Airworthiness Directive · Amendment 39-18445 · General Electric Company Turbofan Engines
General Electric Company Turbofan Engines
This AD applies to all General Electric Company (GE) CF6-80E1 turbofan engines with rotating compressor discharge pressure (CDP) seals, part number (P/N) 1669M73P02, installed.
We are adopting a new airworthiness directive (AD) for all General Electric Company (GE) CF6-80E1 turbofan engines with rotating compressor discharge pressure (CDP) seal, part number (P/N) 1669M73P02, installed. This AD was prompted by reports from the manufacturer of cracks in the teeth of two rotating CDP seals found during engine shop visits. This AD requires stripping of the coating, inspecting, and recoating the teeth of the affected rotating CDP seals. We are issuing this AD to prevent cracking of the CDP seal teeth, uncontained part release, damage to the engine, and damage to the airplane.
(1) Comply with this AD within the compliance times specified, unless already done.
(2) Strip coating, inspect, and recoat the teeth of the rotating CDP seal, P/N 1669M73P02. Use paragraph 3.C.(2) of GE Service Bulletin (SB) CF6-80E1 S/B 72-0529, Revision 01, dated August 21, 2015 to do the strip coating, inspecting, and recoating, as follows:
(i) For engines that have had stationary CDP seal, P/N 1347M28G02, replaced or stationary CDP seal honeycomb repaired; strip coating, inspect, and recoat the teeth of the rotating CDP seal at the next engine shop visit.
(ii) For engines that have not had stationary CDP seal, P/N 1347M28G02, replaced or stationary CDP seal honeycomb repaired; strip coating, inspect, and recoat the teeth of the rotating CDP seal at the next part exposure of the rotating CDP seal.
After the effective date of this AD, do not install any rotating CDP seal, P/N 1669M73P02, that has not had its seal teeth recoated using procedures specified in ESM 72-31-10, REPAIR 002 of GE CF6-80E1 (GEK99376) Engine Manual, Revision 42, dated March 15, 2014, into any engine.
(1) For the purpose of this AD, exposure of the rotating CDP seal is defined as removal of the compressor rear frame from the high-pressure compressor (HPC) module.
(2) For the purpose of this AD, an engine shop visit is defined as the induction of an engine into the shop for maintenance involving the separation of any major mating engine flanges, except that the separation of engine flanges solely for the following purposes is not considered a shop visit:
(i) Transportation without subsequent engine maintenance.
(ii) Removing the turbine rear frame (TRF) for repair of TRF cracking.
(iii) Removing the top or bottom HPC case, or both, for HPC airfoil maintenance.
(iv) Removing only the accessory gearbox and/or transfer gearbox.
(v) Replacing the high-pressure turbine (HPT) stage 1 blades per CF6-80E1 SB 72-0504 “Quick-Turn Workscope Procedure to Replace CF6-80E1 Stage 1 HPT Blades”.
(3) For the purpose of this AD, a stationary CDP seal is replaced if at any previous shop visit, the seal has been removed and a different seal is installed.
You may take credit for the actions that are required by paragraph (e) of this AD if the actions were performed before the effective date of this AD using the procedures in ESM 72-31-10, REPAIR 002 of the GE CF6-80E1 (GEK99376) Engine Manual, Revision 42, dated March 15, 2014, or earlier versions.
