Airworthiness Directive · Amendment 39-14566 · General Electric Company Aircraft Engines (GEAE) CT7-8A Turboshaft Engines
General Electric Company Aircraft Engines (GEAE) CT7-8A Turboshaft Engines
Superseded. A later AD replaced this one: AD 2008-26-02. Comply with the one in force.
This AD applies to General Electric Company Aircraft Engines (GEAE) CT7-8A serial numbers (SNs) 947201 through 947204, 947209 through 947235, 947238 through 9472268, 947273 through 947281, and 947283 though 947285. These engines are installed on, but not limited to, Sikorsky S92 helicopters.
This document publishes in the Federal Register an amendment adopting emergency airworthiness directive (EAD) 2006-06-51 that we sent previously to all known U.S. owners and operators of GEAE CT7-8A turboshaft engines installed on Sikorsky S92 helicopters. This AD requires initial and repetitive inspections of the electrical chip detectors for the No. 3 bearing. This AD results from two failures of the No. 3 bearing in GEAE CT7-8A engines. We are issuing this AD to prevent failures of the No. 3 bearings and possible dual in-flight shutdowns of the engines.
You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.
Within 25 hours time-in-service after the effective date of this AD, do the following:
(1) Remove the electrical chip detector assembly.
(2) If the chip detector assembly contains any bearing material, replace the engine.
(3) Stagger the inspection intervals so the chip detectors on both engines on the same helicopter are not inspected at the same time.
Thereafter, within 25 hours time-since-last inspection, perform the inspection specified in paragraph (f)(1) through (f)(3) of this AD.
