United said Thursday that FAA technology outages, runway construction and high winds led to the disruptions, which forced it to divert at least 21 flights. Newark is one of the most congested airports in the country, and Kirby has repeatedly complained about shortfalls of air traffic controllers. United has also trimmed its Newark schedule in recent years because of excessive delays, blaming similar factors. The Transportation Department on Thursday offered a new slate of incentives to help alleviate staffing shortages of air traffic controllers, a problem that has persisted for years and worsened during training pauses amid the Covid-19 pandemic. United Airlines said it would waive change fees or fare differences for customers affected by the Newark disruptions.

United Airlines will cancel 35 roundtrip flights a day from its schedule at Newark Liberty International Airport in New Jersey after thousands of passengers faced hourslong delays this week, CEO Scott Kirby said Friday, blaming the disruptions on air traffic controller staffing shortages and the Federal Aviation Administration's technology problems.

Delays and cancellations are piling up again Friday at Newark Liberty International Airport (EWR) in Newark, New Jersey, due to air traffic control staffing shortages and construction on one of three runways. As of Friday, more than 200 flights were delayed at Newark and around 20 were canceled, according to the flight-tracking website FlightAware. The airport also is "currently experiencing inbound flights delayed at their origin an average of 1 hours 32 minutes," it added. Over 500 flights in and out of Newark were delayed on Thursday, and more than 200 flights were canceled.