83 FR 7964 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 83, Issue 37 (February 23, 2018)

We are superseding Airworthiness Directive (AD) 2012-12-05, which applied to all The Boeing Company Model 737-100, -200, -200C, - 300, -400, and -500 series airplanes. AD 2012-12-05 required repetitive inspections for cracking under the stop fittings and intercostal flanges and for cracking of the intercostal web, attachment clips, stringer splice channels, frame, reinforcement angle, shear web, frame outer chord and inner chord; a one-time inspection to detect missing fasteners; repetitive inspections of the cargo barrier net fitting for cracking; repetitive inspections for cracking of the stringer S-15L aft intercostal; and repair or corrective action if necessary. For certain airplanes, this AD adds new repetitive inspections of certain areas of the frame inner chord, and applicable on-condition actions. This AD was prompted by reports of additional cracking in locations not covered by the inspections in AD 2012-12-05. We are issuing this AD to address the unsafe condition on these products.

[Federal Register Volume 83, Number 37 (Friday, February 23, 2018)]
[Rules and Regulations]
[Pages 7964-7968]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-03434]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0774; Product Identifier 2017-NM-036-AD; Amendment 
39-19201; AD 2018-04-06]
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 superseding Airworthiness Directive (AD) 2012-12-05, 
which applied to all The Boeing Company Model 737-100, -200, -200C, -
300, -400, and -500 series airplanes. AD 2012-12-05 required repetitive 
inspections for cracking under the stop fittings and intercostal 
flanges and for cracking of the intercostal web, attachment clips, 
stringer splice channels, frame, reinforcement angle, shear web, frame 
outer chord and inner chord; a one-time inspection to detect missing 
fasteners; repetitive inspections of the cargo barrier net fitting for 
cracking; repetitive inspections for cracking of the stringer S-15L aft 
intercostal; and repair or corrective action if necessary. For certain 
airplanes, this AD adds new repetitive inspections of certain areas of 
the frame inner chord, and applicable on-condition actions. This AD was 
prompted by reports of additional cracking in locations not covered by 
the inspections in AD 2012-12-05. We are issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective March 30, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 30, 
2018.
    The Director of the Federal Register approved the incorporation by 
reference of a certain other publication listed in this AD as of July 
23, 2012 (77 FR 36139, June 18, 2012).
    The Director of the Federal Register approved the incorporation by 
reference of a certain other publication listed in this AD as of 
September 9, 2009 (74 FR 38901, August 5, 2009).

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; 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-
0774.

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-
0774; 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: Galib Abumeri, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5324; fax: 562-627-
5210; email: [email protected].

SUPPLEMENTARY INFORMATION: 

[[Page 7965]]

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2012-12-05, Amendment 39-17084 (77 FR 36139, 
June 18, 2012) (``AD 2012-12-05''). AD 2012-12-05 applied 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 15, 
2017 (82 FR 38637). The NPRM was prompted by reports of additional 
cracking in locations not covered by the inspections in AD 2012-12-05. 
The NPRM proposed to continue to require repetitive inspections for 
cracking under the stop fittings and intercostal flanges and for 
cracking of the intercostal web, attachment clips, stringer splice 
channels, frame, reinforcement angle, shear web, frame outer chord and 
inner chord; a one-time inspection to detect missing fasteners; 
repetitive inspections of the cargo barrier net fitting for cracking; 
repetitive inspections for cracking of the stringer S-15L aft 
intercostal; and repair or corrective action if necessary. For certain 
airplanes, the NPRM also proposed to add new repetitive inspections of 
certain areas of the frame inner chord, and applicable on-condition 
actions. We are issuing this AD to detect and correct fatigue cracking 
of the intercostals on the forward and aft sides of the forward entry 
door cutout, which could result in loss of the forward entry door and 
rapid decompression 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.

Support for the NPRM

    The Boeing Company supported the NPRM.

