Airworthiness Directive · Amendment 39-14256 · General Electric Company CF34-3A1 Turbofan Engines
General Electric Company CF34-3A1 Turbofan Engines
This AD applies to General Electric CF34-3A1 turbofan engines installed on Bombardier series Regional Jet Model CL-600-2B19 (Regional Jet Series 100 and 440) airplanes with one or more of the HPT rotating components installed, listed in the following Table 1:
| Part No. | Nomenclature |
|---|---|
| 6078T90P01 | Seal, Balance Piston Air. |
| 6017T00P05 | Shaft, HPT Rotor. |
| 4027T15P03 | Plate, Stage 1 Front Cooling. |
| 6078T93P01 | Disk, Stage 1 Turbine. |
| 6078T93P02 | Disk, Stage 1 Turbine. |
| 5041T70P03 | Plate, Stage 1 Aft Cooling. |
| 5023T97P03 | Plate, Stage 2 Rear Cooling. |
| 6078T94P01 | Disk, Stage 2 Turbine. |
| 6078T94P02 | Disk, Stage 2 Turbine. |
| 5042T29P02 | Plate, Stage 2 Front Cooling. |
| 5041T67P02 | Coupling, Outer Torque. |
| 5079T02P01 | Coupling, Inner Torque. |
The FAA is adopting a new airworthiness directive (AD) for General Electric Company (GE) CF34-3A1 turbofan engines installed on Bombardier series Regional Jets with certain high pressure turbine (HPT) rotating components installed. This AD requires removal from service of certain HPT components prior to the parts exceeding their designated life limits. This AD results from the discovery that the manufacturer removed certain part numbers of HPT rotating components from the Life Limits section of the CF34 Engine Manual, SEI-756. The effect of this manual change was the removal of life limits from certain components that are eligible for installation in GE CF34-3A1 engines. We are issuing this AD to impose life limits on these HPT rotating components to prevent low cycle fatigue (LCF) cracking and failure of those components, which could result in uncontained engine failure and damage to the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.
(f) Remove from service the HPT rotating components listed in Table 1 of this AD before exceeding the life limit of 6,000 cycles-since-new.
