The Havilland DHC8-Q400, destined for Fiumicino-Leonardo da Vinci International Airport, Italy, took off at 7:30am local time.
A few minutes into the flight, the pilots were aware of a problem with the flaps and returned to Luxembourg’s Findel airport.
According to website crash-aerien.aero, the plane landed without incident. Experts were examining the aircraft to determine the cause of the fault.