Effect of Winglets on Accomplishing 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 agree 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 Add AMOC Language

    Southwest Airlines (SWA) asked that a note be added to paragraph 
(s) of the proposed AD to provide provisions for AMOCs previously 
approved for AD 2012-12-05. SWA stated that the language in paragraph 
(s) of the proposed AD does not account for AMOCs previously approved 
for AD 2012-12-05.
    We agree with the commenter's request. We have added paragraphs 
(s)(5) and (s)(6) to this AD to include approval of AMOCs previously 
approved for AD 2012-12-05.

Change to Final Rule

    We have revised paragraph (r) of this AD to provide credit for the 
actions specified in paragraphs (i), (j), and (m) of this AD, if those 
actions were performed before September 9, 2009 (the effective date of 
AD 2009-16-14, Amendment 39-15987 (74 FR 38901, August 5, 2009)), using 
Boeing Special Attention Service Bulletin 737-53-1204, dated June 19, 
2003.

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

    We reviewed Boeing Alert Service Bulletin 737-53A1240, Revision 2, 
dated November 2, 2016. The service information describes procedures 
for, among other actions, repetitive inspections of the fastener holes 
in the station (STA) 351.2 frame inner chord at stringer S-17L, and 
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 411 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
----------------------------------------------------------------------------------------------------------------
Inspections for cracking under     18 work-hours x $85              $0  $1,530 per           $628,830 per
 the stop fittings and              per hour = $1,530                    inspection cycle.    inspection cycle.
 intercostal flanges [retained      per inspection
 actions from AD 2012-12-05] (411   cycle.
 airplanes).
Inspection of areas forward of     2 work-hours x $85                0  $170 per inspection  $69,870 per
 the aft entry door [retained       per hour = $170                      cycle.               inspection cycle.
 actions from AD 2012-12-05] (411   per inspection
 airplanes).                        cycle.
Inspection of areas aft of the     1 work-hour x $85                 0  $85 per inspection   $34,935 per
 forward entry door [retained       per hour = $85 per                   cycle.               inspection cycle.
 actions from AD 2012-12-05] (411   inspection cycle.
 airplanes).
Inspection for missing fasteners   1 work-hour x $85               476  $561...............  $230,571.
 [retained actions from AD 2012-    per hour = $85.
 12-05] (411 airplanes).
Inspection of fastener holes (new  27 work-hours x $85               0  $2,295 per           $367,200 per
 action) (160 airplanes).           per hour = $2,295                    inspection cycle.    inspection cycle.
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary repairs that 
are required based on the results of the inspections. We have no way of 
determining the number of aircraft that might need these repairs:

[[Page 7966]]



                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                   Action                                 Labor cost                Parts cost        product
----------------------------------------------------------------------------------------------------------------
Repair of cracking done in accordance with   24 work-hours x $85 per hour =              $11,856         $13,896
 Boeing Alert Service Bulletin 737-53A1240.   $2,040.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that enables us to provide cost 
estimates for the other on-condition corrective actions 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

    We have determined that 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 removing Airworthiness Directive (AD) 
2012-12-05, Amendment 39-17084 (77 FR 36139, June 18, 2012), and adding 
the following new AD:

2018-04-06 The Boeing Company: Amendment 39-19201; Docket No. FAA-
2017-0774; Product Identifier 2017-NM-036-AD.

(a) Effective Date

    This AD is effective March 30, 2018.

(b) Affected ADs

    This AD replaces AD 2012-12-05, Amendment 39-17084 (77 FR 36139, 
June 18, 2012) (``AD 2012-12-05'').

(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/$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 cracking of the station (STA) 
348.2 frame above the two outboard fasteners attaching the frame 
inner chord and door stop fittings, and in the outboard chord at 
stringer S-16L; missing fasteners in the STA 348.2 frame inner 
chord; and additional cracking in locations not covered by the 
inspections in AD 2012-12-05. We are issuing this AD to detect and 
correct fatigue cracking of the intercostals on the forward and aft 
sides of the forward entry door cutout, which could result in loss 
of the forward entry door and rapid decompression of the airplane.

