Canada’s civil aviation authority has issued an emergency airworthiness directive to reduce the engine thrust of Airbus A220 aircraft under certain conditions after several engine incidents were reported by pilots.
The directive was issued on 26 October, the directive states that pilots of both the A220-100 and A220-300 models must fly at 94% of full thrust capacity when they are over 29,000ft. It states that the automatic must be disabled before climbing at this altitude.
This follows several reports of engine in-flight shutdowns on a number of A220s. As a result Swiss International Air Lines grounded all of its 20 A220s on 15 October, after three engine thrust incidents. However, operations were resumed after an inspection which found all of the engines to be in “impeccable condition”.
“Preliminary investigation results indicate high-altitude climbs at high thrust settings for the Pratt & Whitney PW1500G engines with certain thrust ratings may be a contributor”, says Transport Canada.
At present A220s are forbidden to fly above 35,000ft by Transport Canada, when weather conditions are prone to icing, as activating the de-icing system at this altitude may overheat the engine, triggering the fire warnings.
Operators now have seven days to comply with the directive. Transport Canada has warned that these are just interim measures and could be followed by additional actions as the current investigation is underway.