Horace T. Pentecost posing proudly with his invention, the HX-1.
The world envisioned by Mr. Pentecost.
On this Pentecost Day, it is only fitting we mention a man whose name is linked with taking to the heavens and returning to earth: Horace T. Pentecost. In the postwar era, Pentecost toiled on what he thought was sure to be an invention of great value to the people and the military, a lightweight/personal helicopter. A fine idea, but their were difficulties. Among those challenges confronting Pentecost and his HX-1 backpack helicopter was the fact anything less than a perfect takeoff or landing resulted in a disastrously dangerous event involving shards of rotor blades screaming in a hundred different directions. The HX-1 was also very difficult to control, so much so, the only flights made had the machine and its pilot tethered to the earth.
Later models were more stable due to the incorporation of wheels and place to sit, but the late 1940s public (and military) were drawn to the helicopters that were coming off the line from such big name companies such as Bell and Sikorsky.
Mr. Pentecost was no crank inventor; he was an educated man, a wartime Boeing engineer. His dream of a small, lightweight personal means of flight was no different than those who later invented the Ultralight.
The HX-1 was donated to the Smithsonian, and is now on display at the Pima Air & Space Museum in Arizona.
The Jive Bomber 