LOS ANGELES (Reuters) – Southwest Airlines said it expects to cancel 300 flights on Saturday to allow inspections of 79 aircraft from its Boeing 737 fleet, after one of its planes with a gaping hole in the fuselage made an emergency landing.

Passengers aboard Southwest Flight 812 from Phoenix to Sacramento on Friday heard a loud noise and the hole appeared suddenly at about mid cabin. As a result, the pilot landed at a military base in Yuma, Arizona.

Southwest and Boeing engineers will inspect the grounded aircraft, and the airline is working with federal authorities to determine the cause of the incident, Southwest said in a statement.

The emergency aboard the Boeing 737-300 prompted the airline to examine other similar aircraft within its fleet, with a total of 79 inspections planned at five locations. Earlier on Saturday, Southwest said 81 aircraft would be grounded for inspections.

Because of the inspections, which will occur over the next several days, Southwest said it expects to cancel about 300 flights on Saturday.

A total of 931 Boeing 737-300s are operated by all airlines worldwide, with 288 of them in the United States, the Federal Aviation Administration said.

The Southwest flight that was forced to make an emergency landing had 118 passengers and five crew members on board.

The pilot made a rapid descent from about 34,400 feet to 11,000 feet, in accordance with standard practice, the FAA said. The purpose was to reach an altitude where supplemental oxygen is no longer required.

One flight attendant and at least one passenger were treated at the scene for minor injuries, Southwest said.

The Boeing 737 landed at 4:07 p.m. local time after declaring an emergency, said Ian Gregor, an FAA spokesman.

After the passengers deplaned at the Yuma Marine Corps Air Station, the airline arranged for another aircraft to take them to Sacramento, the company said.

Passengers described the harrowing scene to the CBS television affiliate in Sacramento, detailing the damage to the plane.

"They had just taken drink orders when I heard a huge sound and oxygen masks came down and we started making a rapid descent. They said we'd be making an emergency landing," a woman identified as Cindy told the station.

"There was a hole in the fuselage about three feet long. You could see the insulation and the wiring. You could see a tear the length of one of the ceiling panels."

Another passenger tweeted that she was "happy to be alive."

"Still feel sick. 6 foot hole in the skin of the plane five rows behind me. Unbelievable," Shawna Malvini Redden wrote. She said she texted her husband while in the air, saying "I love you."

(Additional reporting by David Schwartz and Lauren Keiper in Boston; Editing by Greg McCune)

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