It gives manufacturers 18 months to five years, depending upon the plane involved, to develop inspection programs. Airlines and other operators then have another two and a half to six years to implement the inspection requirements.
Bill Voss, president of the Flight Safety Foundation in Alexandria, Va., said an FAA safety order to be issued Tuesday is an acknowledgement that previous inspection procedures were inadequate. "There is no question this was a very serious safety event," Voss said.
That the skin peeled away shouldn't come as a surprise, said Paul Czysz, professor emeritus of aeronautical engineering at St. Louis University.
Czysz said fuselages are designed with a specific stress limit, based on the number of cycles a plane flies. When a fatigue crack emerges, he said, that means the limit is being pushed. The trick is to keep up a rigorous inspection program.
"It's not magic," he said. "It's just basic physics."
Lowy reported from Washington. Associated Press writers David Koenig in Dallas, Joshua Freed in Minneapolis and Scott Mayerowitz in New York also contributed to this report.