Summary
We propose to adopt a new airworthiness directive (AD) for certain Airbus Model A319, A320, and A321 series airplanes. This proposed AD was prompted by investigations that revealed that the cover seal of the brake dual distribution valve (BDDV) was damaged and did not ensure efficient sealing. This proposed AD would require modifying the BDDV having certain part numbers; modifying the drain hose of the BDDV; checking for the presence of water, ice, and hydraulic fluid; and re-identifying the BDDV; and related investigative and corrective actions if necessary. We are proposing this AD to prevent damage to the BDDV, which could lead to water ingestion in the BDDV and freezing of the BDDV in flight, possibly resulting in loss of braking system function after landing.