If you think Back To the Future Part II was the first time the world was introduced to the concept of hoverboards, think again. As far back as 1955 the US Navy was demonstrating its own hoverboard concept, but unfortunately it wasn't as slick as Hollywood had envisioned them to be.
The craft used a set of counter-rotating propellers pointed at the ground to create a cushion of air that lifted the vehicle and its pilot off the ground. Although, never higher than just a few feet, which was just one of several reasons why the US Navy ended up scrapping the project. It certainly looked stable enough to fly, at least with a skilled pilot in control, but we can't help but feel that referring to it as the 'flying platform' didn't have enough caché to really grab the public's attention. At least not as much as 'hoverboard' has. [YouTube]