Airworthiness Directive · Amendment 39-13914 · GE Aircraft Engines (GE) CF34-3A, CF34-3A2, CF34-1A, CF34-3A1, CF34-3B, and CF34-3B1 Series Turbofan Engines
GE Aircraft Engines (GE) CF34-3A, CF34-3A2, CF34-1A, CF34-3A1, CF34-3B, and CF34-3B1 Series Turbofan Engines
This AD applies to GE CF34-3A, CF34-3A2, CF34-1A, CF34-3A1, CF34-3B, and CF34-3B1 series turbofan engines with high pressure compressor (HPC) forward spool, part number (P/N) 6078T56P03 or 6078T56P04, installed. These engines are installed on, but not limited to, Bombardier series Business Jet Model CL-600-2A12 (CL-601), Bombardier series Business Jet Model CL-600-2B16 (CL-601-3A, CL-601-3R, and CL-604), and Bombardier series Regional Jet Model CL-600-2B19 (Regional Jet Series 100 and 440) airplanes.
The FAA is adopting a new airworthiness directive (AD) for GE CF34-3A, CF34-3A2, CF34-1A, CF34-3A1, CF34-3B, and CF34-3B1 series turbofan engines. This AD requires removal from service of certain high pressure compressor (HPC) forward spools, at the first piece-part level exposure after 6,000 cycles since new (CSN); but not later than 20,000 CSN for CF34-3B engines, and not later than 22,000 CSN for CF34-3A, CF34-3A2, CF34-1A, CF34-3A1, and CF34-3B1 engines. This AD results from an updated low-cycle fatigue (LCF) analysis performed on certain HPC forward spools. We are issuing this AD to prevent LCF cracks and failure of the HPC forward spool, which could result in an 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.
For CF34-3B engines, remove from service HPC forward spools, P/Ns 6078T56P03 and 6078T56P04 at the first piece-part exposure after 6,000 cycles-since-new (CSN), but no later than 20,000 CSN.
(g) For CF34-3A, CF34-3A2, CF34-1A, CF34-3A1, and CF34-3B1 engines, remove from service HPC forward spools, P/Ns 6078T56P03 and 6078T56P04 at the first piece-part exposure after 6,000 CSN, but no later than 22,000 CSN.
(h) After the effective date of this AD:
(1) Do not install any HPC forward spool, P/N 6078T56P03.
(2) Do not install any HPC forward spool, P/N 6078T56P04, with more than 0 CSN.
(i) For the purpose of this AD, the definition of piece-part exposure for the HPC forward spool is when the spool is completely disassembled.
