WestJet Airlines Ltd. earned $13.8 million in the first quarter, down 63 per cent from the same time last year.

Part of the drop was related to the departure of the company's chief executive officer, the Calgary-based airline said Tuesday. The first quarter included a $3.7-million expense related to the resignation of Sean Durfy, who surprised analysts and investors in March when he left as president and CEO, citing personal reasons.

Net income amounted to 10 cents per diluted share, including special items. That's down from $37.4 million or 29 cents per share in the first quarter of 2009, when the company got a $2.2-million boost from a tax-related special item.

New CEO Gregg Saretsky expressed satisfaction with the quarter's profitability, "especially in light of the challenging economic environment and rising energy costs."

WestJet's revenue improved to $619.8 million in the first three months of this year, up seven per cent from $579.3 million in the first quarter of 2009.

Fleet capacity grew by 7.9 per cent in the quarter due to expansion into more southern markets, the company said in a release.

Revenue per available seat mile, a key airline performance metric, declined slightly but WestJet said it sees encouraging indications of a stronger load factor and improving yield trends.

Assuming this trend remains, "the airline expects to see year-over-year [revenue per available seat mile] gains in the second quarter of 2010," the company said.

WestJet also noted improvements in its on-time performance and number of claims for delayed or lost baggage.