Why a Toronto-bound flight from Amsterdam turned back after five hours in the air

A flight this week from Amsterdam to Toronto spent more than five hours in the air before landing — in Amsterdam. The cause was a missed scheduled maintenance that was discovered while the plane was over the Atlantic Ocean, requiring it to do a U-turn and return home. The aircraft, an Airbus A330-303, had already been delayed 90 minutes from its original departure time of 11:20 a.m. local time, for what should have been an eight-hour flight from Schiphol airport to Toronto. That was due to a last-minute change of plane because the air conditioning on the original one wasn’t working. But the new plane had its own issues. As reported on the website View from the Wing and elsewhere, the crew realized only en route that there was required maintenance for the aircraft that had not been performed. KLM confirmed to National Post that the U-turn was caused by the aircraft reaching what it called a “maintenance deadline.” “During flight KL691 from Amsterdam to Toronto, it was decided to return to Schiphol as a precaution after it became apparent during the flight that the replacement aircraft (PH-AKA) would reach its maintenance deadline,” the airline said in a statement to the Post. “The aircraft was fully airworthy at the time of departure,” it added. “To prevent the license from expiring during the flight, it was decided to return to perform the maintenance in the Netherlands.” The delay — more than three hours on a flight of more than 3,500 kms — means that, due to European laws , each passenger is entitled to 600 euros in compensation, as well as rebooking by the airline. “Although all passengers were rebooked upon arrival, we naturally find it very unfortunate for the passengers who were affected by this,” KLM said in its statement. Flight data from flightradar24.com shows that the aircraft was south of Iceland and nearly midway across the Atlantic when it turned around. Last-minute aircraft swaps have caused issues in the past. View from the Wing details how, earlier this month, American Airlines swapped out a Boeing 787-8 for a similar 787-9, then sent the latter on a flight from Philadelphia to Naples, Italy. But the runway at Naples wasn’t certified for the 787-9, so it had to be diverted to Rome, 200 kms to the north. National Post has reached out to KLM for further comment.

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