Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-400 series airplanes. This AD requires an inspection to detect discrepancies of the main landing gear (MLG) system, an inspection of the jam nut of the retract actuator of the MLGs to ensure the wire lock is in place and the nut is secured, an inspection of the retract actuator for any signs of corrosion or wear, and applicable related investigative and corrective actions if necessary. This AD also requires submitting an inspection report to Bombardier. This AD results from two reports of collapse of MLGs within a few days of each other. We are issuing this AD to detect and correct potential failure of major components of the MLG assembly and attachments, which could result in the possible collapse of a MLG and consequent damage to the airplane and injury to people or damage to property on the ground.