The Federal Aviation Administration required engine fixes on the Boeing 737 model, but airlines had until July 2028 to complete them. Accident investigators probing a Ryanair plane that experienced engine failure while flying over Greece last month found bird remains inside an engine.

In the July 10 accident, engine parts pierced the jet’s fuselage and dislodged a window, seriously injuring a passenger. A preliminary report by the National Transportation Safety Board (NTSB) released Thursday said bird remains, including feathers, were found inside certain components of the engine, which suffered a broken fan blade.

The separated fan blade resulted in damage to portions of the engine’s cover and sent engine fragments flying. The airplane’s cabin depressurized, and the passenger in seat 11F got partially lodged where the dislodged window had been. Other passengers managed to pull the injured passenger back into the cabin. One tried to block the blown-out window hole with a metal box.