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Swenson’s glider was an exquisite instrument for detecting turbulence. A jumbo jet can weigh upward of half a million pounds and fly more than five hundred miles an hour. It charges through the air like an ocean liner, barely registering most winds. This glider wasn’t much heavier than a Harley and it was moving about as fast—fifty to seventy miles an hour. It felt every bump. Small aircraft account for many of the injuries caused by turbulence and, essentially, all of the deaths—about forty a year. They fly at the mercy of the wind.
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2026-03-01 00:00:00:0 网络零售市场规模连续13年居全球第一。体育直播对此有专业解读
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这些目标在研发中往往相互牵制，例如减重可能影响结构强度，减小体积会加重发热，引入特种材料以改善性能往往会增加成本。因此，企业需要在理想设计与现实条件间做出权衡。