CLEARWATER (FOX 13) - Federal airline investigators have begun a review of Allegiant Air's operations two years before it was scheduled after several high-profile maintenance scares last summer.
The FAA conducts the reviews of major airlines every five years, but can begin them early if needed.
The program is known as the National Certificate Holder Evaluation Process, and is a measure by which the FAA can determine if an airline is operating within safety regulations.
John Goglia, aeronautics professor and former National Transportation Safety Board Member, told FOX 13 News the early review represents a significant step by the FAA.
"For the FAA to move up one of their five year reviews of an air carrier is quite unusual, so it signifies that the FAA has got some very serious concerns about that particular operation," said Goglia.
Investigators said the review began in April and will likely be complete by late June. It comes after a series of highly-publicized maintenance events which diverted or forced flights to make emergency landings.
Two incidents were specifically cited as concerns leading to the early investigation.
In July, a flight piloted by Allegiant executives was forced to make an emergency landing at a closed airport in Fargo, N.D. after running dangerously low on fuel.
A month later, a plane safely aborted takeoff in Las Vegas, when a component called an elevator got stuck and caused the plane's nose to lift off the ground before it was supposed to. Experts say that could have ended in disaster.
Allegiant operates 95-percent of the flights at St. Pete-Clearwater International Airport and is responsible for a surge in tourism in Pinellas County.
Despite the maintenance mishaps, Allegiant's passengers remain loyal.
In financial records recently released, the company posted an 11-percent increase in profit for $72 million in the first quarter of 2016, compared to the same time period in 2015.
More passengers were flying, as well. This year, Allegiant flew 2.6 million passengers, nearly 15-percent more than in the first quarter last year.
Allegiant refused to characterize the importance of the early review. In a statement to FOX 13 News, an airline spokesman said, "Allegiant is currently undergoing... a routine inspection performed by the FAA. We are confident in our operations, and we welcome the routine oversight."