Youneverseethem,buttheyarewithyoueverytimeyoufly.Theyre...
问题详情：Youneverseethem,buttheyarewithyoueverytimeyoufly.Theyrecordwhereyou’regoing,howfastyou’retravelingandwhethereverythingonyourairplaneisfunctioningnormally.Theirabilitytostandalmostanydisaster...