Are maintenance problems at Allegiant Air the result of an airline growing too fast?

David Stuckenberg has flown thousands of hours as an Air Force pilot and a passenger on commercial airliners. He said a flight on Allegiant Air last month was his worst flying experience ever.

The takeoff from St. Pete-Clearwater International Airport aborted at high speed, announced by a loud boom from a failing engine. It took more than three hours for Allegiant to find a replacement plane. Airline employees provided little information to passengers, who did not know if they would take off again in five minutes or five hours. A 90-minute wait on a customer service phone line ended when an employee hung up on him.

"It was pretty apparent most of the staff is very inexperienced, and they just don't really know what they're doing," said Stuckenberg, 35, who lives in Tampa. "The customer service was atrocious. That was our last Allegiant flight."

Some airline safety advocates question whether Allegiant, a budget carrier that flew more than 1.4 million passengers at the Pinellas airport last year, is showing signs of stress caused by its rapid growth, possibly creating a dangerous situation in which it can't keep up with maintenance.

They draw a parallel between Allegiant and ValuJet, the upstart airline whose gaudy expansion troubled the FAA in the months leading to the 1996 Everglades crash that killed 110 people.

Such comparisons may be particularly uncomfortable for Allegiant, whose CEO, Maurice Gallagher Jr., was ValuJet's cofounder.

"It appears Allegiant is following the same recipe for disaster ValuJet followed," said Mary Schiavo, a former U.S. Department of Transportation inspector general who questioned ValuJet safety and wrote a book on aviation safety, Flying Blind, Flying Safe. "The airline is designed as a cash cow. The things that passengers are seeing are indicative of the overall condition of the airline. They're clues. And they're valued clues."

The last year has proven to be one of Allegiant's most challenging with a string of emergency landings, aborted takeoffs and delayed flights. In the last week of December alone, five Florida flights were forced to make unscheduled landings because of mechanical problems.

Allegiant executives would not comment for this story. They have steadfastly maintained their airline is among the safest and the company hasn't had a crash in nearly 20 years of operation. They have accused their pilots' union, with whom they are engaged in bitter contract negotiations, of using the media to drum up concern about the airline's safety.

Allegiant executives do acknowledge growing pains at an airline consistently ranked as one of the fastest expanding in the industry. Said chief operating officer Jude Bricker in January: "Operational challenges that we had over the last several months really had to do mainly with the growth that we were putting through our network ...''

Rapid growth drives Allegiant's best-in-the-industry profit margins, leading Schiavo to conclude that for the airline, "It's all about fast money.''