Airworthiness Directives; Airbus Model A319, A320, and A321 Series Airplanes

[Federal Register Volume 63, Number 225 (Monday, November 23, 1998)] [Proposed Rules] [Pages 64654-64655] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 98-31177]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-284-AD] RIN 2120-AA64

Airworthiness Directives; Airbus Model A319, A320, and A321 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Airbus Model A319, A320, and A321 series airplanes. This proposal would require a one-time inspection of the forward engine mount assembly of the left and right engines to verify that the part number on each assembly is correct; re- identification of the forward engine mount assembly; and follow-on actions, if necessary. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent structural failure of the secondary load path of the forward engine mount, which, if combined with failure of the primary load path, could result in separation of the engine from the airplane.

DATES: Comments must be received by December 23, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-M-284-D, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. The service information referenced in the proposed rule may be obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 98-NM-284-AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-284-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Direction Generale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, notified the FAA that an unsafe condition may exist on certain Airbus Model A319, A320, and A321 series airplanes. The DGAC advises that, during modification of the forward engine mount assembly of the left and right engines to meet increased thrust load specifications, certain engine mount assemblies may not have been modified properly. Improper modification of these assemblies could cause the secondary load path of the forward engine mount to be unable to sustain required loads, resulting in structural failure, which, if combined with failure of the primary load path, could result in separation of the engine from the airplane.

Explanation of Relevant Service Information

The manufacturer has issued Airbus Service Bulletin A320-71-1021, Revision 01, dated June 10, 1998, which describes procedures for a one- time visual inspection of the forward engine mount assembly of the left and right engines to verify that the part number (P/N) on each assembly is correct; re-identification of the forward engine mount assembly; and follow-on actions, if necessary. If the P/N of the forward engine mount is incorrect, the follow-on actions involve removal of the engine, visual inspection to detect any crack or failure of the thrust links on the forward engine mount assembly, modification of the engine mount if no crack or failure is detected, or replacement of the existing thrust link with a new thrust link and modification of the engine mount if any crack or failure is detected. Accomplishment of the actions specified in the Airbus service bulletin is intended to adequately address the identified unsafe condition. The Airbus service bulletin references V2500 International Aero Engines Service Bulletin V2500-NAC-71-0135, Revision 1, dated March 5, 1998, as an additional source of service information. The DGAC classified the Airbus service bulletin as mandatory and issued French airworthiness directive 98-293-118(B) dated July 29, 1998, in order to assure the continued airworthiness of these airplanes in France.

FAA's Conclusions

These airplane models are manufactured in France and are type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the DGAC has kept the FAA informed of the situation described above. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

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Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would require accomplishment of the actions specified in the Airbus service bulletin described previously.

Cost Impact

The FAA estimates that 73 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 70 work hours per airplane to accomplish the proposed inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the inspection proposed by this AD on U.S. operators is estimated to be $306,600, or $4,200 per airplane. The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed 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 proposed herein would 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 proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Airbus Industrie: Docket 98-NM-284-AD.

Applicability: Model A319-131 and -132, A320-232 and -233, and A321-131 series airplanes; except those on which Airbus Modification 27020 has been accomplished (reference Airbus Service Bulletin A320- 71-1021, Revision 01, dated June 10, 1998); 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 (c) 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 specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously. To prevent structural failure of the forward engine mount secondary load path, which, if combined with failure of the primary load path, could result in separation of the engine from the airplane, accomplish the following: (a) Within 500 flight hours after the effective date of this AD: Perform a one-time visual inspection of the forward engine mount assembly of the left and right engines to verify that the part number (P/N) on each assembly is correct, in accordance with Airbus Service Bulletin A320-71-1021, Revision 01, dated June 10, 1998. (1) If the P/N on the forward engine mount assembly of the left and right engines is 740-2010-513N or 740-2010-513 with a revision of `N' or higher, prior to further flight, re-identify each assembly in accordance with the service bulletin. No further action is required by this AD. (2) If the P/N on the forward engine mount assembly of the left and right engines is different from the P/N's specified in paragraph (a)(1) of this AD, or if the P/N cannot be determined: Prior to further flight, perform a detailed visual inspection to detect any crack or failure of the thrust links on each forward engine mount assembly, in accordance with the service bulletin. (i) If no crack or failure of any thrust link on the left or right engine is detected: Within 2,250 landings following accomplishment of the inspection specified in paragraph (a)(2) of this AD, or at the next engine removal, whichever occurs first, modify each engine mount and its installation, and re-identify each forward engine mount assembly; in accordance with the service bulletin. (ii) If any crack or failure of any thrust link on the left or right engine is detected, prior to further flight, replace the existing thrust link with a new thrust link, modify each engine mount, and re-identify each forward engine mount assembly; in accordance with the service bulletin.

Note 2: Inspection and modification of the engine mount assembly accomplished prior to the effective date of this AD in accordance with Airbus Service Bulletin A320-71-1021, dated February 6, 1998, is considered acceptable for compliance with the applicable actions specified in this AD.

(b) As of the effective date of this AD, no person shall install a forward engine mount assembly on any airplane equipped with International Aero Engines (IAE) V2500-A5 engines, unless the actions described in Airbus Service Bulletin A320-71-1021, dated February 6, 1998, or Revision 01, dated June 10, 1998, have been accomplished for that assembly.

Note 3: Airbus Service Bulletin A320-71-1021, Revision 01, dated June 10, 1998, references V2500 IAE Service Bulletin V2500-NAC-71- 0135, Revision 1, dated March 5, 1998, as an additional source of service information for accomplishment of the actions specified in this AD.

(c) 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, FAA, Transport Airplane Directorate. 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 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

(d) 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.

Note 5: The subject of this AD is addressed in French airworthiness directive 98-293-118(B), dated July 29, 1998.

Issued in Renton, Washington, on November 16, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 98-31177 Filed 11-20-98; 8:45 am] BILLING CODE 4910-13-U