Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2016-07-12, Amendment 39-18457 (81 FR 19482, April 5, 2016) (``AD 2016-07-12''). AD 2016-07-12 applied to certain Airbus SAS Model A318, A319, A320, and A321 series airplanes. The NPRM published in the Federal Register on February 22, 2019 (84 FR 5617). The NPRM was prompted by reports of cracking of the AFF of the pylons due to fatigue damage of the structure and reports of cracks on a certain rib of a modified AFF of the pylons. The NPRM proposed to continue to require repetitive inspections for damage and cracking of the AFF of the pylons. The NPRM also proposed to require additional repetitive inspections at the upper spar at a certain rib area and corrective actions if necessary. The FAA is issuing this AD to address damage and cracking of the AFF of the pylons, which could result in detachment of a pylon and consequent reduced structural integrity of the airplane.
The EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2018-0137R1, dated January 9, 2019 (``EASA AD 2018-0137R1'') (also referred to as the Mandatory Continuing Airworthiness Information, or ``the MCAI''), to correct an unsafe condition for certain Airbus SAS Model A318-111, and -112; Model A319- 111, -112, -113, -114, and -115; Model A320-211, -212, -214, and -216; and Model A321-111, -112, -211, -212, and -213 airplanes. The MCAI states:
On aeroplanes equipped with post-mod 33844 CFM pylons, several operators reported finding cracks on the Aft Fixed Fairing (AFF). After material analysis, it appeared that the pylon AFF structure, especially on this configuration, was subject to fatigue-induced damage which could lead to pylon AFF cracks.
This condition, if not detected and corrected, could lead to detachment of a pylon AFF from the aeroplane, possibly resulting in injury to persons on the ground.To address this unsafe condition, Airbus published Alert Operators Transmission (AOT) A54N002-12, providing inspection instructions. Thereafter, Airbus issued Service Bulletin (SB) A320- 54-1027, later revised, superseding AOT A54N002-12. EASA issued AD 2014-0154 [which corresponds to FAA AD 2016-07-12] to require repetitive inspections of the pylon AFF and, depending on findings, replacement.
After that [EASA] AD was issued, Airbus developed mod 156593 to increase the fatigue life of the pylon AFF structure by using a different material and introducing thermal treatment of the aluminium sheets parts. Prompted by new findings of cracks on rib 15, it was determined that this area also needs to be inspected to ensure the structural integrity of the new pylon AFF. Airbus revised SB A320-54-1027, including instructions for repetitive inspection of that area. Repetitive inspections are also required on post-mod 156593 aeroplanes.
Airbus also developed mod 159806 and 156765, redesigning the corner fittings at the junction upper spar and rib 15, which constitutes terminating action for the repetitive inspections. For retrofit purposes, Airbus issued SB A320-54-1035 and SB A320-54- 1036, later revised, providing instructions to modify and re- identify the pylon AFF, which constitutes terminating action for the repetitive inspections.
For the reasons described above, EASA issued AD 2018-0137 [which was referred to as the appropriate source of service information for accomplishing the actions specified in the FAA NPRM], retaining the requirements of EASA AD 2014-0154, which was superseded, and requiring repetitive inspections of the upper spar at rib 15 area and, depending on findings, accomplishment of applicable corrective action(s). This [EASA] AD also included references to optional terminating actions, and provided installation requirements for the new pylon AFF.
Since that [EASA] AD was issued, comments and requests for clarification have been received from operators. This [EASA] AD is revised, merging the restatement of requirements of AD 2014-0154 with the new requirements.
You may examine the MCAI in the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2019- 0018.
Comments
The FAA gave the public the opportunity to participate in developing this final rule. The following presents the comments received on the NPRM and the FAA's response to each comment.
Support for the NPRM
Commenters Delta Air Lines (DAL), Jeff Hymen, and Megan Neeley indicated their support for the NPRM.
