(Adds operating expenses, fuel costs, background on joint venture)
Feb 6 (Reuters) - WestJet Airlines Ltd's revenue rose 10 percent in the fourth quarter as the Canadian carrier flew more passengers.
Canada's second largest airline said on Tuesday revenue passenger miles a measure of passenger traffic rose 8.8 percent to C$6.33 billion ($5.05 billion) in the quarter ended Dec. 31.
WestJet has worked on growing its fleet and attracting more customers as it locks horns with rival Air Canada.
The company recently began a joint venture with U.S.-based Delta Air Lines and expects to launch an ultra-low-cost-carrier called Swoop in June.
However, WestJet's fuel prices jumped 19.5 percent year-over-year in the fourth quarter, sending operating expenses up 11.5 percent to C$1.04 billion.
Net earnings fell to C$48.5 million from C$55.2 million a year earlier.
Excluding one-time items, WestJet earned 42 Canadian cents per share, in line with analysts' average estimate, according to Thomson Reuters I/B/E/S. ($1 = 1.2541 Canadian dollars) (Reporting by Anirban Paul in Bengaluru; Editing by Savio D'Souza and Sai Sachin Ravikumar)