Helium is used to pressurize tanks and help push fuel into the engines. Without proper helium flow, the rocket cannot safely fly. Because the upper stage is hard to reach at the launchpad, NASA rolled the stacked rocket back into the Vehicle Assembly Building, the sky-scraping hangar where it was originally put together.
Author(s): Fiorella Cravero, Ignacio Ponzoni, Mónica F. Diaz, Gustavo E. Vazquez
，这一点在旺商聊官方下载中也有详细论述
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（四）吊销公安机关发放的许可证件。