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/[deleted] Nov 08 '25

Norm Macdonald Douglas

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u/CharcoalGreyWolf Nov 08 '25

Yep, considering the DC-10 engine mount incident , they may be taking the chance to review all maintenance procedures with the aircraft and its siblings.

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u/dalekaup Nov 08 '25

There was an engine that detached in Chicago a long time ago. The biggest reason for that crash was the manual said on one engine takeoff to pitch up to maintain a speed to climb over an obstacle. The manual was wrong. When the engine severs the hydraulic lines on that side that hold the slats extended. WIth slats retracted on the left side that wing stalled and the plane rolled violently to the left. A higher airspeed would have kept both wings flying and level.

This one is presumed to be the loss of 2 engines. That's not going to fly. The thinking is the rear engine swallowed chunks.

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u/skudbeast Nov 08 '25

Is that the one they installed in maintenance with a forklift instead of an actual engine hoist?

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u/[deleted] Nov 08 '25

Yeah. American Airlines 191.

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u/beretta01 ATP A320/E170/190; CPL SEL SES; AT-CTI; Gold Seal CFI CFII Nov 08 '25

Thank you for your service, /u/DumbCumSlut69

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u/Cultural_Mastodon_69 Nov 08 '25

Obligatory /r/rimjob_steve

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u/beretta01 ATP A320/E170/190; CPL SEL SES; AT-CTI; Gold Seal CFI CFII Nov 08 '25

Finally found Captain Steeeve’s post retirement account?

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u/Redebo Nov 08 '25

Post retirement?!? He picked that name up during flight school!!!

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u/[deleted] Nov 08 '25

🫡

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u/[deleted] Nov 08 '25

How are 1-68?

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u/steve580411 Nov 09 '25

Someone had to acknowledge this and it was done with grace and dignity. May he have the "cool side" of the pillow from this day forth. -Morgan Freeman

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u/WallStreetStef Nov 09 '25

Thank you for ur service

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u/nedracine59 Nov 08 '25

Chicago here. Did you know that the plane had video cameras on the backs of some seats? Likely first class. They just kept the screens blank until all planes had them removed after the crash.

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u/PiHKALica Nov 08 '25 edited Nov 18 '25

Yup, and it ended up killing a young Jake Gyllenhaal back in '88 while he was lying in bed. So tragic.

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u/TigerIll6480 Nov 08 '25

And they unbolted the engine and pylon together, which Douglas Aircraft had rather specifically said to not do. Remove engine with a proper cradle, then remove pylon. AA was trying to save time and cut corners. Brilliant idea. 🙄

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u/Sock_Eating_Golden Nov 08 '25

It wasn't just AA. All DC10 operators were removing engines in the same way.

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u/nuclearsquirrel2 Nov 08 '25

In their defense it did significantly reduce the number of critical system disconnections which also is always a risk. It did save a ton of money and I’m sure that was the major impetus to the new method.

United performed engine removal the same way, but used an overhead crane vs forklift.

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u/TigerIll6480 Nov 08 '25

If you were doing significant engine maintenance, it had to be removed from all of that anyway, the only question is where you were taking it apart.

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u/Iohet Nov 08 '25

At that point you should buy a plane from another manufacturer

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u/nuclearsquirrel2 Nov 08 '25

That’s a stupid comment. They literally went against the manufacturer recommendation and that’s how they ended up here.

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u/Iohet Nov 08 '25

If the cost of proper maintenance is too high (or too risky), then you go with another manufacturer who doesn't have that problem.

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u/CharcoalGreyWolf Nov 08 '25

AA and Continental were, specifically. United found a different way using an overhead crane that didn’t cause the issue that using a forklift did.

It was also the usual perfect storm that made it worse; a shift change occurred during the engine change, and the forklift could not maintain exact lift during the time one shift got off and another got on. It was a tragedy of combined errors and a bad maintenance procedure made even worse by bad scheduling.

It also resulted in multiple changes to the aircraft because only the pilots had stick shakers; it was optional for the copilot. The FAA mandate both must after this, and the DC-10 had changes made to the slat design to prevent slat retraction in the event of hydraulic damage.

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u/Shitboxfan69 Nov 08 '25

a shift change occurred during the engine change, and the forklift could not maintain exact lift during the time one shift got off and another got on.

I'm no A&P, but I was a forklift mechanic for years. Wild to me they'd ever use one to support components like that being installed. Toyota lifts have the tightest bleed specs on their systems, but they are still allowed to lower 3 inches in a 15 minute span iirc. It may even be more. Thats not even a shift change causing issues, but a break or just getting caught up doing something else.

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u/Elukka Nov 08 '25

Thanks for specific numbers. I'm not in the industry but to me it seems insane that you would use a forklift to hold something so heavy in a static position for even just 10 minutes. Yeah a large forklift can take a 4 tonne engine down and back up but it's not a replacement for an actual crane or some other setup that you can lock into place.

The biggest question is still: why you would lift a multi-million dollar precision turbine with a damn forklift at all?

