Flights at SFO canceled, delayed amid nationwide FAA ground stop

• The Federal Aviation Administration said Friday that it is "closely monitoring a technical issue impacting IT systems at U.S. airlines" and that several airlines had requested "assistance with ground stops for their fleets."
• George Kurtz, president and CEO of CrowdStrike, said in a post to X the company was "actively working with customers impacted by a defect found in a single content update for Windows hosts."

Driving the news: American, Delta, United and Allegiant Airlines grounded flights early Friday morning due to communications issues, per an FAA alert.

Zoom in: The outage hit United Airlines hard at SFO, where no United flights left the airport for several hours Friday morning, the San Francisco Chronicle reports.

• As of 9:17am, 122 flights going to or from SFO had been delayed and 81 had been canceled, according to FlightAware.

• At 7am, SFO said on X its systems were functioning and that airline systems were coming back online. It said to check with airlines for flight status updates.

Zoom out: San Francisco's 911 dispatch system was unaffected, but fire officials believe the bug "most likely" caused about 20 false fire alarms to set off around 2:30am throughout the city, the San Francisco Standard reports.