My husband thinks it was a flock of birds. Says he's always afraid when he sees some right before they take off. He's a pilot at heart only, though has never flown, so he's really up on aviation information.
In that engine separation crash, the engine broke loose from the pylon but continued to operate for a brief few moments. The engine "ran ahead" of the wing, then swung upward and back over, above the wing, then dropping and bouncing at the very end of the runway. The remaining attachemnts to the pylon wrapped around the wing, slicing through hydraulic systems so that the all control surfaces on that wing were frozen. The plane rolled 90 degrees at it ascended, then crashed across Touhy Avenue into a field, less than 100 yards from a large mobile home park.
It was the next day! They threw a bird at the plane???