For a week and counting, flying in and out of Newark Airport has inflicted misery on travelers. The cancellations and  delays have been caused by a cascade of infrastructure failures and staffing

The ground delay, which is separate from the outage, is related to "low ceilings" for departures, tied to poor weather conditions.

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.