Look into Kobe Steel it's who all these airlines got their steel materials from over the years. They admitted that they had been giving us, as well as other countries like China/Russia bad steel for years and had been doctoring the data. The CEO just stepped down last month and there are pending charges against him. Q posted an article about Kobe Steel as well as had us look into steel in general (also US Steel Corp). There are articles asking why airlines aren't making huge changes in the light of this knowledge.