Document ID: FAA-2021-0788-0010
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: The Boeing Company Airplanes
Posted Date: 2022-06-29T04:00Z

[Federal Register Volume 87, Number 124 (Wednesday, June 29, 2022)]
[Rules and Regulations]
[Pages 38651-38653]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-13750]

[[Page 38651]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0788; Project Identifier AD-2021-00489-T; 
Amendment 39-22063; AD 2022-11-13]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain The Boeing Company Model 737-700, -800, and -900ER series 
airplanes. This AD was prompted by reports of incorrectly installed 
fuselage skin fasteners. This AD requires a detailed inspection of a 
certain body station bulkhead, between certain stringers, for any 
incorrectly installed fastener common to fuselage skin, and applicable 
on-condition actions. The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective August 3, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of August 3, 
2022.

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 
90740-5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this service information at the 
FAA, Airworthiness Products Section, Operational Safety 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 at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2021-0788.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0788; 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, any 
comments received, and other information. The address for Docket 
Operations is 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: Bill Ashforth, Aerospace Engineer, 
Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3520; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to certain The Boeing 
Company Model 737-700, -800, and -900ER series airplanes. The NPRM 
published in the Federal Register on October 13, 2021 (86 FR 56840). 
The NPRM was prompted by reports of incorrectly installed fuselage skin 
fasteners found at the station (STA) 727 bulkhead. This condition was 
the result of incorrect procedures used to install affected fasteners 
during airplane production that occurred within a certain time period. 
In the NPRM, the FAA proposed to require a detailed inspection of STA 
727 body station bulkhead, between stringers S-22 and S-27, for any 
incorrectly installed fastener common to fuselage skin, and applicable 
on-condition actions. The FAA is issuing this AD to prevent continuous 
operation of the airplane with undetected incorrectly installed 
fasteners, which may generate fatigue cracking that could adversely 
affect the structural integrity of the airplane.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from Boeing, United Airlines, Air Line 
Pilots Association, International, and an individual commenter, who 
supported the NPRM without change.
    The FAA received additional comments from two commenters, including 
Aviation Partners Boeing and Delta Air Lines (DAL). The following 
presents the comments received on the NPRM and the FAA's response.

Effects of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing and DAL commented regarding the 
installation of blended or split scimitar winglets per Supplemental 
Type Certificate (STC) ST00830SE and the effect of that installation on 
compliance with the proposed actions. DAL further requested a change to 
paragraph (c) of the proposed AD to clarify that the installation of 
STC ST00830SE does not affect the accomplishment of the manufacturer's 
service instructions.
    The FAA agrees to clarify that the installation of winglets per STC 
ST00830SE does not affect the accomplishment of the manufacturer's 
service instructions. Therefore, the installation of STC ST00830SE does 
not affect the ability to accomplish the actions required by this AD. 
Operators of airplanes with these winglets do not need to request a 
``change in product'' alternative method of compliance (AMOC) approval 
as specified in 14 CFR 39.17. The FAA has redesignated paragraph (c) of 
the proposed AD as paragraph (c)(1) of this AD, and added paragraph 
(c)(2) to this AD accordingly.

Conclusion

    The FAA reviewed the relevant data, considered any comments 
received, and determined that air safety requires adopting this AD as 
proposed. Except for minor editorial changes, and any other changes 
described previously, this AD is adopted as proposed in the NPRM. None 
of the changes will increase the economic burden on any operator.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 737-53A1384 RB, 
dated September 10, 2020. This service information specifies procedures 
for a detailed inspection for incorrectly installed fasteners at the 
STA 727 bulkhead outer chord common to the fuselage skin between 
stringers S-22 and S-27 on the left and right sides, and applicable on-
condition actions. In addition to repair and replacement, on-condition 
actions include repetitive inspections for cracking of the fuselage 
skin between stringers S-22 and S-27; an open hole high frequency eddy 
current (HFEC) inspection for cracking at all incorrectly installed 
fastener locations; and external and internal general visual 
inspections for repairs of the STA 727 bulkhead. On-condition actions 
also include repetitive HFEC and low frequency eddy current (LFEC) 
inspections in unrepaired areas for cracking of the inner skin from the 
wheel well; of the outer, upper, and lower chords from the wheel well; 
and of the fail-safe chord from the cargo compartment.
    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 ADDRESSES.

