An EasyJet Airbus A320 that lost part of the composite fan cowl on Aug. 12 shortly after takeoff had received routine overnight maintenance the night before, says the airline.

An airline spokeswoman says a fan cowl over the left-hand CFM International CFM56 engine detached from the four-year-old aircraft during takeoff from Milan Malpensa Airport but the aircraft returned to the airport and landed with power from both engines.

This incident follows a more serious one on May 24 when the inboard and outboard cowl doors detached from a British Airways Airbus A319 after departing London Heathrow Airport for Oslo. That aircraft suffered damage to fuel and hydraulic systems, the fuselage and landing gear door. A scheduled overnight check on this aircraft required opening the fan cowl doors on both engines to check the integrated drive generator oil levels.

EasyJet immediately launched an investigation of the incident and is working with the safety authorities.

The airline operates 214 A319 and A320 aircraft that have an average age of four years. “This is the first incident of its type EasyJet has experienced,” says the airline.

All of the passengers safely disembarked the damaged aircraft and continued their journey to Lisbon on a different aircraft, later the same day.