Summary
This action withdraws a notice of proposed rulemaking (NPRM) that proposed a new airworthiness directive (AD), applicable to all Lockheed Model L-1011-385 series airplanes. That action would have required repetitive leak tests of the lavatory drain systems and repair, if necessary; installation of a lever lock cap, vacuum breaker check valve or flush/fill line ball valve on the flush/fill line; periodic seal changes; and replacement of "donut'' type waste drain valves installed in the waste drain system. Since the issuance of the NPRM, the Federal Aviation Administration (FAA) has reviewed existing data and determined that, for airplanes without a history of engine damage resulting from "blue ice,'' such as Lockheed Model L-1011-385 series airplanes, the hazard of "blue ice'' to persons and property may be more appropriately addressed through means other than AD action. Accordingly, the proposed rule is withdrawn.