The Transport Workers Union in Tulsa announced that jobs are at risk despite the American-US Airways merger.
The Dale Danker, TWU514 president, wrote in a statement on the union's website that on Monday, the union was given information on the upcoming changes.
According to the statement, the merger would keep the Tulsa base at 90 percent capacity for two years.
"...the company information showed we should prepare for a surplus of no more than 400 positions around the first quarter of 2014," Danker said. "This surplus would likely include all title groups. In addition, they are planning to give the airline additional aircraft for the peak summer flying months, which would create a temporary surplus during the summer of 2014. We did discuss some options to address the summer surplus, such as allowing more vacation use during the summer."
Danker went on to say that the union leaders were working to "...persuade the company to source work in-house rather than continue to source it out."