The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to PW JT9D series turbofan engines. We published the proposed AD in the Federal Register on November 2, 2005 (70 FR 66300). That action proposed to modify the JT9D series engines ALS sections of the manufacturer's manuals and an air carrier's approved continuous airworthiness maintenance program to incorporate additional inspection requirements. PW has added mandatory eddy current inspections (ECIs) for the web cooling holes in high pressure turbine (HPT) stage 1 disks installed in engine models JT9D- 7R4D, -7R4D1, -7R4E, and -7R4E1, and for web tie-rod holes in HPT stage 2 disks installed in JT9D-3A, -7, -7A, -7H, -7AH, -7F, -7J, -20, and - 20J engines. The mandatory inspections are needed to identify those critical rotating parts with conditions, which if allowed to continue in service, could result in uncontained failures.
Examining the AD Docket
You may examine the docket that contains the AD, any comments received, and any final disposition in person at the Docket Management Facility Docket Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647-5227) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives them.
Comments
We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.
Request To Delete ECIs for JT9D-59A, -70A, -7Q, and -7Q3 Engines
One commenter, Japan Airlines, requests that we delete the ECIs for JT9D-59A, -70A, -7Q, and -7Q3 engines from the table in the proposed AD compliance section. The commenter points out that the proposed AD preamble paragraph entitled "FAA's Determination and Requirements of the Proposed AD'' does not include ECIs for JT9D-59A, -70A, -7Q, and - 7Q3 engines.
We do not agree. We inadvertently omitted listing the requirement of ECI of the HPT stage 1 disk web cooling holes on JT9D-59A, -70A, - 7Q, and -7Q3 engines, under the proposed AD preamble paragraph entitled "FAA's Determination and Requirements of the Proposed AD''. The proposed AD compliance section and the compliance section in this AD, correctly list those engine models. We did not change the AD.
Request To Wait To Issue the AD
Japan Airlines requests that we wait to issue the AD until Pratt & Whitney provides the ECI procedure to the operators. The commenter states that the JT9D-7 Engine Manual Section 72-51-02, Inspection 05, has not been published yet.
We do not agree. Although the ECI procedure was not published in the JT9D-7 Engine Manual as of December 26, 2005 when the comment was sent, it was incorporated into the JT9D-7 Engine Manual on February 15, 2006. We do not need to wait to issue the AD.
Request To Revise Engine Manual
Japan Airlines requests that we recommend to Pratt & Whitney to revise the JT9D engine manual to remove the specific manufacturer's name of the ECI equipment required to perform ECIs, and to only list the technical specifications required to perform the ECIs. The commenter states that operators may not own the ECI equipment specified in the Pratt & Whitney JT9D engine manual, but may have similar equipment capable of performing the inspections.
We partially agree. This AD requires operators to revise the Airworthiness Limitations Section of the engine manual to include a mandatory opportunistic inspection. We do not intend for the AD to specify only one vendor's inspection equipment to accomplish the inspection. Nor do we intend that this AD change the way operators seek approval for alternative methods of inspections. We did not change the AD.
JT9D-3A Model Added to the Compliance Table
Upon review of the proposed AD, we discovered that the JT9D-3A model was inadvertently left out of the compliance table. We added the JT9D-3A model to the compliance table in the AD.
Update to the Costs of Compliance
Since we published the proposed AD on November 2, 2005, the number of engines affected and the hourly labor rate have changed. We updated this information in this AD preamble.
Correction to Compliance Table
Upon review of the proposed AD, we discovered that the compliance table needs correcting in the section for the -3A/7/7A/7AH/7F/7H/7J/20/ 20J engine models. "All HPT Stage 2 Disk Web Cooling Holes 71-51-02 Inspection-05'' is corrected to read "All HPT Stage 2 Disk Web Tie-rod Holes 72-51-02 Inspection-05''.
Conclusion
We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
We estimate that 504 JT9D series turbofan engines are installed on U.S.-registered airplanes and will be affected by this AD. We also estimate that 87 engines will require this inspection per year and about one work-hour per engine is needed to perform the actions, and that the average labor rate is $80 per work-hour. Since this is an added inspection requirement that will be part of the normal maintenance cycle, no additional parts costs are involved. Based on these figures, we estimate the total annual cost of the AD to U.S. operators to be $6,960.
Docket Number Change
We are transferring the docket for this AD to the Docket Management System as part of our on-going docket management consolidation efforts. The new Docket No. is FAA-2007-27023. The old Docket No. became the Directorate Identifier, which is 98-ANE-47-AD. This AD might get logged into the DMS docket, ahead of the previously collected documents from the old docket file, as we are in the process of sending those items to the DMS.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.
Regulatory Findings
We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a "significant regulatory action'' under Executive Order 12866;
(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and
(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary at the address listed under ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety,Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by removing Amendment 39-12719 (67 FR 19663, April 23, 2002), and by adding a new airworthiness directive, Amendment 39-14978, to read as follows: