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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- 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.