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[Federal Register Volume 80, Number 187 (Monday, September 28, 2015)]
[Proposed Rules]
[Pages 58226-58229]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-24423]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-3635; Directorate Identifier 2015-NM-037-AD]
RIN 2120-AA64

Airworthiness Directives; Airbus Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
Airbus Model A318, A319, A320, and A321 series airplanes. This proposed 
AD was prompted by an evaluation by the design approval holder (DAH) 
indicating that the fuselage skin repairs are subject to widespread 
fatigue damage (WFD). This proposed AD would require an inspection to 
determine whether any fuselage external skin (doubler) repairs have 
been accomplished, an inspection for cracking of certain repaired 
external fuselage skin areas in the fuselage, and repair if necessary. 
We are proposing this AD to detect and correct fatigue cracking of the 
fuselage skin, which could result in reduced structural integrity of 
the airplane.

DATES: We must receive comments on this proposed AD by November 12, 
2015.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Airbus, Airworthiness Office--EIAS, 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. You may view this referenced service information at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. 
For information on the availability of this material at the FAA, call 
425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
3635; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Operations office (telephone 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Sanjay Ralhan, Aerospace Engineer, 
International Branch, ANM-116, Transport Airplane Directorate, FAA, 
1601 Lind Avenue SW., Renton, WA 98057-3356; telephone 425-227-1405; 
fax 425-227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2015-3635; 
Directorate Identifier 2015-NM-037-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD based on those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    Structural fatigue damage is progressive. It begins as minute 
cracks, and those cracks grow under the action of repeated stresses. 
This can happen because of normal operational conditions and design 
attributes, or because of isolated situations or incidents such as 
material defects, poor fabrication quality, or corrosion pits, dings, 
or scratches. Fatigue damage can occur locally, in small areas or 
structural design details, or globally.

[[Page 58227]]

Global fatigue damage is general degradation of large areas of 
structure with similar structural details and stress levels. Multiple-
site damage is global damage that occurs in a large structural element 
such as a single rivet line of a lap splice joining two large skin 
panels. Global damage can also occur in multiple elements such as 
adjacent frames or stringers. Multiple-site-damage and multiple-
element-damage cracks are typically too small initially to be reliably 
detected with normal inspection methods. Without intervention, these 
cracks will grow, and eventually compromise the structural integrity of 
the airplane, in a condition known as widespread fatigue damage (WFD). 
As an airplane ages, WFD will likely occur, and will certainly occur if 
the airplane is operated long enough without any intervention.
    The FAA's WFD final rule (75 FR 69746, November 15, 2010) became 
effective on January 14, 2011. The WFD rule requires certain actions to 
prevent structural failure due to WFD throughout the operational life 
of certain existing transport category airplanes and all of these 
airplanes that will be certificated in the future. For existing and 
future airplanes subject to the WFD rule, the rule requires that DAHs 
establish a limit of validity (LOV) of the engineering data that 
support the structural maintenance program. Operators affected by the 
WFD rule may not fly an airplane beyond its LOV, unless an extended LOV 
is approved.
    The WFD rule (75 FR 69746, November 15, 2010) does not require 
identifying and developing maintenance actions if the DAHs can show 
that such actions are not necessary to prevent WFD before the airplane 
reaches the LOV. Many LOVs, however, do depend on accomplishment of 
future maintenance actions. As stated in the WFD rule, any maintenance 
actions necessary to reach the LOV will be mandated by airworthiness 
directives through separate rulemaking actions.
    In the context of WFD, this action is necessary to enable DAHs to 
propose LOVs that allow operators the longest operational lives for 
their airplanes, and still ensure that WFD will not occur. This 
approach allows for an implementation strategy that provides 
flexibility to DAHs in determining the timing of service information 
development (with FAA approval), while providing operators with 
certainty regarding the LOV applicable to their airplanes.
    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Union, has issued EASA 
Airworthiness Directive 2015-0036R1, dated March 31, 2015 (referred to 
after this as the Mandatory Continuing Airworthiness Information, or 
``the MCAI''), to correct an unsafe condition on all Model A318, A319, 
A320, and A321 series airplanes. The MCAI states:

    During A320 family Extended Service Goal full scale fatigue 
tests, it was demonstrated that the inspection thresholds defined in 
the current Structural Repair Manual (SRM) for the A320 family skin 
repairs are insufficient to detect possible cracks becoming after 
repairs. The findings are limited to 1.2 [millimeter] (mm) fuselage 
skin and cover for all cut-out external repairs. The internal 
repairs are not affected.
    This condition, if not detected and corrected, could affect the 
structural integrity of the fuselage at the repaired skin area(s).
    To address this potential unsafe condition, Airbus issued Alert 
Operators Transmission (AOT) A53N007-14 to provide inspection 
instructions.
    For the reasons described above, EASA issued AD 2015-0036 
[http://www.casa.gov.au/scripts/nc.dll?WCMS:OLDASSET::svPath=/ADFiles/over/a320/,svFileName=2015-0036.pdf] to require a one-time 
inspection of the affected areas and, depending on findings, 
accomplishment of applicable repair instructions.
    Since that AD was issued, operators have questioned the 
inspection threshold for A318 aeroplanes (not yet in the Airbus 
AOT), which is actually identical to that for A319 aeroplanes. In 
addition, an error has been detected in paragraph (1), since 
external doublers may have been installed in the affected area by a 
modification that may not be recorded as repair.
    Such doubler installations are also subject to the inspection 
requirements of this AD, which is therefore revised to provide 
clarifications, correcting paragraph (1) and introducing a Note.

