Alaska Air Group has canceled nearly 600 flights since Friday's FAA ground stop

Alaska Air Group has canceled nearly 600 flights since a nationwide Federal Aviation Administration ground stop began Friday, affecting the travel plans of more than 52,000 guests, the company said in a Saturday morning update. That is up from the more than 200 cancellations the airline reported Friday evening, shortly after the order was lifted.

The cancellations, along with diversions, left many Alaska Airlines and Hawaiian Airlines aircraft and crews out of position, the company said. "It will take time for our operations to get back on track through the weekend," the airline said in its statement.

The company has a flexible travel policy in place for guests who need to change plans. It advises travelers to check flight status at alaskaair.com, hawaiianairlines.com or its mobile app before heading to the airport.

A ground stop holds departing flights at their origin airports, while aircraft already in the air continue to their destinations. This one covered all airlines. The FAA lifted it around 5:30 pm Pacific Friday, after more than four hours, the airline said.

For Alaska travelers, the halt fell on flights leaving the state. Flights within Alaska were not affected, according to the airline. Juneau International Airport Manager Andres Delgado told departing travelers to expect delays on flights leaving Alaska, while flights within the state were expected to depart. In Hawaii, flights between the islands, flights from the West Coast to Hawaii and international departures from Honolulu were also allowed to continue.

"On November 13 at approximately 3:30 p.m. ET, the FAA experienced a technical problem that resulted in issuing a nationwide ground stop," the agency said on a questions-and-answers page posted Sunday.

The FAA said data flooded one of its networks at a rate of 1,000 connection attempts every four to five seconds until its older equipment became unstable. That instability began at 17 of its 22 Air Route Traffic Control Centers, the regional centers that handle aircraft between airports, and spread into several approach control facilities. The agency said that based on all available evidence, it had no indication the outage was a cyberattack.

A City and Borough of Juneau notice Friday attributed the order to communication issues affecting those regional centers and said the FAA ordered departing traffic to stay on the ground for safety.