the Hughes XH-17, a prototype Flying Crane

The XH-17 began as a ground test stand for a huge tip-jet-powered rotor system. In 1949, Hughes Aircraft got a contract to turn it into a flying machine. The giant rotors promised a huge lifting capacity, so they were attached to stilt-like legs and a box-like fuselage. Cargo such as radar vans could be driven underneath and lifted away.

as an operational aircraft the XH-17 was just too bulky and cumbersome to be practical and had a range of only 64km, well below the US Army's requirement. The rotor blades were subject to vibration stresses and the XH-17 was frequently grounded. After three years of sporadic testing, the whole programme came to an end when the one set of rotors reached the end of its design life.

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