American Airlines has cut its full-year profit forecast, blaming an estimated $350m (£270m) hit due to the grounding of its Boeing 737 Max aeroplanes.
The airline cancelled 15,000 flights using its two dozen 737 Max jets up until late August.
Aviation regulators around the world grounded the 737 Max fleets after two crashes on the aircraft killed 346 people.
American Airlines said it was confident the jets would resume flying in August.
Before that can happen, plane maker Boeing must develop a software fix for the 737 Max and new pilot training for regulatory approval by the US Federal Aviation Administration.
American Airlines also said its fuel expenses for the year would now be $650m more than previously expected, due to rising oil prices.
The largest airline in the US by passengers carried said it now expected its 2019 adjusted profit to fall between $4 and $6 per share, down from a range of $5.50 to $7.50 per share.
For the first quarter, which was not totally affected by the grounding of 737 Max jets, net profit was $185m, up from $159m for the same period in 2018.