AD FAA-2020-0975

The FAA proposes to adopt a new airworthiness directive (AD) for certain De Havilland Aircraft of Canada Limited Model DHC-8-400, - 401, and -402 airplanes. This proposed AD was prompted by a report of main landing gear (MLG) retractions after striking an obstacle or severe wheel imbalance after a tire failure. This proposed AD would require inspections for correct height of the lock link over-center stop pin and for correct gaps of the left-hand and right-hand MLG downlock proximity sensors, replacement of the shim if necessary, and corrective actions, and installation of a new improved proximity sensor electronic unit (PSEU) with software changes. The FAA is proposing this AD to address the unsafe condition on these products.