[Federal Register Volume 80, Number 164 (Tuesday, August 25, 2015)]
[Proposed Rules]
[Pages 51488-51491]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-20853]
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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]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company 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
certain The Boeing Company Model 777-200 series airplanes. This
proposed 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). This proposed AD would 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
proposing 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: We must receive comments on this proposed AD by October 9, 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: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed 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. 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 proposed AD, the regulatory evaluation, any comments
received, and other information. The street address for the Docket
Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will
be available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Haytham Alaidy, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6573; fax:
425-917-6590; email: [email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2015-3146;
Directorate Identifier 2014-NM-249-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 because of 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. 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
[[Page 51489]]
inspection methods. Without intervention, these cracks will grow, and
eventually compromise the structural integrity of the airplane, in a
condition known as 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.
During Model 777 fatigue testing, skin cracks were found at the
stringer S-14 lap splice. These cracks initiated at scribe lines that
were made inadvertently in production when maskant was removed from the
skin panels. This condition, if not corrected, could result in fatigue
cracking of the skin lap splices, and consequent reduced structural
integrity of the airplane and could cause sudden decompression and the
inability to sustain limit flight and pressure loads.
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 and
repairs, modification to the skin lap splices; and 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 of this NPRM.
Other Related Service Information
Boeing Alert Service Bulletin 777-53A0052, dated October 10, 2014,
specifies concurrent accomplishment of an inspection of the fuselage
skin for external scribe lines, skin cracks, and repair, which are
described in Boeing Service Bulletin 777-53A0054, Revision 1, dated
November 4, 2010. The actions described in Boeing Service Bulletin 777-
53A0054, Revision 1, dated November 4, 2010, are required by AD 2013-
07-11, Amendment 39-17415 (78 FR 22185, April 15, 2013); therefore,
those actions are not required in this NPRM.
Boeing Alert Service Bulletin 777-53A0052, dated October 10, 2014,
describes doing inspections for cracks in the skin of the stringer lap
splices and repair, which are also described in Boeing Alert Service
Bulletin 777-53A0043, dated November 9, 2011. The actions described in
Boeing Alert Service Bulletin 777-53A0043, dated November 9, 2011, are
required by AD 2012-14-03, Amendment 39-17117 (77 FR 42962, July 23,
2012); therefore, those actions are not required in this NPRM.
FAA's Determination
We are proposing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
Proposed AD Requirements
This proposed AD would require accomplishing the actions specified
in the service information described previously, except as discussed
under ``Differences Between this Proposed AD and the Service
Information.'' Refer to Boeing Alert Service Bulletin 777-53A0052,
dated October 10, 2014, for information on the procedures and
compliance times.
The phrase ``corrective actions'' is used in this proposed AD.
``Corrective actions'' are actions that correct or address any
condition found. Corrective actions in an AD could include, for
example, repairs.
Explanation of Compliance Time
The compliance time for the modification specified in this proposed
AD for addressing WFD was established to ensure that discrepant
structure is modified before WFD develops in airplanes. Standard
inspection techniques cannot be relied on to detect WFD before it
becomes a hazard to flight. We will not grant any extensions of the
compliance time to complete any AD-mandated service bulletin related to
WFD without extensive new data that would substantiate and clearly
warrant such an extension.
Differences Between This Proposed AD and the Service Information
The service bulletin specifies to contact the manufacturer for
instructions on how to repair certain conditions, but this proposed AD
would require repairing those conditions in one of the following ways:
In accordance with a method that we approve; or
Using data that meet the certification basis of the
airplane, and that have been approved by the Boeing Commercial
Airplanes Organization Designation Authorization (ODA) whom we have
authorized to make those findings.
Explanation of ``RC (Required for Compliance)'' Steps in Service
Information
The FAA worked in conjunction with industry, under the
Airworthiness Directive Implementation Aviation Rulemaking Committee
(ARC), to enhance the AD system. One enhancement was a new process for
annotating which steps in the service information are required for
compliance with an AD. Differentiating these steps from other tasks in
the service information is expected to improve an owner's/operator's
understanding of crucial AD requirements and help provide consistent
judgment in AD compliance. The steps identified as RC (required for
compliance) in any service information identified previously have a
direct effect on detecting, preventing, resolving, or eliminating an
identified unsafe condition.
For service information that contains steps that are labeled as
Required for Compliance (RC), the following provisions apply: (1) 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
[[Page 51490]]
AD, and an AMOC is required for any deviations to RC steps, including
substeps and identified figures; and (2) 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.
Costs of Compliance
We estimate that this proposed AD affects 21 airplanes of U.S.
registry.
We estimate the following costs to comply with this proposed AD:
Estimated Costs
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Action Labor cost Parts cost Cost per product Cost on U.S. operators
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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 inspection cycle.
per hour = $118,235 inspection cycle.
per inspection cycle.
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We have received no definitive data that would enable us to provide
cost estimates for the on-condition actions specified in this proposed
AD.
According to the manufacturer, some of the costs of this proposed
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
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):
The Boeing Company: Docket No. FAA-2015-3146; Directorate Identifier
2014-NM-249-AD.
(a) Comments Due Date
We must receive comments by October 9, 2015.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 777-200 series
airplanes, certified 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 (DAH) indicating that the skin lap splices at certain
stringers in certain fuselage sections are subject to widespread
fatigue damage (WFD). 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 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 lap splice
[[Page 51491]]
between fuselage station 655 and station 1434 that has a scribe line
0.001 inch or deeper.
(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 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-14L/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 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-14L/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 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-14L/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)(1) 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 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. For a repair method to be approved, the repair 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
(1) For more information about this AD, contact Haytham Alaidy,
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO,
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6573;
fax: 425-917-6590; email: [email protected].
(2) For 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. 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.
Issued in Renton, Washington, on August 17, 2015.
Kevin Hull,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2015-20853 Filed 8-24-15; 8:45 am]
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