83 FR 8325 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 83, Issue 39 (February 27, 2018)

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the gore web lap splices of the aft pressure bulkhead are subject to widespread fatigue damage (WFD). This AD requires repetitive inspections of the gore webs, gore web lap splices, and repair webs, as applicable, of the aft pressure bulkhead, and applicable on-condition actions. We are issuing this AD to address the unsafe condition on these products.

[Federal Register Volume 83, Number 39 (Tuesday, February 27, 2018)]
[Rules and Regulations]
[Pages 8325-8328]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-03600]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0766; Product Identifier 2017-NM-046-AD; Amendment 
39-19203; AD 2018-04-08]
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 all The 
Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series 
airplanes. This AD was prompted by an evaluation by the design approval 
holder (DAH) indicating that the gore web lap splices of the aft 
pressure bulkhead are subject to widespread fatigue damage (WFD). This 
AD requires repetitive inspections of the gore webs, gore web lap 
splices, and repair webs, as applicable, of the aft pressure bulkhead, 
and applicable on-condition actions. We are issuing this AD to address 
the unsafe condition on these products.

[[Page 8326]]


DATES: This AD is effective April 3, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of April 3, 
2018.

ADDRESSES: For service information identified in this final rule, 
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 service information at the 
FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. 
For information on the availability of this material at the FAA, call 
206-231-3195. It is also available on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-
0766.

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-2017-
0766; 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 final rule, 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: George Garrido, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5232; fax: 562-627-
5210; 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 all The Boeing Company 
Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. The 
NPRM published in the Federal Register on August 11, 2017 (82 FR 
37546). The NPRM was prompted by an evaluation by the DAH indicating 
that the gore web lap splices of the aft pressure bulkhead are subject 
to WFD. The NPRM proposed to require repetitive inspections of the gore 
webs, gore web lap splices, and repair webs, as applicable, of the aft 
pressure bulkhead, and applicable on-condition actions.
    We are issuing this AD to detect and correct cracking in the gore 
webs, gore web lap splices, and repair webs of the aft pressure 
bulkhead, which could result in possible rapid decompression and loss 
of structural integrity.

Comments

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

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that accomplishing the Supplemental 
Type Certificate (STC) ST01219SE does not affect the actions specified 
in the NPRM.
    We concur with the commenter. We have redesignated paragraph (c) of 
the proposed AD as paragraph (c)(1) of this AD and added paragraph 
(c)(2) to this AD to state that installation of STC ST01219SE does not 
affect the ability to accomplish the actions required by this AD. 
Therefore, for airplanes on which STC ST01219SE is installed, a 
``change in product'' alternative method of compliance (AMOC) approval 
request is not necessary to comply with the requirements of 14 CFR 
39.17.

Request To Clarify ``Related AD'' Section

    Boeing recommended that a statement be added to the ``Related AD'' 
section of the NPRM to provide clarification of the effect of the 
proposed AD on the requirements of paragraph (o) of AD 2012-18-13 R1, 
Amendment 39-17429 (78 FR 27020, May 9, 2013) (``AD 2012-18-13 R1''). 
Boeing asserted that the ``Related AD'' section could be misinterpreted 
to imply that the inspections required by the proposed AD are in 
addition to the requirements of paragraph (o) of AD 2012-18-13 R1.
    We agree with the commenter's rationale, but the ``Related AD'' 
section is not included in this final rule. Therefore, no change has 
been made.

Request To Address the Termination of AD 2012-18-13 R1

    Boeing requested a clarification that actions required by the 
proposed AD terminate the requirements of paragraph (o) of AD 2012-18-
13 R1. Boeing asserted that the actions of Boeing Alert Service 
Bulletin 737-53A1355, dated March 10, 2017, supersede the actions of 
Boeing Alert Service Bulletin 737-53A1214, Revision 4, dated December 
16, 2011, which are mandated by paragraph (o) of AD 2012-18-13 R1.
    All Nippon Airways (ANA) also requested clarification regarding 
termination of the requirements of paragraph (o) of AD 2012-18-13 R1. 
ANA stated that, because the compliance time is changed to ``after the 
effective date of this AD'' in the proposed AD, the inspections and 
corrective actions required by paragraph (o) of AD 2012-18-13 R1 may be 
terminated as long as the inspections for Zone 1, as specified in 
Boeing Alert Service Bulletin 737-53A1355, dated March 10, 2017, have 
been done within the changed compliance time.
    We agree with the requests for clarification. We have added the 
requested terminating action information as paragraph (i) of this AD 
and redesignated subsequent paragraphs.

Request To Clarify the Zone 2 Definition

    Boeing requested a clarification of the definition of Zone 2 in the 
``Related Service Information under 1 CFR part 51'' paragraph of the 
NPRM. Boeing observed that the definition given could be misleading 
because it does not specify that Zone 2 contains only the gore web lap 
splices outside the apex area.
    We agree and have added the phrase ``outside the apex area'' to the 
specified paragraph of this final rule.

Clarification of Compliance Exception

    We have revised the compliance exception in paragraph (j)(1) of 
this AD to clarify that where Boeing Alert Service Bulletin 737-
53A1355, dated March 10, 2017, uses the phrase ``the original issue 
date of this service bulletin,'' this AD requires using ``the effective 
date of this AD.''

