Airworthiness Directives; Lockheed Martin Models L-1011 Airplanes and Rolls-Royce plc RB211 Series Turbofan Engines

This amendment supersedes an existing airworthiness directive (AD) that is applicable to Lockheed Martin L-1011-385 series airplanes. That AD currently requires modifications of the engine turbine cooling air overheat monitoring panel at the flight engineer/second officer's console, pilot's caution and warning light panel on the main instrument panel, and the installation of a high speed gearbox (HSGB) overheat detector system into the monitoring system for the engine turbine air temperature. This amendment requires the same modifications. In addition, this amendment adds Lockheed Martin L-1011-385 series airplanes with RB211-22B-02 series engines to the applicability, requires installation of a revised engine front bearing housing assembly, installation of a revised speed probe loom electrical support assembly, and installation of a low pressure (LP) compressor shaft extreme axial movement detector system. Also, this amendment requires additional modifications to the engine turbine cooling air overheat monitoring panel at the flight engineer/second officer's console, pilot's caution and warning light panel on the main instrument panel. The actions specified by this AD are intended to prevent undetected fires originating within the HSGB from breaching the HSGB case, which could result in engine damage and increased difficulty in extinguishing a fire, and to prevent undetected LP compressor shaft location bearing failure, which could result in LP compressor and turbine shaft assembly failure, turbine overspeed, and possible uncontained engine failure.