(f) Compliance

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

(g) Retained Initial Compliance Time for Model 737-100, -200, -200C, -
300, -400, and -500 Series Airplanes, With No Changes

    This paragraph restates the requirements of paragraph (i) of AD 
2012-12-05, with no changes. For all Model 737-100, -200, -200C, -
300, -400, and -500 series airplanes, as identified in Boeing Alert 
Service Bulletin 737-53A1204, Revision 1, dated March 26, 2007: 
Before the accumulation of 15,000 total flight cycles, or within 
4,500 flight cycles after November 1, 2005 (the effective date of AD 
2005-20-03, Amendment 39-14296 (70 FR 56361, September 27, 2005) 
(``AD 2005-20-03'')), whichever occurs later: Do the inspections 
required by paragraphs (i) and (j) of this AD.

(h) Retained Initial Compliance Time for Model 737-200C Series 
Airplanes, With No Changes

    This paragraph restates the requirements of paragraph (j) of AD 
2012-12-05, with no changes. For all Model 737-200C series 
airplanes, as identified in Boeing Alert Service Bulletin 737-
53A1204, Revision 1, dated March 26, 2007: Before the accumulation 
of 15,000 total flight cycles, or within 4,500 flight cycles after 
September 9, 2009 (the effective date of AD 2009-16-14, Amendment 
39-15987 (74 FR 38901, August 5, 2009) (``AD 2009-16-14'')), 
whichever occurs later, do the inspection required by paragraph (k) 
of this AD.

(i) Retained Initial Inspection for Group 1 Configuration Airplanes, 
With No Changes

    This paragraph restates the requirements of paragraph (k) of AD 
2012-12-05, with no changes. For Group 1 airplanes identified in 
Boeing Alert Service Bulletin 737-53A1204, Revision 1, dated March 
26, 2007: Perform a

[[Page 7967]]

detailed inspection for cracking of the intercostal web, attachment 
clips, and stringer splice channels; and a high frequency eddy 
current (HFEC) inspection for cracking of the stringer splice 
channels located forward and aft of the forward entry door; and do 
all applicable corrective actions before further flight; in 
accordance with Parts 1 and 2 of the Work Instructions of Boeing 
Special Attention Service Bulletin 737-53-1204, dated June 19, 2003, 
or Boeing Alert Service Bulletin 737-53A1204, Revision 1, dated 
March 26, 2007; or in accordance with Parts 1, 2, 4, and 5 of the 
Work Instructions of Boeing Alert Service Bulletin 737-53A1204, 
Revision 2, dated June 24, 2010. After September 9, 2009 (the 
effective date of AD 2009-16-14), and until July 23, 2012 (the 
effective date of AD 2012-12-05), Boeing Alert Service Bulletin 737-
53A1204, Revision 1, dated March 26, 2007; or Boeing Alert Service 
Bulletin 737-53A1204, Revision 2, dated June 24, 2010; may be used 
to accomplish the actions required by this paragraph. As of July 23, 
2012, only Boeing Alert Service Bulletin 737-53A1204, Revision 2, 
dated June 24, 2010, may be used to accomplish the actions required 
by this paragraph.

(j) Retained Initial Inspection for Cargo Configuration Airplanes 
(Forward of the Forward Entry Door), With No Changes

