READ MORE: Researchers have found the risk of a small military drone having an impact with civilian aircraft is low , with a catastrophic event ocurring no more than once every 1 million years , according to a recently released study from George Washington University .
Researchers have found the risk of a small military drone having an impact with civilian aircraft is low , with a catastrophic event ocurring no more than once every 1 million years , according to a recently released study from George Washington University .