Un article bien fait concernant la fatigue des 737 Classic ...
Un peu drivé par les sécuritaires de service de l'aviation, ce n'est pas forcément un mal de mettre les agences au pied du mur !
--------- Un lien de Hawaï et un extrait intéressant ----------
Since there are many lap joints in a single airliner, "if you tried to eddy current every lap joint on every plane, the amount of time and energy it would take would be literally staggering," Cox said.
The FAA is also required by law to weigh the cost of the safety procedures it tells airlines to follow against the possible safety benefits. If there is no evidence of a previous safety problem, it becomes more difficult to justify the cost.
"I don't think the public understands the bar that has to be cleared by regulatory agencies," said Bill Voss, president of the Flight Safety Foundation in Alexandria, Va., an aviation industry-funding organization that promotes safety.
Investigators said the tear along a lap joint on the Southwest jet came despite a recent inspection where the plane was taken apart so that inspectors could see into places not normally visible.
They found 21 instances of cracked frames, which are part of the fuselage, or cracked stringer clips, which help hold pieces of aircraft skin together.
Earlier, NTSB investigators said they had found both cracks that were big enough to see with the naked eye but were hidden between overlapping pieces of metal. They said they had also found subsurface cracks.
That's a significant number and should have been a warning to Southwest's maintenance team that there might be more extensive cracking that wasn't detectable by a visible inspection alone, Voss said.
The plane "hasn't just had a lot of cycles, it has had cycles that have put some wear and tear on the structure," Voss said.
Voss compared the inspection process to removing a tumor. Surgeons should "always check around to see if there are any nodes inflamed or whatever else around it. Depending upon what they find, they can go a step further," Voss said.
Hersman noted that at 15 years, the Southwest plane had only reached what is considered midlife for an airliner.
"If we think something needs to be done, whether the aircraft is 15 years old or 50 years old, we will address it," she said.