Airworthiness Directives; The Boeing Company Airplanes

[Federal Register Volume 80, Number 148 (Monday, August 3, 2015)]
[Rules and Regulations]
[Pages 45853-45856]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-18694]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0348; Directorate Identifier 2014-NM-033-AD; 
Amendment 39-18225; AD 2015-15-15]
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, 777-200LR, 777-300ER, and 777F series 
airplanes. This AD was prompted by a report indicating that sealant 
might not have been applied in production to the wing skin panel gaps 
above certain underwing fittings. This AD would require an inspection 
for missing sealant, and applicable other specified, related 
investigative, and corrective actions. We are proposing this AD to 
detect and correct missing sealant from the wing skin panel gaps above 
the underwing fittings, which could result in corrosion and fatigue 
cracking in the wing skin panel, and consequent loss of limit load 
capability of the wing skin and potential subsequent structural failure 
of the wings.

DATES: This AD is effective September 8, 2015.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of September 8, 
2015.

ADDRESSES: 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. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA 2014-
0348.

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-2014-

[[Page 45854]]

0348; 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: Haytham Alaidy, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, WA 98057-6573; phone: 425-917-
6573; 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, 777-200LR, 777-300ER, and 777F series airplanes. The 
NPRM published in the Federal Register on July 1, 2014 (79 FR 37243). 
The NPRM was prompted by a report indicating that sealant might not 
have been applied in production to the wing skin panel gaps above 
certain underwing fittings. The NPRM proposed to require an inspection 
for missing sealant, and applicable other specified, related 
investigative and corrective actions. We are issuing this AD to detect 
and correct missing sealant from the wing skin panel gaps above the 
underwing fittings, which could result in corrosion and fatigue 
cracking in the wing skin panel, and consequent loss of limit load 
capability of the wing skin and potential subsequent structural failure 
of the wings.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM (79 
FR 37243, July 1, 2014) and the FAA's response to each comment. Boeing 
concurs with the contents of the NPRM.

Request To Accept Approved Repairs Without Need for Alternative Methods 
of Compliance (AMOC)

    FedEx requested that any FAA-approved repair be accepted without 
the requirement of obtaining an AMOC.
    We do not agree with the request. The FAA does not consider that 
any FAA-approved repair will be acceptable to repair this condition. As 
the sealant was missing from the airplane at the time of initial 
delivery, it may not have been restored in prior repairs. In addition, 
repairs may not have detected all corrosion because the repair might 
not have included the inspection information contained in Boeing 
Service Bulletin 777-57A0097, Revision 1, dated May 4, 2015.
    Repairs for this AD must be approved by the Manager, Seattle ACO, 
FAA; or by the Boeing Organization Designation Authorization (ODA) 
using FAA Form 8100-9 in accordance with the procedures specified in 
paragraph (j)(3) of this AD. We intend to delegate authority to approve 
AMOCs to the Boeing ODA for the repair approval process. In addition to 
knowledge of the unsafe condition, the Boeing ODA is knowledgeable 
about the original airplane design and compliance substantiation. We 
have not changed this AD regarding this issue.

Request To Withdraw NPRM (79 FR 37243, July 1, 2014)

    American Airlines (AAL) stated that the Boeing 777 Maintenance 
Review Board Report (MRBR) has existing inspections intended to 
identify deterioration of sealant, as well as any corrosion or 
cracking. These inspections will detect deterioration or damage to the 
fillet seal that would lead to moisture ingression to the area of 
concern. AAL therefore considers the NPRM (79 FR 37243, July 1, 2014) 
to be unwarranted.
    We disagree with the commenter's request to withdraw the NPRM (79 
FR 37243, July 1, 2014). Evaluation of the quality escapement revealed 
that, under certain environmental conditions, moisture can get trapped 
within a cavity directly under the nacelle fittings that are normally 
filled with sealant. With the presence of moisture in this cavity, the 
existing corrosion protection would degrade within an estimated ten 
years of service, and corrosion pitting would form on the stringer 
surface. Under flight loading, cracks would initiate and propagate from 
the corrosion pits until the stringer would no longer be able to 
sustain limit load, and would eventually fail. This corrosion and 
cracking would not be detected by the existing maintenance program 
prior to stringer failure. We have not changed this AD regarding this 
issue.

