FBI Cannot Rule Out Shootdown of Penn. Plane, It is still not clear why United Flight 93 was the only one of the four hijacked planes not to reach its target. The national consensus seems to have settled around the comforting and plausible evidence that a heroic group of passengers struggled with the terorists onboard, causing it to go down short of its objective. But it had occurred to many early on that the plane might have been intercepted and shot down by U.S. warplanes. None of the eyewitness accounts I’ve heard so far from the Pennsylvania crash site have hinted at this. But would the government tell us, just now, if they had judged that they had to bring the plane down to save, say, the White House? The flight data recorder from the plane, reportedly just found, might have the answers, but would we know?