Document ID: FAA-2016-9523-0012
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: The Boeing Company Airplanes
Posted Date: 2018-05-15T04:00Z

[Federal Register Volume 83, Number 94 (Tuesday, May 15, 2018)]
[Rules and Regulations]
[Pages 22351-22354]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-09864]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9523; Product Identifier 2016-NM-134-AD; Amendment 
39-19270; AD 2018-09-13]
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 all The 
Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series 
airplanes. This AD was prompted by reports indicating additional 
cracking in the inspar upper skin at wing buttock line (WBL) 157 and in 
the skin at two holes common to the rear spar in the same area, and 
rear spar web cracks were also noted on both wings. Subsequent 
inspections revealed that the right rear spar upper chord was almost 
completely severed and the left rear spar upper chord was completely 
severed. Additional reports identified cracking in the main landing 
gear (MLG) beam forward support fitting. This AD requires the 
installation of standard-size fasteners for a certain configuration and 
inspections for any crack in certain locations of the rear spar. We are 
issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective June 19, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of June 19, 
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; 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-2016-9523.

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-
9523; or in person at Docket Operations 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 Docket Operations (phone: 800-647-
5527) is Docket Operations, 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: Payman Soltani, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5313; 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 January 5, 2017 (82 FR 1254). 
The NPRM was prompted by reports of cracking in locations outside the 
inspection area identified in AD 2014-12-13, Amendment 39-17874 (79 FR 
39300, July 10, 2014) (``AD 2014-12-13''), in the inspar upper skin at 
WBL 157 and in the skin at two holes common to the rear spar in the 
same area, and in the rear spar web on both wings. Subsequent 
inspections revealed that the right rear spar upper chord was almost 
completely severed and the left rear spar upper chord was completely 
severed. Operators also reported cracking in the MLG beam forward 
support fitting.
    We subsequently issued a supplemental notice of proposed rulemaking 
(SNPRM) which was published in the Federal Register on August 11, 2017 
(83 FR 37549) (``the first SNPRM''). The first SNPRM proposed to 
require expanding the inspection area, add applicable related 
investigative and corrective actions, and to terminate (rather than 
supersede) the requirements of AD 2014-12-13 after accomplishment of 
the initial inspections.
    We issued a second SNPRM which was published in the Federal 
Register on January 17, 2018 (83 FR 2378) (``the 2018 SNPRM''). The 
2018 SNPRM proposed to require the installation of standard-size 
fasteners for a certain

[[Page 22352]]

configuration. We are issuing this AD to address cracking of the 
forward and aft support fittings for the main landing gear beam, and 
the rear spar upper chord and rear spar web in the area of rear spar 
station 224.14, which could grow and result in a fuel leak and possible 
fire.

Comments

    We gave the public the opportunity to participate in developing 
this final rule. We have considered the comment received. Boeing 
supported the 2018 SNPRM.

Conclusion

    We reviewed the relevant data, considered the comment received, and 
determined that air safety and the public interest require adopting 
this final rule as proposed, except for minor editorial changes. We 
have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
2018 SNPRM for addressing the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the 2018 SNPRM.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-57A1318, Revision 1, 
dated July 22, 2016. This service information describes procedures for 
repetitive high frequency eddy current (HFEC) open hole inspections for 
any cracking in the forward support fitting, the aft support fitting, 
the rear spar upper chord, and the rear spar web at the 12 fastener 
holes (locations 1-12). This service information also describes 
procedures for optional HFEC open hole inspections for any cracking in 
the forward support fitting, the aft support fitting, the rear spar 
upper chord, and the rear spar web, and HFEC surface inspections for 
any cracking in the rear spar upper chord and rear spar upper web, as 
applicable. This service information also describes procedures for 
related investigative and corrective actions.
    We also reviewed Boeing Alert Service Bulletin 737-57A1328, dated 
July 22, 2016. This service information describes procedures for 
repetitive eddy current inspections of the left and right wing for any 
cracking in the inspar upper skin and at the repair parts if 
applicable, and related investigative and corrective 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 471 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
----------------------------------------------------------------------------------------------------------------
HFEC open hole inspections.......  82 work-hours x $85              $0  $6,970 per           $3,282,870 per
                                    per hour = $6,970                    inspection cycle.    inspection cycle.
                                    per inspection
                                    cycle.
Eddy current inspection..........  14 work-hours x $85              $0  $1,190 per           $560,490 per
                                    per hour = $1,190                    inspection cycle.    inspection cycle.
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

                                      Estimated Costs for Optional Actions
----------------------------------------------------------------------------------------------------------------
                 Action                           Labor cost            Parts cost         Cost per product
----------------------------------------------------------------------------------------------------------------
Inspection..............................  Up to 41 work-hours x $85               $0  Up to $1,641,435 per
                                           per hour = $3,485 per                       inspection cycle.
                                           inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that will enable us to provide 
cost estimates for the on-condition 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 and 
associated appliances 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

[[Page 22353]]

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):

2018-09-13 The Boeing Company: Amendment 39-19270; Docket No. FAA-
2016-9523; Product Identifier 2016-NM-134-AD.

(a) Effective Date

    This AD is effective June 19, 2018.

(b) Affected ADs

    This AD affects AD 2014-12-13, Amendment 39-17874 (79 FR 39300, 
July 10, 2014) (``AD 2014-12-13''); and AD 2015-21-08, Amendment 39-
18301 (80 FR 65921, October 28, 2015) (``AD 2015-21-08'').

(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 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 57, Wings.