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this final rule 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 burden on any operator or increase the scope of this final 
rule.

[[Page 8327]]

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-53A1355, dated March 
10, 2017. The service information describes procedures for repetitive 
inspections of the gore web in Zone 1 (i.e., inspections around 
fastener locations in the gore web lap splices and around fastener 
locations in the apex area outside the gore web lap splices) and gore 
web lap splices in Zone 2 (i.e., inspections around fastener locations 
in the gore web lap splices outside the apex area) of the aft pressure 
bulkhead, and applicable on-condition actions. The service information 
also describes, for airplanes with an existing single gore web repair, 
procedures for repetitive inspections of the gore web (i.e., 
inspections around fastener locations in the gore web lap splices) and 
repair webs (i.e., inspections around fastener locations in the gore 
web lap splices and around fastener locations in the apex area outside 
the gore web lap splices); and, for airplanes with an existing all gore 
web repair, procedures for repetitive inspections of the repair webs 
(i.e., inspections around fastener locations in the repair gore web lap 
splices and around fastener locations in the apex area outside the 
repair gore web lap splices); and procedures for applicable on-
condition actions. 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 281 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.................  46 work-hours x $85                $0  $3,910 per inspection  $1,098,710 per
                              per hour = $3,910                      cycle.                 inspection cycle.
                              per inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary on-condition 
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 on-condition actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                   Action                                 Labor cost                Parts cost        product
----------------------------------------------------------------------------------------------------------------
Inspection of previous single gore web       8 work-hours x $85 per hour = $680.              $0            $680
 repair.
Inspection of previous all gore web repair.  10 work-hours x $85 per hour = $850               0             850
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the repairs specified in this AD.

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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to transport category airplanes to 
the Director of the System Oversight Division.

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):

2018-04-08 The Boeing Company: Amendment 39-19203; Docket No. FAA-
2017-0766; Product Identifier 2017-NM-046-AD.

(a) Effective Date

    This AD is effective April 3, 2018.

[[Page 8328]]

(b) Affected ADs

    This AD affects AD 2012-18-13 R1, Amendment 39-17429 (78 FR 
27020, May 9, 2013) (``AD 2012-18-13 R1'').

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, certificated in 
any category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/EBD1CEC7B301293E86257CB30045557A?OpenDocument&Highlight=st01219se) 
does not affect the ability to accomplish the actions required by 
this AD. Therefore, for airplanes on which STC ST01219SE is 
installed, a ``change in product'' alternative method of compliance 
(AMOC) approval request is not necessary to comply with the 
requirements of 14 CFR 39.17.

(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 gore web lap splices of the aft 
pressure bulkhead are subject to widespread fatigue damage (WFD). We 
are issuing this AD to detect and correct cracking in the gore webs, 
gore web lap splices, and repair webs of the aft pressure bulkhead, 
which could result in possible rapid decompression and loss of 
structural integrity.

(f) Compliance

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

(g) Required Actions for Group 1 Airplanes

    For airplanes identified as Group 1 in Boeing Alert Service 
Bulletin 737-53A1355, dated March 10, 2017: Within 120 days after 
the effective date of this AD, inspect the airplane, using a method 
approved in accordance with the procedures specified in paragraph 
(k) of this AD.

(h) Actions Required for Compliance

    Except as required by paragraph (j) of this AD: For airplanes 
identified as Group 2 in Boeing Alert Service Bulletin 737-53A1355, 
dated March 10, 2017, at the applicable times specified in paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-53A1355, 
dated March 10, 2017, do all applicable actions identified as 
required for compliance (``RC'') in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1355, dated March 10, 2017.

(i) Termination of Requirements of Paragraph (o) of AD 2012-18-13 R1

    Accomplishment of the initial inspection for Zone 1, defined in 
Boeing Alert Service Bulletin 737-53A1355, dated March 10, 2017, and 
required by paragraph (h) of this AD terminates the requirements of 
paragraph (o) of AD 2012-18-13 R1.

 (j) Exceptions to Service Information Specifications

    (1) For purposes of determining compliance with the requirements 
of this AD: Where Boeing Alert Service Bulletin 737-53A1355, dated 
March 10, 2017, uses the phrase ``the original issue date of this 
service bulletin,'' this AD requires using ``the effective date of 
this AD.''
    (2) Although Boeing Alert Service Bulletin 737-53A1355, dated 
March 10, 2017, specifies to contact Boeing for repair instructions, 
and specifies that action as ``RC'' (Required for Compliance), this 
AD requires repair before further flight using a method approved in 
accordance with the procedures specified in paragraph (k) of this 
AD.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, 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 certification office, 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, Los Angeles ACO Branch, 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 (j)(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) 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 substep is labeled ``RC Exempt,'' then the 
RC requirement is removed from that step or substep. 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 George Garrido, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5232; fax: 562-627-5210; 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 737-53A1355, dated March 10, 
2017.
    (ii) Reserved.
    (3) 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.
    (4) You may view this service information at the FAA, Transport 
Standards Branch, 2200 South 216th St., Des Moines, WA. For 
information on the availability of this material at the FAA, call 
206-231-3195.
    (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 14, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-03600 Filed 2-26-18; 8:45 am]
BILLING CODE 4910-13-P