Federal investigators have released photos of an engine flying off a doomed UPS cargo plane that crashed after an engine flew off, killing14 people in Kentucky two weeks ago.

NTSB investigators "found evidence of fatigue cracks in addition to areas of overstress failure."

The agency’s report cited the 1979 crash of an American Airlines DC-10 at Chicago-O’Hare International Airport that killed 271 people and two people on the ground. Similar to the UPS crash, the airliner’s engine and pylon fell off as the craft was taking off. MD-11s are essentially larger, modernized versions of the DC-10.

The cargo plane was taking off from Louisville earlier this month when it crashed moments after becoming airborne, killing the three crew members and 11 people on the ground.

Frame by frame, six photos released by federal investigators capture horrifying images of ill-fated Flight 2976 as it turned into a fireball along a Kentucky airport runway.

The National Transportation Safety Board said on Thursday it has found evidence of fatigue cracks in a key part of a UPS MD-11 cargo jet that crashed this month in Kentucky, an important clue into the cause of the incident that killed 14.