Ask anyone "How was your flight?" and you'll likely hear some kind of complaint: It was late, my luggage was lost, there was no legroom.
And it appears that more airline passengers are not just sounding off to friends and family, but are filing official complaints with the government.
New figures from the U.S. Department of Transportation show a large increase in the number of consumer complaints against airlines last year, even as the airlines are showing slight improvements in on-time performance and how well they provide other services.
The DOT's Aviation Consumer Protection Division reports that it received more than 20,000 complaints from travelers against airlines last year, compared to a little more than 15,500 in 2014.
The most frequent complaints are about flights being delayed or canceled and luggage that is lost or damaged, even though government data show airlines slightly improved their on-time performance last year and lost fewer bags.
Complaints spiked in December of 2015, with DOT recording 1,565 complaints from angry airline customers, an increase of almost 47 percent from December 2014, and up nearly 20 percent from November 2015.
Last year, airlines improved on-time performance from 2014, with 79.9 percent of flights arriving on time in 2015, compared to 76.2 percent of flights being on time the year before. But that's still one in five flights arriving late, a chronic problem in the industry.
One reason the number of complaints rose last year could be that more travelers are aware that they can complain to the government and are finding out how to do it.
It's not something that the airlines are all that eager to tell their customers about. Customer service representatives rarely volunteer the information over the phone or at airport counters, and the information is very difficult to find on airline websites.
But that could soon change.
Rep. Janice Hahn, D-Calif., is trying to require airlines to post the consumer complaint hotline and a link to the DOT's complaint Web page in a prominent place on their websites. She was able to add the provision to the Federal Aviation Administration funding bill that passed the House Transportation committee last week.
Complaints can be filed at https://www.transportation.gov/airconsumer/file-consumer-complaint, or by calling 202-366-2220.