When given the task of destroying itself, the human race can be pretty ingenious. The centuries have produced dozens of deadly efficient weapons: Greek fire, the long bow, the Gatling gun, mustard gas, and — of course — the atomic bomb. In order to produce these high-tech killing machines, there were a lot of prototypes that never made it past the drafting board or off the ground.

We don't know what technological concoctions are currently being brewed in the bowels of the Pentagon, but if the failed plans of the 40s, 50s, and 60s are any indication, there are some lethal engineering mistakes being made right now, right under our noses.

By Mack Maloney.