On April 16, 2019, at 0750 central daylight time, an Air Tractor AT-502B, N599LA, was substantially damaged when it was involved in an accident near Morganza, Louisiana. The commercial pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight. According to the operator, the pilot heard a loud noise, followed by the nose of the airplane pitching up. The pilot applied full forward pressure on the flight control stick with no response. He then reduced the power to arrest the climb. A company employee, who witnessed the accident, reported that the airplane pitched up dramatically, hesitated, and then pitched almost straight nose-down before it impacted the ground. A postaccident examination of the airplane revealed the aluminum elevator pushrod was disconnected from the forward idler and that the attachment bolt was missing. There was no damage to the forward idler or to the rod end bearing. The missing attachment bolt was later found undamaged in the wreckage. No additional anomalies were noted with the flight controls, airplane, or engine.