The new AC would set guidelines for allowing aircraft to continue flying with known structural cracks. The AC would publicize a long-existing FAA policy that deems an aircraft is still airworthy if the crack is not in the primary structure and the airframe can still withstand the ultimate design load.
"The FAA left out the majority of older GA aircraft from this guidance document," said Luis Gutierrez, AOPA director of regulatory and certification policy. "As drafted, it only applies to Part 23-certificated aircraft. But most aircraft flying today were certificated under the old CAR 3 standards.
"It's important that the policy be applied uniformly and predictably to all aircraft in order to keep them flying safely and affordably," Gutierrez said.
AOPA also expressed concern that the proposed AC excludes previously acceptable methods used to substantiate an airplane's ability to sustain ultimate load with cracks in non-critical structure. "The removal of those options from the AC would eliminate viable alternative testing methods with demonstrated success in determining the continued safety of the airframe," said Gutierrez.
Most older aircraft have developed cracks in some structures because of the natural aging process. Although certification authorities in some other countries will ground aircraft with any cracks, the United States has taken the more reasonable position of determining if the crack poses any threat to safety.
July 5, 2005