The Teamsters union is stepping up its campaign to unseat other unions in the airline industry.
Teamsters officials said Tuesday that they filed a petition with a federal labor agency to force an election against the Transport Workers Union to represent mechanics at American Airlines.
The Teamsters union is also seeking to represent mechanics at US Airways, who are currently represented by the machinists' union.
The outcome of both elections will determine which union will negotiate with the world's biggest airline. American and US Airways expect to close their merger deal in the next few months and create a carrier larger than industry leader United Airlines.
The Transport Workers and the International Association of Machinists and Aerospace Workers said this month they would share representation of mechanics and other ground workers after American combines with US Airways. That plan, however, would be upset if either loses an election to the Teamsters.
By law, the Teamsters need the support of at least half the American Airlines mechanics to force an election. Union officials declined to say how many signatures they got. There are more than 10,000 mechanics at American.
Hank Rogish, an American Airlines mechanic in Fort Worth who is working on the Teamsters' campaign, said workers are frustrated about concessions that the Transport Workers Union, or TWU, made during contract negotiations in the 1990s, 2003 and 2012.
Rogish said that when American Airlines, operating under bankruptcy protection since November 2011, closed a maintenance hangar in Fort Worth, "there wasn't a word from TWU." The Teamsters, he said, "just don't allow their members to be decimated like TWU."
A TWU official called the Teamsters "a rogue union" that has targeted other unions instead of organizing nonunion workers.
Garry Drummond, the director of TWU's airline industry group, said the Teamsters lost more members than any U.S. union last year and "has resorted to raiding established unions at American Airlines and US Airways" to gain enough new members to bolster its pension plans.
Drummond said the Teamsters had done "a terrible job" for other aircraft mechanics, pointing to United's outsourcing of maintenance of its largest jets. He said that TWU had managed to keep most of American's maintenance work in-house.
Teamsters officials defended their challenges to existing unions.
"We didn't go out looking to organize at the Transport Workers Union or at US Airways," said Teamsters airline-industry organizer Chris Moore. The workers, he said, approached the Teamsters.