United Airlines is facing a financial hit and potential long-term reputational harm as flight delays and cancellations pile up due to ongoing disruptions at Newark airport - one of its largest hubs and among the busiest in the country.

U.S. Transportation Secretary Sean Duffy announced plans to scale back flights at Newark for "the next several weeks" as New Jersey's largest airport grapples with a chaotic combination of radar outages, persistent delays and a critical shortage of air traffic controllers.

Moving air traffic controllers means retraining them on the quirks of a new facility, and the process can take years.