Helical Air Screw

• In 1480, Leonardo da Vinci sketched the "Helical Air Screw" or "air gyroscope." Da Vinci envisioned the machine to be built with a reed, wire and starched linen. The mechanism, powered by four men simultaneously rotating cranks at the central platform of the aerial gyroscope, would compress air to gain flight. Today's helicopters contain a faint resemblance to the early air-screw.
  
  

Ford Nucleon

• The Ford Company designed the Ford Nucleon in 1957 in an attempt to invent an automobile that would not emit dangerous gases. Powered by a small nuclear reactor located at the rear of the car, it was expected to cover a distance of 5,000 miles per charge. Ford's ambitious project was eventually scrapped after concerns on refueling, bulky machinery and nuclear waste were failed to be solved by its designers and engineers. The Nucleon only got as far as a 3-foot model scale.
  
  

Pipeline from the North Pole to the Sahara Desert

• Arthur Paul Pedrick was a British inventor in the 1960s and 1970s. He applied for many patents for his invention ideas that were believed to be mostly impossible or too impractical to actually be made. One of his invention ideas was the construction of a very long pipeline from the North Pole to the Sahara Desert. The pipeline's purpose was to water the Sahara. He believed irrigation of the desert would solve problems such as world famine if his invention came into completion.
  
  

Low-Flying Multi-Composite Plane

• Another invention idea by Arthur Paul Pedrick, brings together four or five Boeing 747s to form an aircraft with retractable wings intended to be flown at low levels over the sea or any land surface. Its design for low-altitude flying gears the aircraft for emergency landings if in any event it encounters an emergency.