Request for Validated Inspection Procedures

    American Airlines (AAL) stated that accomplishing the actions 
specified in Boeing Alert Service Bulletin 777-57A0097, dated January 
10, 2014, could be detrimental to aircraft safety. According to AAL, 
any attempt at the sealant removal to do the inspection based upon the 
existing instructions in Boeing Alert Service Bulletin 777-57A0097, 
dated January 10, 2014, could potentially damage or degrade the 
protective surface finish of the wing skin or underwing fitting and 
lead to future corrosion or fatigue cracking.
    AAL stated that it attempted and failed to accomplish the 
inspection in accordance with Boeing Alert Service Bulletin 777-
57A0097, dated January 10, 2014, because access to some of the intended 
inspection areas was severely inhibited by hydraulic lines. AAL also 
stated that any sealant, if present, would have been applied to the 
entire gap, so inspection from only one side should be sufficient. In 
addition, AAL used the recommended tooling and alternate tooling as 
specified in Boeing Alert Service Bulletin 777-57A0097, dated January 
10, 2014, but experienced multiple problems with the use of this 
tooling. In addition, AAL requested that Boeing Alert Service Bulletin 
777-57A0097, dated January 10, 2014, be validated with workable tooling 
on an in-service airplane prior to any future action.
    We infer that the commenter is requesting that we delay issuance of 
the final rule pending validation of the existing procedures. We do not 
agree. AAL reported ``multiple problems with the use of this tooling,'' 
but did not describe any specific problems. However, we understand that 
the tools themselves require frequent but inexpensive replacement. We 
have determined that use of the appropriate tools and processes to 
remove the sealant from underneath the fitting should not damage the 
skin or adjacent structures.
    Boeing has performed and validated the procedures in Boeing Alert 
Service Bulletin 777-57A0097, dated January 10, 2014, on certain 
airplanes that are representative of the fleet on the flight line 
before delivery with no damage to the skin or adjacent structures. 
However, Boeing has revised Boeing Alert Service Bulletin 777-57A0097, 
dated January 10, 2014, to clarify the sealant removal process and 
tooling, to ensure that it will not damage the skin. We also discussed 
AAL's concerns with Boeing, and Boeing reported that they have provided 
AAL with assistance. Boeing is also willing to work with any other 
operator that is having difficulty implementing the SB.
    Boeing considers that the revision of Boeing Alert Service Bulletin 
777-57A0097, dated January 10, 2014, should address AAL's concerns 
about

[[Page 45855]]

the tooling and procedures for sealant removal. We have revised 
paragraphs (c), (g), (h)(1), and (h)(2) of this AD to refer to Boeing 
Service Bulletin 777-57A0097, Revision 1, dated May 4, 2015. We have 
added new paragraph (i) to this AD to give credit for actions done 
before the effective date of this AD using Boeing Alert Service 
Bulletin 777-57A0097, dated January 10, 2014. We have redesignated 
subsequent paragraphs accordingly. The FAA will consider approving 
alternative procedures if they are shown to be effective.

Request for Additional Time

    AAL requested that, once Boeing Alert Service Bulletin 777-57A0097, 
dated January 10, 2014, is validated, sufficient time should be 
provided to allow operators to procure such tooling.
    We infer that the commenter is requesting an extension to the 
compliance time. We do not agree with the commenter's request to extend 
the compliance time. We coordinated with Boeing regarding tool 
availability and fabrication. The tools stated in Boeing Service 
Bulletin 777-57A0097, dated January 10, 2014; and Revision 1, dated May 
4, 2015; are nonmetallic sealant scrapers, which are widely available, 
with no lead time to procure these tools. Existing tools may be 
modified to match the wing panel gaps by cutting them to the correct 
size. However, we do understand that cutting the tools to size may 
weaken the tools, which could cause them to fracture and result in more 
frequent replacement of the tools. Boeing has stated that there is no 
engineering or drawing work required for fabrication. Any certified 
aircraft mechanic can fabricate the necessary tools. Boeing stated that 
during validation of the Boeing Alert Service Bulletin 777-57A0097, 
dated January 10, 2014, the tools were fabricated in a working shift. 
We have not changed this AD in this regard.

