As US probes airline collusion, American Airlines announces cut in 2015 growth plans

American Airlines is scaling back its plans for more flying this year amid signs that average fares are declining, and the announcement set off a rally in airline stocks.

Wall Street analysts have been urging the airlines to scale back growth plans to prevent fares from falling, but it was unclear whether airlines would continue to talk about their capacity plans after last week, when the U.S. Department of Justice began investigating possible collusion among the carriers.

Shares of American Airlines Group Inc. rose $1.92, or 4.8 percent, to $41.59 in morning trading.

American said Friday that it expects to increase passenger-carrying capacity by 1 percent this year, down from an earlier forecast of 2 percent. American, the world's largest airline operator, said its U.S. capacity will rise 1 to 2 percent and international capacity will rise about 1 percent compared with 2014.

The signal comes a week after the Justice Department began an investigation into whether American and rivals United, Delta and Southwest are violating antitrust laws by working together to limit seats, which would drive up fares. Investigators have asked the airlines for information about their discussions about capacity with each other, with Wall Street analysts, and with big investors.

Fort Worth, Texas-based American, which also owns US Airways, disclosed the capacity update in a regulatory filing Friday along with releasing details of its June operations.

The company said that a key revenue figure would be down by between 6 and 8 percent in the second quarter from the same period last year.

A decline in the statistic, revenue for each seat flown one mile, usually indicates lower average fares.

Traffic on American, US Airways and their regional affiliates rose 2.8 percent, as passengers flew 20.4 billion miles last month. Capacity increased 2.4 percent — that usually means more flights, bigger planes or both — so flights were a bit more crowed. The average flight was 85.4 percent full, up from 85.0 percent in June 2014.

The company left unchanged its forecast that second-quarter pretax profit margin excluding one-time items would be between 16 and 18 percent.