The Williams Aerial Systems Platform II aka Williams X-Jet, created by Williams International, was a small, light-weight Vertical Take Off and Landing (VTOL) system powered by a modified Williams F107 turbofan aircraft engine. This vehicle was nicknamed "The Flying Pulpit". It was designed to be operated by and carry one person and controlled by leaning in the direction of desired travel and adjusting the power. It could move in any direction, accelerate rapidly, hover, and rotate on its axis, staying aloft for up to 45 minutes and traveling at speeds up to 60 miles per hour (100 km/h). It was evaluated by the U.S. Army in the 1980s, and was deemed inferior to the capabilities of helicopters and small unmanned aircraft.