A twin-engine seaplane lost one of its wings before it crashed off Miami Beach into the city's main shipping channel killing at least 19 people on board, a US federal safety official said on Tuesday.
Mark Rosenker, acting chairman of the National Transportation Safety Board, told a news conference the breaking apart of the aircraft could be seen in video footage of the Grumman G-73T Turbine Mallard, filmed in its final moments on Monday above water.
"What I've seen is a separation of a wing from the aircraft and, as a result, the aircraft crashing. I can't tell you why," Rosenker said.
"Corrosion could be some of it," he said of the loss of the wing, which split from the aircraft along with one of its turbo-prop engines.
"Fatigue could be some of it," Rosenker added. "A number of issues: stress on the aircraft; inappropriate operation of the aircraft. A number of things could tear the wing off of an aircraft."
A report on Miami's UPN 33 television news said that previously unseen amateur video footage had provided investigators with valuable, last-minute insight into potential causes of the crash.
Earlier, a widely distributed home video showed part of the 58-year-old plane spiraling downward and belching thick black smoke as the rest of the aircraft plowed into the sea in the background.
Rosenker told reporters federal authorities had secured all maintenance and flight records from Ft. Lauderdale-based Chalk's Ocean Airways, the operator of the aircraft, and that the delicate task of raising the fuselage from the seabed would probably be completed on Wednesday.
Rosenker said the doomed plane had been retro-fitted in the mid-1980s and had new engines. Speedy retrieval of its cockpit voice recorder, by FBI and Miami-Dade Police divers, was impossible due to the mangled condition of the underwater wreckage, he said.
Captain James Maes of the US Coast Guard said authorities had been unable to account for one of the 20 people believed to be on aboard the aircraft. They included two crew members and three infants.
The plane was on its way to the Bahamian island of Bimini, 80 km away, carrying Bahamians who had traveled to Miami for Christmas shopping.
Chalk's has operated between Miami and the Bahamas since 1919, when Prohibition was in full force and rum-running from the Bahamas provided a steady income, Chalk's said on its web site.
The airline said it had never suffered an accident involving passengers before, but one of its aircraft crashed on takeoff from Key West in 1994, killing both pilots.
