[Federal Register Volume 63, Number 71 (Tuesday, April 14, 1998)] [Proposed Rules] [Pages 18164-18167] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 98-9753] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 98-NM-08-AD] RIN 2120-AA64 Airworthiness Directives; Airbus Model A320 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 all Airbus Model A320 series airplanes. This proposal would require repetitive inspections to detect fatigue cracking in certain areas of the fuselage; and corrective action, if necessary. This proposal also would provide for an 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 fuselage, which could result in reduced structural integrity of the airplane. DATES: Comments must be received by May 14, 1998. [[Page 18165]] ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-08-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 98-NM-08-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-08-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 all Airbus Model A320 series airplanes. The DGAC advises that, during full-scale fatigue testing, cracking was detected at flight cycles varying from 76,000 to 111,664 in several areas of the fuselage:On the bottom panel of the keel beam at the frame 46, stringer 37 intersection at the pressure bulkhead; On the outboard flanges of frames 38 through 41, between stringers 12 and 21, originating at the fastener holes; and On the upper rivet row on the outer skin panel of the longitudinal lap joint, between frames 53 and 54, in the area of stringer 6; and between frames 48 and 64. Such fatigue cracking, if not detected and corrected in a timely manner, could result in reduced structural integrity of the airplane. Explanation of Relevant Service Information Airbus has issued Service Bulletin A320-53-1034, dated March 30, 1992, which describes procedures for repetitive ultrasonic inspections to detect cracking in the bottom panels of the keel beam (both left and right), in the area of the frame 46 and stringer 37 intersection at the pressure bulkhead; and repair, if necessary. Airbus also has issued Service Bulletin A320-53-1033, Revision 3, dated July 4, 1994, which describes procedures for modification of six specific fastener holes in the area of the frame 46 and stringer 37 intersection. This modification involves removing existing fasteners; cleaning the fastener holes; performing an eddy current inspection of the fastener holes to detect cracking, and repairing cracking if necessary; cold expanding the crack-free fastener holes; and installing oversize fasteners. Accomplishment of this modification would eliminate the need for the repetitive inspections specified in Airbus Service Bulletin A320-53-1034. Airbus also has issued Service Bulletin A320-53-1032, Revision 1, dated January 15, 1998, which describes procedures for repetitive visual inspections to detect cracking on the outboard flanges around the fastener holes of frames 38 to 41, between stringers 12 and 21; and repair, if necessary. Airbus also has issued Service Bulletin A320-53-1031, dated December 9, 1994, which describes procedures for modification of frames 38 to 41, between stringers 12 and 21. This modification involves cold expanding fastener holes and replacing the existing fasteners with new fasteners. Accomplishment of this modification, if performed prior to the accumulation of 20,000 total flight cycles, would eliminate the need for the repetitive inspections specified in Airbus Service Bulletin A320-53-1032. Airbus also has issued Service Bulletin A320-53-1057, Revision 2, dated July 5, 1996, which describes procedures for repetitive visual or eddy current inspections to detect cracking in the upper rivet row of the outer skin panel of the longitudinal lap joints in four specific areas; and repair, if necessary. The following areas are to be inspected: Between frames 48 and 64, next to stringer 6, on the left- and right-hand sides of the fuselage; Between frames 60 and 64, next to stringer 32, on the left-hand side of the fuselage; Between frames 59 and 64, next to stringer 32, on the right-hand side of the fuselage; and Between frames 58 and 64, next to stringer 41, on the right-hand side of the fuselage. Airbus also has issued Service Bulletin A320-53-1056, Revision 02, dated February 16, 1998, which describes procedures for modification of the outer skin panel of the longitudinal lap joints in multiple areas of the rear fuselage. This modification involves measuring the protrusion of existing rivets in the upper rivet rows of the longitudinal lap joints; and replacing existing rivets with repair rivets, if necessary. Accomplishment of this modification, if performed prior to the accumulation of 20,000 total flight cycles, would eliminate the need for the repetitive inspections specified in Airbus Service Bulletin A320-53-1057. Accomplishment of the modifications specified in Airbus Service Bulletins A320-53-1033, A320-53-1031, and A320-53-1056 is intended to adequately address the identified unsafe condition. The DGAC classified Airbus Service Bulletins A320-53-1034, A320-53- 1032, and A320-53-1057 as mandatory and issued French airworthiness directives 97-314-108(B), 97-313-107(B), and 97-312-106(B), all dated October 22, 1997, in order to assure the [[Page 18166]] continued airworthiness of these airplanes in France. FAA's Conclusions This airplane model is manufactured in France and is 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. 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 Airbus Service Bulletins A320-53-1034, A320- 53-1032, and A320-53-1057, described previously, except as discussed in the paragraphs that explain differences between this proposed rule and the service bulletins (below). In addition, this proposed AD 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 Bulletins Operators should note that, unlike the procedures described in Airbus Service Bulletins A320-53-1034, A320-53-1032, and A320-53-1057, this proposed AD would not permit further flight if cracking is detected in any section of the fuselage. The FAA has determined that, because of the safety implications and consequences associated with such cracking, any portion of the fuselage that is found to be cracked must be repaired or modified prior to further flight, in accordance with the applicable service bulletin, except as discussed in the next paragraph. Operators also should note that, although Airbus Service Bulletins A320-53-1034, A320-53-1033, and A320-53-1032 specify that the manufacturer may be contacted for disposition of certain repair conditions, this proposed AD would require the repair of those conditions to be accomplished in accordance with a method approved by the FAA. Cost Impact The FAA estimates that 118 airplanes of U.S. registry would be affected by this proposed AD. It would take approximately 6 work hours per airplane to accomplish the proposed ultrasonic inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the ultrasonic inspection proposed by this