US NTSB has issued its preliminary report for the ongoing investigation of the Nov. 4 crash of UPS flight 2976, a Boeing MD-11F in Louisville, Kentucky.
The taxi and takeoff roll were uneventful until the airplane rotated for takeoff. Airport surveillance video of the airplane showed the left (No. 1) engine and pylon separating from the wing shortly after airplane rotation, with a fire igniting on the left engine while it traversed above the fuselage and subsequently impacted the ground. A fire ignited near the area of the left pylon attachment to the wing, which continued until ground impact.
The airplane initially climbed but did not get higher than about 30 ft above ground level (agl) according to radio altitude data from the FDR. (Based on FAA-provided ADS-B data, the last data point showed 481 ft mean sea level [msl] and 100 ft agl.) The airplane cleared the blast fence beyond the end of runway 17R, but the left main landing gear impacted the roof of a UPS Supply Chain Solutions warehouse at the southern edge of the airport. The airplane then impacted a storage yard and two additional buildings, including a petroleum recycling facility, and was mostly consumed by fire.
After initial cleaning of the fracture surfaces, examination of the left pylon aft mount lug fractures found evidence of fatigue cracks in addition to areas of overstress failure. On the aft lug, on both the inboard and outboard fracture surfaces, a fatigue crack was observed where the aft lug bore met the aft lug forward face.
The NTSB's investigation of UPS flight 2976 is ongoing.
