AD 2006-07-26

The FAA is adopting a new airworthiness directive (AD) for all Aerospatiale Model ATR42 airplanes. This AD requires one-time inspections to detect discrepancies (e.g., cracking, loose/sheared fasteners, distortion) of the upper skin and rib feet of the outer wing boxes, and repair if necessary. This AD results from a report of cracking on the upper skin and ribs of the outer wing box on an in- service airplane. We are issuing this AD to detect and correct these discrepancies, which could result in reduced structural integrity of the airplane.

Final rule.

2006-07-26 Aerospatiale: Amendment 39-14553. Docket No. FAA-2006- 23816; Directorate Identifier 2005-NM-247-AD.

Effective Date

(a) This AD becomes effective May 16, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all Aerospatiale Model ATR42-200, -300, - 320, and -500 airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from a report of cracking on the upper skin and ribs of the outer wing box on an in-service airplane. We are issuing this AD to detect and correct discrepancies (e.g., cracking, loose/sheared fasteners, distortion) of the upper skin and rib feet of the outer wing boxes, which could result in reduced structural integrity of the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

External Inspection and Repair

(f) Before the accumulation of 4,000 total flight cycles, or within 3 months after the effective date of this AD, whichever is later: Do an external detailed inspection for discrepancies of the upper skin panels of the outer wing box on the left and right wing, from rib 24 to rib 29. Do the inspection in accordance with Part A of the Accomplishment Instructions of Avions de Transport Regional Service Bulletin ATR42-57-0064, dated December 16, 2004.

(1) If any discrepancy is found: Before further flight, do the actions in paragraphs (f)(1)(i) and (f)(1)(ii) of this AD.
(i) Repair using a method approved by either the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or the Direction G[eacute]n[eacute]rale de l'Aviation Civile (DGAC) (or its delegated agent).

(ii) Do the internal inspection in accordance with paragraph (g) of this AD.

(2) If no discrepancy is found: Within 4 months after doing the external detailed inspection, do the internal inspection in accordance with paragraph(g) of this AD.

Note 1: For the purposes of this AD, a detailed inspection is: ``An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.''

Internal Inspection and Repair

(g) At the applicable time specified in paragraph (f)(1)(ii) or (f)(2) of this AD: Inspect for discrepancies of the rib feet from rib 24 to rib 29 using one of the inspection methods specified in paragraph (g)(1) or (g)(2) of this AD. Do the inspection in accordance with Part B of the Accomplishment Instructions of Avions de Transport Regional Service Bulletin ATR42-57-0064, dated December 16, 2004. If any discrepancy is found during any inspection required by this paragraph: Before further flight,repair using a method approved by either the Manager, International Branch, ANM-116, FAA, or the DGAC (or its delegated agent).

(1) A borescopic inspection through access doors.

(2) A detailed inspection after removing the leading edge of the wing.

No Reporting

(h) Although Avions de Transport Regional Service Bulletin ATR42-57-0064, dated December 16, 2004, specifies to submit certain information to the manufacturer, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, International Branch, ANM-116, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with Sec. 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(j) French airworthiness directive F-2004-191, dated December 22, 2004, also addresses the subject of this AD.

Material Incorporated by Reference

(k) You must use Avions de Transport Regional Service Bulletin ATR42-57-0064, dated December 16, 2004, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Examining the Docket

You may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section.

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to all Aerospatiale Model ATR42 airplanes. That NPRM was published in the Federal Register on February 8, 2006 (71 FR 6413). That NPRM proposed to require one-time inspections to detect discrepancies (e.g., cracking, loose/sheared fasteners, distortion) of the upper skin and rib feet of the outer wing boxes, and repair if necessary.

Comments

We provided the public the opportunity to participate in the development of this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Clarification of Reporting

In the preamble of the NPRM we stated that although ``the French airworthiness directive and the service bulletin specify to submit certain information to the manufacturer, this proposed AD does not include that requirement.'' However, we did not include this exception in the body of the NPRM. We have added paragraph (h) to clarify that reporting is not required.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD with the change described previously. We have determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

This AD will affect about 14 airplanes of U.S. registry. The actions will take about 6 work hours per airplane if the internal borescopic inspectionmethod is chosen, and about 44 work hours per airplane if the internal detailed inspection method (with the leading edge removed) is chosen. Both estimates include the time necessary for the external detailed inspection. The average labor rate is $65 per work hour. Based on these figures, the estimated cost of the AD for U.S. operators is between $5,460 and $40,040, or either $390 or $2,860 per airplane.

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 forpractices, 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 regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

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 Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):