The pilot ejected due to a flat spin (just like what happened in Top Gun, RIP Goose). Now a flat spin is a kind of spin and stall that tends to happen when the center of mass and center of lift are in the same place. This can make planes very unstable. So the pilot can't recover and ejects. But this changes the center of mass on the plane, and the plane recovers on its own, and eventually lands itself in a corn field.
The plane was eventually returned to service after repairs.