AD on U.S. operators is estimated to be $42,480, or $360 per airplane, per inspection cycle. It would take approximately 19 work hours per airplane to accomplish the proposed visual inspection on the outboard flanges, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the visual inspection proposed by this AD on U.S. operators is estimated to be $134,520, or $1,140 per airplane, per inspection cycle. It would take approximately 15 work hours per airplane to accomplish either the visual or eddy current inspection of the longitudinal lap joints, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these inspections proposed by this AD on U.S. operators is estimated to be $106,200, or $900 per airplane, per inspection cycle. The cost impact figures discussed above are 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. Should an operator elect to accomplish the optional terminating action specified in Airbus Service Bulletin A320-53-1033 that would be provided by this AD action, it would take approximately 5 work hours to accomplish it, at an average labor rate of $60 per work hour. The cost of required parts would be approximately $72 per airplane. Based on these figures, the cost impact of that optional terminating action would be $372 per airplane. Should an operator elect to accomplish the optional terminating action specified in Airbus Service Bulletin A320-53-1031 that would be provided by this AD action, it would take approximately 1 work hour (excluding access and closeup) per fastener hole to accomplish it, at an average labor rate of $60 per work hour. The cost of required parts would be approximately $4,047 (for one modification kit). Based on these figures, the cost impact of that optional terminating action would be a minimum of $4,107 per airplane. Should an operator elect to accomplish the optional terminating action specified in Airbus Service Bulletin A320-53-1056 that would be provided by this AD action, it would take approximately 258 work hours to accomplish it, at an average labor rate of $60 per work hour. The cost of required parts would be approximately $420 per airplane. Based on these figures, the cost impact of that optional terminating action would be $15,900 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: [[Page 18167]] 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-08-AD. Applicability: All Model A320 series airplanes, certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 (h) 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 fuselage, which could result in reduced structural integrity of the airplane, accomplish the following: (a) For airplanes on which Airbus Modification 21202 (reference Airbus Service Bulletin A320-53-1033, Revision 3, dated July 4, 1994) has not been accomplished: Prior to the accumulation of 30,000 total flight cycles, or within 6 months after the effective date of this AD, whichever occurs later, perform an ultrasonic inspection to detect cracking in the bottom panels of the keel beam (both left and right), in the area of the frame 46 and stringer 37 intersection at the pressure bulkhead, in accordance with Airbus Service Bulletin A320-53-1034, dated March 30, 1992. Thereafter, repeat the ultrasonic inspection at intervals not to exceed 6,000 flight cycles. If any crack is found, prior to further flight, repair in accordance with the service bulletin, except as provided by paragraph (g) of this AD. (b) Accomplishment of Airbus Modification 21202 in accordance with Airbus Service Bulletin A320-53-1033, Revision 3, dated July 4, 1994, constitutes terminating action for the repetitive inspection requirement of paragraph (a) of this AD. (c) For airplanes on which Airbus Modification 21346 (reference Airbus Service Bulletin A320-53-1031, dated December 9, 1994) has not been accomplished prior to the accumulation of 20,000 total flight cycles: Prior to the accumulation of 30,000 total flight cycles, or within 6 months after the effective date of this AD, whichever occurs later, perform a visual inspection to detect cracking on the outboard flanges around the fastener holes of frames 38 to 41, between stringers 12 and 21, in accordance with Airbus Service Bulletin A320-53-1032, Revision 1, dated January 15, 1998. Thereafter, repeat the visual inspection at intervals not to exceed 6,000 flight cycles. If any crack is found, prior to further flight, repair in accordance with the service bulletin, except as provided by paragraph (g) of this AD. Accomplishment of a repair in accordance with the service bulletin terminates the repetitive inspection requirements for the area repaired. (d) Accomplishment of Airbus Modification 21346 in accordance with Airbus Service Bulletin A320-53-1031, dated December 9, 1994, prior to the accumulation of 20,000 total flight cycles constitutes terminating action for the repetitive inspection requirement of paragraph (c) of this AD. (e) For airplanes on which Airbus Modification 21905 (reference Airbus Service Bulletin A320-53-1056, Revision 02, dated February 16, 1998) has not been accomplished: Prior to the accumulation of 20,000 total flight cycles, or within 6 months after the effective date of this AD, whichever occurs later, perform a visual or eddy current inspection to detect cracking in the upper rivet row of the longitudinal lap joint, in accordance with Airbus Service Bulletin A320-53-1057, Revision 2, dated July 5, 1996. (1) Thereafter, repeat the inspection at one of the following intervals: (i) If the immediately preceding inspection was conducted using visual techniques, conduct the next inspection within 4,000 flight cycles. (ii) If the immediately preceding inspection was conducted using eddy current techniques, conduct the next inspection within 12,000 flight cycles. (2) If any crack is found, prior to further flight, repair in accordance with the service bulletin, except as provided by paragraph (g) of this AD. Accomplishment of a repair in accordance with the service bulletin terminates the repetitive inspection requirements for the area repaired. (f) Accomplishment of Airbus Modification 21905 in accordance with Airbus Service Bulletin A320-53-1056, Revision 02, dated February 16, 1998, prior to the accumulation of 20,000 total flight cycles constitutes terminating action for the repetitive inspection requirements specified in paragraph (e)(1) of this AD. (g) If any crack is found during any inspection required by paragraph (a), (c), or (e) of this AD, and the applicable service bulletin specifies to contact Airbus for appropriate action: Prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate. (h) 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. (i) 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 3: The subject of this AD is addressed in French airworthiness directives 97-314-108(B), 97-313-107(B), and 97-312- 106(B), all dated October 22, 1997. Issued in Renton, Washington, on April 7, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 98-9753 Filed 4-13-98; 8:45 am] BILLING CODE 4910-13-P