    Required actions include an inspection to determine whether any 
fuselage external skin (doubler) repairs have been accomplished, an 
external ultrasonic inspection or an internal low/high frequency eddy 
current inspection for cracking of certain repaired external fuselage 
skin areas in the fuselage, and repair if necessary. The compliance 
times vary depending on airplane configuration. The earliest compliance 
time is within 25,200 flight cycles since last repair, or within 350 
flight cycles after the effective date of the AD, whichever occurs 
later. The latest compliance time is within 45,000 flight cycles since 
last repair; within 1,500 flight cycles from the effective date of the 
AD, without exceeding 49,100 flight cycles since last repair; or within 
350 flight cycles since the effective date of the AD; whichever occurs 
last. 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-2015-3635.

Related Service Information Under 1 CFR Part 51

    Airbus has issued Alert Operators Transmission A53N007-14, dated 
July 22, 2014. The service information describes procedures for an 
inspection to detect cracking on repaired 1.2 millimeter fuselage skin 
areas on fuselage sections 11, 12, 13, 14, 16, and 17 at external 
doubler repairs. The actions described in this service information are 
intended to correct the unsafe condition identified in the MCAI. 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 of this NPRM.

FAA's Determination and Requirements of This Proposed AD

    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 proposing this AD because we 
evaluated all pertinent information and determined an unsafe condition 
exists and is likely to exist or develop on other products of these 
same type designs.

Costs of Compliance

    We estimate that this proposed AD affects 940 airplanes of U.S. 
registry.
    We also estimate that it would take about 2 work-hours per product 
to comply with the basic requirements of this proposed AD. The average 
labor rate is $85 per work-hour. Based on these figures, we estimate 
the cost of this proposed AD on U.S. operators to be $159,800, or $170 
per product.
    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
AD.

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:

[[Page 58228]]

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 Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify 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);
    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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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):

Airbus: Docket No. FAA-2015-3635; Directorate Identifier 2015-NM-
037-AD.

(a) Comments Due Date

    We must receive comments by November 12, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to the Airbus airplanes specified in paragraphs 
(c)(1) through (c)(4) of this AD, certificated in any category, all 
manufacturer serial numbers.
    (1) Airbus Model A318-111, -112, -121, and -122 airplanes.
    (2) Airbus Model A319-111, -112, -113, -114, -115, -131, -132, 
and -133 airplanes.
    (3) Airbus Model A320-211, -212, -214, -231, -232, and -233 
airplanes.
    (4) Airbus Model A321-111, -112, -131, -211, -212, -213, -231, 
and -232 airplanes.

(d) Subject

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

(e) Reason

    This AD was prompted by an evaluation by the design approval 
holder indicating that the fuselage skin repairs are subject to 
widespread fatigue damage. We are issuing this AD to detect and 
correct fatigue cracking of the fuselage skin, which could result in 
reduced structural integrity of the airplane.

(f) Compliance

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

(g) Inspection To Determine Repair Areas

    At the applicable time specified in paragraph (g)(1) or (g)(2) 
of this AD: Do an inspection to determine whether any fuselage 
external skin (doubler) repairs have been accomplished on fuselage 
sections 11, 12, 13, 14, 16, and 17 with a skin thickness of 1.2 
millimeters. A review of airplane maintenance records is acceptable 
in lieu of this inspection if the identification of applicable 
repairs can be conclusively determined from that review.
    (1) For Model A319, A320, and A321 series airplanes: Except as 
specified in paragraph (h)(1) and (h)(2) of this AD, at the 
applicable time specified in paragraphs 4.1.1.b., and 4.1.1.c., of 
``Accomplishment Timescale,'' of Airbus Alert Operators Transmission 
(AOT) A53N007-14, dated July 22, 2014, or within 350 flight cycles 
after the effective date of this AD, whichever occurs later.
    (2) For Model A318 series airplanes: Except as specified in 
paragraph (h)(1) and (h)(2) of this AD, at the Model A319 airplane 
time specified in paragraphs 4.1.1.b., and 4.1.1.c., of 
``Accomplishment Timescale,'' of Airbus AOT A53N007-14, dated July 
22, 2014, or within 350 flight cycles after the effective date of 
this AD, whichever occurs later.

