Document ID: chunk:federal_register_of_legislation:F2007L01377:body:0:p1
Version: federal_register_of_legislation:F2007L01377
Segment Type: other
Provision Reference: 
Character Range: 0–3045

AIRWORTHINESS DIRECTIVE
On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CT7/12 and issues the following AD under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

General Electric Turbine Engines - CT7 Series
AD/CT7/12 Amdt 1  Stage 2 Turbine Aft Cooling Plate  6/2007

Applicability:  General Electric Company (GE) CT7-5A2/-5A3/-7A/-7A1/-9B/-9B1/-9B2/-9C/-9C3/
                -9D/-9D2 turboprop engines with stage 2 turbine aft cooling plates, part number (P/N) 6064T07P01, 6064T07P02, 6064T07P05, or 6068T36P01 installed.

                Note 1:  These engines are installed on, but not limited to, Construcciones Aeronauticas, SA CN-235 series and SAAB Aircraft AB SF340 series airplanes.
Requirement:       Onetime Eddy Current Inspection (ECI)

                   1. Perform a onetime ECI of the stage 2 turbine aft cooling plates P/N 6064T07P01, 6064T07P02, 6064T07P05, or 6068T36P01, that are listed by serial number in Section 4, Appendix A, of GE Alert Service Bulletin (ASB) No. CT7-TP S/B
                   72-A0464, Revision 4, dated 12 December 2005, and that will be returned to service.  Use 3.B.(1) through 3.B.(3) of GE ASB No. CT7-TP S/B 72-A0464, Revision 4 or later FAA approved revisions to perform the inspection.

                   2. For stage 2 turbine aft cooling plates that do not pass the Return to Service Criteria, do either of the following:

                     a. Replace the stage 2 turbine aft cooling plate with a new cooling plate that has a serial number that is not listed in Section 4, Appendix A, of GE ASB
                     No. CT7-TP S/B 72-A0464, Revision 4, or

                     b. Replace the stage 2 turbine aft cooling plate with a cooling plate that meets the acceptance criteria of 3.B.(1) through 3.B.(3) of GE ASB No. CT7-TP S/B 72-A0464, Revision 4.

                   3. After the effective date of this AD, do not install any stage 2 turbine aft cooling plates with serial numbers identified in Section 4, Appendix A, without inspecting the cooling plate as specified in 3.B.(1) through 3.B.(3) of GE ASB No. CT7-TP S/B 72- A0464 Revision 4.

                Previous Credit

                Eddy current inspections of the stage 2 turbine aft cooling plate boltholes done before the effective date of this AD that use GE ASB No. CT7-TP S/B
                72-A0464, dated 25 February 2003; or Revision 1, dated 12 March 2003; or Revision 2, dated 9 May 2003; or Revision 3, dated 23