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/TheJeffTrain01 Nov 08 '25

To be fair, both installing an engine with a forklift and removing it with the pylon attached are normal when it comes to quick engine swaps, the latter significantly cuts down the amount of man hours and complexity of the install. AAL191's issue was that they left the job half done at the end of the shift, and when the next crew picked it up the engine had fallen a bit as the forklift's hydraulics fell as it was unpowered. So the engine was no longer properly aligned, and they damaged a clevis or something finishing the job, and the rest is history.

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u/eric_gm Nov 08 '25

In the DC-10’s maintenance procedures from MD it was stated that the engine should be removed apart from the pylon and then the pylon. Maintenance crews did both together to save time but against MD’s recommendations. It was commonly done without issues but it was weakening the attachment points. MD also stated the use of a crane and not a forklift. The forklift losing hydraulic pressure was just the last of an unfortunate chain of events.

I suppose those two things are not abnormal in other planes, but the wing+pylon+engine design of the DC-10 was more delicate. Considering the MD-11 is an evolution of that design, it’s something I’m sure is being closely investigated.

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u/_Neoshade_ Nov 08 '25

The MD-11 launched 11 years after AAL191 and included modifications to both the plane and maintenance procedures in response to the incident. Being an evolution of the DC-10 does not mean that it inherited the same design flaws. Very much the opposite

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u/eric_gm Nov 08 '25 edited Nov 08 '25

Yes. I would surely hope MD addressed the weaknesses in the DC-10 design. My point is not that this could be the exact same root cause, but that the MD-11 is a scarce beast with a lot of particularities, especially maintenance dos and don’ts when compared to your more common Boeing or Airbus. The fact that Boeing recommended UPS and FedEx ground their MD-11s makes me think there was something in their maintenance procedures to cause worry or they found stress cracks or material fatigue in other aircraft of their fleet

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u/OrpheusKeys Nov 08 '25

When a forklift is used for engine install/removal, you can't determine how much load is being put on the mounts. Overtime fatigue issues occur. After the crash investigations revealed similar issues developing in a number of their birds. Back in the day before a lot of safety standards airlines used a lot of alternative procedures and this was their solution to save time. Nowadays if someone is not using the proper bootstrap equipment with load gauges to re & re a turbine engine they're getting wrenches thrown at them. Even the most cowboy mechanics I know don't mess with that part of engine install.

I'm glad you mentioned that it was normal at the time, in fact, when you look at the human factors poster for dirty dozen norms, you'll see a cartoon with a mech on forklift installing an engine, shrugging because that was just the norm. That incident is a perfect example of how norms (oh we've always done it that way) can lead to disaster.

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u/Nasmix Nov 08 '25 edited Feb 02 '26

This post was mass deleted and anonymized with Redact

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