Question: The Lisunov Li-2, originally designated PS-84, was a license-built version of the Douglas DC-3, a fixed-wing propeller-driven airliner, its lasting effect on the airline industry, and which event makes it one of the most significant transport aircraft ever made?
Related documents: [0]  [DOC] The Lisunov Li-2, originally designated PS-84, was a license-built version of the Douglas DC-3. It was produced by Factory #84 in Moscow-Khimki and, after evacuation in 1941, at TAPO in Tashkent. The project was directed by aeronautical engineer Boris Pavlovich Lisunov. [END] 
[1]  [DOC] The Douglas DC-3 is a fixed-wing propeller-driven airliner. Its cruise speed (207 mph ) and range (1500 mi ) revolutionized air transport in the 1930s and 1940s. Its lasting effect on the airline industry and World War II makes it one of the most significant transport aircraft ever made. [END] 
Answer: 
World War II
World War II