The resulting evolution of its engines has steadily improved fuel efficiency and over the past 30 years has extended the operating life of engines tenfold (to about ten years between major rebuilds).

这种“反馈—改进”模式使得它的引擎的燃料效率稳步提高，在过去30年中，引擎的运行寿命扩展了十倍（引擎两次大修之间的时间达到10年）。

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