The European Union’s chief aviation regulator has ordered inspections of 16 Airbus A380 jets after cracks were found in a key wing component on some of the aircraft.

The EU Aviation Safety Agency on Monday ordered five of the jets to be grounded immediately for checks. The 11 others were ordered to seek an inspection within their next 25 flight cycles, an industry term that refers to a single takeoff and landing.

Cracks in the wing beam of certain planes were discovered during previous inspections, the European aircraft maker said Wednesday. According to the regulator, such cracks “could reduce the structural integrity of the wing.”

Neither the regulator nor Airbus named the airlines whose planes are affected.

But some belong to Emirates Airline, which said in a statement that it would “comply and carry out the inspections required in accordance with the airworthiness directive.”

The airline said inspections will commence “within the next 48 hours, and any work required will be carried out before releasing aircraft to service.” The company did not say how many of its jets were affected.

In 2012, the EU aviation regulator ordered urgent inspections of all Airbus A380s due to potential wing cracks. At the time, the worldwide fleet numbered around 250 jets.

There are 173 A380s in active use for passenger flights around the world, according to Cirium, an aviation data firm. Airbus delivered its last A380 in 2021, though commercial airplanes often fly for decades after the final jet rolls off the production line.

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