AD 2017-24-09

We are superseding Airworthiness Directive (AD) 2016-20-11, which applied to certain Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model A300 C4-605R Variant F airplanes (collectively called Model A300-600 series airplanes); and Airbus Model A310 series airplanes. AD 2016-20-11 required repetitive inspections of the external area of the aft cargo door sill beam for cracking, repetitive inspections for fatigue cracking of the cargo door sill beam, lock fitting, and torsion box plate, and repair if necessary. This new AD retains the inspections for cracking, and repair if necessary; and requires reinforcement of the aft cargo door sill beam area. This AD was prompted by the development of a reinforcement modification of the aft cargo door sill beam area, which constitutes terminating action for the repetitive inspections. We are issuing this AD to address the unsafe condition on these products.

Final rule.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0 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]

0 2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 2016-20-11, Amendment 39-18677 (81 FR 85837, November 29, 2016), and adding the following new AD:

2017-24-09 Airbus: Amendment 39-19113; Docket No. FAA-2017-0708; Product Identifier 2017-NM-035-AD.

(a) Effective Date

This AD is effective January 5, 2018.

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(b) Affected ADs

This AD replaces AD 2016-20-11, Amendment 39-18677 (81 FR 85837, November 29, 2016) (``AD 2016-20-11'').

(c) Applicability

This AD applies to the airplanes identified in paragraphs (c)(1) through (c)(5) of this AD, certificated in any category, all manufacturer serial numbers on which Airbus modification 05438 has been embodied in production, except those on which Airbus modification 12046 has been embodied in production.
(1) Airbus Model A300 B4-601, B4-603, B4-620, and B4-622 airplanes.
(2) Airbus Model A300 B4-605R and B4-622R airplanes.
(3) Airbus Model A300 F4-605R and F4-622R airplanes.
(4) Airbus Model A300 C4-605R Variant F airplanes.
(5) Airbus Model A310-203, -204, -221, -222, -304, -322, -324, and -325 airplanes.

(d) Subject

Air Transport Association (ATA) of America Code 53, Fuselage.

(e) Reason

This AD was prompted by reports of fatigue cracks on the cargo door sill beam, lock fitting, and torsion box plate. We are issuing this AD to prevent fatigue cracking of the cargo door sill beam, lock fitting, and torsion box plate, which could result in the loss of the door locking function and subsequently, loss of the cargo door in flight and rapid decompression.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Retained Inspection, With No Changes

This paragraph restates the requirements of paragraph (g) of AD 2016-20-11, with no changes. Within the compliance time identified in paragraph (g)(1), (g)(2), or (g)(3) of this AD, as applicable: Do an ultrasonic inspection or detailed inspection of the aft cargo door sill beam external area for cracking, in accordance with Airbus Alert Operators Transmission (AOT) A53W005-14, dated April 22, 2014; or Airbus AOT A53W005-14, Revision 01, dated April 29, 2014. Repeat the inspection thereafter at intervals not to exceed 275 flight cycles. As of January 3, 2017 (the effective date of AD 2016-20-11), use only Airbus AOT A53W005-14, Revision 01, dated April 29, 2014, to comply with the requirements of this paragraph.
(1) For airplanes that have accumulated 30,000 flight cycles or more since the airplane's first flight as of July 2, 2014 (the effective date of AD 2014-12-06, Amendment 39-17867, (79 FR 34403, June 17, 2014) (``AD 2014-12-06'')): Within 50 flight cycles after July 2, 2014.
(2) For airplanes that have accumulated 18,000 flight cycles or more, but fewer than 30,000 flight cycles since the airplane's first flight as of July 2, 2014 (the effective date of AD 2014-12-06): Within 275 flight cycles after July 2, 2014.
(3) For airplanes that have accumulated fewer than 18,000 flight cycles since the airplane's first flight as of July 2, 2014 (the effective date of AD 2014-12-06): Before exceeding 18,275 flight cycles since the airplane's first flight.

