Full planes were good to US Airways in the first quarter.

The nation's fifth-largest airline on Tuesday posted a bigger adjusted profit as it carried more passengers, and collected more from them.

Automatic government spending cuts hurt demand from government travelers, who account for about 3 percent of US Airways revenue. Revenue from government travelers dropped 37 percent in March, when the spending cuts kicked in. The airline has a hub at Reagan National Airport in Washington.

However, "leisure demand has remained quite strong thus far in 2013," President Scott Kirby said on a conference call. Bookings for May are higher than at the same time last year, he said.

The airline earned $44 million, or 26 cents per share. Its adjusted profit was 31 cents per share, topping the expectations of analysts polled by FactSet.

Revenue rose 3.5 percent to $3.38 billion, driven by what the airline called "a strong demand environment."

The airline earned 28 cents per share in the year-ago quarter, but that was inflated by a swap with Delta that gave US Airways more landing rights in Washington in exchange for giving up rights at New York's LaGuardia airport.

Traffic rose 4.4 percent, pushing occupancy up by 2.4 percentage points, to 81.7 percent.

Fuel prices fell by 3 cents per gallon, to $3.24.

US Airways plans to merge with American Airlines. The combined airline would be the biggest in the world. US Airways said it still expects the deal to close by the end of September, and it's hoping to code-share on American's flights within six weeks of that. Code-sharing allows airlines to sell seats on each other's flights, which makes it easier and more attractive for passengers to book flights that involve both airlines.

Shares of Tempe, Ariz.-based US Airways Group Inc. rose 79 cents, or 5.1 percent, to $16.31 in afternoon trading.