Summary
This document revises an earlier proposed airworthiness directive (AD), applicable to certain Boeing Model 727, 737-100, 737-200, and 737-200C series airplanes. That proposed AD would have required a one-time inspection to determine the part number of hydraulic accumulators installed in various areas of the airplane, and follow-on corrective actions if necessary. This new action revises the proposed rule by adding an inspection of an additional area of the airplane, and follow-on corrective actions if necessary. This new action also clarifies what actions are necessary for accumulators with certain part numbers. This action is necessary to prevent high-velocity separation of a barrel, piston, or end cap from a hydraulic accumulator. Such separation could result in injury to personnel in the accumulator area; loss of cabin pressurization; loss of affected hydraulic systems; or damage to plumbing, electrical installations, or structural members. This action is intended to address the identified unsafe condition.