The volume of customer complaints against U.S. airlines is so high this year that the Department of Transportation reportedly cannot keep up with them for the first time ever.

Airline records related to flight delays and cancellations, lost luggage and damaged wheelchairs — the most common consumer qualms — have worsened since last year, an analysis of federal flight operations data by the U.S. Public Interest Group (PIRG) shows.

"It's not your imagination, air travel has become much more stressful. We have new fees, more cancellations, delays, long TSA lines and lost bags," Teresa Murray of the PIRG told CBS MoneyWatch.

The group analyzed airline operations data from the U.S. Department of Transportation for the month of June alone as well as for 2023.

"It hasn't gotten any better than last year — and last year was awful," Murray added. "The DOT is trying to figure out a new way to keep up with complaints." 

Consumer complaints in 2022 hit 78,000, an increase from roughly 50,000 in 2021 and five times more than the number of complaints filed in 2019. The record is 102,550 complaints filed in 2020.

As a result of the overwhelming volume, the DOT hasn't released any complaint totals for 2023 beyond February data. 

The DOT did not immediately respond to CBS MoneyWatch's request for comment. A DOT official did tell U.S. PIRG that the agency doesn't expect complaints to return to lower pre-pandemic levels.

The U.S. PIRG report, "The Plane Truth Part 3," comes as the holiday travel season approaches and people gearing up for trips hope for the best but brace themselves for the worst.

Long tarmac delays and more

In June, when the summer travel season kicked off, airlines had 74 tarmac delays that exceeded three hours on domestic flights, up from 60 delays in June 2022. 

Only 71% of flights arrived on time, compared to May's 81%. Two percent of domestic flights were cancelled, up from 0.6% in May, according to PIRG's analysis. There was also an uptick in mishandled bags and damaged wheelchairs or scooters. 

Best and worst airlines

Frontier Airlines, Spirit Airlines and JetBlue Airways had the worst records for on-time performance in June. Alaska Airlines, Delta Air Lines and Hawaiian Airlines had the best on-time performance.

Spirit, American and United had the worst records when it came to mishandling customers' baggage for the first half of 2023.

No matter what airline you fly, there's no guarantee you'll arrive on time with your luggage, wheelchair and sanity intact. However, there are steps fliers can take to mitigate the risks of an airline trip going awry.

"There are a lot of things people planning to travel for the holidays can do," Murray said. 

1. Know your flier rights

"Don't wait until after you have a problem, or your flight is canceled, or your bag lost to say, 'Now what? What are my rights?'" said Murray. "Skim through contracts of carriage so if there is a problem, you can be proactive and you don't just get run over." 

2. Plan to arrive a day early

"We recommend that if people have an important event like a wedding or cruise they have to make, to go the day before. Way too often, flights get canceled or delayed and if you miss half of a connecting flight, you won't get there," Murray said. 

3. Use a credit card to book

Credit cards offer consumers far greater protection when they dispute charges. Oftentimes, a credit issuer will give you a refund while they work to recoup funds on your behalf.

4. Take the first flight of the day

"Planning ahead is a big thing. We recommend flying early in the morning if you can and taking the first flight out of the day," Murray said. 

If you're on the first flight of the day, cascading effects of delays and cancellations are less likely to affect you.

5. Try to fly non-stop

Taking two flights effectively doubles the chances of a flight-related mishap. And of course, if the first leg is delayed, you could miss the connecting flight.

6. Don't check a bag, use a carry-on

If you have your eyes on your luggage the whole time, the airline can't lose it.

"If you can avoid checking, that's one thing you're taking out of the equation that could go wrong," Murray said.

Use an Apple AirTag or similar device to track bags that must be checked.

"I heard from so many people last holiday season who said the airline had no idea where their bag was, but they could see what city it was in," Murray said. "They called up the airline and said this is where my bag is. To extent that consumers can take control of the situation, they will be much better off."

7. Download your airline's app

The fastest way to rebook in the event of a delay or cancellation is often through an airline's app, versus waiting on long lines at airports' customer service desks or help lines. 

"Last December and January, especially over the Christmas meltdown when flights were getting delayed and canceled, people were waiting hours and hours on hold, trying to calls into customer service. If you have the app on your phone, you can get a lot done, a lot more quickly rather than rotting on hold."