Doors on both engines of the British Airways plane in last week's Heathrow emergency landing drama had been left unlatched during maintenance, according to an official accident report .
The unlatching had not been identified before the Oslo-bound Airbus A319 took off with 75 passengers and five crew on May 24, said the report from the Air Accidents Investigation Branch.
The fan cowl doors from both engines detached as the aircraft left the runway at Heathrow, puncturing a fuel pipe on the right engine, the report said.
The detaching also punctured the airframe and some aircraft systems and the flight crew, led by the 50-year-old captaain, elected to return to Heathrow.
On the approach to land an external fire developed on the right engine, with the left engine continuing to perform normally tfhroughout the flight.
The report added that the right engine was shut down and the aircraft landed safely. The emergency services quickly attended and extinguished the fire in the right engine.
Passengers and crew evacuated the aircraft via the escape slides, without injury.
The report said: "Subsequent investigation revealed that the fan cowl doors on both engines were left unlatched during maintenance and this was not identified prior to aircraft departure."