FAA Zeros In on Unsecured Tail Bolts; Risk Is Catastrophic

When two Allegiant Airlines pilots couldn't control their plane and scrubbed a takeoff from Las Vegas in August, the carrier discovered that a critical piece of equipment in the tail had come loose.

Allegiant ordered inspections of its other Boeing Co. MD-80s to ensure that all similar connections were secured. Eight days later, Allegiant said in response to questions from Bloomberg that all its aircraft "were found to be in working order."

By that time, mechanics had already come across two other jets with bolts in similar locations that weren't properly locked in place, according to company repair logs obtained by Bloomberg. Later that month, they discovered another unsecured bolt on a third plane. While Allegiant says the fasteners weren't on the same component that failed in Las Vegas, the U.S. Federal Aviation Administration says it is aware of the findings and has stepped up oversight of the airline.

"The FAA intensified its focus on the carrier's flight operations and aircraft maintenance programs," the agency said Oct. 15 in an e-mailed statement, without elaborating.

The aborted Aug. 17 takeoff occurred after a device that moves one of the jet's two elevators -- panels on the tail used to climb and descend -- was disconnected, according to Allegiant. The maintenance logs from the follow-up checks show that two planes each were found to have an unsecured elevator bolt, while the third jet had an unsecured bolt on another key part - an aileron, which is on the wing and is used in turns.

Allegiant's Response

Because the findings on the three other planes didn't specifically involve the so-called elevator boost actuator at issue in Las Vegas, they weren't considered part of the inspection results, Allegiant spokeswoman Kimberly Schaefer said last week in response to questions from Bloomberg about the maintenance logs.

"During the fleet-wide inspection of the elevator boost actuators, Allegiant mechanics made additional repairs to other aircraft, as they do each and every day," Schaefer said by e-mail. "As these repairs were outside the scope of the fleet campaign in question, they were logged per normal procedure."

FAA rules require the reporting of all maintenance actions -- including fixing mistakes such as poorly attached bolts -- but they don't have to be disclosed immediately. Those actions are entered into a database shared quarterly with the agency.

"Catastrophic Results"

John Goglia, a former member of the U.S. National Transportation Safety Board, said the multiple instances of unsecured bolts and their locations on the aircraft were so serious they "should result in a focused FAA audit."

"This is not a coffee maker that we're talking about here," Goglia said in a telephone interview. "This is a primary flight control on the airplane. Anything less than perfect work on this system can have catastrophic results."

Allegiant, a unit of Allegiant Travel Co., specializes in flights to vacation destinations centered on Las Vegas and Orlando, Florida. Flight 436 on Aug. 17 was supposed to fly to Peoria, Illinois, from Las Vegas, carrying 158 passengers and six crew members.

Takeoff Halted

As the MD-80 rumbled down a Las Vegas runway, the front of the plane began to rise off the ground prematurely, defying the pilots' attempts to keep the nose down, according to an FAA report. They abruptly halted the takeoff roll at 138 miles (222 kilometers) per hour, according to the report.

Allegiant's inspections of its MD-80s found two other planes with elevator bolts that weren't properly connected, the maintenance records show. On Aug. 27, a mechanic working on another MD-80 discovered an unsecured bolt on an aileron, a maintenance log shows.

Those assemblies are considered so crucial that mechanics are supposed to insert pins to ensure the nuts used to fasten the bolts can't come undone.

"Any failure to properly secure any part of a flight control is a major problem," said Goglia, the ex-NTSB member who is also a former aircraft mechanic. "More than one occurrence clearly indicates a maintenance organization that is not functioning properly."

Allegiant's Maintenance

Allegiant responded: "While we respect the credentials of Mr. Goglia, he does not have any specific knowledge about our company or the details of our operation."

AAR Corp.'s AAR Aircraft Services does large-scale maintenance on Allegiant's MD-80s in Oklahoma City. Mechanics from Allegiant and AAR work on the areas of the aircraft where the wrongly secured bolts were found, Schaefer said.

"Since hearing of the August 17 incident, AAR has been working with Allegiant and the FAA to investigate," AAR spokeswoman Kathleen Cantillon said by e-mail. "AAR has a 60-year history and culture of safety and compliance."

Work on flight control systems is considered critical because errors can lead to accidents, Goglia said. The NTSB concluded that an improperly installed elevator bolt caused an Emery Worldwide Inc. cargo jet in California to lose control and slam into the ground in California in 2000, killing all three people on board.

The FAA said its intensified focus on Allegiant was also prompted by a separate July incident in Fargo, North Dakota, in which a pilot reported a low-fuel emergency. Allegiant said it's working with the FAA in examining that episode.

Earlier this year, the FAA put Allegiant under heightened surveillance as pilots neared a potential strike, a step the agency sometimes takes during possible labor actions or when a carrier is struggling financially. Allegiant won a court order in April blocking the walkout, and in May said the FAA had ended the additional scrutiny.