Request To Reference the Latest EASA AD
Alaska Airlines (Alaska) and DAL requested that the FAA refer to EASA AD 2018-0137R1 in lieu of EASA AD 2018-0137, dated July 12, 2018 (``EASA AD 2018-0137''). Alaska requested revision of paragraphs (c) and (g) of the proposed AD to cite EASA AD 2018-0137R1.
The FAA agrees with the commenters' requests. No additional work is required for airplanes on which the requirements of EASA AD 2018-0137, dated June 28, 2018 (``EASA AD 2018-0137''), have been accomplished. The FAA has revised paragraphs (c) and (g) of this AD to cite EASA AD 2018-0137R1 in addition to EASA AD 2018-0137. The FAA has also revised paragraph (h)(1)(i) of this AD to require the use of the effective date of this AD rather than the effective date of EASA 2018-0137 (July 12, 2018), as referenced in EASA ADs 2018-0137 and 2018-0137R1, to determine compliance.
Request To Remove Paragraph (h)(4) of the Proposed AD
DAL requested that paragraph (h)(4) of the proposed AD be removed, which did not allow for the provisions of paragraph (5) of EASA AD 2018-0137 (credit for actions done using certain service information). DAL argued that if the provisions of paragraph (5) of EASA AD 2018- 0137R1 are disallowed, the result would be a requirement that is more restrictive to U.S. operators. DAL further noted that disallowing paragraph (5) of EASA AD2018-0137R1, which allows credit for initial inspections
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using additional revisions of certain service information, would mean the initial inspections would have to be accomplished faster and may require special scheduled inspections, which often results in utilizing less experienced mechanics. DAL requested that the AD specify which revision of the EASA AD will be allowed. Accordingly, DAL requests that, if this AD is updated to reflect EASA AD 2018-0137R1, that paragraph (h)(4) of this AD be removed.
The FAA agrees with the request for the reasons provided. Also note that paragraph (5) of EASA AD 2018-0137R1 adds credit for initial inspections performed in accordance with Airbus Service Bulletin A320- 54-1027, dated April 10, 2014; and Airbus Service Bulletin A320-54- 1027, Revision 1, dated January 14, 2015; which were not included in paragraph (5) of EASA AD 2018-0137. Paragraph (h)(4) of the proposed AD is removed and paragraphs (h)(5) and (h)(6) of theproposed AD are redesignated as paragraphs (h)(4) and (h)(5) of this AD to reflect this request.
Request To Allow Re-Installation of an Affected Part Under Certain Circumstances
DAL requested that the AD allow for the re-installation of an affected AFF if it was removed for reasons other than meeting the requirement of the AD, such as routine maintenance. DAL pointed out that an affected AFF may need to be removed for access to perform either unrelated maintenance or for compliance with certain service information referenced in EASA ADs 2018-0137 and 2018-0137R1. DAL's interpretation of the ``do not install'' language in paragraph (11) of EASA AD 2018-0137 led it to believe that operators would struggle to comply with the instructions as written, and recommended that the FAA adds a statement that would allow the re-installation of an AFF that was removed from the airplane for the purpose of maintenance or inspections.
The FAA agrees to clarify. Group 1 airplanes, as specified in EASA ADs 2018-0137 and 2018-0137R1, are those that, as of the effective date of this AD, have an affected AFF installed. The intent of paragraph (11.1) of EASA ADs 2018-0137 and 2018-0137R1 is to prevent an affected AFF from being re-installed on a Group 1 airplane only if the modification specified in paragraph (9) or (10) of EASA AD 2018-0137 or EASA AD 2018-0137R1 has already been accomplished on that airplane. An operator has the full compliance time to accomplish the modification, and, up until the modification is accomplished, an affected AFF may be re-installed for reasons such as routine maintenance.
Group 2 airplanes, as specified in EASA ADs 2018-0137 and 2018- 0137R1, are those airplanes that, as of the effective date of this AD, do not have an affected AFF installed. For Group 2 airplanes, the intent of paragraph (11.2) of EASA ADs 2018-0137 and 2018-0137R1 is to prevent an affected AFF from being installed on an airplane on which an affected AFF was not alreadyinstalled as of the effective date of this AD. The AD has not been changed in this regard.
