AD FAA-2018-0297

We propose to adopt a new airworthiness directive (AD) for certain Airbus Model A319 series airplanes; Model A320-211, -212, -214, -231, -232, and -233 airplanes; and Model A321-111, -112, -131, -211, - 212, -213, -231, and -232 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 identifying the BDDV part number installed on the airplane, and modifying or replacing BDDVs having certain part numbers. We are proposing this AD to address the unsafe condition on these products.