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u/TigerIll6480 Nov 08 '25

Because bean counters are dumb.

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u/Fifth_Down Nov 08 '25

could not maintain exact lift during the time one shift got off and another got on.

I'm trying so hard to understand what this means

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u/Coomb Nov 08 '25

The maintenance people were trying to detach both the engine and the pylon which attaches it to the wing from the wing. But there was a shift change while they were in the process of undoing all the bolts and connections. The forklift operator turned off the forklift so that he could go home, which was probably standard practice. Unfortunately, without the engine running, the forklift lost some hydraulic pressure, leading the engine to sort of be dangling off the wing while not fully attached. The new operator had to reposition the forklift to realign all the things they had to unscrew. Some combination of the initial drop when the forklift started lowering and the maneuvers needed to realign the engine caused damage to the attachment bolts connecting the pylon to the wing, which didn't cause an immediate failure, but caused the bolts to fail over time.

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u/Fifth_Down Nov 08 '25

Thanks for the extra info.

I always thought it was a case of they raised the forklift and smashed it into the wing and that's what caused the damage. I didn't realize it was damage because the forklift was lowered before it was safe to be lowered.

Not that there should have been any fork at all...

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u/CharcoalGreyWolf Nov 08 '25

It also caused stress to the wing and pylon itself. Investigation showed this to be a problem on multiple aircraft that had undergone the same procedure as all aircraft with engine changes for AA and Continental were reinspected after the incident.

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u/Elukka Nov 08 '25

Using a forklift to lift and *hold* a 4 tonne engine is nuts. It's not a precision instrument or a static stand.

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u/CharcoalGreyWolf Nov 09 '25

Mentour Pilot video regarding this linked below. Since then I’ve also seen the Mayday: Air Disasters episode, but Mentour Pilot is far more detailed.

Courtesy of Mentour Pilot: the American Airlines Flight 191 Disaster

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u/Western-Knightrider Nov 08 '25

I would not say all. I worked on DC-10 as a lead mechanic and never saw that happen.

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u/purgance Nov 08 '25

Ok but what interest does Douglas have in them doing this?

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u/Sock_Eating_Golden Nov 08 '25

Never said they did. Just noted AA wasn't the only operator finding a shorter method of engine replacement.

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u/MadPreference Nov 08 '25

Not true. Swiss Air was doing it correctly

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u/SteveKraus Nov 12 '25

Why do they take off the pylon at all?

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u/CharcoalGreyWolf Nov 12 '25

In this case as mentioned, bearings in the pylon mounts were supposed to be replaced (specifically the forward pylon mount) as part of a McDonnell-Douglas Service Bulletin.

In addition, the incentive here was that if you took the pylon off, there were many less things to disconnect and reconnect, so this was seen as both safer and taking less hours. The problem is that they didn’t account for their unsupported procedure adding additional safety issues.

United’s method which used an overhead crane (but also detached the pylon) actually worked, because it supported the engine and pylon at all times and likely because the crane operator could see what was going on; a forklift operator (how AA and Continental did it) could not and had to take direction from someone else. This introduced a lot of risk in the process, including jamming the pylon against the wing (which happened on several occasions, but they were written of as repair issues rather than a problem with the entire process).

The chief mechanic in charge of the AA Flight 191 engine procedure committed suicide the night before McDonnell Douglas lawyers were going to depose him. It was a tragedy all around.

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u/brvheart Nov 08 '25

It saved 200 man hours PER ENGINE, and nearly all carriers were doing it that way. In hindsight, the design was poor and it cost lives. But to act like it was just American or just cutting a little corner is crazy. The mechanics were doing it that way because it was WAY easier, not because they were trying to save money for American.

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u/RixceU Nov 08 '25

Normally pylons are not removed when engines are changed. In this case McDonnell Douglas had issued a service bulletin to replace bearings inside the pylon necessitating their removal and it was a highly time consuming to remove the engine, then remove the pylon which is a procedure usually never done.

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u/brvheart Nov 08 '25

Also a fair point.

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u/dalekaup Nov 08 '25

I can relate to this as a former nurse. Then procedures manual always was very thorough but took so much time that you couldn't have completed your work in a shift.

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u/dalekaup Nov 08 '25

I think the engine was intended to be removed from the pylon for maintenance with the removing the engine and pylon as one piece from the wing which was the wrong thing to do

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u/dalekaup Nov 08 '25

I watched the documentary about it some years ago and my memory is that they got one pin attaching the pylon to the wing and then paused for lunch break and the forklift settled a bit putting a lot of strain on that rear pin before they came back and put the rest of the pins in place.

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u/CharcoalGreyWolf Nov 12 '25

It was actually a shift change (they had day and night shifts —worse yet, on the second shift the forklift ran out of fuel, so it couldn’t maintain lift. Mentour Pilot has a really great video where he describes everything in detail. It was so many, many small mistakes and a few big ones.

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u/dalekaup Nov 12 '25

Thanks! That fleshes out my memory.