There was a new system of liquid nitrogen to keep the pilot cool and to resist the crushing force of gravity at high speeds.

VOA: special.2010.07.07

One should do," he says, "what archers do when attempting to reach a distant target, namely, aim your bow high, knowing that the force of gravity " will bring the arrow down."

他说：，“一个人应该做的是，模仿伟人所为,当试图达致遥不可及的目标时，意即将目标设高，明了重力会将,射出的箭吸回地面“

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