Lawrence Stoker wrote a very good article on metal fatigue but he didn’t include man-made fatigue (“Don’t Fly in 10 Years,” Fall 2017). In about 1978, the vice president of maintenance for American Airlines developed a new process of removing the engines from the wing. The normal process was lifting the engine by chains attached to the ceiling. He developed a quicker way by tuning a fork lift. The problem was, every time he used it, it weakened the attachment. The results: In 1979 an American DC-10 taking off from Chicago had an engine fall off and it killed 275 persons on board. 

Larry Green ’46
Brooksville, Florida