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To help prevent air crashes caused by tiny mechanical failures, a team from
Iowa State University has found a way of detecting metallurgical problems in
engine components. They have developed a portable eddy current scanner that will
show up hidden defects. The device uses electronic coils to induce a current in
the component. If there are any defects, they disrupt the current. The team鈥檚
efforts were prompted by a fatal plane crash at Sioux City, Iowa, in 1989 in
which a tiny fan disc shattered in a jet engine, severing crucial hydraulic
lines.