The problem of the experimental object design for ground experiment system of neutral buoyancy was one of the key to achieving demonstration effectually of the development of spacecraft.

中性浮力地面实验系统的实验体设计问题是有效实现空间飞行器研制阶段地面演示验证实验的关键技术之一。

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Within the next few weeks, the Federal Aviation Administration will issue its regulations surrounding the "experimental permits" that private spacecraft owners will use to test their rockets.

FORBES: To Infinity And Beyond