Request To Use Later Approved Revisions of Service Information
DAL pointed out that the reference publications section of EASA ADs 2018-0137 and 2018-0137R1 allows the use of later-approved revisions to the specified service information for compliance. DAL requested clarification to determine if this statement is applicable to this AD.
The AD does not exclude the ``Ref. Publications'' section of EASA ADs 2018-0137 and 2018-0137R1, so that section is applicable to this AD. The AD has not been changed in this regard.
Request To Add Exceptions for Alternative Methods of Compliance
DAL requested that the proposed AD be revised to add an exception that allows the use of consumable material list (CML) 10ABE1, ``touch up alodine,'' in addition to CML 10ABC1, ``tank alodine.'' DAL noted that while Airbus commonly specifies tank alodine, DAL prefers to use touch up alodine. DAL explained that they contacted Airbus on this issue and Airbus confirmed that touch up alodine can be used instead of tank alodine for the embodiment of Airbus Service Bulletin A320-54- 1027; Airbus Service Bulletin A320-54-1035; and Airbus Service Bulletin A320-54-1036.
DAL claimed that Airbus Service Bulletin A320-54-1027 and Airbus Service Bulletin A320-54-1035 state that all steps in the Procedure and Test sections are required for compliance (RC). DAL also maintained that some of those steps are corrosion prevention control program (CPCP) controlled tasks. Because corrosion inhibition compound (CIC) is part of CPCP, DAL argued that application of CIC should be managed by each individual operator regardless of the AD requirement. As a result, DAL requested language added to the proposed AD that allows for operators to control the reapplication of CICs as an alternative to the service information specifications.
DAL also noted that the ``Preparation'' section of the service information referenced in EASA ADs 2018-0137 and 2018-0137R1 contains references to a certain aircraft maintenance manual (AMM) section for basic aircraft configuration. The basic aircraft configuration of the AMM states that the aircraft is in the ``weight on wheels'' configuration. DAL noted that sometimes their airplanes are on jacks and that having the airplane in a weight on wheels configuration may limit the ability of their maintenance technicians to perform the required actions. DAL requested an exception to the proposed AD that allows for the required actions to be performed with either weight on wheels or while the aircraft is in a jacked configuration.
The FAA agrees with the request to add an exception that allows the use of CML 10ABE1, touch up alodine for the reasons provided. This AD has been revised to change the content of paragraph (h)(6) of this AD to state that where any service information referenced in EASA ADs 2018-0137 and 2018-0137R1 specifies to use CML materialnumber 10ABC1, this AD allows the use of CML material number 10ABE1 as an additional method of compliance.
The FAA disagrees with the request to add language to the proposed AD that allows for operators to control the reapplication of CICs via CPCP because not all U.S. operators have a standardized CPCP. If DAL cannot follow the CIC specified by Airbus in the service information, then they can reference the Airbus CML for an alternative CIC. Airbus's CML document contains a list of the latest consumables and alternatives that can be used. Operators may apply for an alternative method of compliance (AMOC) using the procedures in paragraph (j)(1) of this AD for using alternate consumables allowed in the CML with appropriate substantiations. The AD has not been changed in this regard.
The FAA agrees to clarify regarding the request for airplanes in a jacked configuration. The step the commenter referred to says to ``refer to'' the AMM. As noted in the service information, when thewords ``refer to'' are used and the operator has a FAA accepted alternative procedure, the accepted alternative procedure can be used. Operators therefore have latitude in how to accomplish any work steps that use the term ``refer to.'' This AD has not been changed in this regard.
