Jet engine explosion over Denver rings alarms on shielding

The mid-air disintegration of a jet engine over suburban Denver Saturday is the latest in a string of failures that has raised alarm among regulators about debris evading shielding that’s supposed to keep broken parts from hitting aircraft. The incident aboard the United flight 328, which showered neighborhoods with metal debris, appears to have been the fifth in five years in which a fan blade broke and destroyed the front section of the engine, according to accident reports and safety experts. That portion of the engine isn’t as protected as the core areas around the jet turbines that are built to contain material in a failure. “It’s getting more attention with each fan-blade-out event, resulting in these dramatic pictures showing the core of an engine hanging from a wing,” said Jeffrey Guzzetti, the former head of accident investigations for the US FAA. A similar episode above Pennsylvania in 2018 killed a woman on a Southwest jet after a metal chunk from the engine struck the window where she was seated and sucked her partially out of the jet. The failure raises questions about engine designs that are supposed to prevent debris from escaping out the sides of an engine when a fast-spinning fan blade fails. The FAA told the NTSB last year that it planned to order a design change to prevent such incidents, according to a previously unreported letter last year to the NTSB. “We are working with Boeing to ensure that the corrective action, in the form of a design change, will address the most critical fan blade impact locations,” FAA Administrator Steven Dickson said in a March 9, 2020, letter. Both FAA and the EASA are conducting reviews of their aircraft certification rules to determine whether the standards for engine and aircraft design need to be updated, they have each told the NTSB. The safety board recommended such a review after its earlier investigation of the Southwest fatality. Story has more.<br/>