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[Federal Register Volume 80, Number 108 (Friday, June 5, 2015)]
[Proposed Rules]
[Pages 32063-32066]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-13342]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-1422; Directorate Identifier 2014-NM-125-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 supersede Airworthiness Directive (AD) 98-18-26, 
for certain Airbus Model A320 series airplanes. AD 98-18-26 currently 
requires repetitive inspections to detect fatigue cracking of the front 
spar vertical stringers on the wings; and repair, if necessary. Since 
we issued AD 98-18-26, we have received reports that indicate new 
repetitive inspections having new thresholds and intervals are needed 
and that additional work is needed to accomplish the inspections on 
airplanes on which a previous modification has been accomplished. This 
proposed AD would require repetitive high frequency eddy current (HFEC) 
inspections for cracking of the radius of the front spar vertical 
stringers and the horizontal floor beam on frame 36, and a rototest 
inspection for cracking of the fastener holes of the front spar 
vertical stringers on frame 36, and repair if necessary. We are 
proposing this AD to detect and correct fatigue cracking of the front 
spar vertical stringers on the wings, which could result in the reduced 
structural integrity of the airframe.

DATES: We must receive comments on this proposed AD by July 20, 2015.

ADDRESSES: You may send comments 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-
1422; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday,

[[Page 32064]]

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-2015-1422; 
Directorate Identifier 2014-NM-125-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

    On August 28, 1998, we issued AD 98-18-26, Amendment 39-10742 (63 
FR 47423, September 8, 1998). AD 98-18-26 requires repetitive 
inspections to detect fatigue cracking of the front spar vertical 
stringers on the wings, which could result in the reduced structural 
integrity of the airframe on certain Airbus Model A320 series 
airplanes. AD 98-18-26 contains a modification that provides a 
terminating action for the repetitive inspection requirements.
    Since we issued AD 98-18-26, Amendment 39-10742 (63 FR 47423, 
September 8, 1998), we have received reports that indicate new 
repetitive inspections having new thresholds and intervals are needed 
and that additional work is needed to accomplish the inspections on 
airplanes where shims were installed under the heads of 2 fasteners at 
the top end of the front spar vertical stringers using Airbus Service 
Bulletin A320-57-1017, dated September 3, 1991; or Airbus Service 
Bulletin A320-57-1017, Revision 01, dated March 17, 1997, or on which 
modification 21290P1546 was accomplished during production.
    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Union, has issued EASA 
Airworthiness Directive 2014-0069, dated March 19, 2014 (referred to 
after this as the Mandatory Continuing Airworthiness Information, or 
``the MCAI''), to correct an unsafe condition on certain Airbus Model 
A320-211, -212, and -231 airplanes. The MCAI states:

    During center fuselage certification full scale fatigue test, 
cracks were found on the front vertical stringer at frame 36. 
Analysis of these findings indicated that a number of in-service 
aeroplanes could be similarly affected.
    This condition, if not detected and corrected, could lead to 
crack propagation and consequent deterioration of the structural 
integrity of the aeroplane.
    To address this potential unsafe condition, [Directorate General 
for Civil Aviation] DGAC France AD 97-311-105 [which corresponds to 
FAA AD 98-18-26, Amendment 39-10742 (63 FR 47423, September 8, 
1998)] was issued to require repetitive [HFEC] inspections [for 
cracking] in accordance with the instruction of Airbus Service 
Bulletin (SB) A320-57-1016. At the same time, the modification 
provided by Airbus SB A320-57-1017 was considered to be terminating 
action for the repetitive inspections required by DGAC France AD 97-
311-105.
    Since that [DGAC] AD was issued, and following new analysis, 
modification per Airbus SB A320-57-1017 is no longer considered to 
be terminating action for the repetitive inspections as required by 
DGAC France AD 97-311-105.
    Aeroplanes with [manufacturer serial number] MSN 0080 up to 0155 
inclusive have been delivered with the addition of a 5 [millimeter] 
mm thick light alloy shim under the heads of 2 fasteners at the top 
end of the front spar vertical stringers (Airbus modification 
21290P1546, which is the production line equivalent to in-service 
modification through Airbus SB A320-57-1017). From MSN 0156 and 
higher, all aeroplanes are delivered with vertical stiffeners of the 
forward wing spar upper end with stiffener cap thickness increased 
from 4 to 6 mm (Airbus modification 21290P1547).
    Prompted by these findings, Airbus issued SB A320-57-1178 to 
introduce new repetitive inspections with new thresholds and 
intervals.
    For the reasons described above, DGAC France AD 97-311-105 is 
superseded and this [EASA] AD requires the repetitive inspections at 
new thresholds and intervals.
    After EASA issued [proposed airworthiness directive] PAD 14-021, 
it was discovered that additional work [HFEC inspections for 
cracking of the radius of spar vertical stringers and horizontal 
beam in the center fuselage of frame 36, and a rototest inspection 
for cracking of the fastener holes of the spar vertical stringers 
radius on Frame 36 and repair if necessary], to be included in 
Revision 01 of Airbus SB A320-57-1178, is required to accomplish the 
inspections. This Final [EASA] AD has been amended accordingly.

