The results from Delta, the world's third-biggest airline company, produced a strong opening to the industry's results for the busy April-to-June quarter. American and United are scheduled to report second-quarter figures on Thursday, and analysts expect the biggest U.S. carriers to post large profits.
Delta said it benefited from gains in corporate contracts and domestic traffic. Like other airlines, Delta has been adding flights cautiously and instead is cramming more passengers on each plane. The average flight was 86.3 percent full, a figure that would have seemed impossible not long ago.
The average fare per mile climbed 3.8 percent, and Delta also collected more from what it calls merchandising, such as charging extra fees for a roomier seat and for priority boarding.
The company's operating margin climbed to 15.1 percent, and it predicted margins of 15 percent to 17 percent in the third quarter.
For the third quarter, however, Delta predicted slower growth in so-called unit revenue - the amount of money taken in for every seat flown one mile. That figure is closely watched in the airline business, and it jumped 5.6 percent in the June quarter. Delta predicted an increase of between 2 percent and 4 percent for the July-to-September period, compared with the same months in 2013.
For the second quarter, the Atlanta-based company said that net income increased to $801 million, or 94 cents per share, from $685 million, or 80 cents per share, in the same quarter a year ago.
Earnings, adjusted for one-time gains and costs, were $1.04 per share. The average estimate of analysts surveyed by Zacks Investment Research was for earnings of $1.03 per share.
The company said revenue climbed 9.4 percent to $10.62 billion from $9.71 billion in the same quarter a year ago, and beat Wall Street forecasts. Analysts expected $10.59 billion, according to Zacks.
Fuel spending dropped 6 percent to $2.43 billion, offsetting a 6 percent gain in labor costs to $2.05 billion.
Delta shares have risen $10.21, or 37 percent, to $37.68 since the beginning of the year, while the Standard & Poor's 500 index has increased 7.3 percent. The stock has climbed $17.23, or 84 percent, in the last 12 months.
In premarket trading Wednesday, the shares were up 82 cents, or 2.2 percent, to $38.50.