Six months after the Federal Aviation Administration levied a fine against Southwest Airlines for safety violations related to airplane repairs, the agency announced it was investigating similar issues with American Airlines Group after mechanics filed a series of whistleblower complaints and a lawsuit alleging managers for the airline breached FAA rules in order to aid its merger and get planes on the tarmac.

The Wall Street Journal reports that the FAA is investigating improper maintenance compliance allegations against American after seven maintenance workers filed two federal whistleblower complaints and leaders of the Transport Workers Union Local 591 filed a lawsuit against the airline alleging maintenance fraud and antiunion actions by managers.

The union lawsuit [PDF], which was filed on Thursday in the U.S. District Court for the Northern District of Illinois, claims that more than 20 American aircraft have flown passengers while “in an unairworthy condition,” meaning the planes did not meet federally mandated repairs and inspections.

However, the suit does not specify what was wrong with the planes. The FAA does allow airlines to temporarily operate aircraft that have nonessential maintenance issues.

Officials with American denied the allegations of the suit, saying that the FAA has not brought any airworthiness issues to its attention.

In addition to the lawsuit, seven American mechanics – six from Chicago and one from Dallas – filed two federal whistleblower complaints against the airline alleging that managers pressured the employees to breach federal rules on aircraft maintenance related to wing cracks and inspections for suspected lightning strikes.

The whistleblower complaints claim the company and managers intimidated union representatives from aiding the FAA investigations into the matter claiming it could complicate the company’s merger integration with U.S. Airways.

Officials with American tell the WSJ that the airline is continually in contact with the FAA to ensure aircraft maintenance, safety and regulatory compliance is “second to none.”

The mechanics also accuse managers of wanting to bypass some safety procedures set forth by the FAA in order to keep the airline’s operations running on time.

For example, the mechanics claim that in September 2014, Chicago mechanics flagged maintenance issues that took seven planes out of service. The following day an American manager allegedly scolded the employees for flagging too many issues.

The mechanics claim the manager told them they had to “strike a ‘balance’ between compliance with federal aviation maintenance standards and what the manager termed ‘performance’ because ‘I need my planes to go out in the morning.'”

David Seymour, American’s senior vice president who oversees maintenance for the airline, tells the WSJ that he hasn’t seen any of the issues at play.

“We’re just not seeing it; we’re not hearing it,” he says. “We spend a lot of time with groups out there and we’re not seeing the same things that…are being alleged.”

The complaints accuse American managers of prohibiting mechanics from initiating required inspections of aircraft to look for potential damage from lightning strikes unless a pilot reports an actual strike.

A person familiar with the issues tells the WSJ that the FAA has preliminarily determined that in some instances, American’s lightning-related inspections didn’t comply fully with federally mandated procedures.

Also in the complaints, employees accuse American managers of retaliating against the seven American mechanics who reported their supervisors for not following required maintenance procedures.

The six mechanics from Chicago say they were reassigned to work on one aircraft to limit their effect on American’s operations.

According to the WSJ, this isn’t American’s first issue regarding FAA maintenance mandates. Back in 2013, the company settled $160 million in pending civil penalties. In all the company, paid $24.9 million in exchange for safety and maintenance improvements, including pledges to strictly comply with written procedures for all maintenance tasks.

Unit of Mechanics Union Sues American Airlines [The Wall Street Journal]

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