Piper PA-34-200 N28HE accident near Coldspring, Texas

Probable cause

The stabilator trim rod assembly separated from the stabilator link assembly due to a missing connecting bolt, which resulted in the pilot’s inability to maintain pitch control of the airplane.

NTSB analysis

According to the pilot examiner, following steep turn maneuvers, they heard a loud “pop” from the tail of the airplane, the nose abruptly pitched up, and the airplane entered an accelerated stall. He took control of the airplane and added power to recover from the stall, at which time they heard another loud bang and the nose of the airplane pitched abruptly down. He reduced power to idle, there was another bang, and once again, the airplane pitched up uncontrollably. This time he did not add power and the nose of the airplane pitched down, but not as severely and he was able to use the engine power to dampen the pitch oscillations. Unable to maintain full control of the airplane, he elected for an emergency, off-airport landing. The airplane contacted trees while on approach to the field. The airplane landed hard, bounced, and slid through a rough, muddy field, which resulted in substantial damage to both wings, the fuselage, and empennage.

A postaccident examination revealed that the bolt that connects the stabilator trim rod assembly to the stabilator link assembly was missing and not located.

Since the bolt was not recovered, the reason for the separation could not be determined. Without being able to determine the reason for the separation, the flight school proactively inspected all same model airplanes in their fleet and replaced the bolt on each of them.

Text from the NTSB. Open the NTSB docket for CEN23LA172 for the full record.