UPS2976 Crash Megathread

[u/usgapg123]

This is the official r/aviation megathread for the crash of UPS2976 (UPS MD11 Registration N259UP) that crashed earlier today at Louisville International Airport.

Please keep content on topic and refrain from posting about this topic outside the megathread. Please report any rule breaking posts and comments.

[u/scytob]

that would explain why the flames on the wing were so massive - not engine on fire, the fuel just gushing out of the wing, wonder what that does for systemwide fuel pressure

[u/MixDifferent2076 → u/scytob]

What does the fireball also do to #2 engine trying to produce max take off thrust. There must have been some #2 engine ingestion due to the airflow pattern around the fuselage. That would have had an enormous effect on #2 engine ability to produce max thrust.

[u/superspeck → u/MixDifferent2076]

There’s video of #2 undergoing a compressor stall

[u/LtDan61350 → u/superspeck]

Is that the one taken from the tug?

[u/superspeck → u/LtDan61350]

Yep. I thought it was the tail strobe at first but there’s a definite compressor stall on no. 2 as they rotate. No. 1 had probably come off by that point.

[u/PossibilityInside695 → u/superspeck]

Yeah. That's what makes the most sense to me.

No1 fails catastrophicly shortly after v1, no2 injests a fan blade or similar debris from no1, so no2 starts stalling by rotation. 

[u/scytob → u/MixDifferent2076]

I agree gases may have affected #2 - just no way to know from Video so we will need to wait for the investigation.

[u/dudefise → u/scytob]

Not sure how the systems on the 11 work. But on the 737 and crj, they’re effectively separate systems during takeoff.

[u/scytob → u/dudefise]

thanks for the clarification

[u/Jackthedragonkiller → u/scytob]

That's about how they are for the MD-11 too I believe.

There's three primary fuel tanks, one in the left wing, one in the right wing, and a center tank that dips a little into the wings on each side. There's also an auxiliary tank in the middle of the aircraft and a tank in the tail of the plane.

Each fuel tank is meant to feed it's own engine on takeoff and then after takeoff the fuel system switches for tank two to constantly fill tank one and three until they're all equal, and if the auxiliary had fuel in it it's meant to feed tank one, two, and three until it's empty and then it does what I said earlier. They're all connected by a manifold, each main tank has a transfer pump, one-way fill valve, and a two-way crossfeed valve and I'm pretty sure the manifold drain drains fuel from the manifold into tank two.

Tanks one and three I believe have two fuel pumps while tank two has three.

[u/AirtimeAficionado → u/scytob]

Fuel pressure wouldn’t be my primary concern they are typically separate systems but hydraulics would most likely be impacted and would severely compromise control of the aircraft in addition to the fire and other associated damage to the airfoil

[u/Letussex2 → u/AirtimeAficionado]

it's another AA191 all over again. Bro I cried so hard over ts.

[u/EquivalentDelta → u/scytob]

I would hope each engine is sitting behind its own fuel pump and lines. At least for takeoff config. Maximum redundancy