Oxygen masks used on Southwest flight after cabin loses pressure DALLAS A Southwest Airlines flight lost cabin pressure midflight, giving passengers and crew a scare and requiring them to wear oxygen masks until the plane was safe. Southwest Airlines confirmed Flight 3201 was en route from Kansas City to Dallas. Passengers and crew were instructed to wear the masks until the plane reached a lower altitude. Spokeswoman Whitney Eichinger says no one was hurt and Flight 3201 landed safely at Love Field on Saturday evening. Eichinger said Monday that the plane lost pressure at about 35,000 feet. She says the pilot followed protocol, descended and deployed the masks. The masks were not needed once the plane was below 10,000 feet. Passenger David Wilding told WFAA-TV that the jet suddenly started to steeply dive. He says they wore the masks for about 20 minutes. A video he shot of the ordeal showed that no one on the plane panicked. Crew did an amazing job! Wilding told WFAA. The plane was carrying 124 passengers and five crewmembers. Eichinger says the jet underwent maintenance Sunday and returned to service Monday.