[Federal Register Volume 64, Number 175 (Friday, September 10, 1999)] [Proposed Rules] [Pages 49110-49112] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-23477] [[Page 49110]] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 99-NM-184-AD] RIN 2120-AA64 Airworthiness Directives; Airbus Model A330 and A340 Series Airplanes AGENCY: Federal Aviation Administration, DOT. ACTION: Notice of proposed rulemaking (NPRM). ----------------------------------------------------------------------- SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Airbus Model A330 and A340 series airplanes. This proposal would require repetitive detailed visual inspections to detect cracking of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing; and corrective actions, if necessary. This proposed AD also provides for optional terminating action for the repetitive inspections. 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 detect and correct fatigue cracking of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing, which could result in reduced structural integrity of the belly fairing. DATES: Comments must be received by October 12, 1999. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-184-AD, 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 99-NM-184-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. 99-NM-184-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 A330 and A340 series airplanes. The DGAC advises that during full-scale fatigue testing, fatigue cracking occurred in one of the inboard Z-stiffeners at the fitting retaining the centerline panel between the main landing gear doors. The cracking initiated in the cut-out radius of the vertical flange and propagated downward. Such fatigue cracking, if not detected and corrected, could result in reduced structural integrity of the belly fairing. Explanation of Relevant Service Information The manufacturer has issued Airbus Service Bulletins A330-53-3020 (for Model A330 series airplanes) and A340-53-4029 (for Model A340 series airplanes); each dated November 30, 1995. These service bulletins describe procedures for repetitive detailed visual inspections to detect cracking of the vertical flange of the inboard Z- stiffeners of the centerline panel of the fuselage belly fairing; and corrective actions, if necessary. The detailed visual inspection includes the left- and right-hand sides of the centerline panel between the main landing gear doors. The corrective actions reference the accomplishment of Airbus Service Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-4028 (for Model A340 series airplanes); each dated November 30, 1995. These service bulletins describe procedures for modification of the vertical flange of the inboard Z- stiffeners of the centerline panel of the fuselage belly fairing. The modification involves the installation of a new cut-out of the vertical flange of the inboard Z-stiffeners; and installation of an external reinforcement plate (strap), and modification of the assembly (length of fasteners) between the Z-stiffeners and the belly fairing panel. Accomplishment of the modification of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing eliminates the need for the repetitive inspections, provided that all cracking is eliminated. Accomplishment of the actions specified in the applicable service bulletins is intended to adequately address the identified unsafe condition. The DGAC classified Airbus Service Bulletins A330-53-3020 and A340-53-4029 as mandatory and issued French airworthiness directives 96-056-029 (B) (for Model A330 series airplanes), and 96-057-042 (B) (for Model A340 series airplanes); each dated March 13, 1996; 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 [[Page 49111]] 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. 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, this proposed AD would require accomplishment of the actions specified in the service bulletins described previously, except as discussed below. This proposed AD also would provide for optional terminating action for the repetitive inspections. Operators should note that, in consonance with the findings of the DGAC, the FAA has determined that the repetitive inspections proposed by this AD can be allowed to continue in lieu of accomplishment of a terminating action. In making this determination, the FAA considers that, in this case, long-term continued operational safety will be adequately assured by accomplishing the repetitive inspections to detect cracking before it represents a hazard to the airplane. Differences Between Proposed Rule and Service Bulletin Unlike the procedures described in Airbus Service Bulletins A330- 53-3020 (for Model A330 series airplanes) and A340-53-4029 (for Model A340 series airplanes), this proposed AD would not permit further flight if cracks are detected of the vertical flange of the inboard Z- stiffeners of the centerline panel of the fuselage belly fairing. The FAA has determined that, because of the safety implications and consequences associated with such cracking, any vertical flange of the inboard Z-stiffener that is found to be cracked must be repaired or modified to eliminate any cracking, or repaired (for any cracking that cannot be eliminated), prior to further flight. Operators also should note that, although the service bulletins specify that the manufacturer may be contacted for disposition of certain cracking conditions, this proposal would require the repair of those conditions to be accomplished in accordance with a method approved by the FAA. Cost Impact None of the airplanes affected by this action are on the U.S. Register. All airplanes included in the applicability of this proposed rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this proposed AD action. However, the FAA considers that this proposed rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject airplanes are imported and placed on the U.S. Register in the future. Should an affected airplane be imported and placed on the U.S. Register in the future, it would require approximately 1 work hour to accomplish the proposed inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this AD would be $60 per airplane, per inspection cycle. Should an operator elect to accomplish the optional terminating action proposed by this AD, it would require approximately 7 work hours to accomplish the proposed optional terminating action, at an average labor rate of $60 per work hour. Required parts would cost approximately $2,350 per airplane. Based on these figures, the cost impact of the optional terminating action is estimated to $2,770 per airplane. 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 99-NM-184-AD. Applicability: Model A330 and A340 series airplanes; except those airplanes on which Airbus Modification 42605, or Airbus Service Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-4028 (for Model A340 series airplanes) has been accomplished; 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 detect and correct fatigue cracking of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing, which could result in reduced structural integrity of the belly fairing, accomplish the following: Repetitive Detailed Visual Inspections (a) Prior to the accumulation of 5,500 total flight cycles, or within 500 flight hours after the effective date of this AD, whichever occurs later, perform a detailed visual inspection to detect cracking of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing, in accordance with Airbus Service Bulletin A330-53-3020 (for Model A330 series airplanes) or A340-53-4029 (for Model A340 series airplanes); each dated November 30, 1995; as applicable. Note 2: For the purposes of this AD, a detailed visual inspection is defined as: ``An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc. may be used. Surface cleaning and elaborate access procedures may be required.'' [[Page 49112]] (1) If no cracking is detected, repeat the inspection thereafter at intervals not to exceed 5,500 flight cycles, until the requirements of paragraph (b) of this AD are accomplished. Corrective Actions (2) If any cracking is detected during any inspection required by this AD, prior to further flight, modify the vertical flange of both inboard Z-stiffeners of the centerline panel of the fuselage belly fairing and re-inspect the modified area to determine if cracking has been eliminated, in accordance with Airbus Service Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53- 4028 (for Model A340 series airplanes); each dated November 30, 1995; as applicable. (i) If all cracking is not eliminated after accomplishment of the modification, prior to further flight, repair in accordance with a method approved by either the Manager, International Branch, ANM- 116, FAA, Transport Airplane Directorate; or the Direction Generale de l'Aviation Civile (DGAC) (or its delegated agent). For a repair method to be approved by the Manager, International Branch, ANM-116, as required by this paragraph, the Manager's approval letter must specifically reference this AD. (ii) If all cracking is eliminated after the accomplishment of the modification, no further action is required by this AD. Optional Terminating Action (b) Modification of the vertical flange of both inboard Z- stiffeners of the centerline panel of the fuselage belly fairing in accordance with Airbus Service Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-4028 (for Model A340 series airplanes); each dated November 30, 1995; as applicable constitutes terminating action for the requirements of this AD. Alternative Methods of Compliance (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. 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 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116. Special Flight Permits (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 4: The subject of this AD is addressed French airworthiness directives 96-056-029 (B) and 96-057-042 (B); each dated March 13, 1996; in order to assure the continued airworthiness of these airplanes in France. Issued in Renton, Washington, on September 2, 1999. Dorenda D. Baker, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-23477 Filed 9-9-99; 8:45 am] BILLING CODE 4910-13-U