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Request for Clarification of Repetitive Inspection Intervals
DAL requested clarification regarding the interval of the repetitive inspection specified in paragraph (3) of EASA ADs 2018-0137 and 2018-0137R1. DAL noted that, based on its understanding, the first repetitive inspection interval threshold is not to exceed 10,000 flight cycles or 15,000 flight hours, whichever occurs first. DAL remarked that it appears this threshold is based on the assumption that the initial inspections were done close to the initial threshold of 5,000 flight cycles or 7,500 flight hours, whichever occurred first. DAL requested clarification for a scenario in which an operator performed the specifiedinspection at 1,000 flight cycles or 1,000 flight hours, and asked if the first repetitive inspection interval would still be required before exceeding 10,000 flight cycles or 15,000 flight hours, whichever occurs first. DAL inquired if, in that same scenario, a grace period from the previous inspection would be more appropriate.
The FAA agrees to clarify. For the DAL scenario, the repetitive inspection will be due before exceeding 5,000 flight cycles or 7,500 flight hours, whichever occurs first since the last inspection. As stated previously, this AD now refers to EASA AD 2018-0137R1, as well as EASA AD 2018-0137. Paragraph (3) of EASA AD 2018-0137R1 has been revised to include multiple compliance times, including a grace period for airplanes on which an inspection has already been accomplished using earlier revisions of the service information or accomplishment of a certain maintenance planning document (MPD) task or a certain AOT. The AD has not been changed in this regard.Request To Clarify Revision Level for Optional Terminating Modification
DAL noted that paragraph (9) of EASA ADs 2018-0137 and 2018-0137R1 reference service information without a revision level. DAL inquired if the intent of the reference is to use only the original issue of the service information, or if any revision level is acceptable for compliance.
The FAA agrees to clarify. Operators may use any approved revision of the service information to perform the optional terminating modification, so long as the modification meets the provisions of paragraph (9) of EASA ADs 2018-0137 and 2018-0137R1.
Conclusion
The FAA reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule with the changes described previously and minor editorial changes. The FAA determined that these minor changes:
Are consistent with the intent that was proposed in the NPRM for addressing the unsafe condition; and
Do not add any additional burden upon the public than was already proposed in the NPRM.
The FAA also determined that these changes will not increase the economic burden on any operator or increase the scope of this final rule.
Related IBR Material Under 1 CFR Part 51
EASA AD 2018-0137 and EASA AD 2018-0137R1 describe procedures for repetitive inspections for pre- and post-Airbus SAS modification 156593 airplanes, corrective actions, and optional terminating actions for the repetitive inspections. Corrective actions include modifications and repair. These documents are distinct since EASA AD 2018-0137R1 omits certain language, provides credit for additional service information, and clarifies certain compliance times. This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.
Costs of Compliance
The FAA estimates that this AD affects 205 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:
Estimated Costs for Required Actions ----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators ---------------------------------------------------------------------------------------------------------------- Retained actions from AD 2016-07- 4 work-hours x $85 $0 $340............... $69,700.
12. per hour = $340. New proposed actions............. Up to 21 work-hours 0 Up to $1,785....... Up to $365,925.
x $85 per hour =
Up to $1,785. ----------------------------------------------------------------------------------------------------------------
Estimated Costs for Optional Actions ------------------------------------------------------------------------
Labor cost Parts cost Cost per product ------------------------------------------------------------------------ Up to 70 work-hours x $85 per Up to $32,800.... Up to $38,750.
hour = Up to $5,950. ------------------------------------------------------------------------
The FAA has received no definitive data that would enable the agency to provide cost estimates for the on-condition actions specified in this AD.
According to the manufacturer, some or all of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected individuals. The FAA does not control warranty coverage for affected individuals. As a result, the FAA has included all known costs in our cost estimate.
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.
The FAA is 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.
This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service,
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as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes and associated appliances to the Director of the System Oversight Division.
Regulatory Findings
The FAA determined that this AD will not have federalism implications under Executive Order 13132. This AD will 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.
For the reasons discussed above, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order 12866;
3. Will not affect intrastate aviation in Alaska; and
4. 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.