    This paragraph restates the requirements of paragraph (l) of AD 
2012-12-05, with no changes. For Group 2 cargo airplanes identified 
in Boeing Alert Service Bulletin 737-53A1204, Revision 1, dated 
March 26, 2007: Perform a detailed inspection for cracking of the 
intercostal webs and attachment clips located forward of the forward 
entry door, and do all applicable corrective actions before further 
flight, in accordance with Part 3 of the Work Instructions of Boeing 
Special Attention Service Bulletin 737-53-1204, dated June 19, 2003, 
or Boeing Alert Service Bulletin 737-53A1204, Revision 1, dated 
March 26, 2007; or in accordance with Part 3 of Boeing Alert Service 
Bulletin 737-53A1204, Revision 2, dated June 24, 2010. After 
September 9, 2009 (the effective date of AD 2009-16-14), and until 
July 23, 2012 (the effective date of AD 2012-12-05), Boeing Alert 
Service Bulletin 737-53A1204, Revision 1, dated March 26, 2007; or 
Boeing Alert Service Bulletin 737-53A1204, Revision 2, dated June 
24, 2010; may be used to accomplish the actions required by this 
paragraph. As of July 23, 2012, only Boeing Alert Service Bulletin 
737-53A1204, Revision 2, dated June 24, 2010, may be used to 
accomplish the actions required by this paragraph.

(k) Retained Initial Inspection for Cargo Configuration Airplanes (Aft 
of the Forward Entry Door), With No Changes

    This paragraph restates the requirements of paragraph (m) of AD 
2012-12-05, with no changes. For Group 2 cargo airplanes identified 
in Boeing Alert Service Bulletin 737-53A1204, Revision 1, dated 
March 26, 2007: Perform a detailed inspection for cracking of the 
intercostal webs and attachment clips located aft of the forward 
entry door, and do all applicable corrective actions before further 
flight, in accordance with Part 4 of the Work Instructions of Boeing 
Alert Service Bulletin 737-53A1204, Revision 1, dated March 26, 
2007; or in accordance with Part 3 of Boeing Alert Service Bulletin 
737-53A1204, Revision 2, dated June 24, 2010. As of July 23, 2012 
(the effective date of AD 2012-12-05), only Boeing Alert Service 
Bulletin 737-53A1204, Revision 2, dated June 24, 2010, may be used 
to accomplish the actions required by this paragraph.

(l) Retained Repetitive Inspections, With No Changes

    This paragraph restates the requirements of paragraph (n) of AD 
2012-12-05, with no changes. Repeat the inspections required by 
paragraphs (i), (j), and (k) of this AD thereafter at intervals not 
to exceed 6,000 flight cycles after the previous inspection, or 
within 3,000 flight cycles after September 9, 2009, whichever occurs 
later.

(m) Retained Exceptions to Boeing Alert Service Bulletin 737-53-1204, 
With No Changes

    This paragraph restates the requirements of paragraph (o) of AD 
2012-12-05, with no changes. Do the actions required by paragraphs 
(g), (h), (i), (j), (k), and (l) of this AD by accomplishing all the 
applicable actions specified in the Accomplishment Instructions of 
Boeing Special Attention Service Bulletin 737-53-1204, dated June 
19, 2003; Boeing Alert Service Bulletin 737-53A1204, Revision 1, 
dated March 26, 2007; or Boeing Alert Service Bulletin 737-53A1204, 
Revision 2, dated June 24, 2010; except as provided by paragraphs 
(m)(1) and (m)(2) of this AD. After September 9, 2009 (the effective 
date of AD 2009-16-14), and until July 23, 2012 (the effective date 
of AD 2012-12-05), Boeing Alert Service Bulletin 737-53A1204, 
Revision 1, dated March 26, 2007; or Boeing Alert Service Bulletin 
737-53A1204, Revision 2, dated June 24, 2010; may be used to 
accomplish the actions required by this paragraph. As of July 23, 
2012, only Boeing Alert Service Bulletin 737-53A1204, Revision 2, 
dated June 24, 2010, may be used to accomplish the actions required 
by this paragraph.
    (1) Where Boeing Special Attention Service Bulletin 737-53-1204, 
dated June 19, 2003; Boeing Alert Service Bulletin 737-53A1204, 
Revision 1, dated March 26, 2007; or Boeing Alert Service Bulletin 
737-53A1204, Revision 2, dated June 24, 2010; specifies to contact 
Boeing for repair instructions: Before further flight, repair using 
a method approved in accordance with the procedures specified in 
paragraph (s) of this AD.
    (2) Where Boeing Special Attention Service Bulletin 737-53-1204, 
dated June 19, 2003; or Boeing Alert Service Bulletin 737-53A1204, 
Revision 1, dated March 26, 2007; specifies a compliance time 
relative to the date of a service bulletin, this AD requires 
compliance relative to September 9, 2009 (the effective date of AD 
2009-16-14). Where Boeing Special Attention Service Bulletin 737-53-
1204, dated June 19, 2003; or Boeing Alert Service Bulletin 737-
53A1204, Revision 1, dated March 26, 2007; specifies a compliance 
time relative to the date of the initial release of a service 
bulletin, this AD requires compliance relative to November 1, 2005 
(the effective date of AD 2005-20-03).

