It was the third time in 18 months that Northwest, the nation's fourth-largest airline, has invoked force majeure.
At the same time, mechanics at Northwest Airlines, the country's fourth-largest airline, have been waiting four years for a new contract.
Northwest, the country's fourth-largest airline, dominates air service in the upper Midwest and middle South.
Both Northwest, which is the country's fourth-largest airline in terms of revenue, and the pilots have repeatedly expressed their determination to reach a settlement.
Northwest, the nation's fourth-largest airline, would not discuss billings, but it is estimated that they could reach $90 million in the next year.
But it is still far from clear that the troubled carrier, the country's fourth-largest airline, will wind up a winner.
Still, Northwest, the nation's fourth-largest airline, recently used up the last part of a $600 million line of credit set up by its banks.
It was the fourth-largest airline in the US based on revenue passenger miles.
Mr. Davis has been bidding for the nation's fourth-largest airline since March 28, when he made his $2.7 billion offer directly to the company's directors.
Northwest is the nation's fourth-largest airline; Eastern is No. 7.