Engine on Southwest jet not the only one to develop cracks

The engine that failed so catastrophically on a Boeing 737 plane operated by Southwest this week is not the only jet engine model with problems that have caught the eye of safety officials. Like the engine on the Southwest jet, two others — one used on the Boeing 787 Dreamliner and another on some Boeing 767s — developed cracks. On Tuesday, the same day as the engine failure on the Southwest plane, the FAA said Boeing 787 Dreamliners powered by Rolls-Royce engines could no longer be flown on ultralong, over-water flights. The engines are produced by three different manufacturers, but the fact that all three have developed safety issues is prompting questions about the engines’ design, operation and their inspection procedures. The worry is that the flaws are part of a trend as manufacturers push to develop ever more powerful and complex machines. “We’ve gotten smarter,” said Richard Giannotti, an aerospace engineer. “We can design things to a very low margin with a lot of reliability data to back it up. But when we get to the ragged edge, it doesn’t take much for things to go wrong.”<br/>He said that in the past, engines were designed with an abundance of precaution. “They don’t do that anymore. They’re trying to whittle down every last bit of material, every bit of weight. Thrust is king.” But, Giannotti said, “there is such a thing as pushing things. We try to get right to the edge, with as little edge as possible, without stepping over." In the case of the Southwest engine failure this week, investigators say they are not only considering why a fan blade broke but why the engine housing failed to contain it. <br/>