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Published 2020-12-10 · Federal Register document 2020-27006

Airworthiness Directives; The Boeing Company Airplanes

Publication summary

The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. This AD was prompted by a determination that the upper wing skin at engine nacelle points may be subject to undetected cracking. This AD requires repetitive ultrasonic inspections of the upper wing skin at certain engine strut positions for cracking; repetitive detailed and ultrasonic inspections of the strut lower spar fitting, diagonal brace strut end clevis, and diagonal brace wing attach end clevis for cracking; repetitive detailed inspections of lower link fitting at certain engine strut positions for cracking; and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:24:04.586324+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2020-f01fbc4d7ab3dbaa
Source row
results[368]
Raw source SHA-256
f01fbc4d7ab3dbaae6a412acd9ff6cece48db77a6a882e46e8f8087200be3837

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2020-21-16
Effective date printed in this edition
2021-01-14
Read 11 complete recorded clauses
Effective Date
(a) Effective Date

    This AD is effective January 14, 2021.

Exact source excerpt. Text positions 9495–9559, end exclusive, in the original decoded publication. SHA-256: 2168665ef208cf33ad292001a2d3fbdbaabb6ece4a55c9ab30192976ace2b999

Affected ADs
(b) Affected ADs

    None.

Exact source excerpt. Text positions 9559–9588, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0

Applicability wording · Applicability
(c) Applicability

    This AD applies to all The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP series airplanes, certificated 
in any category.

Exact source excerpt. Text positions 9588–9829, end exclusive, in the original decoded publication. SHA-256: 9037d87439fe8bf0759fd548a1fac7fc8e026580892d5bc553e52132832ba560

Subject
(d) Subject

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

Exact source excerpt. Text positions 9829–9906, end exclusive, in the original decoded publication. SHA-256: 52f35cb894eac2144f3b0de7a455ce53cfbcfebe8c2ccd3b1ccbff2308cfe7df

Unsafe Condition
(e) Unsafe Condition

    This AD was prompted by a determination that the upper wing skin 
at engine nacelle attachment points may be subject to undetected 
cracking. The FAA is issuing this AD to address undetected cracking 
in the upper wing skin, strut lower spar fitting, or clevis lugs at 
either end of the diagonal brace and lower link fitting. This 
condition, if not addressed, could adversely affect the structural 
integrity of the engine strut and may lead to the separation of the 
strut to wing box assembly.

Exact source excerpt. Text positions 9906–10431, end exclusive, in the original decoded publication. SHA-256: cd3ba08de4dcce1e033c6f9cb1e11025991d998edac5aa538a2a268aea675e67

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 10431–10533, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Required Actions
(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 747-57A2363 RB, dated December 23, 2019, 
do all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
747-57A2363 RB, dated December 23, 2019.

    Note 1 to paragraph (g):  Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
747-57A2363, dated December 23, 2019, which is referred to in Boeing 
Alert Requirements Bulletin 747-57A2363 RB, dated December 23, 2019.

Exact source excerpt. Text positions 10533–11212, end exclusive, in the original decoded publication. SHA-256: 56e1ffcad1a6901b7b6bffb566aee6dc812976ee72cef86ebeb6b0b5210f097e

Exceptions to Service Information Specifications
(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019, uses the phrase ``the original issue date 
of Requirements Bulletin 747-57A2363

[[Page 79415]]

RB,'' this AD requires using ``the effective date of this AD.''
    (2) Where Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019, specifies contacting Boeing for repair 
instructions: This AD requires doing the repair before further 
flight using a method approved in accordance with the procedures 
specified in paragraph (i) of this AD.

Exact source excerpt. Text positions 11212–11819, end exclusive, in the original decoded publication. SHA-256: 06fafa57e78d9e34e9ec180e48fcb26d7f3b1328675e42d12554af944ff4aeca

Alternative Methods of Compliance (AMOCs)
(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 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, 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 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.

Exact source excerpt. Text positions 11819–13093, end exclusive, in the original decoded publication. SHA-256: 489a97e657e231f9f6b6d7138ae934b984c590acd7d3f4d7f363ff0a72017a54

Related Information
(j) Related Information

    (1) For more information about this AD, contact Eric Lin, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3523; 
email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (k)(3) and (4) of this AD.

Exact source excerpt. Text positions 13093–13517, end exclusive, in the original decoded publication. SHA-256: 90e9ddd1168ef3416ad78b0344e06ab088ca19f095be01976943212165d97160

Material Incorporated by Reference
(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 747-57A2363 RB, dated 
December 23, 2019.
    (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 [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 13517–14802, end exclusive, in the original decoded publication. SHA-256: 591a8bf74af43c50b1e990d49d18ef3dcb55df0fa747ea0e98cee234d9b091ff

No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.

Find all recorded historical references to AD 2020-21-16 · 0 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 32eda888476089a149a4e7c57d8d80bf96b14cb091eade731914daa44d589769. Source manifest: 2dd967df3341ff24f8bc282704ceecac8a8a6a95ca5b8f9ee4a5590c61c1de39.

