83 FR 16243 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 83, Issue 73 (April 16, 2018)

We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposed AD was prompted by a report indicating that during a fleet survey on a retired Model 737 airplane, cracking was found common to the windshield and aft sill web. This proposed AD would require, at certain locations, repetitive high frequency eddy current (HFEC) inspections of the windshield and aft sill web, and applicable on-condition actions. We are proposing this AD to address the unsafe condition on these products.

[Federal Register Volume 83, Number 73 (Monday, April 16, 2018)]
[Proposed Rules]
[Pages 16243-16245]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-07648]


========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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


Federal Register / Vol. 83, No. 73 / Monday, April 16, 2018 / 
Proposed Rules

[[Page 16243]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0272; Product Identifier 2018-NM-005-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and 
-500 series airplanes. This proposed AD was prompted by a report 
indicating that during a fleet survey on a retired Model 737 airplane, 
cracking was found common to the windshield and aft sill web. This 
proposed AD would require, at certain locations, repetitive high 
frequency eddy current (HFEC) inspections of the windshield and aft 
sill web, 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 May 31, 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, 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-2018-0272.

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-
0272; 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 NPRM, the regulatory evaluation, any comments received, and other 
information. The street address for Docket Operations (phone: 800-647-
5527) is in the ADDRESSES section. Comments will be available in the AD 
docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: David Truong, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5224; 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-2018-0272; 
Product Identifier 2018-NM-005-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 a report indicating that during a fleet survey on 
a retired Model 737 airplane, cracking was found common to the 
windshield and aft sill web. The airplane had 67,695 flight cycles and 
80,269 flight hours. Two cracks each measured approximately 0.35 inch 
long. The cracks initiated from the edge of the fastener hole and 
propagated toward the outboard edge of the aft sill web. Aft sill web 
cracking is the result of fatigue caused by cyclic pressurization of 
the fuselage and a knife edge condition at the fastener holes. At the 
Boeing metallurgical lab, three additional fastener hole cracks were 
detected common to the aft sill web using an HFEC inspection. The 
cracks also propagated toward the outboard edge of the aft sill web. 
Such cracking could adversely affect the structural integrity of the 
windshield assembly.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Requirements Bulletin 737-53A1377 RB, 
dated December 11, 2017. The service information describes procedures 
for repetitive HFEC inspections of the number 3 windshield and of the 
aft sill web at station 254.6, between S-9 and S-11 on the left- and 
right-hand sides, 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 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 in Boeing Alert Requirements Bulletin 737-53A1377 RB, dated 
December 11, 2017, described previously, except for any differences

[[Page 16244]]

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-2018-0272.

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).

Costs of Compliance

    We estimate that this proposed AD affects 63 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

                                      Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
HFEC inspection..................  4 work-hours x $85               $0  $340 per inspection  $21,420 per
                                    per hour = $340                      cycle.               inspection cycle.
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
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 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 and associated appliances 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-2018-0272; Product Identifier 
2018-NM-005-AD.

(a) Comments Due Date

    We must receive comments by May 31, 2018.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any 
category, as identified in Boeing Alert Requirements Bulletin 737-
53A1377 RB, dated December 11, 2017.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report indicating that during a fleet 
survey on a retired 737 airplane, cracking was found common to the 
windshield and aft sill web. We are issuing this AD to address such 
cracking at these locations, which could adversely affect the 
structural integrity of the windshield assembly.

(f) Compliance

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

(g) Actions for Group 1 Airplanes

    For airplanes identified as Group 1 in Boeing Alert Requirements 
Bulletin 737-53A1377 RB, dated December 11, 2017: Within 120 days 
after the effective date of this AD, do an inspection to correct the 
unsafe condition, using a method approved in accordance with the 
procedures specified in paragraph (j) of this AD.

[[Page 16245]]

(h) Required Actions for Group 2 Airplanes

    For airplanes identified as Group 2 in Boeing Alert Requirements 
Bulletin 737-53A1377 RB, dated December 11, 2017: Except as required 
by paragraph (i) of this AD, at the applicable times specified in 
the ``Compliance'' paragraph of Boeing Alert Requirements Bulletin 
737-53A1377 RB, dated December 11, 2017, do all applicable actions 
identified in, and in accordance with, the Accomplishment 
Instructions of Boeing Alert Requirements Bulletin 737-53A1377 RB, 
dated December 11, 2017.

    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 737-53A1377, dated December 11, 2017, which is referred to 
in Boeing Alert Requirements Bulletin 737-53A1377 RB, dated December 
11, 2017.

(i) Exceptions to Service Information Specifications

    (1) For purposes of determining compliance with the requirements 
of this AD: Where Boeing Alert Requirements Bulletin 737-53A1377 RB, 
dated December 11, 2017, uses the phrase ``the original issue date 
of Requirements Bulletin 737-53A1377 RB,'' this AD requires using 
``the effective date of this AD.''
    (2) Where Boeing Alert Requirements Bulletin 737-53A1377 RB, 
dated December 11, 2017, specifies contacting Boeing, this AD 
requires repair using a method approved in accordance with the 
procedures specified in paragraph (j) of this AD.

(j) 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 (k)(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.

(k) Related Information

    (1) For more information about this AD, contact David Truong, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5224; 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, 2200 South 216th 
St., Des Moines, WA. For information on the availability of this 
material at the FAA, call 206-231-3195.

    Issued in Des Moines, Washington, on March 30, 2018.
Chris Spangenberg,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-07648 Filed 4-13-18; 8:45 am]
BILLING CODE 4910-13-P