83 FR 23775 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 83, Issue 100 (May 23, 2018)

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This AD requires repetitive high frequency eddy current (HFEC) and detailed inspections, as applicable, for cracking of certain aft vertical stiffeners; repetitive detailed inspections for cracking of time-limited repairs, as applicable; a one-time HFEC inspection for cracking of the keel beam upper chord inboard flanges; a one-time general visual inspection for cracking of a certain angle; and applicable on-condition actions. This AD was prompted by a report of cracks in the left-side and right-side keel beam upper chords and aft vertical stiffeners. We are issuing this AD to address the unsafe condition on these products.

[Federal Register Volume 83, Number 100 (Wednesday, May 23, 2018)]
[Rules and Regulations]
[Pages 23775-23778]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-10920]



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Rules and Regulations
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
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under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 

========================================================================


Federal Register / Vol. 83, No. 100 / Wednesday, May 23, 2018 / Rules 
and Regulations

[[Page 23775]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0446; Product Identifier 2018-NM-069-AD; Amendment 
39-19288; AD 2018-10-12]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

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 requires repetitive high frequency eddy current 
(HFEC) and detailed inspections, as applicable, for cracking of certain 
aft vertical stiffeners; repetitive detailed inspections for cracking 
of time-limited repairs, as applicable; a one-time HFEC inspection for 
cracking of the keel beam upper chord inboard flanges; a one-time 
general visual inspection for cracking of a certain angle; and 
applicable on-condition actions. This AD was prompted by a report of 
cracks in the left-side and right-side keel beam upper chords and aft 
vertical stiffeners. We are issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective June 7, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 7, 
2018.
    We must receive comments on this AD by July 9, 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 final rule, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone 562-797-1717; internet https://www.myboeingfleet.com. You may 
view this referenced 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-2018-0446.

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-2018-
0446; 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 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: 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:

Discussion

    We have received a report indicating that cracks were discovered in 
the left-side and right-side keel beam upper chords and both aft 
vertical stiffeners on an airplane that had accumulated 1,304 flight 
cycles since the aft vertical stiffeners had been inspected in 
accordance with Boeing Service Bulletin 737-57A1269. The Boeing Company 
has done an analysis of the affected structure and found that the 
actual stresses on aft vertical stiffeners at left buttock line (LBL) 
and right buttock line (RBL) 6.15 are more than those used to design 
the structure. The increased stresses cause fatigue cracks in the 
stiffeners. If the aft vertical stiffeners have cracks or are severed, 
the fatigue damage may extend into the adjacent keel beam structure. 
The Boeing Company has determined that the existing inspections in 
Boeing Service Bulletin 737-57A1269, required by AD 2005-20-01, 
Amendment 39-14294 (70 FR 56358, September 27, 2005) (``AD 2005-20-
01''), do not provide sufficient inspection intervals for timely crack 
detection in the aft vertical stiffeners. Cracking of the aft vertical 
stiffeners, if not addressed, could result in the inability of the keel 
beam structure to sustain required flight loads, which could adversely 
affect the structural integrity of the airplane.
    We have determined that both AD 2005-20-01 and this AD must be done 
in order to address the identified unsafe condition. Boeing plans to 
issue a revision to Service Bulletin 737-57A1269 in the near future and 
at that time we may consider superseding AD 2005-20-01.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Requirements Bulletin 737-57A1339 RB, 
dated April 16, 2018. The service information describes procedures for 
repetitive surface HFEC and detailed inspections for cracking of the 
aft vertical stiffeners; repetitive detailed inspections for cracking 
of time-limited repairs; a one-time surface HFEC inspection for 
cracking of the keel beam upper chord inboard flanges and a general 
visual inspection for cracking of the associated angle; 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.

FAA's Determination

    We are issuing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or

[[Page 23776]]

develop in other products of the same type design.

AD Requirements

    This AD requires accomplishing the actions identified as ``RC'' 
(required for compliance) in the Accomplishment Instructions of Boeing 
Alert Requirements Bulletin 737-57A1339 RB, dated April 16, 2018, 
described previously, except for any differences identified as 
exceptions in the regulatory text of this 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-2018-0446.

Explanation of Requirements Bulletin

    The FAA worked in conjunction with industry, under the 
Airworthiness Directives Implementation Aviation Rulemaking Committee 
(AD ARC), to enhance the AD system. One enhancement is a process for 
annotating which steps in the service information are ``required for 
compliance'' (RC) with an AD. Boeing has implemented this RC concept 
into Boeing service bulletins. In an effort to further improve the 
quality of ADs and AD-related Boeing service information, a joint 
process improvement initiative was worked between the FAA and Boeing. 
The initiative resulted in the development of a new process in which 
the service information more clearly identifies the actions needed to 
address the unsafe condition in the ``Accomplishment Instructions.'' 
The new process results in a Boeing Requirements Bulletin, which 
contains only the actions needed to address the unsafe condition (i.e., 
only the RC actions).

Interim Action

    We consider this AD interim action. We are currently considering 
requiring the replacement of the vertical stiffeners on certain 
airplanes, which would constitute terminating action for certain 
inspections required by this AD action. The planned compliance time for 
replacing the vertical stiffeners would allow enough time to provide 
notice and opportunity for prior public comment on the merits of the 
modification.

FAA's Justification and Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies waiving notice and comment prior to adoption of this rule 
because cracks in the keel beam upper chords could result in the 
inability of the keel beam structure to sustain required flight loads, 
which could adversely affect the structural integrity of the airplane. 
Therefore, we find good cause that notice and opportunity for prior 
public comment are impracticable. In addition, for the reason(s) stated 
above, we find that good cause exists for making this amendment 
effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment. However, we invite you to send any written data, views, or 
arguments about this final rule. Send your comments to an address 
listed under the ADDRESSES section. Include the docket number FAA-2018-
0446 and Product Identifier 2018-NM-069-AD at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this final rule. We will 
consider all comments received by the closing date and may amend this 
final rule 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 final rule.

Costs of Compliance

    We estimate that this AD affects 67 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
----------------------------------------------------------------------------------------------------------------
Surface HFEC and detailed      2 work-hours x $85                 $0  $170 per inspection   Up to $11,390 per
 inspections of aft vertical    per hour = $170 per                    cycle.                inspection cycle.
 stiffeners (for                inspection cycle.
 Configuration 1 airplanes).
Detailed inspection of aft     2 work-hours x $85                  0  $170 per inspection   Up to $11,390 per
 vertical stiffeners and time-  per hour = $170.                       cycle.                inspection cycle.
 limited repair (for
 Configuration 2 airplanes).
Surface HFEC inspection of     2 work-hours x $85                  0  $170................  $11,390.
 the keel beam upper chord      per hour = $170.
 inboard flanges and a
 general visual inspection of
 the angle (for all
 airplanes).
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would 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

[[Page 23777]]

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 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):

2018-10-12 The Boeing Company: Amendment 39-19288; Docket No. FAA-
2018-0446; Product Identifier 2018-NM-069-AD.

(a) Effective Date

    This AD is effective June 7, 2018.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any 
category.

(d) Subject

    Air Transport Association (ATA) of America Code 57, Wings; 53, 
Fuselage.

(e) Unsafe Condition

    This AD was prompted by a report of cracks in the left-side and 
right-side keel beam upper chords and aft vertical stiffeners. 
Cracks in the aft vertical stiffeners may lead to the inability of 
the keel beam structure to sustain required flight loads, which 
could adversely affect the structural integrity of the airplane.

(f) Compliance

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

(g) Required Actions for Group 1 Airplanes

    For airplanes identified as Group 1 in Boeing Alert Requirements 
Bulletin 737-57A1339 RB, dated April 16, 2018: 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 (k) of this AD.

(h) Required Actions for Group 2 Airplanes

    Except as required by paragraph (i) of this AD: For airplanes 
identified as Group 2 in Boeing Alert Requirements Bulletin 737-
57A1339 RB, dated April 16, 2018, at the applicable times specified 
in the ``Compliance'' paragraph of Boeing Alert Requirements 
Bulletin 737-57A1339 RB, dated April 16, 2018, do all applicable 
actions identified in, and in accordance with, the Accomplishment 
Instructions of Boeing Alert Requirements Bulletin 737-57A1339 RB, 
dated April 16, 2018.
    Note 1 to paragraph (h) of this AD: Guidance for accomplishing 
the actions required by this AD can be found in Boeing Alert Service 
Bulletin 737-57A1339, dated April 16, 2018, which is referred to in 
Boeing Alert Requirements Bulletin 737-57A1339 RB, dated April 16, 
2018.

(i) Exceptions to Service Information Specifications

    (1) For purposes of determining compliance with the requirements 
of this AD: Where Boeing Alert Requirements Bulletin 737-57A1339 RB, 
dated April 16, 2018, uses the phrase ``the original issue date of 
Requirements Bulletin 737-57A1339 RB,'' this AD requires using the 
effective date of this AD.
    (2) Where Boeing Alert Requirements Bulletin 737-57A1339 RB, 
dated April 16, 2018, specifies contacting Boeing, this AD requires 
repair using a method approved in accordance with the procedures 
specified in paragraph (k) of this AD.

(j) Optional Terminating Action for Repetitive Inspections

    Removal of the time-limited repair and accomplishment of 
additional actions in accordance with the Accomplishment 
Instructions of Boeing Alert Requirements Bulletin 737-57A1339 RB, 
dated April 16, 2018, terminate the repetitive inspections of the 
aft vertical stiffeners and time-limited repair, as specified in the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
737-57A1339 RB, dated April 16, 2018, and required by paragraph (h) 
of this AD.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, FAA, has the authority 
to approve AMOCs for this AD, if requested using the procedures 
found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your 
request to your principal inspector or local Flight Standards 
District Office, as appropriate. If sending information directly to 
the manager of the certification office, send it to the attention of 
the person identified in paragraph (l)(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.

(l) 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 (m)(3) and (m)(4) of this AD.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Requirements Bulletin 737-57A1339 RB, dated 
April 16, 2018.
    (ii) Reserved.
    (3) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone 562-797-1717; internet https://www.myboeingfleet.com.
    (4) You may view this service information at the FAA, Transport 
Standards Branch, 2200 South 216th St., Des Moines, WA. For 
information on the availability of this material at the FAA, call 
206-231-3195.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records

[[Page 23778]]

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 May 11, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-10920 Filed 5-22-18; 8:45 am]
 BILLING CODE 4910-13-P