{"id":25581,"date":"2021-03-30T02:00:00","date_gmt":"2021-03-30T06:00:00","guid":{"rendered":"https:\/\/blogs.sw.siemens.com\/simcenter\/?p=25581"},"modified":"2026-03-26T06:39:45","modified_gmt":"2026-03-26T10:39:45","slug":"containing-aircraft-engine-failure","status":"publish","type":"post","link":"https:\/\/blogs.sw.siemens.com\/simcenter\/containing-aircraft-engine-failure\/","title":{"rendered":"Containing aircraft engine failure"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">Problems Arise<\/h2>\n\n\n\n<p>Last month, during a <a href=\"https:\/\/www.youtube.com\/watch?v=Bjs9Diyq0w0\" target=\"_blank\" rel=\"noreferrer noopener\">routine flight from Denver to Honolulu an uncontained engine failure occurred<\/a>. Fortunately, the pilots were able to follow through with their training and safely land the plane back in Denver. Technically however per the NTSB (National Transportation Safety Board):<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p><a href=\"https:\/\/www.flightglobal.com\/safety\/prior-united-777-blade-out-might-give-clues-to-ua328-engine-structure-loss\/142640.article\" target=\"_blank\" rel=\"noreferrer noopener\"> \u201c\u2026 by our strictest definition, do not consider this to be an uncontained engine failure\u2026 because the containment ring contained the parts as they were flying out.\u201d<\/a> <\/p><cite>&#8211; Robert Sumwalt, US National Transportation Safety Board Chairman <\/cite><\/blockquote>\n\n\n\n<p>The key to understanding this statement is the meaning of &#8220;uncontained&#8221; and ultimately the science of predicting engine failure.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Root Cause<\/h2>\n\n\n\n<p>What occurred <a href=\"https:\/\/aviationweek.com\/mro\/safety-ops-regulation\/metal-fatigue-signs-link-united-777-fan-blade-failure-2018-incident\" target=\"_blank\" rel=\"noreferrer noopener\">is similar to an event in 2018<\/a> where a blade-out event occurred. The root cause was low cycle metal thermal fatigue of the turbofan blades.&nbsp; Understanding how CAE simulation can predict such fatigue is worthy of a blog post of its own. But <em>why <\/em>did such a mechanically devastating event <em>not <\/em>lead to a catastrophic failure and loss of life?<\/p>\n\n\n\n<p>To understand this, we need to look at what happened immediately after the blade out. <a href=\"https:\/\/www.youtube.com\/watch?v=WtMZSyjXQUU\" target=\"_blank\" rel=\"noreferrer noopener\">In this footage,<\/a> the turbine engine continues to rotate but is visibly vibrating under an <strong>unbalanced <\/strong>load.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Containing Engine Failure with Rotor Dynamics<\/h2>\n\n\n\n<p>The engineers were able to account for these unbalanced loads because they used CAE simulation. The science of rotor dynamics can deliver key insights by understanding and predicting unbalanced loads.<\/p>\n\n\n\n<p>Rotating machinery is incredibly powerful and efficient at generating and distributing power but it is essential these dynamic structures remain in equilibrium. The rotating components should not hit critical speeds that <em>amplify <\/em>the <a href=\"https:\/\/community.sw.siemens.com\/s\/article\/Natural-Frequency-and-Resonance#:~:text=Natural%20Frequency%3A%20All%20physical%20structures,are%20distributed%20within%20the%20structure.\" target=\"_blank\" rel=\"noreferrer noopener\">natural frequencies<\/a> or order of the system. Avoiding amplification of the <em>resonance <\/em>of the static structure surrounding the rotors is important as well.<\/p>\n\n\n\n<p>The critical operation point is where the order and the resonance meet. The operation points on United 328 fortunately <strong>never <\/strong>met the operation points after the blade-out event. Therefore accounting for the unbalanced loads prevented this unfortunate incident from being something much worse. <\/p>\n\n\n\n<p>So how do Aero-engine manufacturers meet such rotor dynamics challenges? By using <a href=\"https:\/\/www.plm.automation.siemens.com\/global\/en\/products\/simulation-test\/dynamics-simulation.html\" target=\"_blank\" rel=\"noreferrer noopener\">Simcenter 3D Rotor Dynamics<\/a> software. In <a href=\"https:\/\/www.plm.automation.siemens.com\/global\/en\/webinar\/rotor-dynamics-analysis-aircraft-engine\/94222\" target=\"_blank\" rel=\"noreferrer noopener\">this on-demand webinar<\/a>, &#8220;Rotor dynamics analysis for better operational efficiency of aircraft engines&#8221;, you can learn how Simcenter 3D provides proven strategies to overcome these and other engineering challenges.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/www.plm.automation.siemens.com\/global\/en\/webinar\/rotor-dynamics-analysis-aircraft-engine\/94222\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"124\" src=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Watch-on-demand-webinar-1-1024x124.png\" alt=\"\" class=\"wp-image-25606\" srcset=\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Watch-on-demand-webinar-1-1024x124.png 1024w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Watch-on-demand-webinar-1-600x73.png 600w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Watch-on-demand-webinar-1-768x93.png 768w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Watch-on-demand-webinar-1-900x109.png 900w, https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Watch-on-demand-webinar-1.png 1348w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/a><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Accounting for the unbalanced load by the use of rotor dynamics software ensured the engine failure of UA 328 was contained.<\/p>\n","protected":false},"author":56480,"featured_media":25593,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spanish_translation":"","french_translation":"","german_translation":"","italian_translation":"","polish_translation":"","japanese_translation":"","chinese_translation":"","footnotes":""},"categories":[184],"tags":[331,5,243,251,98,63605],"industry":[125,126],"product":[577,499,581],"coauthors":[14784],"class_list":["post-25581","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-webinar","tag-wheretodaymeetstomorrow","tag-cae-simulation","tag-computer-aided-engineering-cae","tag-finite-element-analysis","tag-finite-element-method","tag-rotor-dynamics","industry-aerospace-defense","industry-aircraft-engines","product-simcenter-3d","product-simcenter-cae-solutions","product-simcenter-nastran"],"featured_image_url":"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2021\/03\/Containing-Engine-Failure-crop.jpg","_links":{"self":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts\/25581","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/users\/56480"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/comments?post=25581"}],"version-history":[{"count":5,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts\/25581\/revisions"}],"predecessor-version":[{"id":72394,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/posts\/25581\/revisions\/72394"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/media\/25593"}],"wp:attachment":[{"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/media?parent=25581"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/categories?post=25581"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/tags?post=25581"},{"taxonomy":"industry","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/industry?post=25581"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/product?post=25581"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/blogs.sw.siemens.com\/simcenter\/wp-json\/wp\/v2\/coauthors?post=25581"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}