NEW YORK (Reuters) - The U.S. pension insurer has appealed a bankruptcy court decision allowing Delta Air Lines Inc. to implement a new pilots' contract that includes payments to pilots in case their pension plan is turned over to the agency.

The contract, which saves the carrier some $280 million a year, was ratified by the pilots last week. The bankruptcy court then approved the agreement between Atlanta-based Delta and its pilots' union last month over objections from the Pension Benefit Guaranty Corp. (PBGC), which opposed provisions under the new contract for certain payments to pilots should their pension plan be terminated. That termination would cut the benefits owed to pilots.

One of the issues on appeal is whether the court can approve a deal that compensates employees for losses resulting from the underfunding of their pension plan, "when all claims for such underfunding belong exclusively to the PBGC," the pension insurer said in a filing in bankruptcy court in New York on Wednesday.

The PBGC is operating under a $22.8 billion deficit after assuming the liabilities of pensions plans. The plans from the airline and steel industries have been a major source of that underfunding.

The deal between Delta and its pilots' union was reached after months of negotiations, and is part of the airline's efforts to raise $3 billion a year through revenue increases and cost cuts.

Delta has been restructuring its business under bankruptcy protection since September last year, after being battered by high fuel prices and competition from discount carriers.

For more on the deal between Delta and its pilots, click here.