Summary
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Boeing Model 767-200, -300, and -300F series airplanes. The existing AD currently requires an inspection of visually accessible areas for indications of overheating of the heater tape attached to the potable water fill and drain lines in the forward and aft cargo compartments, exposed foam insulation or missing or damaged protective tape around the potable water fill and drain lines, and debris or contaminants on or near the potable water fill and drain lines. That AD also requires corrective action, as necessary. This proposed AD would require repetitive inspections of the forward and aft cargo compartments, as applicable, for discrepancies of the potable water supply and gray water drain lines; and applicable corrective actions if necessary. This proposed AD also would require replacing the heater tapes on the potable water supply and gray water drain lines of the forward and aft cargo compartments, as applicable, with new ribbon heaters, which would end the repetitive inspections. This proposed AD results from a report of a fire in the aft cargo compartment. We are proposing this AD to prevent overheating of the heater tape on potable water fill and drain lines, which may ignite accumulated debris or contaminants on or near the potable water fill and drain lines, resulting in a fire in the airplane.