The Federal Aviation Administration is working on a short-term fix to the problems at the Newark airport that includes technical repairs and cutting flights to keep traffic manageable while dealing with a shortage of controllers.

In a letter to customers sent Friday, United CEO Scott Kirby said the Federal Aviation Administration’s longstanding staffing problems finally "boiled over" this week, as technological problems caused dozens of diverted flights, and hundreds of canceled and delayed ones. Kirby said 20% of the air traffic controllers walked off the job as well.