SFO --A United Airlines network outage struck airports nationwide Tuesday, stranding travelers flying out of San Francisco International Airport for hours, an airport spokesman said.
The outage affected all of United's airport operations, as well as its website, United.com, which was down for nearly two hours Tuesday afternoon.
United flights to its hub in Newark, N.J. were scheduled to be held at their origin until 6 p.m. Eastern, The Associated Press reported. Flights to United's San Francisco hub were also held at their destination.
All computer operations were restored about 2:50 p.m., although residual impacts continued to strand passengers at SFO, said airport spokesman Mike McCarron said.
"Our biggest problem at this point is that we have a very congested lobby," McCarron said. "We've opened every possible checkpoint, but it's going to take a couple hours to clear up. It's going to be a very slow afternoon."
McCarron said a prolonged delay in United flights leaving the airport could create a major backup of arriving and departing flights.
"We just have concerns about getting people on the planes so that planes going out get out, and planes coming in get in," McCarron said.
The airline says it is trying to minimize any impact to its operations.
Flights to and from Oakland International Airport, which is not served by United, were not affected.
United Continental Holdings
"United Airlines have (sic) a 'global' computer outage," one passenger's tweet said. "Writing all bag tags and boarding passes by hand. This will be 'fun.'"
The Associated Press contributed to this report. Contact Erin Ivie at 925-847-2122. Follow her at Twitter.com/erin_ivie.