3 May 2023: PIPER PA-34-200 (N28HE) — WINGS OVER TEXAS HOLDINGS LLC — Coldspring, TX

No fatalitiesColdspring, TX, United States

A pilot examiner and flight instructor sustained serious injuries after a hardware failure caused uncontrollable pitch oscillations during a certification flight.

What happened

On May 3, 2023, at approximately 1329 central daylight time, a Piper PA-34-200, registration N28HE, was involved in an accident near Coldspring, Texas, while operating as a Part 91 pilot certification flight. The flight was conducted under visual meteorological conditions with a visibility of 10 statute miles and winds from 100 degrees at 8 knots.

Following the execution of steep turn maneuvers, the pilot examiner reported hearing a loud metallic bang from the tail of the aircraft. Immediately following this sound, the control yoke moved to a full nose-up position, causing the aircraft to enter an accelerated stall. The pilot applied full power to recover, but a second loud bang was heard, causing the nose to pitch abruptly downward. After the pilot reduced power to idle, a third bang occurred, and the nose pitched upward uncontrollably once more.

By avoiding further power additions, the pilot was able to use engine power to dampen the resulting pitch oscillations. However, unable to maintain full control, the pilot executed an emergency off-airport landing. During the final approach, the aircraft clipped the tops of trees. Upon touchdown, the airplane bounced and slid through a rough, muddy field, resulting in 2 serious injuries and no fatalities. The impact caused substantial damage to the fuselage, both wings, and the empennage.

The investigation

Post-accident examination of the aircraft revealed that the bolt connecting the stabilator trim rod assembly to the stabilator link assembly was missing. Investigators were unable to locate the bolt, meaning the specific reason for its separation could not be determined.

Maintenance records showed two previous entries regarding the elevator trim wheel cable becoming unspooled, occurring on March 14, 2023, and March 23, 2023. While functional check flights were completed after those repairs, the mechanic involved in the March 23 repair stated he did not perform maintenance on the specific control rod or linkage that failed. The pilot examiner noted that no anomalies were detected during the preflight inspection of the trim linkage assembly.

Probable cause

The separation of the stabilator trim rod assembly from the stabilator link assembly, caused by a missing connecting bolt, which prevented the pilot from maintaining pitch control.

Contributing factors

Not installed/available