Innovation in aviation has centered on the development of the jet engine for civil use, first in a turbo propeller form and later as a pure jet.

航空业的革新集中于民用航空喷气式发动机的研发，首先是涡轮螺旋桨发动机，后来是纯粹的喷气机。

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Innovation in aviation has centered on the development of the jet engine for civil use, first in a turbo propeller form and later as a pure jet.

航空业的革新集中于民用航空喷气式发动机的研发，首先是涡轮螺旋桨发动机，后来是纯粹的喷气机。

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