(h) Retained Optional Terminating Action, With No Changes

This paragraph restates the provisions of paragraph (h) of AD 2016-20-11, with no changes. Accomplishment of a high frequency eddy current (HFEC) inspection for cracking, in accordance with Airbus AOT A53W005-14, dated April 22, 2014; or AOT A53W005-14, Revision 01, dated April 29, 2014; terminates the repetitive inspections required by paragraph (g) of this AD for that airplane. If any cracking is found during the HFEC inspection, before further flight, repair using a method approved by the Manager, International Section, Transport Standards Branch, FAA; or the European Aviation Safety Agency (EASA); or Airbus's EASA Design Organization Approval (DOA).

(i) Retained Reporting Requirement, With No Changes

This paragraph restates the requirements of paragraph (i) of AD 2016-20-11, with no changes. Submit a report of the findings (both positive and negative) of the inspection required by paragraph (g) of this AD to ``Airbus Service Bulletin Reporting Online Application'' on Airbus World (https://w3.airbus.com/), at the applicable time specified in paragraph (i)(1) or (i)(2) of this AD. The report must include the inspection results, including no findings.
(1) If the inspection was done on or after January 3, 2017 (the effective date of AD 2016-20-11): Submit the report within 30 daysafter the inspection.
(2) If the inspection was done before January 3, 2017 (the effective date of AD 2016-20-11): Submit the report within 30 days after January 3, 2017.

(j) Retained Definition of Airplane Groups, With No Changes

This paragraph restates the definitions specified in paragraph (j) of AD 2016-20-11, with no changes. Paragraphs (k)(1), (k)(2), and (k)(3) of this AD refer to airplane groups, as identified in paragraphs (j)(1), (j)(2), and (j)(3) of this AD.
(1) Airplanes on which an HFEC inspection was accomplished as specified in Airbus AOT A53W005-14.
(2) Airplanes on which no HFEC inspection was accomplished as specified in Airbus AOT A53W005-14, that have accumulated more than 18,000 total flight cycles as of January 3, 2017 (the effective date of AD 2016-20-11).
(3) Airplanes on which no HFEC inspection was accomplished as specified in Airbus AOT A53W005-14, that have accumulated 18,000 total flight cycles or fewer as of January 3, 2017 (the effective date of AD 2016-20-11).

(k) Retained Repetitive HFEC Inspections, With No Changes

This paragraph restates the requirements of paragraph (k) of AD 2016-20-11, with no changes. At the applicable time specified in paragraph (k)(1), (k)(2), or (k)(3) of this AD: Do an HFEC inspection for fatigue cracking of the cargo door sill beam, lock fitting, and torsion box plate, in accordance with Airbus Service Bulletin A300-53-6179, dated December 12, 2014; or Airbus Service Bulletin A310-53-2139, dated December 12, 2014; as applicable. Repeat the HFEC inspection thereafter at intervals not to exceed 4,600 flight cycles.
(1) For airplanes identified in paragraph (j)(1) of this AD: Inspect within 4,600 flight cycles after the most recent HFEC inspection specified in Airbus AOT A53W005-14.
(2) For airplanes identified in paragraph (j)(2) of this AD: Inspect within 2,000 flight cycles after January 3, 2017 (the effective date of AD 2016-20-11).
(3) For airplanes identifiedin paragraph (j)(3) of this AD: Inspect before exceeding 13,000 total flight cycles since the airplane's first flight, or within 2,000 flight cycles after January 3, 2017 (the effective date of AD 2016-20-11), whichever occurs later.

(l) Retained Corrective Action, With No Changes

This paragraph restates the requirements of paragraph (l) of AD 2016-20-11, with no changes. If any crack is found during any inspection required by paragraph (g) or (k) of this AD: Before further flight, repair using a method approved by the Manager, International Section, Transport Standards Branch, FAA; or EASA; or Airbus's EASA DOA.

