are diligent with adherence to protocols requiring regular inspection and replacement of damaged and failed components.
Maintaining high standards for the maintenance of commercial aircraft is critical to aviation safety. Recent events involving jet engine failures on commercial flights highlight the need for regular and careful inspection of jet engines and their component parts.