Once a scramjet is moving fast enough , the jet engine would take over and propel it spaceward .

一旦冲压发动机的运动速度足够快，喷射引擎将接手并将之推动进入太空。

After those six seconds , a shuttle 's twin solid rocket boosters ignite , explosive bolts holding the spacecraft down are severed and the entire stack soars spaceward .

6秒之后，航天飞机的双固体燃料火箭推进器点火，固定航天器的爆炸螺栓切断，整个航天飞机一飞冲天。