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[Federal Register Volume 81, Number 89 (Monday, May 9, 2016)]
[Rules and Regulations]
[Pages 27989-27992]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-10524]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-0246; Directorate Identifier 2014-NM-187-AD; 
Amendment 39-18511; AD 2016-09-13]
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 737-300, -400, and -500 series airplanes. This 
AD was prompted by reports of fatigue cracking found at the left-side 
and right-side upper frames, at a certain area. This AD requires 
repetitive medium frequency eddy current (MFEC) inspections for 
cracking of the left-side and right-side upper frames, and repair 
(including open hole high frequency eddy current (HFEC) inspections for 
cracking of fastener holes) if necessary. This AD also provides an 
optional preventive modification, which terminates the repetitive 
inspections at the modified location. We are issuing this AD to detect 
and correct fatigue cracking of the upper frame, which can grow in size 
and result in a severed frame, leading to rapid decompression and 
consequent reduced structural integrity of the airplane.

DATES: This AD is effective June 13, 2016.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 13, 
2016.

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-2015-
0264.

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-
0246; 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: Galib Abumeri, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office (ACO), 3960 Paramount Boulevard, Lakewood, California 90712-
4137; phone: 562-627-5324; fax: 562-627-5210; email: 
galib.abumeri@faa.gov.

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 737-300, -400, and -500 series airplanes. The NPRM published in 
the Federal Register on February 24, 2015 (80 FR 9667) (``the NPRM''). 
The NPRM was prompted by reports of fatigue cracking found at the left-
side and right-side upper frame, at a certain area. The NPRM proposed 
to require repetitive MFEC inspections for cracking of the left-side 
and right-side upper frames, and repair (including open hole HFEC 
inspections for cracking of fastener holes) if necessary. The NPRM also 
provided an optional preventative modification that would terminate the 
repetitive inspections at the modified location. We are issuing this AD 
to detect and correct fatigue cracking of the upper frame, which can 
grow in size and result in a severed frame, leading to rapid 
decompression and consequent reduced structural integrity of the 
airplane.

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.

Requests To Clarify Compliance Time

    Europe Airpost and Boeing requested that we revise the NPRM to 
clarify the ``Condition'' column of table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014, which specifies airplanes with certain flight cycles 
``on the original issue date of this service bulletin.'' The commenters 
questioned whether the corresponding compliance time should be ``on the 
effective date of the AD.''
    For the reasons suggested by both commenters, we agree to add 
paragraph (i)(3) to this AD to state that the corresponding reference 
point is on the effective date of this AD, and we have included 
reference to paragraph (i)(3) in all appropriate paragraphs in this AD.

Request for Clarify Inspection Requirements

    Boeing requested that we revise paragraph (g) of the proposed AD to 
address the inspection requirements in areas of an existing repair to 
eliminate cracking approved by a Boeing Organization Designation 
Authorization (ODA) via FAA Form 8100-9. Boeing explained that this 
condition is addressed in note (c) of table 1 of paragraph 1.E., 
``Compliance,'' of Boeing

[[Page 27990]]

Alert Service Bulletin 737-53A1339, dated August 12, 2014, and that it 
effectively terminates the initial and repetitive inspections required 
by paragraph (g) of the proposed AD for previously installed frame 
repairs approved by the Boeing ODA via FAA Form 8100-9. Boeing 
requested that the proposed AD address the terminating action for this 
repair condition.
    We agree that clarification is necessary. Boeing ODA-approved 
repairs installed prior to the effective date of this AD are acceptable 
to terminate the initial and repetitive inspections in the area under 
the repair. We have revised paragraph (g) of this AD accordingly, and 
added a new paragraph (g)(1) in this AD.