(m) Retained Terminating Action for Repetitive Inspections in Paragraph (g) of This AD, With No Changes

This paragraph restates the terminating action of paragraph (m)(1) of AD 2016-20-11, with no changes. For any airplane identified in paragraphs (j)(2) and (j)(3) of this AD, accomplishment of the initial inspection required by paragraph (k) of this AD terminates the repetitive inspections required by paragraph (g) of this AD.

(n) New Cargo Door Reinforcement

At the latest of the applicable times specified in paragraphs (n)(1), (n)(2), and (n)(3) of this AD: Reinforce the aft cargo door sill beam area, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A300-53-6181, Revision 01, dated July 2, 2015; or Airbus Service Bulletin A310-53-2141, Revision 01, dated July 2, 2015; as applicable.
(1) Before exceeding 19,600 flight cycles since first flight of the airplane.
(2) Within 2,300 flight cycles after the last HFEC or detailed inspection required by this AD that was accomplished before the effective date of this AD.
(3) Within 12 months after the effective date of this AD.

(o) New Terminating Action

Modification of an airplane as required by paragraph (n) of this AD constitutes terminating action for the repetitive inspections required by paragraphs (g) and (k) of this AD for themodified airplane only.

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(p) Credit for Previous Actions

This paragraph provides credit for actions required by paragraph (n) of this AD, if those actions were performed before the effective date of this AD using Airbus Service Bulletin A300-53-6181, dated June 26, 2015; or Airbus Service Bulletin A310-53-2141, dated June 26, 2015; as applicable.

(q) Other FAA AD Provisions

The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager, International Section, Transport Standards Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the International Section, send it to the attention of the person identified in paragraph (r)(2) of this AD. Information may be emailed to: 9-ANM-116-AMOC-REQUESTS@faa.gov.
(i) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.
(ii) AMOCs approved previously for AD 2016-20-11 are approved as AMOCs for the corresponding provisions of this AD.
(2) Contacting the Manufacturer: As of the effective date of this AD, for any requirement in this AD to obtain corrective actions from a manufacturer, the action must be accomplished using a method approved by the Manager, International Section, Transport Standards Branch, FAA; or EASA; or Airbus's EASA DOA. If approved by the DOA, the approval must include the DOA-authorized signature.
(3) Reporting Requirements: A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 1 hour per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.
(4) Required for Compliance (RC): Except as required by paragraph (l) of this AD: If any service information contains procedures or tests that are identified as RC, those procedures and tests must be done to comply with this AD; any procedures or tests that are not identified as RC are recommended. Those procedures and tests that are not identified as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the procedures and tests identified as RC can be done and the airplane can be put back in an airworthy condition. Any substitutions or changes to procedures or tests identified as RC require approval of an AMOC.

(r) Related Information

(1) Refer to Mandatory Continuing Airworthiness Information (MCAI) EASA AD 2017-0048, dated March 15, 2017; corrected April 20, 2017, for related information. This MCAI may be found in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0708.
(2) For more information about this AD, contact Dan Rodina, Aerospace Engineer, International Section, Transport Standards Branch, FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356; telephone 425-227-2125; fax 425-227-1149.
(3) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (s)(5) and (s)(6) of this AD.

