81 FR 9749 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 81, Issue 38 (February 26, 2016)

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the skin lap splices at certain stringers in certain fuselage sections are subject to widespread fatigue damage (WFD) on aging Model 777 airplanes that have accumulated at least 45,000 total flight cycles. This AD requires inspections to detect cracking of fuselage skin lap splices in certain fuselage sections, and corrective actions if necessary; modification of left-side and right-side lap splices; and post-modification repetitive inspections for cracks in the modified lap splices, and corrective actions if necessary. We are issuing this AD to detect and correct fatigue cracking of the skin lap splices, and consequent risk of sudden decompression and the inability to sustain limit flight and pressure loads.

[Federal Register Volume 81, Number 38 (Friday, February 26, 2016)]
[Rules and Regulations]
[Pages 9749-9751]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2016-03886]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-3146; Directorate Identifier 2014-NM-249-AD; 
Amendment 39-18411; AD 2016-04-17]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
The Boeing Company Model 777-200 series airplanes. This AD was prompted 
by an evaluation by the design approval holder (DAH) indicating that 
the skin lap splices at certain stringers in certain fuselage sections 
are subject to widespread fatigue damage (WFD) on aging Model 777 
airplanes that have accumulated at least 45,000 total flight cycles. 
This AD requires inspections to detect cracking of fuselage skin lap 
splices in certain fuselage sections, and corrective actions if 
necessary; modification of left-side and right-side lap splices; and 
post-modification repetitive inspections for cracks in the modified lap 
splices, and corrective actions if necessary. We are issuing this AD to 
detect and correct fatigue cracking of the skin lap splices, and 
consequent risk of sudden decompression and the inability to sustain 
limit flight and pressure loads.

DATES: This AD is effective April 1, 2016.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of April 1, 
2016.

ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Data & Services 
Management, P. O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 
206-544-5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.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. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
3146.

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-
3146; 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 AD, the regulatory evaluation, any comments received, and 
other information. The address for the Docket Office (phone: 800-647-
5527) is Docket Management Facility, U.S. Department of Transportation, 
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Eric Lin, Aerospace Engineer, Airframe 
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office (ACO), 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6412; fax: 
425-917-6590; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to certain The Boeing Company 
Model 777-200 series airplanes. The NPRM published in the Federal 
Register on August 25, 2015 (80 FR 51488) (``the NPRM''). The NPRM was 
prompted by an evaluation by the DAH indicating that the skin lap 
splices at certain stringers in certain fuselage sections are subject 
to WFD on aging airplanes (airplanes that have accumulated at least 
45,000 total flight cycles). The NPRM proposed to require inspections 
to detect cracking of fuselage skin lap splices in certain fuselage 
sections, and corrective actions if necessary; modification of left-
side and right-side lap splices; and post-modification repetitive 
inspections for cracks in the modified lap splices, and corrective 
actions if necessary. We are issuing this AD to detect and correct 
fatigue cracking of the skin lap splices, and consequent risk of sudden 
decompression and the inability to sustain limit flight and pressure 
loads.

Comments

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

Support for the NPRM

    An anonymous commenter expressed support for the NPRM.

Request To Revise WFD Criteria Definition

    Boeing requested that we revise the NPRM to specify that DAH 
analysis indicates that potential multi-site damage that could lead to 
WFD does not occur until at least 45,000 total flight cycles on aging 
Model 777 airplanes.
    We agree with the commenter's request. We have revised the SUMMARY 
and Discussion sections of this final rule and paragraph (e) of this AD 
to specify that this AD was prompted by an evaluation by the DAH 
indicating that the skin lap splices at certain stringers in certain 
fuselage sections are subject to WFD on aging Model 777 airplanes that 
have accumulated at least 45,000 total flight cycles.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously and 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.
    We also determined that these changes will not increase the 
economic

[[Page 9750]]

burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 777-53A0052, dated 
October 10, 2014. The service bulletin describes procedures for 
inspections to detect cracking of fuselage skin lap splices, 
modification to the skin lap splices, repetitive inspections for cracks 
in the modified lap splices, and repairs. 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 21 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspection and modification....  2,713 work-hours x $85               $0  $230,605..........  $4,842,705.
                                  per hour = $230,605.
Post-modification inspection...  1,391 work-hours x $85                0  $118,235 per        $2,482,935 per
                                  per hour = $118,235                      inspection cycle.   inspection cycle.
                                  per inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this AD.
    According to the manufacturer, some of the costs of this AD may be 
covered under warranty, thereby reducing the cost impact on affected 
individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all available costs in our 
cost estimate.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    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

    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 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.

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):

2016-04-17 The Boeing Company: Amendment 39-18411; Docket No. FAA-
2015-3146; Directorate Identifier 2014-NM-249-AD.

(a) Effective Date

    This AD is effective April 1, 2016.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 777-200 series 
airplanes, certificated in any category, as identified in Boeing 
Alert Service Bulletin 777-53A0052, dated October 10, 2014.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an evaluation by the design approval 
holder indicating that the skin lap splices at certain stringers in 
certain fuselage sections are subject to widespread fatigue damage 
on aging Model 777 airplanes that have accumulated at least 45,000 
total flight cycles. We are issuing this AD to detect and correct 
fatigue cracking of the skin lap splices, and consequent risk of 
sudden decompression and the inability to sustain limit flight and 
pressure loads.

