COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
General Electric Turbine Engines - CF6 Series
AD/CF6/9 High Pressure Turbine Impeller Spacer Eddy Current Inspection
Applicability: CF6-50/-45 Series.
2/88 TX
Requirement: Eddy current inspection of impeller spacers in accordance with General Electric Service Bulletin SB72-906 and their removal from service.
Compliance: In accordance with paras (a), (b), (c) and (d) of FAA AD 87-23-06 General Electric: Amendment 39-5746, effective from 1 December 1987.
Background: Fatigue cracks attributed to high stress low cycle fatigue (LCF) can originate in bolt holes on certain GE CF6-50 and -45 impeller spacers. These components have been subject to special inspection in the past but now must be subject to a particular eddy current inspection process specified in GE Service Bulletin 72-906. The FAA has imposed more stringent initial and repetitive inspection periods on the components than those specified by GE, and it specifies requirements for their removal from service. This AD supersedes AD/CF6/4.