[Federal Register Volume 86, Number 87 (Friday, May 7, 2021)]
[Proposed Rules]
[Pages 24551-24554]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-09299]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0332; Project Identifier AD-2020-01414-T]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain The Boeing Company Model 787-8 and 787-9 airplanes. This 
proposed AD was prompted by reports that shimming requirements were not 
met during the assembly of certain structural joints, which can result 
in reduced fatigue thresholds of the affected structural joints. This 
proposed AD would require repetitive inspections for cracking of 
certain areas of the front spar pickle fork and front spar outer chord 
and repair of any cracking found. The FAA is proposing this AD to 
address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by June 21, 
2021.

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 https://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, 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 on the internet at

[[Page 24552]]

https://www.regulations.gov by searching for and locating Docket No. 
FAA-2021-0332.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0332; 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, any comments received, and other information. The street 
address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Greg Rutar, Aerospace Engineer, 
Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3529; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-0332; Project Identifier 
AD-2020-01414-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
the proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this proposed AD.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to Greg 
Rutar, Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3529; email: [email protected]. Any commentary that the FAA receives 
which is not specifically designated as CBI will be placed in the 
public docket for this rulemaking.

Background

    The FAA has received reports that shimming requirements were not 
met during the assembly of certain areas of the front spar pickle fork 
and front spar outer chord structural joints, which can result in 
reduced fatigue thresholds of the affected structural joints. The 
existing inspection program does not adequately detect this fatigue 
cracking. The affected locations are common to the front spar pickle 
fork, between stringer S-22 and stringer S-25, and the front spar body 
chord, between stringer S-25 and buttock line (BL) 0', on the left and 
right sides. Not meeting the shimming requirements during assembly of 
the station (STA) 873 front spar pickle fork and front spar body chord 
structure joints results in excessive pull-up forces, fastener 
shanking, excessive burr heights in metallic members, and metallic 
chips (foreign object debris) in fastened interfaces, which all degrade 
fatigue performance of any affected structural joints.
    Undetected fatigue cracking could weaken primary structure so it 
cannot sustain limit load, which could result in reduced structural 
integrity of the airplane.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin B787-81205-
SB530075-00 RB, Issue 001, dated September 8, 2020. The service 
information describes procedures for repetitive high frequency eddy 
current (HFEC) inspections for cracking around all the fasteners common 
to the front spar pickle fork outer chord surface between stringer S-22 
and stringer S-24 at STA 873 on the left and right sides, and along the 
entire forward edge of the front spar pickle fork outer chord covered 
by the body chord splice angle between stringer S-24 and stringer S-25 
at STA 873 on the left and right sides, and repair of any cracking 
found. The service information also describes procedures for repetitive 
ultrasonic (UT) inspections for cracking of the front spar pickle fork 
outer chord along the upper, lower and aft edges of the end fittings at 
stringer S-23 at STA 873, on the left and right sides, and repair of 
any cracking found.
    The FAA also reviewed Boeing Alert Requirements Bulletin B787-
81205-SB530076-00 RB, Issue 001, dated September 8, 2020. The service 
information describes procedures for repetitive HFEC inspections for 
cracking along the entire forward edge of the front spar body chord in 
the area covered by the body chord splice angle at stringer S-25 on the 
left and right sides, and the splice fitting at BL 0', STA 873, and 
repair of any cracking found. The service information also describes 
procedures for repetitive detailed inspections of the front spar body 
chord horizontal flange surface between stringer S-26 to stringer S-40 
at STA 873 on the left and right sides and repair of any cracking 
found. The service information also describes procedures for repetitive 
UT inspections for cracking of the of the front spar body chord 
horizontal flange along the upper and lower edges of the end fittings 
at stringer S-27, at STA 873 on the left and right sides, and repair of 
any cracking found.
    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

    The FAA is proposing this AD because the agency 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 Bulletins B787-81205-SB530075-
00 RB and B787-81205-SB530076-00 RB, both Issue 001, both dated 
September 8, 2020, 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 https://www.regulations.gov by searching for and 
locating Docket No. FAA-2021-0332.

Explanation of Requirements Bulletin

    The FAA worked in conjunction with industry, under the 
Airworthiness

[[Page 24553]]

Directive 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

    The FAA estimates that this proposed AD affects 79 airplanes of 
U.S. registry. The FAA estimates the following costs to comply with 
this proposed AD:

                                      Estimated Costs for Required Actions
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                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Repetitive inspections.........  14 work-hours x $85 per              $0  $1,190 per          $94,010 per
                                  hour = $1,190 per                        inspection cycle.   inspection cycle.
                                  inspection cycle.
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    The FAA has received no definitive data on which to base the cost 
estimates for the on-condition repairs 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.
    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

    The FAA 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) Would not affect intrastate aviation in Alaska, and
    (3) Would 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:

The Boeing Company: Docket No. FAA-2021-0332; Project Identifier AD-
2020-01414-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by June 21, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 787-8 and 787-9 
airplanes, certificated in any category, as identified in Boeing 
Alert Requirements Bulletin B787-81205-SB530075-00 RB, Issue 001, 
dated September 8, 2020.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports that shimming requirements were 
not met during the assembly of certain areas of the front spar 
pickle fork and front spar outer chord structural joints, which can 
result in reduced fatigue thresholds of the affected structural 
joints. The FAA is issuing this AD to address undetected fatigue 
cracking, which could weaken primary structure so it cannot sustain 
limit load, and could result in reduced structural integrity of the 
airplane.

(f) Compliance

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

(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 Bulletins B787-81205-SB530075-00 RB and B787-
81205-SB530076-00 RB, both Issue 001, both dated September 8, 2020, 
do all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletins 
B787-81205-SB530075-00 RB and B787-81205-SB530076-00 RB, both Issue 
001, both dated September 8, 2020.

    Note 1 to paragraph (g):  Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletins 
B787-81205-SB530075-00 and B787-81205-SB530076-00, both Issue 001, 
dated both September 8, 2020, which are referred to in Boeing Alert 
Requirements Bulletins B787-81205-SB530075-00 RB and B787-81205-
SB530076-00 RB, both Issue 001, both dated September 8, 2020.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Requirements Bulletin B787-81205-
SB530076-00 RB, Issue 001, dated September 8, 2020, uses the phrase 
``the issue 001 date of the Requirements Bulletin B787-81205-
SB530076-00 RB,'' this AD requires using ``the effective date of 
this AD.''
    (2) Where Boeing Alert Requirements Bulletins B787-81205-
SB530075-00 RB and B787-81205-SB530076-00 RB, both Issue 001, both 
dated September 8, 2020, specify contacting Boeing for repair 
instructions: This AD requires doing the repair using a method 
approved in accordance with the

[[Page 24554]]

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)(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 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

    (1) For more information about this AD, contact Greg Rutar, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3529; 
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, 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.

    Issued on April 16, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-09299 Filed 5-6-21; 8:45 am]
BILLING CODE 4910-13-P