(n) Retained Exceptions to Boeing Alert Service Bulletin 737-53A1204, 
Revision 2, Dated June 24, 2010, With No Changes

    This paragraph restates exceptions to Boeing Alert Service 
Bulletin 737-53A1204, Revision 2, dated June 24, 2010, specified in 
paragraph (r) of AD 2012-12-05, with no changes.
    (1) The access and restoration instructions identified in the 
Work Instructions of Boeing Alert Service Bulletin 737-53A1204, 
Revision 2, dated June 24, 2010, are not required by this AD. 
Operators may perform those actions in accordance with approved 
maintenance procedures.
    (2) The use of Boeing Drawing 65-88700 is not allowed when 
accomplishing the actions required by this AD in accordance with the 
Work Instructions of Boeing Alert Service Bulletin 737-53A1204, 
Revision 2, dated June 24, 2010.

(o) Retained Initial and Repetitive Inspections of the S-15L Aft 
Intercostal and Cargo Barrier Net Fitting for Model 737-200C Series 
Airplanes, With No Changes

    This paragraph restates the requirements of paragraph (s) of AD 
2012-12-05, with no changes. For Group 2 airplanes identified in 
Boeing Alert Service Bulletin 737-53A1204, Revision 2, dated June 
24, 2010: Before the accumulation of 15,000 total flight cycles, or 
within 4,500 flight cycles after July 23, 2012 (the effective date 
of AD 2012-12-05), whichever occurs later, do initial detailed and 
HFEC inspections for cracking of the S-15L aft intercostal between 
body station (BS) 348.2 and BS 360, and do a detailed inspection of 
the cargo barrier net fitting at the intercostal, in accordance with 
Figure 3 of the Accomplishment Instructions of Boeing Alert Service 
Bulletin 737-53A1204, Revision 2, dated June 24, 2010. If any 
cracking is found, before further flight, repair using a method 
approved in accordance with the procedures specified in paragraph 
(s) of this AD. Repeat the inspections thereafter at intervals not 
to exceed 6,000 flight cycles.

(p) Actions for Boeing Alert Service Bulletin 737-53A1240, Revision 2, 
Dated November 2, 2016, Including New Repetitive Inspections of Certain 
Fastener Holes

    (1) For airplanes identified as Group 1 and Group 3 in Boeing 
Alert Service Bulletin 737-53A1240, Revision 2, dated November 2, 
2016: Except as required by paragraph (q) of this AD, at the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin 737-53A1240, Revision 2, dated 
November 2, 2016, do all applicable actions identified as ``RC'' 
(required for compliance) in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1240, Revision 2, dated November 2, 2016.
    (2) For airplanes identified as Group 2 in Boeing Alert Service 
Bulletin 737-53A1240, Revision 2, dated November 2, 2016: Within 120 
days after the effective date of this AD, do actions to correct the 
unsafe condition using a method approved in accordance with

[[Page 7968]]

the procedures specified in paragraph (s) of this AD.

