AD 2018-23-05

We are adopting a new airworthiness directive (AD) for certain Airbus SAS Model A350-941 and -1041 airplanes. This AD was prompted by a report of a close gap between the wing lower cover (WLC) and wing rib feet. This AD requires revising the operator's minimum equipment list (MEL) to change certain MEL items. This AD also requires an inspection for discrepancies and structural damage of certain wing rib foot locations, and related investigative and corrective actions if necessary. We are issuing this AD to address the unsafe condition on these products.

Final rule; request for comments.

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 adding the following new airworthiness directive (AD):

2018-23-05 Airbus SAS: Amendment 39-19491; Docket No. FAA-2018-0958; Product Identifier 2018-NM-139-AD.

(a) Effective Date

This AD becomes effective November 23, 2018.

(b) Affected ADs

None.

(c) Applicability

This AD applies to the Airbus SAS airplanes, certificated in any category, identified in paragraphs (c)(1) and (c)(2) of this AD.
(1) Model A350-941 airplanes, manufacturer serial numbers (MSNs) 203, 205, 208, 209, 210, 212, 213, 218, 219, 221, 227, 228, and 235.
(2) Model A350-1041 airplanes, MSN 188.

(d) Subject

Air Transport Association (ATA) of America Code 57, Wings.

(e) Reason

This AD was prompted by a report of a close gap between the wing lower cover (WLC) and wing rib feet. We are issuing this AD to address potential contact between the WLC and wing rib feet, which, combined with an empty fuel tank or fuel level below the wing rib foot area, could create an ignition source for the fuel vapor inside the tanks. In case of a lightning strike of high intensity in the immediate area, this condition could possibly result in ignition of the fuel-air mixture in the affected fuel tank and consequent loss of the airplane.

(f) Compliance

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

(g) Minimum Equipment List (MEL) Revision

Within 30 days after the effective date of this AD, revise the operator's MEL to prohibit dispatch of the airplane with any inoperative MEL item listed in figure 1 to paragraphs (g) and (i) of thisAD. 4910-13-P

------------------------------------------------------------------------
Sequence No. Item ------------------------------------------------------------------------ 21-09-01............................... AIR OVHT ON FUEL INERTING 1(2)
Message. 21-09-03............................... AIR PRESS LO ON FUEL INERTING
1(2) Message. 21-50-01............................... Air conditioning Pack. 21-50-02C.............................. Pack 1 Valve--Both valves
inoperative. 21-50-03C.............................. Pack 2 Valve--Both valves
inoperative. 21-50-04B.............................. Pack Flow Sensor--Both sensors
inoperative on the same pack. 21-50-07C.............................. Pack Ram Air Inlet Door--
Associated pack considered
inoperative. 21-50-08A.............................. Pack Ram Air Outlet Door--
Failed open. 21-50-08C.............................. Pack Ram Air Outlet Door--
Associated pack considered
inoperative. 21-50-09B.............................. Pack Control Channel--Both
channels inoperative. 21-58-01............................... Fuel Inerting Inlet Valve. 21-58-02............................... Fuel Inerting Inlet Valve Flap. 21-58-03............................... Fuel Inerting Ram Air Outlet
Flap. 21-58-04............................... Fuel Inerting Temperature
Control Valve. 21-58-05............................... Fuel Inerting Turbine Valve. 21-60-02C.............................. Hot Air Valve--Associated pack
valves deactivated. 36-11-01............................... Engine Bleed Air System. 36-11-02............................... Engine Bleed Valve. 36-11-03............................... Engine Bleed Fan Air Valve. 36-11-04............................... Engine Bleed Overpressure
Valve. 36-11-05A.............................. Engine Bleed IP Check Valve--
Associated Bleed Considered
Inoperative. 36-11-09............................... Engine Bleed Control. 36-11-10............................... Engine Bleed Monitoring. 36-11-11............................... Engine Bleed Monitoring and
Control. 36-11-12............................... Engine Bleed Temperature
Redundancy. 42-11-06............................... CPIOM H43. 42-11-07............................... CPIOM H44. 42-41-16............................... CRDC B01. 42-41-17............................... CRDC B02. 42-41-18............................... CRDC B03. 42-41-20............................... CRDC B05. 42-41-21............................... CRDC B06. 47-10-01............................... FTIS. ------------------------------------------------------------------------

[[Page 55816]]

BILLING CODE 4910-13-C

(h) Inspection

Within 3 months after the effective date of this AD, accomplish a detailed inspection to detect discrepancies and structural damage at the wing rib foot locations specified in, and in accordance with Airbus Alert Operators Transmission A57P011-18, dated October 8, 2018.
(1) If any discrepancy is detected, do all applicable related investigative and corrective actions before further flight, in accordance with Airbus Alert Operators Transmission A57P011-18, dated October 8, 2018.
(2) If any structural damage is detected, before further flight obtain corrective actions approved by the Manager, International Section, Transport Standards Branch, FAA; or the European Aviation Safety Agency (EASA); or Airbus SAS's EASA Design Organization Approval (DOA) and accomplish the corrective actions within the compliance time specified therein. If approved by the DOA, the approval must include the DOA-authorized signature.

(i) Relief From MEL Restrictions

After accomplishment of the inspection and all applicable related investigative and corrective actions required by paragraph (h) of this AD on an operator's fleet, the MEL revision specified in paragraph (g) of this AD is no longer required by this AD, and the provisions for relief for the affected MEL items in figure 1 to paragraphs (g) and (i) of this AD may be restored, provided those items are not otherwise restricted by the existing master minimum equipment list (MMEL).

