AD 97-26-11

This amendment adopts a new airworthiness directive (AD), applicable to certain Aerospatiale Model ATR42-200, -300, and -320 series airplanes, that requires an inspection to detect corrosion of the rear spars of the wings, and corrective actions, if necessary. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to detect and correct possible corrosion on the rear spars of the wings, which could result in reduced structural integrity of the wings.

Final rule.

97-26-11 AEROSPATIALE: Amendment 39-10254. Docket 95-NM-140-AD.

Applicability: Model ATR42-200, -300, and -320 series airplanes, as listed in Aerospatiale Service Bulletin ATR42-57-0044, dated May 30, 1995, or Revision 1, dated June 28, 1995; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specificproposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct corrosion on the rear spars of the wings, which could result in reduced structural integrity of the wing, accomplish the following:

(a) Within 60 days after the effective date of this AD, perform a one-time detailed visual inspection to detect corrosion of the rear spars of the wings, in accordance with Aerospatiale Service Bulletin ATR42-57-0044, dated May 30, 1995, or Revision 1, dated June 28, 1995.

(1) If no corrosion is detected, prior to further flight, apply a protective compound to the areas specified in the service bulletin, in accordance with the service bulletin.

(2) If any corrosion is detected, prior to further flight, repair it in accordance with a method approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate.

(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

(c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

(d) The actions shall be done in accordance with Aerospatiale Service Bulletin ATR42-57-0044, dated May 30, 1995; or Aerospatiale Service Bulletin ATR42-57-0044, Revision 1, dated June 28, 1995; which contain the specified effective pages.

Service Bulletin
Referenced and Date

Page Number
Revision Level
Shown on Page
Date
Shown on Page
ATR42-57-0044,
May 30, 1995
1-17
Original
May 30, 1995
ATR42-57-0044,
Revision 1,
June 28, 1995
1, 4, 6-8, 15-16

2, 3, 5, 9-14, 17
1

Original
June 28, 1995

May 30, 1995

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

NOTE 3: The subject of this AD is addressed in French airworthiness directive 95-127- 063(B), dated August 2, 1995.

(e) This amendment becomes effective on January 23, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Aerospatiale Model ATR42-200, -300, -320 series airplanes was published in the Federal Register on October 01, 1997 (62 FR 51388). That action proposed to require an inspection to detect corrosion of the rear spars of the wings, and corrective actions, if necessary.

Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received.

Request to Withdraw the Proposal
The Direction G n rale de l'Aviation Civile (DGAC) has no technical objection to the proposal, but requests that the FAA withdraw it because French airworthiness directive 95-127-062(B) was issued against a target set of airplanes, and was intended to evaluate and quantify the problems with corrosion in the area of the wing spars. The results of the inspection enabled the manufacturer to define long term actions and revise the airplane maintenance program (known as the Maintenance Review Board or MRB), to include the necessary inspections and corrective actions. The commenter further states that the revised MRB has been implemented by U.S. operators, and that an AD mandating these same actions is not required.

The FAA does not concur with the commenter s request to withdraw the proposal. The MRB document referenced by the commenter is not mandatory for U.S. operators. Therefore, the issuance of this AD is the only means available to the FAA to require changes in the maintenance of the airplane which are related to an unsafe condition. The"Compliance" provision of this AD states that compliance is required as indicated,"unless accomplished previously." Therefore, if an operator has adopted and complied with MRB provisions that describe the inspection required by this AD, it may take credit for prior accomplishment of those actions.

Conclusion
After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact
The FAA estimates that 16 Model ATR42-200, -300, and -320 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 24 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $23,040, or $1,440 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact
The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption"ADDRESSES."

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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.
39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: