01-22090. Airworthiness Directives; Airbus Model A319, A320, and A321 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Airbus Model A319, A320, and A321 series airplanes, that currently requires a one-time ultrasonic inspection to detect disbonding of the skin attachments at the stringers and spars of the vertical stabilizer, and repair, if necessary. For certain airplanes, that AD also requires prior or concurrent modification of the vertical stabilizer to ensure proper reinforcement of its attachment to the skin. This action would require ultrasonic inspections of the subject area, and repair, as necessary. It would also require installation of fasteners to reinforce the bonds to the skin, which would terminate 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 necessary to prevent failure of the bonds of the vertical stabilizer spar boxes to the skin, which could lead to reduced structural integrity of the spar boxes.

DATES:

Comments must be received by October 4, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket Number 2000-NM-413-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. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2000-NM-413-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

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:

Dan Rodina, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

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 action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-413-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 Number 2000-NM-413-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On June 2, 2000, the FAA issued AD 2000-11-27, amendment 39-11776 (65 FR 37029, June 13, 2000), applicable to certain Airbus Model A319, A320, and A321 series airplanes, to require a one-time ultrasonic inspection to detect disbonding of the skin attachments at the stringers and spars of the vertical stabilizer, and repair, if necessary. For certain airplanes, that AD also requires prior or concurrent modification of the vertical stabilizer to ensure proper reinforcement of its attachment to the skin. That AD was prompted by reports received from the Direction Générale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, of localized failure of bonds of the spars and stringers on several vertical stabilizer spar boxes to the skin. The failure resulted from contamination of the bonding surface during the production process. The requirements of that AD are intended to detect and correct disbonding of the vertical stabilizer structure, which could result in reduced structural integrity of the spar boxes of the vertical stabilizer.

In the preamble of AD 2000-11-27, the FAA indicated that the actions required by that AD were considered to be interim action. Airbus had advised that it was then developing a program of repetitive inspections to address the localized disbonding. The FAA indicated that it might consider additional rulemaking once the repetitive inspection program had been developed, approved, and made available.

Since the issuance of AD 2000-11-27, Airbus has developed a program for repetitive ultrasonic inspections of the bonds between the spars and stringers of the vertical stabilizer spar boxes and the skin. Airbus has also developed a program for installation of fasteners to reinforce the bond of the vertical stabilizers to the skin, which terminates the repetitive ultrasonic inspections. Airbus has incorporated these programs into the service bulletins described below.

Explanation of Relevant Service Information

Airbus has issued Service Bulletin A320-55A1027, Revision 02, dated February 13, 2001, which describes procedures for repetitive ultrasonic inspections of the spars and stringers of the vertical stabilizer spar box for failure of the bonds to the skin; and procedures for repair of localized areas of disbonding.

Airbus has also issued Service Bulletin A320-55-1028, Revision 03, dated November 2, 2000, which describes procedures for installation of fasteners to reinforce those areas where the bond between the spars and stringers of the vertical stabilizer spar box and the skin are susceptible to failure. This installation terminates the repetitive inspections of the vertical stabilizer spar box.

Accomplishment of the actions specified in these service bulletins is intended to adequately address the identified unsafe condition. The DGAC classified both service bulletins as mandatory and issued French airworthiness directive 2000-520-159(B), dated December 13, 2000, 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 § 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 supersede AD 2000-11-27 to require repetitive ultrasonic inspection to detect disbonding of the skin attachments at the stringers and spars of the vertical stabilizer; and repair, if necessary. For certain airplanes, the proposed AD would continue to require prior or concurrent modification of the vertical stabilizer to ensure proper reinforcement of its attachment to the skin. The proposed AD would also require installation of fasteners to reinforce the bonds to the skin, which would constitute terminating action for the repetitive inspections. The actions would be required to be accomplished in accordance with the service bulletins described previously.

Cost Impact

There are approximately 23 airplanes of U.S. registry that would be affected by this proposed AD.

The repetitive inspections that are proposed in this AD would take approximately 3 to 7 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts would be provided by the airplane manufacturer at no cost to operators. Based on these figures, the cost impact on U.S. operators of the repetitive inspections proposed in this AD is estimated to be $4,140 to $9,660, or $180 to $420 per airplane, per inspection cycle.

