AMR Corp.'s American Airlines asked a federal judge to stop a union-representation election scheduled to take place among passenger service employees at the carrier, Bloomberg News reported yesterday. In a district court filing on Monday, American requested a court order preventing the National Mediation Board from holding what the airline called an "illegal" election. American, which sued the board in May over its decision to order an election, said that the agency "completely disregarded that its very statutory authority to act was at issue" in the litigation. The board has asked the court to dismiss the company's complaint.