Airworthiness Directives; Avcraft Dornier Model 328-100 and -300 Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Avcraft Dornier Model 328-100 and -300 airplanes. This AD requires a pressure test and detailed inspection of each fuselage drain line to determine if there is a blockage, and related investigative/ corrective actions if necessary. This AD is prompted by a report of leakage at one of the drain lines in the fuselage. We are issuing this AD to prevent blockage within the drain lines, causing fluids to collect. These fluids may freeze and expand, damaging the drain lines, and allowing fuel to leak into the cabin and fuel vapors to come into contact with ignition sources, which could result in consequent fire in the cabin.