(CNN) -- Four days after a U.S. civilian-operated cargo jet plunged into the ground shortly after takeoff from Bagram Air Base in Afghanistan, killing all seven people aboard, one expert said that a number of factors likely were involved in the incident. "Accidents, of which this was among the worst that I've ever seen, are typically a confluence of circumstances of seemingly unrelated events, which all coalesce to create a disaster," said Arthur Rosenberg, a pilot, engineer and partner in the New York-based law firm, Soberman & Rosenberg. The doomed plane's final moments appear to have been captured by a dashboard camera inside a vehicle on the base.
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"It really is nauseating to look at," pilot says of plane crash video
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National Air Cargo "will not speculate as to the cause of the accident"
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Military vehicles were "properly loaded and secured," company says
@placeholder, which specializes in moving freight for the military and businesses, did not immediately return a call asking about whether the pilots had, in fact, performed such a takeoff.