FORT WORTH, Texas (CBSDFW.COM/AP) – American Airlines scored a victory in court Monday over two unions representing mechanics who the airline says are taking part in an illegal work slowdown.

A federal judge ordered the unions to tell workers to take all steps to avoid interfering with American’s operations.

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U.S. District Court Judge Charles McBryde found merit in statistics compiled by American showing that starting earlier this year, workers began taking longer to fix planes and delayed more tasks.

The judge wrote the only reasonable explanation was mechanics were acting deliberately to gain leverage in contract negotiations.

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American sued the Transport Workers Union and the International Association of Machinists and Aerospace Workers in May.

The unions denied wrongdoing.

Southwest also sued its mechanics’ union this year, then settled on a new contract.

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