(f) Compliance

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

(g) Inspections and Corrective Actions

    Except as provided by paragraph (h)(1) of this AD, at the 
applicable time specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin 777-53A0052, dated October 10, 2014: 
Do Part 1, inspection ``A,'' of the modification area for cracks; 
Part 2, inspection ``B,'' of the modification area for cracks; and 
Part 3, inspection ``C,'' of the modification area for scribe lines 
and cracks; as applicable; and do all applicable corrective actions; 
in accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 777-53A0052, dated October 10, 2014, except as 
provided by paragraph (h)(2) of this AD. Do all applicable 
corrective actions before further flight.
    (1) Inspection ``A'' includes an external phased array 
ultrasonic inspection for cracks in the lower/overlapped skin of the 
stringer S-14 left and right (L/R) lap splices between fuselage 
station 655 and station 1434, and an open hole high frequency eddy 
current (HFEC) inspection for skin cracks at the upper and lower 
fastener rows of the stringer S-14 L/R lap splices.
    (2) Inspection ``B'' includes the inspections specified in 
paragraphs (g)(2)(i) through (g)(2)(iv) of this AD.
    (i) A detailed inspection for cracks of any skin panel common to 
a stringer S-14 L/R lap splice between fuselage station 655 and 
station 1434 that has a scribe line 0.001 inch or deeper.

[[Page 9751]]

    (ii) Either an ultrasonic inspection or a surface HFEC 
inspection for cracks (depending on the location of the scribe 
line(s)) of any skin panel common to a stringer S-14 L/R lap splice 
between fuselage station 655 and station 1434 that has a scribe line 
0.001 inch or deeper.
    (iii) An external phased array ultrasonic inspection for cracks 
in the lower/overlapped skin of the stringer S-14 L/R lap splices 
between fuselage station 655 and station 1434.
    (iv) An open hole HFEC inspection for skin cracks at the upper 
and lower fastener rows of the stringer S-14 L/R lap splices.
    (3) Inspection ``C'' includes the inspections for scribe lines 
and cracks specified in paragraphs (g)(3)(i), (g)(3)(ii), and 
(g)(3)(iii) of this AD on stringer S-14 L/R lap splice between 
fuselage station 655 and station 1434 on both sides of the airplane.
    (i) A detailed inspection for scribe lines. If any scribe line 
is found during the inspection required by this paragraph, the 
actions include the inspections specified in paragraphs (g)(3)(i)(A) 
and (g)(3)(i)(B) of this AD.
    (A) A detailed inspection for cracks of the scribe line area(s).
    (B) Either an ultrasonic inspection or a surface HFEC inspection 
for cracks (depending on the location of the scribe line(s)).
    (ii) An external phased array ultrasonic inspection for cracks 
in the lower/overlapped skin of the stringer S-14 L/R lap splices 
between fuselage station 655 and station 1434.
    (iii) An open hole HFEC inspection for skin cracks at the upper 
and lower fastener rows of the stringer S-14 L/R lap splices.

(h) Exceptions to Service Information Specifications

    (1) Where Paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 777-53A0052, dated October 10, 2014, specifies a 
compliance time ``after the original issue date of this service 
bulletin,'' this AD requires compliance within the specified 
compliance time ``after the effective date of this AD.''
    (2) If, during accomplishment of any inspection required by this 
AD, any condition is found for which Boeing Alert Service Bulletin 
777-53A0052, dated October 10, 2014, specifies to contact Boeing for 
special repair instructions or supplemental instructions for the 
modification, and specifies that action as ``RC'' (Required for 
Compliance): Before further flight, do the repair or modification 
using a method approved in accordance with the procedures specified 
in paragraph (k) of this AD.

(i) Lap Splice Modification

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 777-53A0052, dated 
October 10, 2014: Do the left-side and right-side lap splice 
modification, in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin 777-53A0052, dated October 10, 2014, 
except as provided by paragraph (h)(2) of this AD.

(j) Post-Modification Inspections and Corrective Action

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 777-53A0052, dated 
October 10, 2014: Do a post-modification internal surface HFEC 
inspection for skin cracks in the modified lap splices on both sides 
of the airplane; and do all applicable corrective actions; in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 777-53A0052, dated October 10, 2014, except as 
provided by paragraph (h)(2) of this AD. Do all applicable 
corrective actions before further flight. Repeat the inspection of 
the modified lap splices thereafter at the applicable intervals 
specified in paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 777-53A0052, dated October 10, 2014.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle Aircraft Certification Office (ACO), 
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 manager of the ACO, send it to the 
attention of the person identified in paragraph (l) of this AD. 
Information may be emailed to: [email protected].
    (2) 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.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by the Boeing Commercial Airplanes Organization 
Designation Authorization (ODA) that has been authorized by the 
Manager, Seattle ACO, to make those findings. To be approved, the 
repair method, modification deviation, or alteration deviation must 
meet the certification basis of the airplane, and the approval must 
specifically refer to this AD.
    (4) Except as required by paragraph (h)(2) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (k)(4)(i) and 
(k)(4)(ii) apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. An AMOC is required for any deviations to RC steps, 
including substeps and identified figures.
    (ii) Steps not labeled 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 RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(l) Related Information

    For more information about this AD, contact Eric Lin, Aerospace 
Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 1601 Lind 
Avenue SW., Renton, WA 98057-3356; phone: 425-917-6412; fax: 425-
917-6590; email: [email protected].

(m) 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 the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin 777-53A0052, dated October 10, 
2014.
    (ii) Reserved.
    (3) For Boeing service information identified in this AD, 
contact Boeing Commercial Airplanes, Attention: Data & Services 
Management, P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; 
telephone 206-544-5000, extension 1; fax 206-766-5680; Internet 
https://www.myboeingfleet.com.
    (4) You may view this service information at 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.
    (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.

    Issued in Renton, Washington, on February 16, 2016.
Dionne Palermo,
Acting Manager,
    Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2016-03886 Filed 2-25-16; 8:45 am]
 BILLING CODE 4910-13-P