Maybe it’s time to say goodbye to the jet pack. For a long while now, when someone mentioned “personal flying machines,” the image that came to mind was of people wearing devices powered by small, but ...

In the 1950s the Navy and Army worked on small VTOL machines to make troops go airborne. They worked, just not well enough.

The promise of personal flying machines has been around for decades. From flying cars to jetpacks, the future always seemed to promise a traffic-jam-free ride to work that left the roads far below.