(h) Exceptions to Service Information

    (1) Where paragraphs 4.1.1.b., and 4.1.1.c., of ``Accomplishment 
Timescale,'' of Airbus AOT A53N007-14, dated July 22, 2014, 
specifies ``FC'', this AD specifies ``flight cycles.''
    (2) Where paragraphs 4.1.1.b., and 4.1.1.c., of ``Accomplishment 
Timescale,'' of Airbus AOT A53N007-14, dated July 22, 2014, 
specifies ``from AOT issuance'', this AD specifies ``as of the 
effective date of this AD.''

(i) Inspection for Cracking

    If, during the inspection required by paragraph (g) of this AD, 
it is determined that any fuselage external skin (doubler) repair 
has been accomplished on fuselage section 11, 12, 13, 14, 16, or 17: 
At the applicable time specified paragraph (g)(1) or (g)(2) of this 
AD, do an external ultrasonic inspection (US) or an internal low 
frequency eddy current (LFEC) inspection for cracking of all of the 
repaired 1.2 millimeter (mm) fuselage skin areas, in accordance with 
the instructions specified in paragraph 4.2.2 ``Inspection 
Requirements,'' of Airbus AOT A53N007-14, dated July 22, 2014, 
except as provided by paragraph (j) of this AD.

(j) Optional Inspection for Cracking

    As an optional method of compliance to the US or LFEC inspection 
required by paragraph (i) of this AD: Do a high frequency eddy 
current (HFEC) inspection for cracking in the cut-out surrounding 
the fastener area, at and in front (approximately 10-15 millimeters) 
of the fastener row, after doubler removal and before any new 
extended doubler installation, using a method approved by the 
Manager, International Branch, ANM-116, Transport Airplane 
Directorate, FAA; or the European Aviation Safety Agency (EASA); or 
Airbus's EASA Design Organization Approval (DOA).

(k) Optional Repetitive Inspections

    In lieu of doing the inspection required by paragraph (i) of 
this AD: Within the applicable compliance time specified in 
paragraph 4.1.1 ``Accomplishment Timescale,'' of Airbus AOT A53N007-
14, dated July 22, 2014, after accomplishing the inspections 
required by paragraph (g) of this AD, do a detailed inspection or 
HFEC inspection and repeat the inspection thereafter within the 
applicable compliance times specified in paragraph 4.1.1 
``Accomplishment Timescale,'' of Airbus AOT A53N007-14, dated July 
22, 2014. The inspections must be done in accordance with the 
instructions of paragraph 4.2.2 ``Inspection Requirements,'' of 
Airbus AOT A53N007-14, dated July 22, 2014. For Model A318 series 
airplanes, use the applicable compliance times and instructions 
specified in Airbus AOT A53N007-14, dated July 22, 2014, that are 
specified for Model A319 series airplanes.

(l) Repair

    If any crack is found during any inspection required by 
paragraph (i), (j), or (k) of this AD: Before further flight, repair 
the cracking, in accordance with the instructions of paragraph 4.2.3 
``Findings,'' of Airbus AOT A53N007-14, dated July 22, 2014, except 
where Airbus AOT A53N007-14, dated July 22, 2014, specifies to 
contact Airbus for a repair design approval sheet or for further 
instructions, this AD requires repair using a method approved by the 
Manager, International Branch, ANM-116, Transport Airplane 
Directorate, FAA; or the EASA; or Airbus's EASA DOA.

(m) FAA-Approved Maintenance or Inspection Program Revision

    Concurrently with the accomplishment of any repair required by 
paragraph (l) of this

[[Page 58229]]

AD, revise the post-repair inspection threshold(s) in the applicable 
FAA-approved maintenance program or inspection program, as 
applicable, in accordance with the instructions specified in 
paragraph 4.1.1 ``Accomplishment Timescale,'' of Airbus AOT A53N007-
14, dated July 22, 2014; except for Model A318 series airplanes use 
the instructions specified for Model A319 series airplanes.

(n) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Branch, ANM-116, Transport Airplane Directorate, 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 Branch, send it to ATTN: Sanjay 
Ralhan, Aerospace Engineer, International Branch, ANM-116, Transport 
Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057-
3356; telephone 425-227-1405; fax 425-227-1149. 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 
Branch, ANM-116, Transport Airplane Directorate, FAA; or the EASA; 
or Airbus's EASA DOA. If approved by the DOA, the approval must 
include the DOA-authorized signature.

(o) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) EASA Airworthiness Directive 2015-0036R1, dated March 31, 
2015, 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-2015-3635.
    (2) For service information identified in this AD, contact 
Airbus, Airworthiness Office--EIAS, 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. You may view this service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. 
For information on the availability of this material at the FAA, 
call 425-227-1221.

    Issued in Renton, Washington, on September 16, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-24423 Filed 9-25-15; 8:45 am]
 BILLING CODE 4910-13-P
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