Summary
We propose to adopt a new airworthiness directive (AD) for certain McDonnell Douglas Model DC-9-30, DC-9-40, and DC-9-50 series airplanes. This proposed AD would require inspecting to determine the part numbers of the forward and aft auxiliary tank fuel boost and transfer pump conduit/conduit assembly and conduit assembly electrical connector, as applicable, and corrective actions if necessary. This proposed AD results from fuel system reviews conducted by the manufacturer. We are proposing this AD to detect and correct the potential for an arc/spark condition to occur within the fuel boost or transfer pump conduit assembly connectors and propagate into the forward and aft auxiliary fuel tanks, which could result in a fire or explosion.