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May 2 (Reuters) - Canada's WestJet Airlines Ltd WJA.TO reported a better-than-expected quarterly profit on Tuesday as it flew more passengers, and said it agreed to buy up to 20 Dreamliner aircraft from Boeing (NYSE:BA) Co BA.N .
The Calgary-based airline said it flew 5.7 million passengers in the first quarter ended March 31, up nearly 7 percent from a year earlier.
Load factor, which measures how effectively an airline fills seats, rose to 83 percent in the quarter from 82.1 percent a year earlier.
However, aircraft fuel costs jumped 41.5 percent to C$235.5 million ($172.3 million), hurt by higher crude prices, squeezing profit margins.
WestJet, Canada's second largest carrier, said the deal with Boeing includes commitments for 10 787-9 aircraft to be delivered between the first quarter of 2019 and December 2021.
The company has options to buy 10 more aircraft, to be delivered between 2020 and 2024.
The deal comes as the airline seeks to upgrade its fleet with more fuel-efficient aircraft.
WestJet's net earnings fell to C$48.3 million, or 41 Canadian cents per share in the first quarter ended March 31, from C$87.6 million, or 71 Canadian cents per share, a year earlier. items, WestJet earned 56 Canadian cents per share, according to Thomson Reuters I/B/E/S, beating analysts' average estimate of 50 Canadian cents.
WestJet's revenue rose 8 percent to C$1.11 billion. ($1 = 1.3669 Canadian dollars)