COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Pratt and Whitney Turbine Engines - JT9D Series AD/JT9D/29 Amdt 2 Turbine Exhaust Case 2/98 Applicability: Pratt and Whitney JT9D series engines. Requirement: 1. Install an improved turbine exhaust case in accordance with the technical requirement of FAA AD 96-25-10, or 2. Install an improved turbine exhaust case in accordance with Pratt and Whitney Service Bulletin JT9D-7R4-72-534 Revision 1. Note: Pratt and Whitney Service Bulletin JT9D-7R4-72-534 Revision 1, Paragraph 1.D advises compliance with SB JT9D-7R4-72-534 has been approved by the FAA as an alternative means of compliance for FAA AD 96-25-10. Compliance: Unless previously accomplished, as detailed in the requirement document with an effective date of 30 January 1998. This amendment becomes effective on 29 January 1998. Background: This Directive is issued on advice from the FAA of a significant number of uncontained engines failures since 1972. The improved turbine exhaust case features enhanced debris containment in the event of an engine failure. This amendment adds an alternative means of compliance. Amendment 1 corrected the FAA reference in the requirement statement and became effective on 19 June 1997. Amendment 1 of this airworthiness directive became effective on 19 June 1997. The original issue of this airworthiness directive became effective on 22 May 1997.