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 Airbus Model A319, A320, and A321 series airplanes was published in the Federal Register on October 15, 2003 (68 FR 59347). That action proposed to require repetitive inspections of the left- and right-side main landing gear (MLG) side-stay cuff lugs and down-lock spring attachments for evidence of cracked or fractured side-stay cuff lugs or down-lock spring attachments, and repair if necessary. That action also provided for optional terminating action for the repetitive inspections.
Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.
Support of the Proposed AD
Several commenters, including the airplane manufacturer, support the intent of the proposed AD.
Request To Reference Revised Service Information
Several commenters note that Airbus has revised the service information cited in the proposed AD. The commenters suggest that the proposed AD be changed to reference the revised service information, as identified in the following table.
Table--Revised Service Information/Service Information Cited in Proposed AD
Revised Airbus service information
Cited in the proposed AD as
For accomplishing the
Referenced in the following paragraph(s) of the proposed AD
Airbus A319/A320/A321 Maintenance Planning Document, Revision 26a,
dated July 31, 2003.
Airbus A318/A319/A320/A321 Maintenance Planning Document, Revision 25, dated October 2001.
Alternative to the inspection requirements in paragraph (a) of the proposed AD.
(d).
A320 32 1223, Revision 01, dated June 11, 2002.
A320 32 1223, dated March 5, 2001
Optional terminating action
(e).
A320 32A1224, Revision 01, dated June 11, 2002.
A320 32A1224, dated
January 18,2001.
Inspection and part replacement
(a) and (c).
We agree that this AD should reference the revised Airbus service information. We have reviewed the revised service information and determined that the majority of changes are editorial. Revision 01 of Service Bulletin A320-32A1224 includes the compliance times mandated in French airworthiness directive 2002-075(B), dated January 23, 2002. Instead of referring operators to Chapter 32-11-19 of the Airbus A319/ A320/A321 Aircraft Maintenance Manual, Revision 01 includes Figure 1, which shows the inspection areas for the side-stay cuffs and links. We have revised paragraphs (a) and (c) of this AD to reference Airbus Service Bulletin A320-32A1224, Revision 01, dated June 11, 2002, and removed the citation for the original issue of that service bulletin. We have also included a new paragraph (d) in this AD to give credit for inspections and part replacements accomplished before the effective date of this AD, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-32A1224, dated January 18, 2001, and changed the designations of the subsequent paragraphs.
We have revised paragraph (e) of this AD (paragraph (d) of the proposed AD) to include Revision 26a, dated July 31, 2003, of the Airbus A318/A319/A320/A321 Maintenance Planning Document (MPD). In addition, we have revised the description of task number 321119-01-1 to reflect the description as changed in Revision 26a of the MPD.
In addition, we have revised paragraph (f) of this AD (paragraph (e) of the proposed AD) to include the citation for Service Bulletin A320-32-1223, Revision 01, dated June 11, 2002, as an additional source of service information for accomplishing the optional terminating action.
Request To Change Type of Inspection
Two commenters note that paragraph (a) of the proposed AD specifies that operators should do a detailed inspection for cracked or fractured lugs. The commenters point out that theparallel French airworthiness directive, 2002-075(B), dated January 23, 2002; Airbus Service Bulletin A320-32A1224, Revision 01; and task number 321119-01-1, "Mechanism Visual Check of Main Landing Gear Downlocking Springs and Side-stay Center Joint Links and Cuff," of the Airbus A318/A319/A320/A321 MPD; recommend a visual check to ensure the lugs are not ruptured. The commenters suggest that the inspection terminology in the proposed AD be changed from "detailed inspection" to "visual check" in order to harmonize with the Airbus service information. One commenter states that the intent of the action is to look for obvious damage; therefore, visual check is more appropriate verbiage than detailed inspection.
We agree with the intent of the commenters' requests and have revised paragraph (a) of this AD to reference a "general visual inspection" instead of a "detailed inspection." We also revised Note 1 of this AD to provide the definition of a general visual inspection. When included in an AD, the term "check" means something other than a cursory inspection of an item, and the requirements of this AD do not warrant the use of that term.
Request To Revise Compliance Time
One commenter requests that the compliance times in paragraph (a) of the proposed AD be changed from flight hours to flight cycles. Specifically, the commenter requests that paragraph (a)(1) of the proposed AD be changed from "Within 60 months from the first entry into service of the MLG, or before the accumulation of 9,000 total flight hours on the MLG, whichever occurs first" to "Within 60 months from the first entry into service of the MLG, or before 7,200 total flight cycles on the MLG, whichever occurs first." The commenter also requests that the compliance time in paragraph (a)(2) of the proposed AD be changed from "Within 500 flight hours on the MLG after the effective date of this AD" to "Within 500 flight cycles on the MLG after the effective date of this AD." The commenter states that it tracks MLG side-stays by flight cycles, in accordance with its approved maintenance program, and that changing the initial inspection to flight cycles would allow the inspection to be incorporated within a scheduled maintenance check. The commenter did not provide any information regarding how it converted 9,000 total flight hours to 7,200 total flight cycles, or how it converted 500 flight hours to 500 flight cycles.
We agree with the intent of the commenter's request, but we do not agree to revise the compliance times in paragraphs (a)(1) and (a)(2) of this AD from flight hours to flight cycles. We do not have any technical justification for making the requested changes. When determining the compliance time for this AD, we considered the compliance time specified in the parallel French airworthiness directive, the airplane manufacturer's recommendation, and the average utilization of the affected fleet. According to the provisions of paragraph (g) of this AD, anyonemay submit a request to adjust the compliance time if the request includes data that justify that a different compliance time would provide an acceptable level of safety. We have not changed this AD regarding this issue.
Explanation of Change to This AD
Paragraphs (b), (c), and (e) of this AD have been revised to change the repetitive inspection intervals from 500 flight cycles to 500 flight hours. Although the French airworthiness directive, the Airbus service information, and the compliance times in paragraph (a) of this AD state compliance times in flight hours, we inadvertently stated the repetitive inspection intervals in flight cycles instead of flight hours.
Conclusion
We have carefully reviewed the available data, including the comments that have been submitted, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden onany operator nor increase the scope of the AD.
Cost Impact
We estimate that 367 airplanes of U.S. registry will be affected by this AD, that it will take approximately 2 work hours per airplane to accomplish the required actions, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $130 per airplane, per inspection cycle.
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. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements." Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.
Regulatory Impact
The regulations adopted herein will not have a substantial direct effect on the States, on the relationshipbetween 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 final rule does not have federalism implications under Executive Order 13132.
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.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: