Unleashing the Little-Known VTOL Jet: The Story of Dornier's Do-31

Photo Source - Google

The AV-8B Harrier is a well-known VTOL jet aircraft, but it cannot transport cargo or people other than its pilots.

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In the 1960s, German manufacturer Dornier built the Do-31, a little-known VTOL jet that could transport 36 people.

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The Do-31 used a vectored-thrust Rolls-Royce Pegasus engine, requiring a pair of them.

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Flight tests of the Do-31 were successful, with the jet able to perform vertical takeoff and hovering, as well as conventional horizontal flight.

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Payload capability of the Do-31 was 36 fully equipped troops, up to 11,000 pounds of palleted freight, or 'two or three' Jeeps, with a range of 1,100 miles expected with maximum payload.

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Maximum speed of the Do-31 was approximately 710 km/h (440 mph).

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The Do-31 caught the attention of several American manufacturers at the 1969 Paris Airshow, but no deal was struck.

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The project was abandoned in 1970 due to being too expensive, fuel thirsty, and complex, requiring 10 engines.

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Two of the three Do-31s built are now in German museums.

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