Denver plane engine fire consistent with metal fatigue, investigators say February 23, 2021 Metal fatigue may have caused an engine explosion during a United Airlines flight over Denver on Saturday, investigators say. Latest posts Pfizer/BioNTech vaccine shows promise against Brazil coronavirus variant in laboratory testing Read more Pfizer/BioNTech vaccine shows promise against Brazil coronavirus variant in laboratory testing Read more Hollywood backs ‘Team Meghan’ as Royal racism allegations grip La La land Read more