Official source · 2020-12-10

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[Federal Register Volume 85, Number 238 (Thursday, December 10, 2020)]
[Rules and Regulations]
[Pages 79413-79415]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-27006]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0573; Product Identifier 2020-NM-078-AD; Amendment 
39-21289; AD 2020-21-16]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 
747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 
747SP series airplanes. This AD was prompted by a determination that 
the upper wing skin at engine nacelle points may be subject to 
undetected cracking. This AD requires repetitive ultrasonic inspections 
of the upper wing skin at certain engine strut positions for cracking; 
repetitive detailed and ultrasonic inspections of the strut lower spar 
fitting, diagonal brace strut end clevis, and diagonal brace wing 
attach end clevis for cracking; repetitive detailed inspections of 
lower link fitting at certain engine strut positions for cracking; and 
applicable on-condition actions. The FAA is issuing this AD to address 
the unsafe condition on these products.

DATES: This AD is effective January 14, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of January 14, 
2021.

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 on 
the internet at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2020-0573.

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-2020-
0573; 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: Eric Lin, Aerospace Engineer, Airframe 
Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 
98198; phone and fax: 206-231-3523; email: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to all The Boeing Company 
Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 
747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series 
airplanes. The NPRM published in the Federal Register on June 30, 2020 
(85 FR 39108). The NPRM was prompted by a determination that the upper 
wing skin at engine nacelle points may be subject to undetected 
cracking. The NPRM proposed to require repetitive ultrasonic 
inspections of the upper wing skin at certain engine strut positions 
for cracking; repetitive detailed and ultrasonic inspections of the 
strut lower spar fitting, diagonal brace strut end clevis, and diagonal 
brace wing attach end clevis for cracking; repetitive detailed 
inspections of lower link fitting at certain engine strut positions for 
cracking; and applicable on-condition actions.
    The FAA is issuing this AD to address undetected cracking in the 
upper wing skin, strut lower spar fitting, or clevis lugs at either end 
of the diagonal brace and lower link fitting. This condition, if not 
addressed, could adversely affect the structural integrity of the 
engine strut and may lead to the separation of the strut to wing box 
assembly.

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The FAA has considered the comments 
received. Boeing stated that it concurred with the NPRM.

[[Page 79414]]

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety and the public interest 
require adopting this final rule as proposed, except for minor 
editorial changes. The FAA has determined that these minor changes:
    <bullet> Are consistent with the intent that was proposed in the 
NPRM for addressing the unsafe condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM.

Related IBR Material Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019. The service information describes procedures 
for ultrasonic inspections of the upper wing skin at engine strut 
positions 1 through 4 for cracking; detailed and ultrasonic inspections 
of the strut lower spar fitting, diagonal brace strut end clevis, and 
diagonal brace wing attach end clevis for cracking; detailed 
inspections of lower link fitting at engine strut positions 1 through 4 
for cracking; and applicable on-condition actions. On-condition actions 
include 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.

Costs of Compliance

    The FAA estimates that this AD affects 125 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                      Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspections....................  9 work-hours x $85 per               $0  $765 per            $95,625 per
                                  hour = $765 per                          inspection cycle.   inspection cycle.
                                  inspection cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data that would enable the 
agency 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.
    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.

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):

2020-21-16 The Boeing Company: Amendment 39-21289; Docket No. FAA-
2020-0573; Product Identifier 2020-NM-078-AD.

(a) Effective Date

    This AD is effective January 14, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP 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 a determination that the upper wing skin 
at engine nacelle attachment points may be subject to undetected 
cracking. The FAA is issuing this AD to address undetected cracking 
in the upper wing skin, strut lower spar fitting, or clevis lugs at 
either end of the diagonal brace and lower link fitting. This 
condition, if not addressed, could adversely affect the structural 
integrity of the engine strut and may lead to the separation of the 
strut to wing box assembly.

(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 Bulletin 747-57A2363 RB, dated December 23, 2019, 
do all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
747-57A2363 RB, dated December 23, 2019.

    Note 1 to paragraph (g):  Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
747-57A2363, dated December 23, 2019, which is referred to in Boeing 
Alert Requirements Bulletin 747-57A2363 RB, dated December 23, 2019.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019, uses the phrase ``the original issue date 
of Requirements Bulletin 747-57A2363

[[Page 79415]]

RB,'' this AD requires using ``the effective date of this AD.''
    (2) Where Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019, specifies contacting Boeing for repair 
instructions: This AD requires doing the repair before further 
flight 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 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, 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 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 Eric Lin, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3523; 
email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (k)(3) and (4) of this AD.

(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 747-57A2363 RB, dated 
December 23, 2019.
    (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 [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on October 7, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-27006 Filed 12-9-20; 8:45 am]
BILLING CODE 4910-13-P


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Source SHA-256
f523ae7b31e35c73d5e5c69884a89e6bd6b384004c0576991d7d4fbac36677a2
Text SHA-256
32eda888476089a149a4e7c57d8d80bf96b14cb091eade731914daa44d589769

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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.

The collection uses 33 explicit annual source snapshots. Source captures and operative-text qualifications have separate states. Missing information remains unknown.