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-
1422.

Related Service Information Under 1 CFR Part 51

    Airbus has issued Service Bulletin A320-57-1178, Revision 01, 
including Appendix 01, dated May 28, 2014. The service information 
describes procedures for inspecting the radius of the front spar 
vertical stringers and the horizontal floor beam on frame 36 for 
cracking. 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 the same 
type design.

Differences Between This Proposed AD and the MCAI or Service 
Information

    Although EASA AD 2014-0069, dated March 19, 2014, specifies to 
accomplish an HFEC inspection for cracking of the vertical stiffeners 
radius, this proposed AD would require accomplishing an HFEC inspection 
for cracking of the radius of the front spar vertical stringers, since 
Airbus Service Bulletin A320-57-1178, Revision 01, Appendix 01, dated 
May 28, 2014, specifies the inspection is of the front spar vertical 
stringers.

Costs of Compliance

    We estimate that this proposed AD affects 17 airplanes of U.S. 
registry.
    We also estimate that it would take about 24 work-hours per product 
to comply with the basic requirements of this proposed AD. The average 
labor

[[Page 32065]]

rate is $85 per work-hour. Based on these figures, we estimate the cost 
of this proposed AD on U.S. operators to be $34,680, or $2,040 per 
product.
    In addition, we estimate that any necessary follow-on actions would 
take about 49 work-hours and require parts costing $1,210, for a cost 
of $5,375 per product. We have no way of determining the number of 
aircraft that might need this action.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation 
Programs,'' describes in more detail the scope of the Agency's 
authority.
    We are issuing this rulemaking under the authority described in 
``Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory 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 removing Airworthiness Directive (AD) 
98-18-26, Amendment 39-10742 (63 FR 47423, September 8, 1998), and 
adding the following new AD:

Airbus: Docket No. FAA-2015-1422; Directorate Identifier 2014-NM-
125-AD.

(a) Comments Due Date

    We must receive comments by July 20, 2015.

(b) Affected ADs

    This AD replaces AD 98-18-26, Amendment 39-10742 (63 FR 47423, 
September 8, 1998).

(c) Applicability

    This AD applies to Airbus Model A320-211, -212, and -231 
airplanes, certificated in any category, manufacturer serial numbers 
0001 through 0155 inclusive.

(d) Subject

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

(e) Reason

    This AD was prompted by cracks found on the front vertical 
stringer at frame 36. This AD was also prompted by reports that 
indicate new repetitive inspections having new thresholds and 
intervals are needed and that additional work is needed to 
accomplish the inspections on airplanes on which a previous 
modification has been accomplished. We are issuing this AD to detect 
and correct fatigue cracking of the front spar vertical stringers on 
the wings, which could result in the reduced structural integrity of 
the airframe.

(f) Compliance

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

(g) Inspections

    Within the applicable compliance times specified in paragraphs 
(h)(1) through (h)(4) of this AD, do a high frequency eddy current 
(HFEC) inspection for cracking of the radius of the front spar 
vertical stringers and the horizontal floor beam on frame 36, and do 
a rototest inspection for cracking of the fastener holes of the 
front spar vertical stringers on frame 36, in accordance with the 
Accomplishment Instructions of Airbus Service Bulletin A320-57-1178, 
Revision 01, including Appendix 01, dated May 28, 2014. Repeat the 
inspections thereafter at the compliance times specified in 
paragraphs (g)(1) and (g)(2) of this AD.
    (1) For Configuration 1 airplanes identified in paragraph (h)(1) 
of this AD: At intervals not to exceed 8,800 flight cycles or 17,700 
flight hours, whichever occurs first.
    (2) For Configuration 2, 3, and 4 airplanes identified in 
paragraphs (h)(2) through (h)(4) of this AD: At intervals not to 
exceed 24,900 flight cycles or 49,800 flight hours, whichever occurs 
first.

