the Pentagon eventually decided to build helicopters to transport troops into battle. During the opening years of the Vietnam War, the U.S. military began developing and deploying helicopters to ...

[Tom] likes to build little helicopters and decided to build one that runs on compressed air. (Video, embedded below.) Turns out it was a little harder than he thought. Originally, he was trying ...

The discovery is helping experts compete with 42 million years of natural selection to build helicopters that are increasingly efficient, which could match the performance of the best hummingbird.