(e) Unsafe Condition

    This AD was prompted by reports of additional cracking in the 
inspar upper skin at wing buttock line 157 and in the skin at two 
holes common to the rear spar in the same area; rear spar web cracks 
were also noted on both wings. Subsequent inspections revealed that 
the right rear spar upper chord was almost completely severed and 
the left rear spar upper chord was completely severed. Additional 
reports identified cracking in the main landing gear (MLG) beam 
forward support fitting. We are issuing this AD to detect and 
correct cracking of the forward and aft support fittings for the MLG 
beam, and the rear spar upper chord and rear spar web in the area of 
rear spar station 224.14, which could grow and result in a fuel leak 
and possible fire.

(f) Compliance

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

(g) Required Actions for Group 1 Airplanes (MLG Support Fittings and 
Rear Spar)

    For airplanes identified as Group 1 in Boeing Alert Service 
Bulletin 737-57A1318, Revision 1, dated July 22, 2016: At the 
applicable time specified in table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016, do applicable inspections and 
corrective actions using a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.

(h) Required Actions for Groups 2-7 Airplanes (MLG Support Fittings and 
Rear Spar)

    For airplanes identified as Groups 2-7 in Boeing Alert Service 
Bulletin 737-57A1318, Revision 1, dated July 22, 2016: At the 
applicable time specified in table 2 through table 9 of paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016, except as required by paragraph 
(j)(3) of this AD, do high frequency eddy current (HFEC) open hole 
inspections for any cracking in the forward support fitting, the aft 
support fitting, the rear spar upper chord, and the rear spar web at 
the 12 fastener holes (locations 1-12); or HFEC open hole 
inspections for any cracking in the forward support fitting, the aft 
support fitting, the rear spar upper chord, and the rear spar web, 
and an HFEC surface inspection for any cracking in the rear spar 
upper chord and rear spar upper web; as applicable; and do all 
applicable related investigative and corrective actions; in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-57A1318, Revision 1, dated July 22, 2016, 
except as provided by paragraph (h)(1) of this AD, and except as 
required by paragraphs (h)(2) and (j)(1) of this AD. Do all 
applicable related investigative and corrective actions before 
further flight. Thereafter, repeat the HFEC inspection at the 
applicable time specified in table 2 through table 9 of paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016.
    (1) Options provided in Boeing Alert Service Bulletin 737-
57A1318, Revision 1, dated July 22, 2016, for accomplishing the 
inspection are acceptable for the corresponding requirements in the 
introductory text of paragraph (h) of this AD, provided that the 
inspections are done at the applicable times in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016.
    (2) For Group 7, Configuration 1, airplanes identified in Boeing 
Alert Service Bulletin 737-57A1318, Revision 1, dated July 22, 2016: 
Install standard-size fasteners in accordance with figures 29 and 30 
of Boeing Alert Service Bulletin 737-57A1318, Revision 1, dated July 
22, 2016. If the existing fastener holes exceed the permitted hole 
diameter, repair before further flight using a method approved in 
accordance with the procedures specified in paragraph (l) of this 
AD.

(i) Eddy Current Inspection (Inspar Upper Skin)

    For airplanes identified in Boeing Alert Service Bulletin 737-
57A1328, dated July 22, 2016: At the applicable time specified in 
table 1 and table 2 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-57A1328, dated July 22, 2016, except as 
required by paragraph (j)(2) of this AD, do an eddy current 
inspection of the left and right wings for any cracking in the 
inspar upper skin, and at the repair parts if installed, and do all 
applicable related investigative and corrective actions, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-57A1328, dated July 22, 2016, except as 
required by paragraph (j)(1) of this AD. Do all related 
investigative and corrective actions before further flight. 
Thereafter, repeat the eddy current inspection at the applicable 
time specified in table 1 and table 2 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1328, dated 
July 22, 2016.

(j) Exceptions to the Service Information

    (1) If any cracking is found during any inspection required by 
this AD, and Boeing Alert Service Bulletin 737-57A1318, Revision 1, 
dated July 22, 2016; or Boeing Alert Service Bulletin 737-57A1328, 
dated July 22, 2016; specifies to contact Boeing for appropriate 
action: 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 737-57A1328, dated July 
22, 2016, specifies a compliance time ``after the Original Issue 
date of this service bulletin,'' this AD requires compliance within 
the specified compliance time after the effective date of this AD.
    (3) Where Boeing Alert Service Bulletin 737-57A1318, Revision 1, 
dated July 22, 2016, specifies a compliance time ``after the 
Revision 1 date of this service bulletin, whichever occurs later,'' 
this AD requires compliance within the specified compliance time 
after the effective date of this AD.

(k) Terminating Action

    (1) Accomplishing the initial inspections and applicable related 
investigative and corrective actions required by paragraphs (g), 
(h), and (i) of this AD, as applicable, terminates all requirements 
of AD 2015-21-08.
    (2) Accomplishing the initial inspections and applicable related 
investigative and corrective actions required by paragraphs (g) and 
(h) of this AD, as applicable, terminates all requirements of AD 
2014-12-13.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, FAA, has the authority 
to approve AMOCs

[[Page 22354]]

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 (m) 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) AMOCs approved previously for AD 2014-12-13 are approved as 
AMOCs for the corresponding provisions of paragraphs (g) and (h) of 
this AD.
    (5) Except as required by paragraph (j)(1) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (l)(5)(i) and 
(l)(5)(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.

(m) Related Information

    For more information about this AD, contact Payman Soltani, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5313; fax: 562-627-5210; email: [email protected].

(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 737-57A1318, Revision 1, dated 
July 22, 2016.
    (ii) Boeing Alert Service Bulletin 737-57A1328, dated July 22, 
2016.
    (3) For Boeing 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.
    (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 Des Moines, Washington, on April 27, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-09864 Filed 5-14-18; 8:45 am]
 BILLING CODE 4910-13-P