Airbus says it has a fix ready for a problem discovered in several of the A380s currently in service. The issue is small cracks in components found within the wing of the world’s largest airliner. The company says the cracks are not a safety issue and it has found the source of the problem.
The cracks were first seen during the inspection of a Qantas A380 that had suffered an in-flight engine failure in 2010 where pieces from the engine had pierced a section of wing. The uncontained engine failure was not related to the small cracks, but it was the first time they were noticed.
The small cracks are found L-shaped brackets that attach the thin aluminum skin of the wing to ribs that form the shape of the wing. There are about 2,000 of these brackets in each wing. If the cracks were to lead to a failure in a single bracket, it is unlikely there would be any safety issue. Airbus has said on several occasions that the A380 is safe to fly. But the European agency that oversees aviation safety has issued an order for inspections of about a third of the current A380 fleet.
The cracks have prompted the European Aviation Safety Agency to issue an airworthiness directive calling for the inspection of A380s that have been in service the longest. The agency says if left undetected and not fixed, the cracks “could potentially affect the structural integrity of the aeroplane” according to Aviation Week & Space Technology.
Airbus has acknowledged the issue and says the finding of cracks in more aircraft over the past week is inline with the expectations based on the cause of the problem. The airplane maker expects cracks will be seen in most A380s that are currently in service.
The company is changing the way the brackets are attached to the ribs reducing the amount of strain applied when the wings are manufactured. Airbus will change the material used to make the L-shaped bracket to a stronger alloy.
According to the EASA airworthiness directive, A380s that have at least 1,800 flight cycles (a takeoff and landing) must undergo an inspection within four days or 14 more flight cycles. Aircraft with 1,300 to 1,800 have up to six weeks or 84 flight cycles for the inspection. About 20 of the 60 A380s in service currently meet the requirement for inspections.
Cracks in aluminum parts on airliners are nothing new. Many aluminum parts develop cracks over time due to the properties of the metal. Airplanes are designed to minimize the stress and strain on aluminum components and engineers are usually able to predict when an inspection, and possible replacement, due to fatigue should take place.
The cracks found in the A380s brackets are an example of unforeseen cracks found in an aluminum part. According to Airbus the new attachment technique and new alloy will restore the massive airliner’s normal expected lifespan of more than 25 years.
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