Request To Clarify Required for Compliance (RC) Requirements

    Southwest Airlines requested that we clarify paragraph (l)(4) of 
the proposed AD. Southwest Airlines explained that note 15 in paragraph 
3.A., ``General Information,'' of Boeing Alert Service Bulletin 737-
53A1339, dated August 12, 2014, states that steps in the Work 
Instructions that are identified as RC must be accomplished once the 
actions specified in Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014, becomes mandated by an AD. Southwest Airlines stated 
that note 15 also states that deviations to steps that are not 
identified as RC do not require approval of an Alternative Method of 
Compliance (AMOC). Southwest Airlines stated that paragraph (l)(4) of 
the proposed AD specifies that any service information that is 
identified as RC requires AMOC approval except as required by paragraph 
(i)(1) of the proposed AD. Paragraph (k) of the proposed AD states that 
the post-repair and post-modification inspections are not mandated by 
the AD, so it is unclear whether the proposed AD would require the 
operator to contact Boeing if there are crack findings during the post-
repair and post-modification inspections, and whether or not the 
resulting repairs are subject to the requirements of the AD.
    We agree to provide clarification. Paragraph (k) of this AD states 
that the post-repair and post-modification inspections specified in 
tables 4 and 5 of paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-53A1339, dated August 12, 2014, are not required 
by this AD (tables 4 and 5 correspond to Parts 6 and 7, respectively, 
of the service information.). The RC steps in those parts are also not 
required by this AD. Any cracking found--whether during accomplishment 
of the actions required by an AD or during routine maintenance--is 
required by 14 CFR 43.13(b) to be repaired before further flight. 
However, for clarity, we have revised paragraph (i)(1) of this AD to 
refer only to Part 3 and Part 4 of the Accomplishment Instructions of 
Boeing Alert Service Bulletin 737-53A1339, dated August 12, 2014. In 
addition, we have revised paragraph (l)(4) of this AD to refer to Part 
2, Part 3, and Part 4 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-53A1339, dated August 12, 2014.

Request To Address Repairs for Damage Other Than Cracking

    Southwest Airlines stated that the NPRM does not specifically 
address existing repairs that prevent accomplishment of the inspections 
proposed in paragraph (g) of the proposed AD. Note (c) in table 1 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-
53A1339, dated August 12, 2014, specifies that an ODA-approved repair, 
via FAA Form 8100-9, installed to eliminate previously found cracking, 
eliminates the need for the repetitive inspections at the repaired 
locations. Southwest requested that we revise the NPRM to apply this 
provision to repairs for damage other than cracking. Southwest Airlines 
also requested that we specifically state that any repair approved by 
Boeing via an FAA 8100-9 combined with approval of an AMOC to paragraph 
(h) of the proposed AD terminates both the initial and repetitive 
inspections required by paragraph (g) of the proposed AD.
    We agree to add clarification regarding initial and repetitive 
inspections. To provide additional clarification in the rule we have 
revised the wording in paragraphs (g) and (h) of this AD. Also, we 
agree to revise the NPRM to include in this final rule, the provision 
for repairs for cracking in paragraph (g)(1) of this AD, and the 
provision for repairs that were installed for damage other than 
cracking that have been re-evaluated and approved by the Boeing ODA 
with an FAA Form 8100-9 combined with an AMOC statement, in paragraph 
(g)(2) of this AD.

Effect of Winglets on the Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that accomplishing Supplemental 
Type Certificate (STC) ST01219SE (http://rgl.faa.gov/
Regulatory_and_Guidance_Library/rgstc.nsf/0/
ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) 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) in this AD, and have added new 
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 
final rule. Therefore, for airplanes on which STC ST01219SE is 
installed, a ``change in product'' AMOC approval request is not 
necessary to comply with the requirements of 14 CFR 39.17.

Change to Paragraph (k) of This AD

    We have revised paragraph (k) of this AD to clarify that the post-
modification inspections are airworthiness limitations that are 
required by maintenance and operational rules; therefore, these 
inspections are not required by this AD.

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

Related Service Information Under 1 CFR Part 51

    Boeing has issued Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014. The service information describes procedures for 
repetitive MFEC inspections for cracking, repair the cracking including 
doing an open hole HFEC inspections for cracking of the holes, and an 
optional modification of an inspection area including open hole and 
surface HFEC inspections for cracking of the area to be modified. 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 109 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

[[Page 27991]]

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspections....................  14 work-hours x $85 per              $0  $1,190 per          $129,710 per
                                  hour = $1,190 per                        inspection cycle.   inspection cycle.
                                  inspection cycle.
Preventive modification          15 work-hours x $85 per               0  $1,275............  $138,975.
 (optional).                      hour = $1,275.
----------------------------------------------------------------------------------------------------------------

    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 actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                 Action                                Labor cost                  Parts cost        product
----------------------------------------------------------------------------------------------------------------
Repair and open hole HFEC inspection....  36 work-hours x $85 per hour =                    $0           $3,060
                                           $3,060.
----------------------------------------------------------------------------------------------------------------

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):

2016-09-13 The Boeing Company: Amendment 39-18511; Docket No. FAA-
2015-0246; Directorate Identifier 2014-NM-187-AD.

(a) Effective Date

    This AD is effective June 13, 2016.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to The Boeing Company Model 737-300, -400, 
and -500 series airplanes, certificated in any category, as 
identified in Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/
rgstc.nsf/0/ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) 
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 reports of fatigue cracking found at the 
left-side and right-side upper frames, at station 360 between 
stringer 13 and stringer 14. We are issuing this AD to detect and 
correct fatigue cracking of the upper frame, which can grow in size 
and result in a severed frame, leading to rapid decompression and 
consequent reduced structural integrity of the airplane.

