Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This AD was prompted by chafing on high pressure fuel lines due to improper installation of an expandable pin on the lower cowl assembly. This AD requires installing spring clips and repositioning the lanyard attachment points at the forward end and the forward firefloor of the lower cowl. We are issuing this AD to prevent chafing of the high pressure fuel lines, which if not corrected, could cause fuel leakage in a fire zone.