(q) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Service Bulletin 737-53A1240, Revision 2, 
dated November 2, 2016, uses the phrase ``after the Revision 2 date 
of this service bulletin,'' for purposes of determining compliance 
with the requirements of this AD, the phrase ``after the effective 
date of this AD'' must be used.
    (2) Where Boeing Alert Service Bulletin 737-53A1240, Revision 2, 
dated November 2, 2016, specifies contacting Boeing, and specifies 
that action as RC: This AD requires using a method approved in 
accordance with the procedures specified in paragraph(s) of this AD.

(r) Credit for Previous Actions

    (1) This paragraph provides credit for the actions specified in 
paragraphs (i), (j), and (m) of this AD, if those actions were 
performed before September 9, 2009 (the effective date of AD 2009-
16-14, Amendment 39-15987 (74 FR 38901, August 5, 2009)), using 
Boeing Special Attention Service Bulletin 737-53-1204, dated June 
19, 2003.
    (2) This paragraph provides credit for the actions specified in 
paragraph (p) of this AD, if those actions were performed before the 
effective date of this AD using Boeing Alert Service Bulletin 737-
53A1240, Revision 1, dated June 29, 2010, provided the conditions 
specified in paragraphs (r)(2)(i) and (r)(2)(ii) of this AD are met 
and except as provided by paragraph (r)(2)(iii) of this AD. Boeing 
Alert Service Bulletin 737-53A1240, Revision 1, dated June 29, 2010, 
was incorporated by reference in AD 2012-12-05.
    (i) Note 1 of paragraph 3.A of the Accomplishment Instructions 
of Boeing Alert Service Bulletin 737-53A1240, Revision 1, dated June 
29, 2010, was disregarded when accomplishing the actions.
    (ii) Boeing Drawing 65-88700 was not used when accomplishing the 
actions in accordance with the Work Instructions of Boeing Alert 
Service Bulletin 737-53A1240, Revision 1, dated June 29, 2010.
    (iii) The access and restoration instructions identified in the 
Work Instructions of Boeing Alert Service Bulletin 737-53A1240, 
Revision 1, dated June 29, 2010, are not required. Operators are 
allowed to perform those actions in accordance with approved 
maintenance procedures.

(s) 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 (t)(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, 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 (q)(2) of this AD: For 
service information that contains steps that are labeled as RC, the 
provisions of paragraphs (s)(4)(i) and (s)(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.
    (5) AMOCs approved previously for AD 2012-12-05 are approved as 
AMOCs for the corresponding provisions of paragraphs (g) through (o) 
of this AD.
    (6) AMOCs approved previously for AD 2012-12-05 are approved as 
AMOCs for the corresponding provisions of Boeing Alert Service 
Bulletin 737-53A1240, Revision 2, dated November 2, 2016, that are 
required by paragraph (p)(1) of this AD.

(t) Related Information

    (1) For more information about this AD, contact Galib Abumeri, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5324; fax: 562-627-5210; email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (u)(6) and (u)(7) of this AD.

(u) 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.
    (3) The following service information was approved for IBR on 
March 30, 2018.
    (i) Boeing Alert Service Bulletin 737-53A1240, Revision 2, dated 
November 2, 2016.
    (ii) Reserved.
    (4) The following service information was approved for IBR on 
July 23, 2012 (77 FR 36139, June 18, 2012).
    (i) Boeing Alert Service Bulletin 737-53A1204, Revision 2, dated 
June 24, 2010.
    (ii) Reserved.
    (5) The following service information was approved for IBR on 
September 9, 2009 (74 FR 38901, August 5, 2009).
    (i) Boeing Alert Service Bulletin 737-53A1204, Revision 1, dated 
March 26, 2007.
    (ii) Reserved.
    (6) 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; 
telephone: 562-797-1717; internet: https://www.myboeingfleet.com.
    (7) You may view this service information at 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.
    (8) 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 9, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-03434 Filed 2-22-18; 8:45 am]
 BILLING CODE 4910-13-P