黑顺片为什么要先煎一个小时

　　From the crash of Air France flight 447 between Rio and Paris into the Atlantic in 2009, to the Germanwings flight 9525 crash in the Alps in 2015, the French investigators of the BEA (Bureau of Enquiry and Analysis for Civil Aviation Safety) are called upon worldwide to determine the causes of air accidents. Line planes, helicopters, ultra-lights: BEA is investigating everythin... (展开全部)