American Airlines says the Boeing 737 Max grounding will cost $400 million.
It is about $50 million more than the airline had previously estimated.
The airline has been forced to cancel thousands of flights this summer and has removed the jet from schedules until at least November 2.
Still, the airline announced second quarter profit was up 19% to $662 million.
The workforce ‘did a tremendous job to deliver solid results despite a challenging start to our summer,’ said CEO Doug Parker.
Revenue was up 3% to $11.96 billion, and operating costs only rose by 2%, thanks to lower fuel prices.
When the Max does eventually gain clearance to fly again, Parker is sure customers will feel comfortable flying on it, although many in the industry do not share his confidence.
"Our pilots believe they are adequately trained to fly the aircraft. That will make the difference in consumer attitudes about the aircraft itself," he said.
The Max was grounded in mid-March after two deadly crashes claimed 346 lives.
