American Airlines has gone to court for an injunction against their mechanics’ union, accusing them of a work slowdown leading to “650 flight cancellations and more than 1500 maintenance delays” affecting 125,000 customers, according to a letter sent to employees. They contend that the degree of issues they’ve faced would be “one-in-one billion” if left to chance rather than the result of “concerted activity.”

There’s still no joint maintenance contract for US Airways and American Airlines mechanics. Negotiations have been contentious, and are currently in mediation.

• American wants to be able to do more outsourcing. They promise current workers will keep their jobs and pay and work locations, but the average age of mechanics is in the mid-50s and American wants to be able to shift work elsewhere over time — as United and Delta do.

• American wants lower health care costs. They want to move US Airways mechanics over to the legacy American plan.

• There doesn’t seem to be a strong reason for mechanics to agree to these changes. American Airlines gave employees across the board raises without insisting that changes be part of a contract. The airline says that’s made it harder to get mechanics to agree to a deal. More money remains on the table with a new deal, but it’s less of a difference than it otherwise would have been.

The carrier is offering terms they say are more costly than what United and Delta have with their mechanics, so a common refrain from management has been that they would happily sign either the United or Delta deal today. Workers say they don’t want a concessionary contract.

I spoke to executives last fall who believed there was a maintenance slowdown in place, and efforts to write up issues unnecessarily. Unions are much more careful than they used to be about illegal job actions.

Twenty years ago the American pilots union was fined $45 million because there was written proof they were encouraging a sick out than led to as many as a quarter of the airline’s pilots calling out at a time over a ten day period. During American’s bankruptcy pilots engaged in a work slowdown, but there wasn’t tangible proof.

Regardless of where this court action goes, it’s indication of the extent to which negotiations have become acrimonious and it’s not surprising that the airline’s operation suffers. Southwest Airlines just signed a rich new deal with its own mechanics after facing a slowdown of their own.

Here’s American’s letter to employees about the injunction they’re seeking: