[Federal Register Volume 83, Number 11 (Wednesday, January 17, 2018)]
[Proposed Rules]
[Pages 2375-2378]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-00662]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-1248; Product Identifier 2017-NM-162-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

[[Page 2376]]


ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 
series airplanes. This proposed AD was prompted by reports of cracks 
found in the main landing gear (MLG) beam forward support fitting. This 
proposed AD would require repetitive inspections for cracking of the 
MLG beam forward support fitting, and applicable on-condition actions. 
We are proposing this AD to address the unsafe condition on these 
products.

DATES: We must receive comments on this proposed AD by March 5, 2018.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone 562-797-1717; internet https://www.myboeingfleet.com. You may 
view this referenced service information at the FAA, Transport 
Standards Branch, 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-2017-1248.

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-
1248; 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 NPRM, the regulatory evaluation, any comments received, 
and other information. The street address for the Docket Office (phone: 
800-647-5527) is in the ADDRESSES section. Comments will be available 
in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: 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:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2017-1248; 
Product Identifier 2017-NM-162-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this NPRM. We will consider all 
comments received by the closing date and may amend this NPRM because 
of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We have received reports indicating that a crack was found in the 
MLG beam forward support fitting around the fastener locations common 
to the rear spar web, below the upper chord on the inboard side of the 
wing buttock line (WBL) 157 rib. Cracks were found on airplanes having 
62,706 to 65,827 total flight hours and 50,152 to 53,039 total flight 
cycles. Because cracks in the MLG beam forward support fitting at this 
location are entirely hidden--the forward side of the fitting (inside 
fuel tanks) by sealant, and the aft side by the rear spar web and MLG 
beam--they cannot be detected reliably during normal maintenance and 
therefore require additional inspections. This cracking of the MLG beam 
forward support fitting, if not corrected, could lead to a fuel leak, 
the inability of a principal structural element to carry limit load, or 
an MLG collapse that could prevent continued safe flight and landing.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-57A1334, dated 
September 26, 2017. The service information describes procedures for 
repetitive high frequency eddy current (HFEC) inspections for cracking 
of the MLG beam forward support fitting around the fastener locations 
common to the rear spar web, below the upper chord on the inboard side 
of the WBL 157 rib, and applicable on-condition actions (e.g., repair). 
This service information is reasonably available because the interested 
parties have access to it through their normal course of business or by 
the means identified in the ADDRESSES section.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require accomplishment of the actions 
identified as ``RC'' (required for compliance) in the Accomplishment 
Instructions of Boeing Alert Service Bulletin 737-57A1334, dated 
September 26, 2017, described previously, except for any differences 
identified as exceptions in the regulatory text of this proposed AD.
    For information on the procedures and compliance times, see this 
service information at http://www.regulations.gov by searching for and 
locating Docket No. FAA-2017-1248.

Explanation of Applicability

    Model 737 airplanes having line numbers 1 through 291 have a limit 
of validity (LOV) of 34,000 total flight cycles, and the actions 
proposed in this NPRM, as specified in Boeing Alert Service Bulletin 
737-57A1334, dated September 26, 2017, would be required at a 
compliance time occurring after that LOV. Although operation of an 
airplane beyond its LOV is prohibited by 14 CFR 121.1115 and 129.115, 
this NPRM would include those airplanes in the applicability so that 
these airplanes are tracked in the event the LOV is extended in the 
future.

Costs of Compliance

    We estimate that this proposed AD affects 160 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

[[Page 2377]]



                                                 Estimated Costs
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                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
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HFEC inspections...............  Up to 81 work-hours x                $0  Up to $6,885 per    Up to $1,101,600
                                  $85 per hour = Up to                     inspection cycle.   per inspection
                                  $6,885 per inspection                                        cycle.
                                  cycle.
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    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
AD. Because the number of work-hours can vary widely, depending on the 
inspection findings, these figures were not included in the service 
information.

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 proposed 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 determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national Government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

The Boeing Company: Docket No. FAA-2017-1248; Product Identifier 
2017-NM-162-AD.

(a) Comments Due Date

    We must receive comments by March 5, 2018.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model -100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any 
category.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by the report of a crack indication in the 
main landing gear (MLG) beam forward support fitting on the inboard 
side of the wing buttock line (WBL) 157 rib, and multiple reports of 
similar crack findings on other airplanes. We are issuing this AD to 
detect and correct cracking of the MLG beam forward support fitting 
on the inboard side of the WBL 157 rib. Undetected cracks could lead 
to a fuel leak, the inability of a principal structural element to 
carry limit load, or an MLG collapse that could prevent continued 
safe flight and landing.

(f) Compliance

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

(g) Required Actions

    (1) For Group 1 airplanes identified in Boeing Alert Service 
Bulletin 737-57A1334, dated September 26, 2017: Within 120 days 
after the effective date of this AD, inspect the airplane and do all 
applicable corrective actions using a method approved in accordance 
with the procedures specified in paragraph (i) of this AD.
    (2) For Group 2 airplanes identified in Boeing Alert Service 
Bulletin 737-57A1334, dated September 26, 2017: Except as required 
by paragraph (h) of this AD, at the applicable times specified in 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-57A1334, dated September 26, 2017, do all applicable actions 
identified as ``RC'' (required for compliance) in, and in accordance 
with, the Accomplishment Instructions of Boeing Alert Service 
Bulletin 737-57A1334, dated September 26, 2017.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Service Bulletin 737-57A1334, dated 
September 26, 2017, uses the phrase ``after the original issue 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 737-57A1334, dated 
September 26, 2017, specifies contacting Boeing, and specifies that 
action as RC: This AD requires using a method approved in accordance 
with the procedures specified in paragraph (i) of this AD.

(i) 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 (j)(1) of this AD. Information 
may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector,

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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 (h)(2) of this AD: For 
service information that contains steps that are labeled as RC, the 
provisions of paragraphs (i)(4)(i) and (i)(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.

(j) Related Information

    (1) 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].
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Transport Standards Branch, 1601 Lind Avenue 
SW, Renton, WA. For information on the availability of this material 
at the FAA, call 425-227-1221.

    Issued in Renton, Washington, on January 5, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-00662 Filed 1-16-18; 8:45 am]
 BILLING CODE 4910-13-P


