Over-Serviced Tail Wheel Strut Leads to Runway Excursion and Gear Collapse (N2996Q)

Incident Overview

During a landing in a crosswind, the pilot of an aircraft experienced vibration from the tail wheel. The vibration was followed by a failure of the tail wheel bellcrank due to torsional overstress. This resulted in a loss of tail wheel steering control, causing the aircraft to run off the right side of the runway. The main landing gear subsequently collapsed.

Findings

Examination revealed that the tail wheel strut had been over-serviced, causing it to be extended higher than normal. This condition made the aircraft harder to steer. The excessive extension likely contributed to the torsional overstress that led to the bellcrank failure.

Sequence of Events

• The aircraft approached and landed in a crosswind.
• During the landing roll, the pilot noted vibration from the tail wheel.
• The tail wheel bellcrank failed due to torsional overstress.
• With the loss of tail wheel steering control, the aircraft departed the runway to the right.
• The main landing gear collapsed during the excursion.