Alan Diehl, an aviation safety consultant, says federal investigators will examine many possible factors in the mid-air collision near Ronald Reagan National Airport, including the role of fatigue, night vision goggles and nearby aircraft.

Aviation expert explains factors to be investigated in mid-air collision near DCA

Alan Diehl, an aviation safety consultant, says federal investigators will examine many possible factors in the mid-air collision near Ronald Reagan National Airport, including the role of fatigue, night vision goggles and nearby aircraft.