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:
    <bullet> Are consistent with the intent that was proposed in the 
NPRM (79 FR 37243, July 1, 2014) for correcting the unsafe condition; 
and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM (79 FR 37243, July 1, 2014).
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Service Bulletin 777-57A0097, Revision 1, dated 
May 4, 2015. The service information describes procedures for the 
inspection and repair of underwing fitting sealant at wing panel gaps. 
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 AD.

Costs of Compliance

    We estimate that this AD affects 6 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....................  Up to 104 work-                $0  Up to $8,840            Up to $53,040.
                                 hours x $85 per
                                 hour = $8,840.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary actions that 
would be required based on the results of the inspection. We have no 
way of determining the number of aircraft that might need these 
actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                Action                          Labor cost           Parts cost           Cost per product
----------------------------------------------------------------------------------------------------------------
Sealant restoration...................  1 work-hour x $85 per                  $0  $85.
                                         hour = $85.
Corrosion inspection..................  2 work-hours x $85 per                 $0  $170 per side.
                                         hour = $170 per side.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition corrosion repair 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 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,

[[Page 45856]]

    (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):

2015-15-15 The Boeing Company: Amendment 39-18225; Docket No. FAA-
2014-0348; Directorate Identifier 2014-NM-033-AD.

(a) Effective Date

    This AD is effective September 8, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 777-200, 777-200LR, 
777-300ER, and 777F series airplanes, certificated in any category, 
as identified in Boeing Service Bulletin 777-57A0097, Revision 1, 
dated May 4, 2015.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report indicating that sealant might 
not have been applied in production to the wing skin panel gaps 
above certain underwing fittings. We are issuing this AD to detect 
and correct missing sealant from the wing skin panel gaps above the 
underwing fittings, which could result in corrosion and fatigue 
cracking in the wing skin panel, and consequent loss of limit load 
capability of the wing skin and potential subsequent structural 
failure of the wings.

(f) Compliance

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

(g) Inspection, Related Investigative and Corrective Actions

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 777-57A0097, Revision 1, 
dated May 4, 2015, except as required by paragraph (h)(1) of this 
AD: Do a detailed inspection for missing sealant in the wing skin 
panel gaps above the underwing fittings, and do all applicable other 
specified, related investigative, and corrective actions, in 
accordance with the Accomplishment Instructions of Boeing Service 
Bulletin 777-57A0097, Revision 1, dated May 4, 2015, except as 
required by paragraph (h)(2) of this AD. Do all applicable other 
specified, related investigative, and corrective actions before 
further flight.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Service Bulletin 777-57A0097, Revision 1, dated 
May 4, 2015, 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) Where Boeing Service Bulletin 777-57A0097, Revision 1, dated 
May 4, 2015, specifies to contact Boeing for appropriate action: 
Repair before further flight using a method approved in accordance 
with the procedures specified in paragraph (j) of this AD.

(i) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using Boeing Alert Service Bulletin 777-
57A0097, dated January 10, 2014.

(j) 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 (k)(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 Aircraft 
Certification Office (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) Some steps in the Work Instructions are labeled as Required 
for Compliance (RC). If this service bulletin is mandated by an AD, 
then 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. 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.

(k) 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) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (l)(3) and (l)(4) of this AD.

(l) 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 Service Bulletin 777-57A0097, Revision 1, dated May 
4, 2015.
    (ii) Reserved.
    (3) 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.
    (4) 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.
    (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 July 23, 2015.
Victor Wicklund,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-18694 Filed 7-31-15; 8:45 am]
 BILLING CODE 4910-13-P

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