Profits by U.S.-based airlines have been rising, but so have complaints by air travelers.

The number of complaints filed by air travelers with the U.S. Department of Transportation jumped 30% in 2015 over the previous year, with complaints about airfares nearly doubling, according to data released Thursday by the federal agency.

Air travelers filed 20,170 complaints in 2015, compared with 15,539 complaints in 2014, with the greatest number of complaints filed against American Airlines, the nation’s largest carrier. Complaints over fares nearly doubled to 1,813 in 2015 from 916 in 2014.

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Spirit Airlines, the Florida ultra-low-cost carrier, had the highest rate of complaints, 11.73 complaints for every 100,000 boarding passengers, according to the Department of Transportation. By comparison, the 13 largest U.S. carriers had an average complaint rate of 1.90 complaints for every 100,000 customers.

A Spirit spokesman attributed many of those complaints to weather problems that kept pilots and flight attendants from staffing planes in June. Spirit also had an unusually high number of complaints from first-time customers, who gripe when they learn they have to pay a fee for a carry-on bag or beverages, Spirit spokesman Paul Berry said.

“We are making an effort to improve on these issues, and I think this time next year, you will see the number improve considerably,” he said.

Thanks largely to a steep decline in fuel costs, the nation’s airlines have been reporting near-record profits. Over the past year, the cost of jet fuel has dropped 40%, according to the International Air Transport Assn., a trade group for the world’s airlines.


In the three months ended Sept. 30, U.S.-based carriers reported a net profit of $9.3 billion, up from $3.1 billion in the same period in 2014, according to the Department of Transportation.

Airlines for America, a trade group for the nation’s carriers, noted that the number of lost or damaged bags dropped in 2015, and on-time arrival rates for airlines improved.

As for passenger griping, trade group spokesman Vaughn Jennings said the rate of complaints remains relatively low, considering that the airlines carry more than 2 million passengers a day.

To read more about travel, tourism and the airline industry, follow Hugo Martin on Twitter at @hugomartin.


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