Flight delays and cancellations on U.S. airlines rose in September, with some of the disruption caused by a fire that shut down an air traffic control centre near Chicago.

The U.S. Department of Transportation said Thursday that flights on the nation’s largest airlines arrived on time 81.1 per cent of the time, down from 83.8 per cent in September 2013.

The 14 airlines covered in the government report cancelled 1.4 per cent of their U.S. flights in September, up from 0.9 per cent a year earlier.

Airlines for America, a trade group of the largest carriers, said that about 4,500 September flights were cancelled because of the fire. That would be two-thirds of all the cancellations for the month and more than the total for September 2013. Flight-tracking service FlightAware.com said that just over 4,000 Chicago flights were cancelled and more than 5,000 delayed during the last few days of the month after the fire.

It took two weeks for the Federal Aviation Administration to gradually restore normal loads at Chicago’s airports – O’Hare, a hub for United and American, and Midway, Southwest’s biggest operation.

Hawaiian Airlines held its usual place on top of the on-time ratings. Delta finished best among the biggest five carriers. Envoy Air, the regional arm of American Airlines, had the worst record, followed by ExpressJet, which operates regional flights for United, American and Delta.

Envoy and ExpressJet also finished last in the rate of bags that were lost, stolen or damaged.

Consumers filed 1,157 complaints about air service in September, up 14 per cent from a year earlier. Very few customers bother to file complaints with the government, however – there are about 2 million passengers a day on U.S. airlines.

ExpressJet had the highest rate of complaints; Virgin America the lowest.