(s) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise.
(3) The following service information was approved for IBR on July 2, 2014 (79 FR 34403, June 17, 2014).
(i) Airbus Alert Operators Transmission A53W005-14, dated April 22, 2014.
(ii) Reserved.
(4) The following service information was approved for IBR on January 3, 2017, (81 FR 85837, November 29, 2016).
(i) Airbus Alert Operators Transmission A53W005-14, Revision 01, dated April 29, 2014.
(ii) Airbus Service Bulletin A300-53-6179, dated December 12, 2014.(iii) Airbus Service Bulletin A300-53-6181, Revision 01, dated July 2, 2015.
(iv) Airbus Service Bulletin A310-53-2139, dated December 12, 2014.
(v) Airbus Service Bulletin A310-53-2141, Revision 01, dated July 2, 2015.
(5) For service information identified in this AD, contact Airbus SAS, Airworthiness Office--EAW, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email account.airworth-eas@airbus.com; Internet http://www.airbus.com.
(6) You may view this service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221.
(7) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2016-20-11, Amendment 39-18677 (81 FR 85837, November 29, 2016) (``AD 2016-20-11''). AD 2016-20-11 applied to certain Airbus Model A300-600 series airplanes; and Airbus Model A310 series airplanes. The NPRM published in the Federal Register on July 27, 2017 (82 FR 34891). The NPRM was prompted by a determination that reinforcement of the aft cargo door sill beam area is necessary to address the unsafe condition, which constitutes terminating action for the repetitive inspections. The NPRM proposed to continue to require repetitive inspections of the external area of the aft cargo door sill beam for cracking, repetitive inspections for fatigue cracking of the cargo door sill beam, lock fitting, and torsion box plate, and repair if necessary. The NPRM also proposed to require reinforcement of the aft cargo door sill beam area. We are issuing this AD toprevent fatigue cracking of the cargo door sill beam, lock fitting, and torsion box plate, which could result in the loss of the door locking function and subsequently, loss of the cargo door in flight and rapid decompression.
The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2017-0048, dated March 15, 2017; corrected April 20, 2017 (referred to after this as the Mandatory Continuing Airworthiness Information, or ``the MCAI''), to correct an unsafe condition for certain Airbus Model A300-600 series airplanes; and Airbus Model A310 series airplanes. The MCAI states:

In the frame of the widespread fatigue damage (WFD) compliance study and after an in-service occurrence, the area of the aft cargo door sill beam and adjacent structure was identified as sensitive to the fatigue loads.
This condition, if not detected and corrected, could lead to failure of multiple lock fittings, possibly resulting in loss of the cargo door in flight and consequent explosive decompression of the aeroplane.
To address this potential unsafe condition, Airbus issued Alert Operators Transmission (AOT) A53W005-14 providing inspection instructions and, consequently, EASA issued Emergency AD 2014-0097-E [which corresponded to FAA AD 2014-12-06, Amendment 39-17867, (79 FR 34403, June 17, 2014)] to require repetitive ultrasonic inspections (US) or detailed inspections (DET) of the aft cargo door sill beam area [and corrective actions if necessary].
After that [EASA] AD was issued, further analysis indicated that repetitive high frequency eddy current (HFEC) inspections needed to be introduced, and Airbus published Service Bulletin (SB) A310-53- 2139 and SB A300-53-6179 to provide instructions. Prompted by this determination, EASA issued AD 2015-0150 [which corresponded to FAA AD 2016-20-11], retaining the requirements of EASA Emergency AD 2014-0097-E, which was superseded, and required repetitive HFEC inspections of the concerned areas. The first HFEC inspection terminated the repetitive US/DET inspections. That [EASA] AD also required the inspection results to be reported.
Since that [EASA] AD was issued, Airbus developed a reinforcement modification of the aft cargo door sill beam area, and published Airbus SB A310-53-2141 and SB A300-53-6181, which were revised lately, to make this available for in-service application.
For the reasons described above, this [EASA] AD retains the requirements of EASA AD 2015-0150, which is superseded, and requires modification [reinforcement] of the aft cargo door sill beam, which constitutes terminating action for the repetitive inspections.
This [EASA] AD is re-published to correct the compliance time description in Table 4.

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-2017- 0708.

Comments

We gave the public the opportunityto participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment.

Request To Make the Mandatory Terminating Modification Optional

FedEx requested that the terminating modification in paragraph (n) of the proposed AD be made an optional action. FedEx stated that they have inspected their airplanes as required by AD 2016-20-11 and have not found any cracks during HFEC inspections. FedEx noted that they have inspected airplanes having accumulated anywhere from 12,000 total flight cycles to 40,000 total flight cycles. FedEx suggested that the modification would be necessary on less than 1 percent of inspected airplanes over the next 10 years. FedEx claimed that the modification is an unproven change that has not been subjected to full scale fatigue testing. For these reasons, FedEx argued that inspections alone will maintain safe airworthiness for the affected airplanes.
We disagree with the commenter's request. EASA, as the State of Design Authority for Airbus products, has determined an unsafe conditions exists after conducting a risk analysis taking into consideration in-service data for the worldwide fleet. We agree with EASA's risk assessment and their decision to mitigate the risk by mandating the modification in this AD. FedEx has not provided sufficient data to support their request to allow inspections in lieu of the modification. We have not changed this AD in this regard.

