another article in Military.com

sample quote

A mechanical failure known as a hard clutch engagement, or HCE, has plagued the Osprey for more than a decade, with at least 15 known incidents occurring between 2010 and 2022.

An HCE happens when the aircraft's clutches -- which when working properly allow for one engine to power both propellers -- jam and shred internal components connected to the rotors.

One essential component that can wear out and lead to a clutch failure is the input quill assembly.

While the incident is still under investigation, the Air Force noted that preliminary indications in the November crash that killed eight airmen indicated a "potential materiel failure."

An Air Force Special Operations Command official told Military.com last week that preliminary findings in the Nov. 29 mishap show that the flight hours on the input quill assembly were likely below the 800 flight hour threshold for replacement that was announced in February.

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https://www.military.com/daily-news...s-are-limiting-their-use-operations.html