The same month that a viral video depicted a United Airlines passenger being dragged from his seat, complaints against airlines in the U.S. soared 70%.

A U.S. Department of Transportation report Wednesday showed that 1,909 complaints were filed in April against airlines flying in the U.S., up from 1,123 complaints in the same month last year.

Although flight delays and cancellations increased somewhat in April, the most likely cause of the complaint surge was the public reaction to the bloody incident April 9 that put a focus on the treatment of passengers by the nation’s airlines.

David Dao, a passenger on a flight from Chicago to Louisville, Ky., was dragged from a seat and down the airplane aisle by airport security officers after refusing to give up the seat, which United wanted for an airline crew member. Dao suffered a broken nose, a concussion and lost two teeth in the incident.


United and Dao’s attorneys reached a settlement over the incident but both sides declined to disclose the terms.

Paul Hudson, founder of the passenger rights group Flyersrights.org, said the Dao incident may have emboldened passengers to speak out about how airlines are treating them.

“A lot of people have realized that things are bad and that they can complain about it,” said Hudson, whose group has more than 60,000 members.

The biggest number of complaints filed in April were against American Airlines (324), followed by Delta Air Lines (297) and United (265), the federal report said. Low-cost carrier Spirit Airline had the highest rate of complaints, 7.2 complaints for every 100,000 passengers, compared with 3.04 complaints for every 100,000 passengers for United Airlines.


Most complaints were about flight problems such as cancellations and delays. Those complaints more than doubled in April, to 753 from 372 the year-earlier period, the federal agency said. Complaints about overbooking also more than doubled, to 89 from 42 in April 2016.

In April, 78.5% of all flights by U.S. carriers arrived on time, down from the 84.5% on-time rate a year earlier. The rate of canceled flights rose to 1.6% of all scheduled domestic flights from the 0.9% cancellation rate posted in April 2016, according to the agency.

hugo.martin@latimes.com

To read more about the travel and tourism industries, follow @hugomartin on Twitter.