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/25 Fan Blade Inspection/Revised Shroud Angle 8/94
All JT9D-7R4 Series engines.
1. Inspect fan blade leading edges in accordance with Pratt and Whitney Service Bulletin 72-255 Revision 5.
2. Incorporate fan blades featuring a revised shroud angle in accordance with Pratt and Whitney Service Bulletin 72-309 Revision 10.
Incorporation of Pratt and Whitney Service Bulletin 72-309 Rev 10 constitutes terminating action for the repetitive inspection per Requirement 1.
FAA AD 94-08-06 also refers.
1. Initially within 200 cycles in service from 21 July 1994, and thereafter, at intervals not to exceed 200 cycles.
2. No later than 21 July 1996.
This Directive is issued to prevent fan blade failures that have been attributed to a combination of high vibratory stresses and foreign object damage.