Request To Update the Costs for the Modification

FedEx requested that we update the labor costs for the modification in the proposed AD. FedEx stated that their labor costs for the modification will be an additional $10,000 per airplane. FedEx further noted that the modification would extend their service checks, resulting in additional out-of-service time for their airplanes and additional expenses.
We partially agree with the commenter's request. The number of work-hours to complete the modification depends on the airplane's configuration. In the NPRM, we used the 40 work-hours estimate for the configuration that requires less time to modify. We have updated this final rule to reflect work-hour costs of up to 68 hours (the estimated work-hours for the other configuration) for the required modification.
Regarding the additional costs related to extended service checks, we do not consider it appropriate to attribute the costs associated with aircraft ``downtime'' to the AD. Normally, compliance with the AD will not necessitate any additional downtime beyond that of a regularly scheduled maintenance hold. Even if additional downtime is necessary for some airplanes in some cases, we do not have sufficient information to evaluate the number of airplanes that may be affected or the amount of additional downtime that may be required. Therefore, we are unable to provide an estimate for these variable costs. We have made no further change to this final rule regarding this issue.Conclusion

We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting this AD as proposed except for minor editorial changes. We have determined that these minor changes:
Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was already proposed in the NPRM.

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Related Service Information Under 1 CFR Part 51

Airbus has issued Service Bulletin A300-53-6181, Revision 01, dated July 2, 2015; and Service Bulletin A310-53-2141, Revision 01, dated July 2, 2015. This service information describes procedures for reinforcing the aft cargo door sill beam area. These documents are distinct since they apply to different airplane models.
Airbus has also issued Service Bulletin A300-53-6179, dated December 12, 2014; and Service Bulletin A310-53-2139, dated December 12, 2014. This service information describes procedures for repetitive HFEC inspections of the cargo door sill beam, lock fitting, and torsion box plate. These documents are distinct since they apply to different airplane models.
Airbus has also issued Alert Operators Transmission AOT A53W005-14, Revision 01, dated April 29, 2014, which describes procedures for doing an ultrasonic inspection or detailed inspection of the aft cargo door sill beam external area for cracking.
This service information 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

We estimate that this AD affects 75 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:

Estimated Costs ----------------------------------------------------------------------------------------------------------------
Cost on U.S.
ActionLabor cost Parts cost Cost per product operators ---------------------------------------------------------------------------------------------------------------- Inspection (retained action 12 work-hours x $85 per N/A $1,020 per $76,500 per
from AD 2016[dash]20[dash]11). hour = $1,020 per inspection cycle. inspection cycle.
inspection cycle. Modification (new action)...... Up to 68 work-hours x $96,890 Up to $102,670.... Up to $7,700,250.
$85 per hour = $5,780. Reporting (retained action from 1 work hour x $85 per $0 $85 per inspection $6,375 per
AD 2016[dash]20[dash]11). hour = $85 per cycle. inspection cycle.
inspection cycle. ----------------------------------------------------------------------------------------------------------------

We have received no definitive data that will enable us to provide cost estimates for the on-condition actions specified in this AD.

Paperwork Reduction Act

A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB control number. The control number for the collection of information required by this AD is 2120- 0056. The paperwork cost associated with this AD has been detailed in the Costs of Compliance section of this document and includes time for reviewing instructions, as well as completing and reviewing the collection of information. Therefore, all reporting associated with this AD is mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at 800 Independence Ave. SW., Washington, DC 20591, ATTN: Information Collection Clearance Officer, AES-200.

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.
This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, 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 to the Director of the System Oversight Division.

Regulatory Findings

We 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;
2. Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
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.