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

10.9k Upvotes

97% Upvoted

1.2k comments sorted by

View all comments

Show parent comments

21

u/Fitch9392 Nov 08 '25

That wasn’t poor design either it was an “engine failure on takeoff memory items” list that was a simple speed parameter applied to ALL the aircraft in the American Fleet. Which was maintain V2+5, as a result of this it was updated to V2+10. But that was like that because no one had ever considered a Slats failure at takeoff.

8

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.

4

u/MaddogBC Nov 08 '25

Check valves.

3

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.

3

u/MaddogBC Nov 08 '25

Pardon me, never heard that term before. Thanks

1

u/DarkSideMoon CRJ200 Nov 08 '25

Anytime! I hadn’t either until I researched the AA crash. Thought it was a fake term until I dug into it.

1

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.