CHICAGO (CBS) – Dozens of Southwest Airlines planes remained grounded Saturday after a close call on a flight Friday night from Phoenix to Sacramento, Calif.

About 35 minutes into the Southwest Flight 812, passengers heard a loud pop and then the cabin began losing pressure as the fuselage started to rip apart, exposing the sky.

As pressure escaped the cabin, oxygen masks fell. At least one crew member and a fellow passenger fainted, one witness aboard the plane said.

Despite the loss of cabin pressure, the pilots were able make a safe emergency landing in Yuma, Ariz. No serious injuries were reported among the 118 people aboard. The NTSB investigators were examining the plane Saturday.

Transportation expert and DePaul University professor Joe Schwieterman says it will likely be a long investigation.

“This was a close call, but Southwest has had a couple of these. This is a major issue,” Schwieterman told CBS 2’s Mai Martinez at Midway Airport, where Southwest has a major presence.

“It’s a 15-year-old airplane. There’s a lot of stress issues. More maintenance, more routine checking is clearly in order here,” he added.

As a precaution, Southwest grounded 79 of its Boeing 737’s pending inspections. According to the airline, the move caused about 300 flight cancellations and delays of up to two hours on some fights across the country, including here in Chicago where most passengers took the news in stride.

Checking in for his Birmingham, Ala.-bound flight for the third time following two cancellations, Jim Slay said he had no concerns about flying.

“You know I would rather be delayed and have to take later flights knowing that safety comes first,” Slay said.

In the baggage-claim area, arriving passenger, Gail Postulka was just happy to finally reach her final destination.

“Here we are in Chicago safe and sound. Five hours later, but we’re here safe and that is all that matters,” she said.

But others say knowing a plane ripped open mid-flight is terrifying.

“It’s scary. It’s a fear you always have when you fly, but you don’t think about it until something like this,” said Douglas Thorne, who only learned about what happened on Flight 812 as he was checking in for his own Southwest flight.

Southwest says the grounded airplanes will be inspected over the course of the next several days at five locations. The airline also says it is working aggressively to minimize the impact to travel schedules.