We put extra bolts on the hatches; and, in order to make our sub absolutely silent, we turned off the fans, the cooling system, and all electrical gear.
Investigators have found that four critical bolts were not restored at a Boeing factory to secure the door plug, thereby leading the plug to blow out of the fuselage of a 737 MAX 9 plane in midair.
调查人员发现, 波音工厂未能重新安装四关键螺栓以固定舱门件,导致该件在737 MAX 9飞机飞行途中从机身脱落。