(f) Compliance

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

(g) Repetitive Inspections for Cracking

    Except as required by paragraphs (i)(2) and (i)(3) of this AD: 
At the applicable times specified in table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014, do a medium frequency eddy current (MFEC) 
inspection for cracking on the left-side and right-side of the upper 
frame at station 360 between stringer 13 and stringer 14, in 
accordance with Part 2 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-53A1339, dated August 12, 2014. If no 
cracking is found, repeat the inspections at the applicable times 
specified in table 1 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-53A1339, dated August 12, 2014. 
Accomplishment of the actions specified in paragraph (j) of this AD 
terminates the repetitive inspections required by this paragraph at 
the modified area only. The initial and repetitive inspections 
required by this paragraph may be terminated in the area under 
repairs installed prior to the effective date of this AD, provided 
they meet the requirements of paragraph (g)(1) or (g)(2) of this AD.
    (1) Repairs were installed to eliminate previously found 
cracking and were

[[Page 27992]]

approved by the Boeing Organization Designation Authorization (ODA) 
with an FAA Form 8100-9.
    (2) Repairs were installed for damage other than cracking that 
have been re-evaluated and approved by the Boeing ODA with an FAA 
Form 8100-9 that includes an alternative method of compliance (AMOC) 
statement to paragraph (h) of this AD.

(h) Repair

    If any cracking is found during any inspection required by 
paragraph (g) of this AD: Before further flight, repair the cracking 
including doing an open hole high frequency eddy current (HFEC) 
inspection for cracking of the holes, in accordance with Part 3 of 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
737-53A1339, dated August 12, 2014, except as required by paragraph 
(i)(1) of this AD. Repair of any crack terminates the initial and 
repetitive inspection requirements of paragraph (g) of this AD for 
the repaired area only. If any cracking is found during any 
inspection required by this paragraph, before further flight, repair 
using a method approved in accordance with the procedures specified 
in paragraph (l) of this AD.

(i) Exceptions to Service Information Specifications

    (1) Where Part 3 and Part 4 of the Accomplishment Instructions 
of Boeing Alert Service Bulletin 737-53A1339, dated August 12, 2014, 
specifies contacting Boeing for repair instructions: Before further 
flight, repair using a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.
    (2) Where Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014, specifies a compliance time ``after the original 
issue date of this service bulletin,'' this AD requires compliance 
within the specified time after the effective date of this AD.
    (3) Where the Condition column of table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1339, dated 
August 12, 2014, specifies a reference point ``on the original issue 
date of this service bulletin,'' for this AD the corresponding 
reference point is on the effective date of this AD.

(j) Optional Preventive Modification

    Modification of an inspection area specified in paragraph (g) of 
this AD, including open hole and surface HFEC inspections for 
cracking of the area to be modified, in accordance with Part 4 of 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
737-53A1339, dated August 12, 2014, except as required by paragraph 
(i)(1) of this AD, terminates the repetitive inspections required by 
paragraph (g) of this AD at the modified location only.

(k) Post-Repair and Post-Modification Inspections

    Tables 4 and 5 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-53A1339, dated August 12, 2014, specify 
post-modification airworthiness limitation inspections in compliance 
to 14 CFR 25.571(a)(3) at the modified locations, which support 
compliance with 14 CFR 121.1109(c)(2) or 129.109(b)(2). As 
airworthiness limitations, these inspections are required by 
maintenance and operational rules. It is therefore unnecessary to 
mandate them in this AD. Deviations from these inspections require 
FAA approval, but do not require an alternative method of 
compliance.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles 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 (m) of this AD. 
Information may be emailed to: 9-ANM-LAACO-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 required by this AD if it is approved by Boeing 
Commercial Airplanes ODA that has been authorized by the Manager, 
Los Angeles 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 (i)(1) of this AD: Where 
Part 2, Part 3, and Part 4 of the Accomplishment Instructions of 
Boeing Alert Service Bulletin 737-53A1339, dated August 12, 2014, 
contains steps that are labeled as RC, the provisions of paragraphs 
(l)(4)(i) and (l)(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. 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.

(m) Related Information

    For more information about this AD, contact Galib Abumeri, 
Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles 
Aircraft Certification Office (ACO), 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; phone: 562-627-5324; fax: 562-627-
5210; email: galib.abumeri@faa.gov.

(n) 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 737-53A1339, dated August 12, 
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 April 28, 2016.
Dionne Palermo,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-10524 Filed 5-6-16; 8:45 am]
 BILLING CODE 4910-13-P
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