Part 3/11:
First on the list of neglected technologies is the Williams X-Jet, developed by Williams International. This vertical takeoff and landing (VTOL) aircraft, powered by a modified F17 turbo fan engine, was designed to be operated solely by one person leaning in the desired direction. Evaluated by the U.S. Army in the 1980s, the project couldn't surpass the capabilities of helicopters and unmanned aircraft, leading to its cancellation. Its innovative design, which included the ability to hover for up to 45 minutes, remains a monumental leap in aerospace engineering that never came to fruition.