United Airlines Flight 328
2021 B777-200 airliner incident with PW4000-112 engine failure over Broomfield, CO, USA
On February 20, 2021, United Airlines Flight 328, a scheduled domestic flight from Denver to Honolulu, suffered a contained engine failure shortly after takeoff from Denver International Airport (DEN). The aircraft, a Boeing 777 powered by Pratt & Whitney (P&W) model PW4077 turbofan engines, experienced a fan blade separation due to metal fatigue causing an engine fire and extensive damage to the nacelle. Despite being classified as a contained failure, as the fan blade fragments remained inside the nacelle, large parts of the engine's cowling, inlet and thrust reverser detached, creating a debris field over 1 mile (1.6 km) long across residential areas of Broomfield, Colorado.
The falling debris damaged private property, including the roof of a home and a parked vehicle. Witnesses captured footage of falling debris on smartphones and a dash cam, while passengers recorded video of the damaged engine and posted it to social media. The fuselage sustained minor damage, but the crew was able to shut down the affected engine and return safely to Denver, landing on runway 26 at 1:28 pm MST (06:28 UTC), 24 minutes after departure. No injuries were reported among the 231 passengers and 10 crew, or on the ground.
The U.S. National Transportation Safety Board (NTSB) opened an investigation into the incident. In response, the U.S. Federal Aviation Administration (FAA) issued an Emergency Airworthiness Directive requiring immediate inspection of Pratt & Whitney PW4000-series engine fan blades before further flight. Similar 777-200 aircraft were temporarily grounded by multiple aviation regulators around the world.
The public source identifies “United Airlines Flight 328” as 2021 B777-200 airliner incident with PW4000-112 engine failure over Broomfield, CO, USA. This brief keeps that definition visible, then builds a research path around United, Airlines and Flight.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Apr 12, 2026. The linked authority identifier is Q105612231. Authority coordinates are 39.929, -105.055. None of the 1 selected statements returned an explicit reference. The first chronological checks are 2021.
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This entry incorporates text from “United Airlines Flight 328” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.