Progress on getting this time down further continued through 1949 when the US Air Force flying a b-50 Superfortress made the first flight around the world without stopping to refuel.
1949年,美国空军驾驶 b-50 超级空中堡垒轰炸机首次环球飞行,中途没有停下来加油,在进一步缩短时间方面取得了进展。
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