US flights resuming after FAA alert system outage causes disruption

Thousands of flights delayed because of problem with system that alerts pilots about hazards or changes at airports

Domestic flights across the US were temporarily grounded on Wednesday morning, after an IT failure in a critical aviation safety system.

The Federal Aviation Administration (FAA) said that the system that alerts pilots and airlines about any hazards was not functioning. The breakdown led to more than 4,600 flights being delayed within, into, or out of the US, the flight tracking website FlightAware showed. It was not immediately clear if the outage was a factor.