(CNN) -- Issues with its planes' emergency exit slides prompted Allegiant Air to put most of its fleet out of service Friday, wreaking havoc with its flight schedule as the carrier rushed to shuffle passengers and gets its aircraft in compliance.
In a press release, Allegiant explained that a "compliance issue" on its MD-80 planes prompted it to order the "immediate inspection and overhaul" of most of its emergency slides.
That left all 52 of Allegiant's MD-80 planes out of service at one point, though by late afternoon 18 of those aircraft plus its six Boeing 757 jetliners and three Airbus A319s were operational.
This forced Allegiant to juggle its schedule, pushing back 16 flights to Saturday, canceling two altogether and causing various delays, according to airline spokesman Brian Davis. After all this,103 of Allegiant's 121 flights Friday eventually headed to their destinations.
The headaches began Monday, when smoke detectors went off on an Allegiant flight destined for Peoria, Illinois, as it was taxiing from the terminal to the runway at Las Vegas' McCarran International Airport. The pilot decided to evacuate the 144 passengers and six crew members using the aircraft's emergency exit slides -- something that they did successfully, said Davis.
When reviewing this incident, Allegiant officials noticed a discrepancy between its practice of overhauling its MD-80 slides every three years with the manufacturer and Boeing's recommendations -- which Allegiant views as requirements -- that it happen every year.
"That meant we were not in compliance, so we took every aircraft out of service," Davis said, insisting there was never an indication any slides were unsafe or not working properly.
This process began overnight Thursday. Initial checks revealed that 14 of the company's MD-80s were compliant (because they had gotten new slides, four for each plane, within the past year) and could fly, according to Davis.
By Saturday -- typically a light day for Allegiant, which caters largely to leisure travelers going to and from mid- and small-sized airports to vacation destinations like Florida, California, Arizona and Hawaii -- 22 MD-80s should be operational.
"Our best guess is that ... by the end of the month, everything will be back to normal," said Davis. "But passengers will not see disruptions sooner than that, hopefully."
In fact, the airline spokesman says all flights should head off fine Saturday, as Allegiant uses its full available fleet as well as aircraft contracted from other carriers.
But that may not be the case Sunday and Monday, two of the airlines' busiest days of the week. Any passengers affected then or on any other day by the issue (including Friday) will get compensated with anything from a $100 voucher for delays under four hours to a refund and $200 voucher for those on rescheduled flights.
CNN's Travis Sattiewhite contributed to this report.