We've seen helicopters hover both in movies and in real life rescues, even briefly. When put to the test, how long can ...

Engineers at Stanford University in California found that Anna's Hummingbird (pictured) is more efficient than the best micro helicopter Think ... spin their wings to hover, it would cost them ...

Video of the prototype shows the product, which combines a motorbike design with quadcopter technology, flying through the air in a warehouse. The bike is electric-powered and uses four propellers.

Hover over the red squares to read more about the UH-60 Black Hawk heliocopter and the downed helicopter used in the raid on Osama bin Laden's compound (right). Photos of the wreckage of one of ...