Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on May 8, 2009 (74 FR 21561), and proposed to supersede AD 2003-14-07, Amendment 39-13226 (68 FR 41903, July 16, 2003). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI (two different MCAI) states:
FOCA AD HB 2002-271 was issued because the Nose Landing Gear (NLG) Right Hand (RH) upper drag link, Part Number (P/N) 532.20.12.140 was found broken on some aircraft due to fatigue cracking, and therefore a life limit of 4,000 landings was introduced.
Recent investigation of a new occurrence revealed that the replacement part NLG RH upper drag link P/N 532.20.12.289 also suffered fatigue cracking, however on a different location.
Complete failure of the NLG RH upper drag link could result in NLG collapse during landing. To address that condition, this AD is issued to mandate the implementation of the latest revision of the PC-12 Aircraft Maintenance Manual (AMM) chapter 4--airworthiness limitations section--by establishing repetitive inspections for the NLG RH upper drag links P/N 532.20.12.140 and P/N 532.20.12.289.
and
This Airworthiness Directive (AD) is prompted by reports of several in-service cracked torque tubes. A reduced wall thickness produced during the manufacturing process has been determined to be the initial cause.
Additionally, all the involved torque tubes have been found to show fatigue cracking problems.
Such a condition, if left uncorrected, could lead to failure of the torque tube and result in loss of the steering control on ground and consequent unsafe condition.
For the reason described above, this new AD mandates the replacement of certain torque tubes by new ones of an improved design and the latest revision of chapter 4 `limitations' of the PC- 12 Aircraft Maintenance Manual (AMM) which introduces the new life limit for torque tubes with Part Number (P/N) 532.50.12.047.
We reviewed the available data, including the comment received, and determined that air safety and the public interest require adopting the AD as proposed.
Comments
We gave the public the opportunity to participate in developing this AD. We considered the comment received.
Comment Issue: Require Using Limitations Document in Latest Maintenance
Manual Revision
Tim Kitzman states that document 12-A-04-00-00-00A-000T-A, dated January 28, 2009, has been incorporated into the latest revision of the aircraft maintenance manual. He requests that we update the AD to require incorporating the data module found in PC-12 AMM, Document No. 02049, Rev 19, dated March 1, 2009.
We disagree with the commenter. Structural and Component Limitations--Airworthiness Limitations, document 12-A-04-00-00-00A- 000T-A, dated January 28, 2009, contains the required limitations information for this AD. We are aware Pilatus periodically updates their aircraft maintenance manuals (both electronic and paper versions), and the manuals contain the limitations section referenced in this AD. We encourage owners/operators to keep their maintenance manuals up-to-date. However, paragraph 145.c.(2) of the FAA Airworthiness Directives Manual FAA-IR-M-8040.1B, dated May 28, 2008, states:
Only the version given to the OFR (Office of the Federal Register) for IBR (incorporation by reference) is the legally enforceable one. Later revised service bulletin pages, for instance, would constitute a change to the document and an "alternative method of compliance'' that has not been subject to public notice and comment.
We use the AD process to mandate changes to the limitations section and we can not mandate future revisions. If the document containing the limitations section is updated and an owner/operator wants to incorporate the latest version of the document (including the limitations section) into their maintenance program, they can request an alternative method of compliance (AMOC) following the procedures in paragraph (h)(1) of this AD. You may get a copy of the FAA Airworthiness Directives Manual on the Internet at http://rgl.faa.gov/ Regulatory_and_Guidance_Library/rgOrders.nsf/Frameset?OpenPage.
We are not changing the final rule AD action based on this comment.
Conclusion
We reviewed the available data, including the comment received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We determined that these changes will not increase the economic burden on any operator or increase the scope of the AD.
Differences Between This AD and the MCAI or Service Information
We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in theMCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.
We might also have required different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a NOTE within the AD.
Costs of Compliance
We estimate that this AD will affect 540 products of U.S. registry. We also estimate that it will take about 3.5 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Required parts will cost about $300 per product. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $313,200, or $580 per product.
In addition, we estimate that any necessary follow-on actions would take about 6 work-hours and require parts costing $4,000, for a cost of $4,480 per product. We have no way of determining the number of products that may need these actions.
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 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 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 regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD Docket.
Examining the AD Docket
You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m.,Monday through Friday, except Federal holidays. The AD docket contains the NPRM, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone (800) 647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the FAA 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 39-13226 (68 FR 41903, July 16, 2003) and adding the following new AD: