An Aer Arann flight from Luton to Galway with 50 passengers on board, including a baby, was forced to divert to Shannon after one of its engines shut down, a report has found.
The flight crew had to send a 'PAN' call, an urgent message concerning the safety of the aircraft, although a lower level call than "mayday", which indicates distress. The engine shut down due to a lack of fuel and problems gauging the fuel on board due to a technical fault.
Problems with the left-hand fuel gauge on the plane may have been present for more than five weeks, but none of these were recorded in the aircraft's technical log, the report found.
The Department of Transport's Air Accident Investigation (AAIU) unit today published its final report into an incident involving the ATR 42 aircraft registered EI-CBK near Dublin on August 8th two years ago.
No one was injured during the events, but the AAIU made six safety recommendations in its report.
AAIU investigator Graham Liddy found the right-hand engine of the plane shut down due to an absence of fuel feeding that engine.
His report said: "Common sense, prudence and good airmanship would indicate that the fuel tanks should have been dipped prior to each take off when there was any concern that the gauges were faulty or inaccurate, but particularly after any refuelling and most especially when difficulties were encountered during the refuelling or when standard method of refuelling could not be performed.
"Such precautions were not taken on the day in question, except on the occasion of the refuelling at Waterford. If the tanks had been dipped after the Luton refuelling, this serious incident would undoubtedly have been avoided."
The AAIU noted that the crew "undoubtedly had a long and difficult day". Their schedule had been disrupted by changes and also by fog, which also caused air traffic control delays.
They also faced a problem with incorrectly loaded baggage and with a search for pills belonging to a passenger with epilepsy. A lack of technical resources at airports also meant the flight crew was "faced with considerable difficulties in resolving technical problems with the aircraft", the investigators said.
On an earlier leg of the aircraft's tour of duty, the captain had inadvertently taken on just half the fuel he had intended to. Then during refuelling at the end of the next leg, he had inadvertently filled all the fuel taken on board into the left-hand tank.
Part of the reason for the problem was that the captain had to stand out on the wing to manually open a valve and he could not properly see the refuelling lights on a control panel.
The investigators expressed their concern about the practice of maintenance and flight crews of standing on the doors and were later told by the aircraft manufacturer that the doors were not designed for such loads and should not be used for this purpose.
Aer Arann notified the AAIU that a notice had been issued to maintenance staff that the practice was not allowed. The airline also put in place a revised system for so-called "defect deferral", when defects were noticed, but not fixed on the spot.