Vincent Chandler

1/ NPRM as written implies the grace period for FPI or ECI apply to the repetitive USI frequency, however per SB’s 72-0608 and 72-0615, the grace periods “affect the inspection start but not the inspection interval” Amend (f)(1)(i) and (ii), and (f)(2) initial inspection threshold to include grace periods; ... in IAE SB No. V2500-ENG-72-0615, Revision 3, dated September 20, 2011, at the later of; (1) Before accumulating 12,500 CSN or within 500 cycles from the effective date of this AD, whichever occurs later, not to exceed 13,700 CSN; or (2) Within 2,500 cycles since FPI, or within 13,000 cycles since ECI, in accordance with paragraph (g)(2) of this AD, whichever occurs latest. Amend (h) to read; Perform repetitive USI’s of the HPC stage 3 to 8 drum for cracks IAW paragraphs (f)(1) or (f)(2) of this AD within every 750 cycles-since-last USI. (end) 2/ IAE Shop meeting notes on HPC 3-8 Drum Fleet management indicate that EM task 72-41-11-110-001 (to be revised by EC09VR896B) will be the only way to clean the silver residue from the drum (and further that it is IAE’s intention to delete SB 72-0601) Amend (g)(ii) to read;* Remove the silver residue from the HPC stage 3 to 8 drum using engine manual task 72-41-11-110-001. Drums cleaned before the effective date of this AD using the IAE SB No. V2500-ENG-72-0601, Revision 2 (or earlier??) satisfy this requirement. *IAE to confirm when revised EM task will be published, and if 72-0601 is to be deleted (assuming it is not incorporated by reference**) 3/ Typo in Para (i) ‘... paragraphs (h)(1) and (h)(2) of this AD...’ should read ‘... paragraphs (i)(1) and (i)(2) of this AD...’ 4/ Typo in Para (k)(4) V2500-ENG-72-615 should read V2500-ENG-72-0615 5/ AD Compliance actions (f) and (g) require actions to be performed in accordance with specified revisions of IAE SB's. The AD does not have a Material Incorporated by Reference section. Shouldn’t these SB's be incorporated by reference?