PARIS — Airbus confirmed Thursday that new cracks had been found in the wing ribs of a small number of its twin-deck A380 planes, a discovery that industry officials said would most likely prompt European safety regulators to order mandatory inspections across the superjumbo fleet as a precaution.
Less than two weeks ago, tiny cracks were found in a different part of the same wing component of five A380s, including planes flown by Qantas Airways and Singapore Airlines.
The problems are viewed by the European Aviation Safety Agency as significant enough to merit closer inspection of a large number of the 68 A380s in service with seven airlines, said the industry officials, who requested anonymity because the regulators’ recommendations were not expected to be made public until Friday.
The new hairline cracks have so far been found on just two planes, both of which are owned by Emirates Airlines, said one person close to the situation who requested anonymity because he was not authorized to discuss the inspection process. Emirates is the largest customer for the 555-seat A380, with 20 of the jets in service and 70 more on order.
David Moore, an Emirates spokesman, declined to comment on the cracks but said the airline was “anticipating an update” soon from the safety agency with regard to the A380 fleet.
All of the cracks have been found in L-shaped brackets that connect the wing’s aluminum skin to its structural ribs, which are made of a combination of metal and lightweight, plastic-based composite materials. About 40 brackets — each about eight inches long — are on each rib with a total of 2,000 brackets spanning each wing of an A380.
Airbus described both cracking problems as minor and said that while the brackets needed to be replaced, they did not pose an imminent safety risk.
Justin Dubon, an Airbus spokesman, said the company had established an inspection and repair procedure in coordination with the safety agency to address the cracking, which he said was linked to unforeseen stresses placed on the wings during the manufacturing process and not to a design problem.
“Both types of cracks have been traced to the manufacturing process, and those practices have now been changed,” Mr. Dubon said. All of the A380s’ wings are built at an Airbus plant in Broughton, Wales.
The first cracks were found late last year on the wing of a Qantas A380 that was being refurbished after experiencing a spectacular midair engine explosion in 2010. Airbus deemed the cracks — which extend from a bolt hole in the bracket — to be “noncritical” and advised airlines to inspect and replace the parts during routine scheduled four-year maintenance checks. The first A380s entered service four years ago.
Only nine A380s have undergone the recommended inspections thus far, Mr. Dubon said. But in the course of those inspections, two planes were found to have tiny fissures in a different section of the wing bracket, he said, without identifying the operators of those aircraft.
According to people with knowledge of the regulators’ deliberations, an accelerated inspection and repair procedure was likely to be ordered only for those A380s that had completed the highest number of takeoff and landing cycles since entering service in late 2007.
Operators of the rest of the fleet will be advised to make the inspections and any needed repairs during the next regularly scheduled maintenance check, these people said.
Fatigue cracking is unusual in relatively young aircraft. The phenomenon, which is more common in older planes that have experienced heavy use, has begun to attract closer regulatory scrutiny in the wake of a recent series of incidents involving aging Boeing 737s and 757s in the United States.
In one case last year, a tiny undetected crack in the metal skin of a Southwest Airlines jet widened into a five-foot hole in the fuselage that forced the plane to make an emergency landing.
Dominique Fouda, a spokesman for the safety agency in Cologne, confirmed that the agency was working “in the direction” of requiring inspections of some A380s by the end of the week, but declined to discuss the details.
This article has been revised to reflect the following correction:
Correction: January 19, 2012
An earlier version of this article incorrectly described the construction and placement of the brackets needing inspections. In addition, there are seven, not 15, airlines that use the A380s currently in service.
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