It was a mechanical failure of an Allegiant Air jet at one of a flight's most-vulnerable moments — takeoff.
Allegiant Flight 436 bound for Illinois was in its takeoff roll on Aug. 17 in Las Vegas traveling 138 mph when the nose of the aircraft prematurely rose from the runway. The pilot pushed the yoke, or control column, fully forward, yet the nose continued to rise.
But the pilot apparently cut back on power to safely abort the takeoff and return to the gate. No injuries were reported.
That incident, detailed in an Allegiant report to the Federal Aviation Administration, is perhaps the most serious to date for the budget airline during a turbulent summer for the Las Vegas-based carrier.
Three Allegiant flights made emergency landings at St. Pete-Clearwater International Airport in June and July. Another flight from the airport to Virginia had to make an emergency landing after passengers reported hearing an engine pop. Allegiant also had an embarrassing episode when a pilot flying into Fargo, N.D., requested an emergency landing because he was low on fuel.
The airline is a key cog in the Pinellas tourism industry and accounts for about 95 percent of the traffic at St. Pete-Clearwater.
The FAA said it is investigating the latest incident in Las Vegas, which aviation experts said was both rare and potentially disastrous.
Allegiant said the malfunction was caused by an aircraft elevator found on the tail of the aircraft. A device that moves one of the plane's two elevators had disconnected, Allegiant said. The FAA said the component had actually "fallen off," which jammed the elevator in one position.
The flight at Las Vegas' McCarran International Airport with 158 passengers and six crew members was bound for Peoria, Ill.
John Cox, a St. Petersburg resident who is a former U.S. Airways pilot and a former safety official at the Air Line Pilots Association, said an elevator failure is exceptionally rare. A failure in a flight, he said, could lead to difficulty controlling the aircraft.
"I've never seen it nor do I know of anyone who has ever seen it to that level of severity," Cox said of an elevator malfunction. "It would scare me to have one do that. I think the crew reacted well to an unexpected event. If the plane had gotten airborne, it could have been hard to control."
Cox said a critical flight control like the elevators are essentially designed never to fail. In fact, he said, an elevator malfunction such as this one isn't even tested in flight simulators during pilot training given its rarity.
The aircraft was a McDonnell Douglas MD-83 that was manufactured in 1991. The MD-80 series aircraft is the workhorse of the Allegiant fleet. MD-80s compose 48 of the airline's 76 aircraft, according to airfleets.net.
"Immediately following the event, Allegiant initiated a fleet-wide inspection of all of its MD80 aircraft to ensure the flight control systems in those aircraft were functioning properly before returning them into service," Allegiant said in a written statement. "All aircraft were found to be in working order."
A spokeswoman for Allegiant declined to characterize the severity of the incident.
"We continue to cooperate with (the FAA) to review all of the information related to the event," the airline said. "The continued safety of our passengers and crew is always our top priority."
John Goglia, a former airline mechanic who served on the National Transportation Safety Board, told Bloomberg News that Flight 436 could have ended disastrously.
"This is a very big deal," Goglia said. "At very minimum, they would have had control problems. In a worst-case scenario, they would have been unable to control it. It could have been a disaster."
Cox noted that after a repair of any flight control system, a second qualified mechanic is required to inspect the repair to certify that it was done properly.
As a low-cost airline targeting tourists in smaller, underserved cities, Allegiant has boosted passenger numbers at St. Pete-Clearwater to recent highs.
The Pinellas County airport saw 173,743 passengers during July, which is the highest number in airport history and a 50 percent increase over July 2014, according to airport officials. St. Pete-Clearwater has seen a 31 percent bump in traffic during the first seven months of this year — domestic traffic is up 31 percent and international traffic is up by 22 percent.
Allegiant added three new flights to and from St. Pete-Clearwater in May — Tulsa, Okla.; Akron, Ohio; and Durham, N.C. The carrier is adding a flight to and from Memphis beginning Oct. 1, bringing the total of nonstop service from St. Pete-Clearwater to 44 cities.
Contact William R. Levesque at firstname.lastname@example.org or (813) 226-3432. Follow @Times_Levesque.