CHARLOTTE, N.C. -- A commuter plane taking off with 21 people crashed into an airport hangar and burst into flames Wednesday, killing everyone on board, authorities said.
The cause of the crash -- the deadliest U.S. air accident in nearly 14 months -- wasn't immediately clear.
US Airways Express Flight 5481, a Beech 1900 twin-engine turboprop, was taking off in clear, windy weather from Charlotte/Douglas International Airport when it hit the corner of the hangar at full throttle just before 9 a.m., officials said.
Benjamin Witkege told The Charlotte Observer that the plane attracted his attention as he and his girlfriend arrived at the airport.
"The plane was climbing too steep," said Witkege, 19, of Roanoke, Va. "I told her, 'It looks like that plane is not doing right.'"
As they stopped to watch, he said, the plane moved into a twisting dive.
Nineteen passengers and two crew members were aboard the flight, which was operated by Air Midwest and headed to Greenville-Spartanburg, S.C., said Federal Aviation Administration spokeswoman Laura Brown.
'A horrible sight'
The plane took off to the south and veered sharply back toward the airport and crashed into a US Airways hangar, airport director Jerry Orr said.
"The plane is so destroyed there's not much to see," said Charlotte police spokesman Keith Bridges. "It's just a horrible sight."
The pilot contacted the tower after takeoff and indicated an emergency, FAA spokesman Greg Martin said. "However, it was cut short and the emergency was never identified," Martin said.
The National Transportation Safety Board sent a team of investigators to the scene. They likely would check into possible engine failure or pilot error, whether ice was on the wings or whether the flaps deployed correctly, said Chuck Eastlake, an aerospace engineering professor at Embry-Riddle Aeronautical University in Daytona Beach, Fla.
"Any airplane that crashes on takeoff, whether it rolled over its back or not, probably is a candidate for engine failure to look at," Eastlake said.
Martin said the plane should have had a flight data recorder and a cockpit voice recorder that could provide some information about why it crashed.
There was no immediate indication of terrorism, the FBI said.
Orr said there were no survivors aboard the plane, but three people on the ground who were thought to have been missing had been accounted for.
At Greenville-Spartanburg airport, a room had been set up for friends and relatives arriving to pick up passengers from the flight, spokeswoman Rosylin Weston said.
The plane was about 8 years old and had 15,000 hours of flight time and 21,000 takeoffs and landings, said Jonathan Ornstein, chief executive of Mesa Airlines, which owns Air Midwest.
A maintenance alert had been issued in August for the same model of airplane after attachment bolts for the vertical stabilizer were found loose on a plane during a scheduled inspection.
According to FAA records, the aircraft the crashed had reported service difficulties 10 times. In November, the company reported a leaking fuel pump, which was replaced. In May, the plane's left main landing gear wouldn't retract as it was taking off; it landed safely and the problem was fixed. Other problems were minor, including a stuck light switch, cracks on a flap and chafing on brackets that attached a flap.
The government's maintenance records did not say whether the plane's vertical stabilizer had been checked after the alert, and the company's records were not immediately available.
"We clearly are deeply concerned about this event, about our crews and our passengers," Ornstein said from the company's headquarters in Phoenix shortly after the crash. "I can only express our greatest sympathy, my personal sympathy, to all those involved."
Mesa Airlines operates in the East and Midwest as US Airways Express, in the West and Midwest as America West Express, in Denver as Frontier JetExpress, in New Mexico as Mesa Airlines and in Kansas City with Midwest Airlines.
The crash came after a year in which there were no deaths aboard a passenger or cargo airliner in the United States. It had been the third time in a decade that a year went by without a fatality on a commercial plane, according to the FAA.
The last U.S. commercial airline crash was American Airlines Flight 587, which went down in New York on November 12, 2001, killing 265 people.