81-19-08 GENERAL ELECTRIC: Amendment 39-4219. Applies to all General Electric Model CF6-6 series turbofan engines installed in McDonnell Douglas DC10-10 aircraft containing low pressure turbine rotor stage 2 disks, P/Ns 9690M77P03, 9690M77P04, 9690M77P09, 9690M77P11, and 9690M77P13.
Compliance required as indicated.
To prevent possible low cycle fatigue failure of these disks, the life limits have been reduced below the figures currently approved. Remove from service low pressure turbine rotor stage 2 disks prior to reaching the revised life limits listed below or within the next 25 cycles in service after the effective date of this AD, whichever comes later.
Disk Part Number
Previous Life Limit/Cycles
Revised Life Limit/Cycles
9690M77P03
27,000
11,500
9690M77P04
27,000
11,500
9690M77P09
27,000
11,500
9690M77P11
27,000
11,500
Serial Numbers
MP0A0727 through MP0A2215
9690M77P11
27,000
9,300
All other serial numbered disks9690M77P13
27,000
10,000
NOTE: General Electric CF6-6 Service Bulletin 72-786 pertains to this subject.
This amendment becomes effective on September 21, 1981.