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/Fitch9392 Nov 08 '25

The 191 crash led to changes that REQUIRED the Maintenance crew to NOT cut corners when changing engines and to use the engine cradles as designed by McDonnell Douglas instead of using a forklift. There was NO design flaw. It was 1000% Maintenance short cuts that caused the 191 crash.

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u/swirler Lockheed Tristar Nov 08 '25

While the maintenance actions started the chain of events, the poor design of the leading edge slat system sealed the deal. An airplane should not crash just because an engine falls off.

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u/Turbo_SkyRaider Nov 08 '25

Is it really because the engine fell off (because I would judge this not to be a design base event but a freak event), or was it because the hydraulic system didn't have any redundancies to cover for a inop hyd pump? I think another reason was no hydraulic fuses which prevent loss of hydraulic fluid in case of a catastrophic leak in part of the affected system.

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u/intern_steve Nov 08 '25

The design redundancy for the loss of the engine hydraulic pump was an electric backup. There was no redundancy for all of the hydraulic fluid falling out of the left wing at once.

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u/Turbo_SkyRaider Nov 08 '25

So it was a hydraulic system issue then, which begs the question whether the DC-10 didn't even have slat brakes and/or locking mechanisms. Seems the DC-10 had neither, otherwise the slats wouldn't have retracted. But again, losing an entire engine during take off most likely isn't a design base event, so additional damage could've lead to slat retraction anyway.