Planes and helicopters have their strengths and weaknesses. Planes are fast and can carry a lot of stuff a long way, while helicopters are slow but they don't need enormous runways and they're extremely maneuverable. So naturally, people want to combine them.

That's why a team at NASA's Langley Research Center is developing a drone that's a hybrid of the two.

The GL-10 Greased Lightning is a ten-engine, battery-powered prototype with a ten-foot wingspan that can change its shape midair to fly either horizontally or vertically. This month, NASA announced it recently took off vertically and, for the first time, successfully rotated its wings to transition from "helicopter" mode to standard "wingborne" flight.

The GL-10 is a relative of the V-22 Osprey, the VTOL (vertical takeoff and landing) aircraft developed in the 1980s for the US Air Force and Marines. It's a tiltrotor design: The engines rotate to propel the aircraft either up and down (like a helicopter), or forward (like a propeller-driven plane). The Osprey can take off and land from the deck of a carrier or from a field in the middle of the jungle, instead of from a lengthy runway. It can haul 32 troops or 20,000 pounds of internal cargo up to 2,200 miles. It's very handy.