A UPS cargo plane crashed earlier this month after its left engine broke off just after takeoff, killing 14 people, including those on the ground. A preliminary investigation by the National Transportation Safety Board (NTSB) revealed that the engine’s turbine mount had cracks caused by metal fatigue, weakening the structure that held the engine.
The plane, a McDonnell Douglas MD-11F, was taking off from UPS’s main hub in Louisville, Kentucky, on November 4 when the engine suddenly detached. The plane barely climbed above 30 feet before crashing in a fiery impact. Dramatic images from the report show the engine and its pylon flying into the air right after the plane left the runway.
Experts say this accident is very similar to a 1979 crash involving an American Airlines DC-10, where the left engine also separated shortly after takeoff. However, the UPS incident involved different parts of the engine mount and, so far, investigators have not found signs of external damage or maintenance errors in the same way as the earlier crash. Instead, the wear seems tied to the age and condition of the parts.
After the crash, the Federal Aviation Administration (FAA) ordered an immediate grounding of all MD-11F cargo jets to carry out detailed inspections and make necessary fixes. This directive was later expanded to other aircraft with similar engine mounts. The grounding affects about 9% of UPS’s fleet and around 4% of FedEx’s cargo planes.
UPS said it had already stopped flying its MD-11 planes before the FAA’s order, as a safety precaution. Both UPS and Boeing, which now owns McDonnell Douglas, are cooperating with the ongoing investigation.
The NTSB also noted that the plane had a thorough visual inspection of the left engine mount back in October 2021. A more detailed check of the exact part that failed wasn’t scheduled until much later—after thousands more flights. The failure happened well before the expected inspection time.
The plane involved was built in the early 1990s for Thai Airways before being converted into a freighter about 20 years ago. Its engines are General Electric CF6 models. The MD-11 no longer carries passengers and is only used for cargo today.
Final conclusions on what caused the crash might take up to two years as investigators examine all the details. Meanwhile, this tragedy has brought a sharp focus on the maintenance and safety of aging cargo planes.