AN engine fire which forced a passenger plane to make an emergency landing was caused by an oil supply failure, accident investigators said.
The Flybe flight was en route from Glasgow to Belfast with 76 passengers and four crew on board when its left engine caught fire.
The Bombardier DHC-8-402 plane was diverted from Belfast City Airport to Belfast International Airport, where it landed safely and was evacuated.
A report by the Air Accidents Investigation Branch (AAIB) found that a cracked washer in the Pratt and Whitney Canada PW150A turboprop engine became loose, causing the oil pump to fail.
This resulted in the engine overheating and a fire starting.
The AAIB said that in December last year the engine manufacturer issued an alert requiring internal inspection of engines and a more regular replacement of the washer.
The plane’s two pilots were first alerted to a problem at 6.30pm on December 16 2014 when an oil pressure warning light became illuminated on the flight deck.
After feeling a “judder through the airframe” and hearing a brief fire audio warning they began to turn the plane back towards Scotland, the AAIB said.
Passengers and cabin crew heard three “whooshing” noises and saw a large blue flame coming from the left engine, the report stated.
When the fire warning sounded again the pilots decided to head for Belfast International Airport as it was the nearest airfield.
They used the aircraft’s fire extinguishing systems to put the blaze out, although it restarted shortly before landing at 6.47pm. It was finally extinguished by the airport’s firefighters.
During the evacuation of the plane some passengers were “surprised at the height they were required to jump” because the rear exits did not have slides, the report said.
It added that some passengers fell on landing, receiving “minor cuts and bruises”.
One woman was taken to hospital after suffering from anxiety and chest pains. She was released later that day.
There were no serious injuries.