Check your flight status: Southwest Airlines may cancel 300 additional flights on Sunday, having already canceled the same number of departures Saturday. The move, while necessary based on safety fears, will cost the carrier millions. The airline immediately grounded 79 planes from its Boeing 737 fleet after one with a three-foot-long hole in its fuselage was forced to make an emergency landing on Friday. Some 118 passengers and five crew members on a flight from Phoenix to Sacramento landed safely in Yuma, Arizona, though at least two on board were treated for minor injuries. “There was a hole in the fuselage about three feet long. You could see the insulation and the wiring,” a woman identified as Cindy told a local CBS television affiliate in Sacramento.