An unsecured engine door panel fell off a passenger plane and damaged a wing as it was taking off from Southampton Airport, a report has revealed.
Before departure on 22 April this year the captain had inspected the plane, including a check that the engine panels were secure.
The report by the Air Accidents Investigation Branch (AAIB) concluded the door had not been properly secured.
The Flybe plane landed safely. None of the 40 passengers was injured.
The report also said no abnormalities were found by a de-icing crew who had worked on the Dash 8 plane before it left.
Latches fully open
A pilot sitting in a parked aircraft saw the panel thrown upward from the plane as it left Southampton in the morning.
He reported this to air traffic control (ATC), which passed the information to the flight crew.
The AAIB said: "Other than the report from the ATC, the flight crew were not aware of anything unusual.
"The aircraft appeared to behave normally."
ATC advised the crew that a panel and some other debris had been found on the airfield and the captain decided to return to Southampton where the aircraft landed without further incident.
The report said the panel had damaged the leading edge of the right wing of the plane.
The engine door panel was found in grass near the runway. Two of its latches were fully open and had dirt and grass in them, "indicating they were in the open position when the door impacted the ground".
The AAIB said "evidence suggested" that the door had not been fully latched following maintenance work done at Southampton overnight before the flight.
The report said the Exeter-based airline had launched a safety campaign to highlight the importance of securing and checking engine access doors on all its aircraft.