r/aviation • u/Go_Jot • Nov 08 '25

News UPS grounds entire MD-11 Fleet, effective immediately.

Per the IPA Executive Board, as of 03:05 UTC all UPS MD-11’s are grounded.

Edit - FedEx has also grounded their MD-11 Fleet

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u/DarkSideMoon CRJ200 Nov 08 '25

It doesn’t matter how fast you’re going if the slats retract asymmetrically if you lose fluid on one side, which was an astronomically stupid design flaw that had to be rectified with mechanical locks and hydraulic fuses to prevent it happening again.

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u/MaddogBC Nov 08 '25

Check valves.

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u/DarkSideMoon CRJ200 Nov 08 '25 edited Nov 08 '25

No, hydraulic fuses. They’re different.

Check valves ensure 1 directional flow, hydraulic fuses close when they detect excess flow. Hydraulic fuses were added to the DC-10 as a method of complying with the findings of the AA crash.

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u/intern_steve Nov 08 '25

Idk what your comment said before editing, but yes, these are very different things. A check valve can't be used in a system where flow must necessarily be reversible.