SEATTLE (CBS/AP) — A National Transportation Safety Board report blames shoddy workmanship for a tear in the roof of a Southwest Airlines flight in 2011.

The Boeing 737-300 was en route from Phoenix to Sacramento, when a 5-foot-long gash opened in the fuselage. Air rushed in, oxygen masks dropped from the ceiling and a flight attendant fainted, breaking his nose, as the pilots made a rapid descent and an emergency landing at Yuma International Airport.

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The NTSB’s findings released Friday said that when the jet was assembled 15 years earlier, two panels appeared to have been misaligned, and many rivet holes were drilled incorrectly. The agency called it “extremely poor manufacturing technique.”

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It isn’t clear whether the work was done at initial fuselage assembly at Boeing’s plant in Wichita, Kansas, or during final assembly in Renton, Washington Subsequent inspections of other 737s found no similar damage.

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