(j) Reporting Provisions

Although Airbus Alert Operators Transmission A57P011-18, dated October 8, 2018, specifies sending inspection results to Airbus, this AD does not require a report.

(k) 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, sendit to the attention of the person identified in paragraph (l)(2) of this AD. Information may be emailed to 9-ANM-116-AMOC-REQUESTS@faa.gov. 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.
(2) Contacting the Manufacturer: 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 SAS's EASA DOA. If approved by the DOA, the approval must include the DOA- authorized signature.
(3) Required for Compliance (RC): 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.

(l) Related Information

(1) Refer to Mandatory Continuing Airworthiness Information (MCAI) EASA AD 2018-0220, dated October 12, 2018, 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-2018-0958.
(2) For more information about this AD, contact Kathleen Arrigotti, Aerospace Engineer, International Section, Transport Standards Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone and fax 206-231-3218.

(m) Material Incorporated by Reference

(1) The Director of theFederal 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.
(i) Airbus Alert Operators Transmission A57P011-18, dated October 8, 2018.
(ii) [Reserved]
(3) For service information identified in this AD, contact Airbus SAS, Airworthiness Office--EAL, Rond-Point Emile Dewoitine No: 2, 31700 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 45 80; email continued-airworthiness.a350@airbus.com; internet http://www.airbus.com.
(4) You may view this service information at the FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195.
(5) 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

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2018-0220, dated October 12, 2018 (referred to after this as the Mandatory Continuing Airworthiness Information, or ``the MCAI''), to correct an unsafe condition for certain Airbus SAS Model A350-941 and - 1041 airplanes. The MCAI states:

A deviation was identified on certain A350 aeroplanes, where a gap check between some wing rib feet and the wing lower cover (WLC) was not systematically performed. Due to tolerance build-up during wing manufacture, close gap between the WLC and wing rib feet could occur in some locations. Under some flight loading conditions, intermittent or permanent contact may occur.
This condition, if not detected and corrected, combined with an empty fuel tank or fuel level below the rib foot area, could create an ignition source for the fuel vapour inside the tanks which, in case of a lightning strike of high intensity in the immediate area, could possibly result in ignition of the fuel-air mixture in the affected fuel tank and consequent loss of the aeroplane.
To address this potential unsafe condition, Airbus issued the AOT [Alert Operators Transmission A57P011-18] to provide inspection instructions, and an MER [major event revision] of the A350 MMEL [master minimum equipment list] that incorporates temporary restrictions of the MMEL items related to the fuel tank inerting system.
For the reasons described above, this [EASA] AD requires implementation of certain dispatch restrictions. This [EASA] AD also requires a one-time detailed inspection (DET) of the affected areas and, depending on findings, accomplishment of applicable corrective action(s). No findings, or accomplishment of [related investigative and] corrective action(s), as applicable, allows removal of the MMEL restrictions.
This [EASA] AD is considered to be an interim actionand further [EASA] AD action may follow.

The inspection is intended to detect structural damage as well as other discrepancies including missing sealant at each wing rib foot location and a close gap between the wing rib foot and the WLC inboard and outboard side of the rib.
You may examine the MCAI on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018- 0958.

Related Service Information Under 1 CFR Part 51

Airbus has issued Alert Operators Transmission A57P011-18, dated October 8, 2018, which describes procedures for a detailed inspection and related investigative and corrective actions. Related investigative actions include a gap check. Corrective actions include rework of the wing rib foot and repair. This service information is reasonably available because the interested parties have access to it

[[Page 55814]]

through their normal course of business or by the means identified in the ADDRESSES section.

FAA'sDetermination

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

Requirements of This AD

This AD revises the operator's MEL to change certain MEL items. This AD also requires an inspection for discrepancies and structural damage of certain wing rib foot locations, and related investigative and corrective actions if necessary.

Differences Between This AD and the MCAI

The MCAI specifies to revise the MMEL to change certain MMEL items. This AD refers to the operator's MEL instead of the MMEL. It is unnecessary to reference the MMEL, as operators are required in 14 CFR part 91 to have an MEL to operate with inoperable equipment and provisions for relief cannot be in an MEL without first being part of the MMEL. The intent of the provision has not changed.

FAA's Justification and Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because contact between the WLC and wing rib feet, combined with an empty fuel tank or fuel level below the wing rib foot area, could create an ignition source for the fuel vapor inside the tanks. In case of a lightning strike of high intensity in the immediate area, this condition could possibly result in ignition of the fuel-air mixture in the affected fuel tank and consequent loss of the airplane. Therefore, we find good cause that notice and opportunity for prior public comment are impracticable. In addition, for the reasons stated above, we find that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment. We invite you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include ``Docket No. FAA-2018-0958; Product Identifier 2018-NM-139-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD based on those comments.
We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information youprovide. We will also post a report summarizing each substantive verbal contact we receive about this AD.

Costs of Compliance

We estimate that this AD affects 1 airplane of U.S. registry. We estimate the following costs to comply with this AD:

Estimated Costs for Required Actions ----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- 60 work-hours x $85 per hour = $5,100........................ $0 $5,100 $5,100 ----------------------------------------------------------------------------------------------------------------

We have received no definitive data that would enable us to provide cost estimates for on-condition repair of structural damage specified in this AD. We estimate the following costs to do any necessary on- condition actions that would be required to address other discrepancies based on the results of any required actions.

Estimated Costs of On-Condition Actions ------------------------------------------------------------------------
Cost per
Labor cost Parts cost product ------------------------------------------------------------------------ 10 work-hours x $85 per hour = $850... $0 $850 ------------------------------------------------------------------------

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 and associated appliances to the Director of the System Oversight Division.

[[Page 55815]]

RegulatoryFindings

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.