9. Avro Canada VZ-9 Avrocar

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Designed and built by Canada’s Avro Aircraft, Ltd. in 1958 this extraterrestrial-looking craft was part of a secret U.S. military program that aimed to produce a fighter aircraft capable of incredible speed and altitude. As the program progressed, it became more and more apparent that it would never work as intended. It was cancelled in 1961 and never really flew higher than just a few feet above the ground.