
[Federal Register Volume 82, Number 1 (Tuesday, January 3, 2017)]
[Proposed Rules]
[Pages 54-56]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-30807]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9520; Directorate Identifier 2016-NM-163-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 all 
The Boeing Company Model 777 airplanes. This proposed AD was prompted 
by reports of cracks on the underwing longerons. This proposed AD would 
require repetitive inspections of the left and right side underwing 
longerons for any crack, and related investigative and corrective 
actions if necessary. We are proposing this AD to address the unsafe 
condition on these products.

DATES: We must receive comments on this proposed AD by February 17, 
2017.

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 NPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone: 562-797-1717; 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-2016-9520.

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-2016-
9520; 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: 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: eric.lin@faa.gov.

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-2016-9520; 
Directorate Identifier 2016-NM-163-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

    We have received a report indicating that cracks have been found 
which led to an underwing longeron becoming severed. The first 
underwing longeron crack was discovered in service. An operator had 
reports of a fuel smell in the forward cargo area. During a subsequent 
investigation, a crack was found in the center wing tank that was 
attributed to the longeron crack. All models except some Model 777-200 
airplanes without a center wing tank are affected by the potential for 
a fuel leak into the forward cargo area.
    Subsequently, three more operators have reported cracks on the left 
underwing longeron. The cracks have been reported in Model 777-300ER 
and 777-200 airplanes. The cracks have been reported as early as 3,784 
flight cycles and 31,240 flight hours. As the cracks grow in the 
longeron, further cracking has been reported and three operators noted 
the lower front spar chord had cracked. This condition, if not 
corrected, could result in fuel leakage into the forward cargo area and 
consequent increased risk of a fire or, in a more severe case, could 
adversely affect the structural integrity of the airplane.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016 (``ASB 777-53A0081, Revision 0''). The service 
information describes procedures for repetitive detailed inspections, 
ultrasonic inspections, and high frequency eddy current (HFEC) 
inspections of the left and right side longerons, and related 
investigative and corrective actions if necessary. 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.

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

[[Page 55]]

``Differences Between this Proposed AD and the Service Information.'' 
For information on the procedures and compliance times, see this 
service information at http://www.regulations.gov by searching for and 
locating Docket No. FAA-2016-9520.
    The phrase ``related investigative actions'' is used in this 
proposed AD. Related investigative actions are follow-on actions that 
(1) are related to the primary action, and (2) further investigate the 
nature of any condition found. Related investigative actions in an AD 
could include, for example, inspections.
    The phrase ``corrective actions'' is used in this proposed AD. 
Corrective actions correct or address any condition found. Corrective 
actions in an AD could include, for example, repairs.

Differences Between This Proposed AD and the Service Information

    ASB 777-53A0081, Revision 0, specifies to contact the manufacturer 
for certain instructions, but this proposed AD would require using 
repair methods, modification deviations, and alteration deviations 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.

Costs of Compliance

    We estimate that this proposed AD affects 201 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
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                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Option 1: Detailed Inspection....  4 work-hours x $85               $0  $340 per inspection  $68,340 per
                                    per hour = $340                      cycle.               inspection cycle.
                                    per inspection
                                    cycle.
Option 2: Detailed and HFEC or     12 work-hours x $85              $0  $1,020 per           $205,020 per
 Ultrasonic Inspection.             per hour = $1,020                    inspection cycle.    inspection cycle.
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
             Action                  Labor cost                Parts cost                 Cost per product
----------------------------------------------------------------------------------------------------------------
Left side or right side          102 work-hours x    $31,000 per side.............  $39,670 per side.
 longeron replacement.            $85 per hour =
                                  $8,670 per side.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions, other than the 
replacement, 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 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-2016-9520; Directorate Identifier 
2016-NM-163-AD.

[[Page 56]]

(a) Comments Due Date

    We must receive comments by February 17, 2017.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 777-200, -200LR, 
-300, -300ER, and 777F series airplanes, certificated in any 
category.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of cracks on the underwing 
longerons. We are issuing this AD to detect and correct cracks in 
the underwing longerons, which could result in fuel leakage into the 
forward cargo area and consequent increased risk of a fire or, in a 
more severe case, could adversely affect the structural integrity of 
the airplane.

(f) Compliance

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

(g) Inspections

    Except as specified in paragraph (i)(1) of this AD, at the 
applicable times specified in tables 1 through 6 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 777-53A0081, dated 
September 8, 2016 (``ASB 777-53A0081, Revision 0''): Do detailed 
inspections for any crack of the left and right side underwing 
longerons; or do detailed inspections, and high frequency eddy 
current (HFEC) or ultrasonic inspections, as applicable, for any 
crack of the left and right side underwing longerons; and do all 
applicable related investigative and corrective actions; in 
accordance with the Accomplishment Instructions of ASB 777-53A0081, 
Revision 0, except as required by paragraph (i)(2) of this AD. Do 
all applicable related investigative and corrective actions before 
further flight. Repeat the inspections thereafter at the times 
specified in tables 1 through 6 of paragraph 1.E., ``Compliance,'' 
of ASB 777-53A0081, Revision 0, as applicable. Replacing an 
underwing longeron, including doing all applicable related 
investigative and corrective actions, in accordance with the 
Accomplishment Instructions of ASB 777-53A0081, Revision 0, except 
as required by paragraph (i)(2) of this AD, terminates the 
repetitive inspections required by this paragraph for that longeron 
only.

(h) Repetitive Post-Replacement Inspections and Corrective Actions

    For airplanes on which any longeron replacement has been done as 
specified in ASB 777-53A0081, Revision 0: At the applicable times 
specified in tables 7 through 14 of paragraph 1.E., ``Compliance,'' 
of ASB 777-53A0081, Revision 0, do detailed inspections of all 
replaced longerons for any crack, or do detailed inspections and 
ultrasonic inspections of all replaced longerons for any crack, and 
do all applicable corrective actions; in accordance with the 
Accomplishment Instructions of ASB 777-53A0081, Revision 0, except 
as required by paragraph (i)(2) of this AD. Do all applicable 
corrective actions before further flight. Repeat the inspections 
thereafter at intervals not to exceed the applicable time specified 
in tables 7 through 14 of paragraph 1.E., ``Compliance,'' of ASB 
777-53A0081, Revision 0.

(i) Service Information Exceptions

    (1) Where ASB 777-53A0081, Revision 0, specifies a compliance 
time ``after the issue date of this service bulletin,'' this AD 
requires compliance within the specified compliance time after the 
effective date of this AD.
    (2) Where ASB 777-53A0081, Revision 0, specifies to contact 
Boeing for appropriate action: Before further flight, repair using a 
method approved in accordance with the procedures specified in 
paragraph (j) of this AD.

(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: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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 (i)(2) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (j)(4)(i) and 
(j)(4)(ii) of this AD 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. If a step or sub-step is labeled ``RC Exempt,'' then 
the RC requirement is removed from that step or sub-step. 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.

(k) Related Information

    (1) For more information about this AD, 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: 
eric.lin@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone: 562-797-1717; 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 December 15, 2016.
Victor Wicklund,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-30807 Filed 12-30-16; 8:45 am]
 BILLING CODE 4910-13-P


