Thinking Sideways: Area 51 Broadcast Interruption

On September 11, 1997, on Art Bell's Coast to Coast AM show, a frantic caller claiming to be a recent employee at Area 51 made some startling revelations. A few minutes into the call, the Coast to Coast AM broadcast is mysteriously disrupted. Seventeen years later, a man calls a different show called Fade to Black, claiming to have made the whole thing up. Was the call really a hoax? And if so, what took out the broadcast?