(h) Compliance Times for Initial Inspections Required by Paragraph (g) 
of This AD

    Do the initial inspections required by paragraph (g) of this AD 
within the applicable compliance times specified in paragraphs 
(h)(1) through (h)(4) of this AD.
    (1) For Configuration 1 airplanes, having manufacturer serial 
number (MSN) 0001 though MSN 0079 inclusive, on which the 
modification specified by Airbus Service Bulletin A320-57-1017, 
dated September 3, 1991; or Airbus Service Bulletin A320-57-1017, 
Revision 01, dated March 17, 1997, has not been accomplished: At the 
later of the times specified by paragraphs (h)(1)(i) through 
(h)(1)(iii) of this AD:
    (i) The later of the times specified by paragraphs (h)(1)(i)(A) 
and (h)(1)(i)(B) of this AD:
    (A) Within 24,000 flight cycles or 48,000 flight hours, 
whichever occurs first since airplane first flight.
    (B) Within 60 days after the effective date of this AD.
    (ii) Within 8,800 flight cycles or 17,700 flight hours, 
whichever occurs first, since the last inspection specified in 
Airbus Service Bulletin A320-57-1016 was accomplished.
    (iii) Within 850 flight cycles or 1,700 flight hours, whichever 
occurs first, after the effective date of this AD, without exceeding 
14,000 flight cycles after the last inspection specified in Airbus 
Service Bulletin A320-57-1016 was accomplished.
    (2) For Configuration 2 airplanes, having MSN 0001 to 0079 
inclusive, on which the actions specified by Airbus Service Bulletin 
A320-57-1016, have not been done prior to accomplishing the actions 
specified by Airbus Service Bulletin A320-57-1017, dated September 
3, 1991; or Airbus Service Bulletin A320-57-1017, Revision 01, dated 
March 17, 1997: At the later of the times specified by paragraphs 
(h)(2)(i) and (h)(2)(ii) of this AD:
    (i) Within 8,800 flight cycles or 17,700 flight hours, whichever 
occurs first, since the modification specified in Airbus Service 
Bulletin A320-57-1017, dated September 3, 1991; or Airbus Service 
Bulletin A320-57-1017, Revision 01, dated December 6, 1995, was 
accomplished.
    (ii) Within 850 flight cycles or 1,700 flight hours, whichever 
occurs first, after the effective date of this AD.
    (3) For Configuration 3 airplanes, having MSN 0001 to 0079 
inclusive, on which the actions specified by Airbus Service Bulletin 
A320-57-1016, have been done prior to accomplishing the actions 
specified by Airbus Service Bulletin A320-57-1017, dated September 
3, 1991; or Airbus Service Bulletin A320-57-1017, Revision 01, dated

[[Page 32066]]

March 17, 1997: At the later of the times specified by paragraphs 
(h)(3)(i) and (h)(3)(ii) of this AD:
    (i) Within 24,900 flight cycles or 49,800 flight hours, 
whichever occurs first, since the modification specified in Airbus 
Service Bulletin A320-57-1017, dated September 3, 1991; or Airbus 
Service Bulletin A320-57-1017, Revision 01, dated March 17, 1997, 
was accomplished.
    (ii) Within 850 flight cycles or 1,700 flight hours, whichever 
occurs first, after the effective date of this AD.
    (4) For Configuration 4 airplanes, having MSN 0080 to 0155 
inclusive:
    At the later of the times specified in paragraphs (h)(4)(i) or 
(h)(4)(ii) of this AD:
    (i) Before exceeding 54,300 flight cycles or 108,600 flight 
hours, whichever occurs first since airplane first flight.
    (ii) Within 60 days after the effective date of this AD.

(i) Repair

    If any crack is detected during any inspection required by 
paragraph (g) of this AD: Before further flight, repair 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).

(j) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Branch, ANM-116, 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. The AMOC approval letter must 
specifically reference 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 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.

(k) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) EASA Airworthiness Directive 2014-0069, dated March 19, 2014, 
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-2015-1422.
    (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 May 18, 2015.
John P. Piccola, Jr.,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-13342 Filed 6-4-15; 8:45 am]
 BILLING CODE 4910-13-P
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