[[Page 38652]]

Costs of Compliance

    The FAA estimates that this AD affects 78 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                 Action                          Labor cost           Parts cost      product        operators
----------------------------------------------------------------------------------------------------------------
Inspections............................  13 work-hours x $85 per              $0          $1,105         $86,190
                                          hour = $1,105.
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    The FAA estimates the following costs to do any necessary actions 
that would be required based on the results of the inspection. The 
agency has no way of determining the number of aircraft that might need 
these on-condition actions.

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                 Action                           Labor cost            Parts cost         Cost per product
----------------------------------------------------------------------------------------------------------------
Open hole HFEC inspections..............  21 work-hours x $85 per                 $0  $1,785 per inspection
                                           hour = $85 per inspection                   cycle.
                                           cycle.
HFEC and LFEC inspections...............  36 work-hours x $85 per                  0  3,060 per inspection
                                           hour = $3,060 per                           cycle.
                                           inspection cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data on which to base the work-
hour estimates for the repair and replacement specified in this AD. The 
cost of any required fasteners, which are operator supplied, would be 
minimal.
    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all of the costs of 
this AD may be covered under warranty, thereby reducing the cost impact 
on affected operators.

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.
    The FAA is 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.

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) Will not affect intrastate aviation in Alaska, and
    (3) 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 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:

2022-11-13 The Boeing Company: Amendment 39-22063; Docket No. FAA-
2021-0788; Project Identifier AD-2021-00489-T.

(a) Effective Date

    This airworthiness directive (AD) is effective August 3, 2022.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to The Boeing Company Model 737-700, -800, 
and -900ER series airplanes, certificated in any category, and 
identified in Boeing Alert Requirements Bulletin 737-53A1384 RB, 
dated September 10, 2020.
    (2) Installation of Supplemental Type Certificate (STC) 
ST00830SE does not affect the ability to accomplish the actions 
required by this AD. Therefore, for airplanes on which STC ST00830SE 
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 incorrectly installed 
fuselage skin fasteners. The FAA is issuing this AD to address 
incorrectly installed fasteners. This condition, if not addressed, 
could result in incorrectly installed fasteners going undetected. 
Continuous operation of the airplane with undetected incorrectly 
installed fasteners may generate fatigue cracking that could 
adversely affect the structural integrity of the airplane.

(f) Compliance

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

[[Page 38653]]

(g) Required Actions

    Except as specified by paragraph (h) of this AD: At the 
applicable times specified in the ``Compliance'' paragraph of Boeing 
Alert Requirements Bulletin 737-53A1384 RB, dated September 10, 
2020, do all applicable actions identified in, and in accordance 
with, the Accomplishment Instructions of Boeing Alert Requirements 
Bulletin 737-53A1384 RB, dated September 10, 2020.
    Note 1 to paragraph (g): Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
737-53A1384, dated September 10, 2020, which is referred to in 
Boeing Alert Requirements Bulletin 737-53A1384 RB, dated September 
10, 2020.

(h) Exceptions to Service Information Specifications

    (1) Where the Compliance Time column and the notes of the tables 
in the ``Compliance'' paragraph of Boeing Alert Requirements 
Bulletin 737-53A1384 RB, dated September 10, 2020, use the phrase 
``the Original Issue date of Requirements Bulletin 737-53A1384 RB,'' 
this AD requires using ``the effective date of this AD.''
    (2) Where Boeing Alert Requirements Bulletin 737-53A1384 RB, 
dated September 10, 2020, specifies contacting Boeing for repair 
instructions or for alternative inspections: This AD requires doing 
the repair, or doing the alternative inspections and applicable on-
condition actions, 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, Seattle 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 responsible Flight Standards 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) 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 responsible Flight Standards 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 Company Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Seattle 
ACO Branch, FAA, 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.

(j) Related Information

    For more information about this AD, contact Bill Ashforth, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3520; 
email: [email protected].

(k) 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 737-53A1384 RB, dated 
September 10, 2020.
    (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, 
Airworthiness Products Section, Operational Safety 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, [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on May 25, 2022.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2022-13750 Filed 6-28-22; 8:45 am]
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