OAKLAND (CBS SF) – Eleven flights have been cancelled out of the Bay Area on Wednesday after Southwest Airlines decided to ground 128 planes when they failed to inspect backup hydraulic systems used to control the rudder if the main system fails.

Airport officials said nine flights have been cancelled out of Oakland International Airport, along with one arriving flight.  At San Francisco International Airport, two flights have been cancelled.  Officials at Mineta San Jose International said there have been no cancellations out of their airport.

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A passenger at Oakland was all ready to head to Southern California when she heard the bad news about her Southwest flight.

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“We just arrived at the airport and it was cancelled.  We were going to Anaheim to go to Disneyland,” said the stranded mother.  “It was my daughter’s birthday and I’m pretty upset about this.  Because now we just have to wait and see if we get on the next flight.”

Airport officials are advising passengers to check with Southwest before leaving for the airport to make sure their flights have not been cancelled.

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Southwest notified the Federal Aviation Administration after discovering the problem.  Late Tuesday night, the FAA agreed to let the airline resume flying the planes while inspections are done over the next few days.

Dallas-based Southwest is the nation’s fourth-biggest airline. It has 665 jets, all of which are some version of the Boeing 737, including nearly 450 of the 737-700. That model seats 137 or 143 passengers, depending on the layout.

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