The installation of fasteners proposed in this AD would take approximately 5 to 480 work hours per airplane to accomplish, depending upon the configuration of the airplane, at an average labor rate of $60 per work hour. Required parts would be provided by the airplane manufacturer at no cost to operators. Based on these figures, the cost impact on U.S. operators of the modification proposed in this AD is estimated to be $6,900 to $662,400, or $300 to $28,800 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of the proposed AD, 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 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

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.

§ 39.13

[Amended]

2. Section 39.13 is amended by removing amendment 39-11776 (65 FR 37029, June 13, 2000), and by adding a new airworthiness directive (AD), to read as follows:

Airbus Industrie: Docket 2000-NM-413-AD. Supersedes AD 2000-11-27, Amendment 39-11776.

Applicability: Model A319, A320, and A321 series airplanes; certificated in any category; as listed in Airbus Service Bulletin A320-55A1027, dated May 13, 2000; Revision 01, dated August 1, 2000; or Revision 02, dated February 13, 2001, except those airplanes which have incorporated Modification No. 30432K6788, in accordance with Airbus Service Bulletin A320-55-1028, Revision 03, dated November 2, 2000.

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 (g)(1) 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 failure of the bonds of the vertical stabilizer spar box to the skin, which could lead to reduced structural integrity of the spar box, accomplish the following:

Restatement of Requirements of AD 2000-11-27

Ultrasonic Inspection

(a) Within 60 days after June 28, 2000 (the effective date of AD 2000-11-27, amendment 39-11776): Perform a one-time ultrasonic inspection to detect disbonding (damage) of the skin attachments the stringers and spars of the vertical stabilizer, left- and right-hand sides, in accordance with Airbus Service Bulletin A320-55A1027, dated May 13, 2000; Revision 01, dated August 1, 2000; or Revision 02, dated February 13, 2001.

Modification (for Certain Airplanes)

(b) For airplanes with manufacturer's serial numbers listed in paragraph B of the Planning Information of Airbus Service Bulletin A320-55A1027, dated May 13, 2000; Revision 01, dated August 1, 2000; or Revision 02, dated February 13, 2001: Prior to or concurrent with the ultrasonic inspection required by paragraph (a) of this AD, modify the vertical stabilizer to ensure proper reinforcement of the structure/skin attachments, in accordance with Airbus Service Bulletin A320-55-1026, Revision 01, dated May 20, 1999.

New Requirements of Proposed AD

Repetitive Inspections and Repair, If Necessary

(c) Within 1,100 flight cycles from the previous inspection performed in accordance with paragraph (a) of this AD, or 60 days after the effective date of this AD, whichever occurs later: Perform an ultrasonic inspection to detect disbonding of the skin attachment at the spars and the stringers of the vertical stabilizer spar box, in accordance with Airbus Service Bulletin A320-55A1027, dated May 13, 2000; Revision 01, dated August 1, 2000; or Revision 02, dated February 13, 2001.

(d) If no damage is detected, or if only a single area of damage is found and it is less than or equal to an area of 300 square millimeters (mm²) during any ultrasonic inspection required by this AD, repeat the ultrasonic inspection thereafter at intervals not to exceed 1,100 flight cycles.

(e) If any damage is detected and the area of damage found is greater than 300 mm², or if multiple damage is found on one specific component (stringer/spar attachment) during any ultrasonic inspection required by this AD, prior to further flight, accomplish applicable repairs in accordance with Airbus Service Bulletin A320-55A1027, dated May 13, 2000; Revision 01, dated August 1, 2000; or 02, dated February 13, 2001. Repeat the ultrasonic inspection thereafter at intervals not to exceed 1,100 flight cycles.

Modification

(f) Within 5 years after the date of manufacture of the airplane: Install fasteners to reinforce the attachment between the skin panel and areas of the vertical stabilizer affected by disbonding, in accordance with Airbus Service Bulletin A320-55-1028, Revision 03, dated November 2, 2000. Accomplishment of the installation terminates the repetitive inspections required by paragraph (c) of this AD.

Alternative Methods of Compliance

(g)(1) 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.

(2) Alternative methods of compliance, approved previously in accordance with AD 2000-11-27, amendment 39-11776, are approved as alternative methods of compliance with paragraphs (a) and (b) of this AD.

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.

Special Flight Permits

(h) Special flight permits may be issued in accordance with §§ 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 directive 2000-520-159(B), dated December 13, 2000.

Issued in Renton, Washington, on August 27, 2001.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate Aircraft, Certification Service.