Published 2021-08-31 · Federal Register document 2021-18705
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, -100B, -100B SUD, -200B, -200C, - 200F, -300, -400, -400D, -400F, 747SR, and 747SP airplanes. This AD was prompted by reports of cracks found in the front spar shear tie and at the intercostal lug fitting at certain locations. This AD requires repetitive detailed and surface high frequency eddy current (HFEC) inspections of the front spar shear tie and intercostal lug fitting at certain locations for any 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 2026-09-03T22:24:08.106391+00:00. The title, summary and date are source facts.
- Source revision
- federal_register_ad_metadata_2021-9c919420683447c6
- Source row
- results[310]
- Raw source SHA-256
- 9c919420683447c683ad0c877cb886e341c11862be32b47c536a001b1d76dcb5
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 2021-17-06
- Effective date printed in this edition
- 2021-10-05
Read 11 complete recorded clauses
Effective Date
(a) Effective Date
This airworthiness directive (AD) is effective October 5, 2021.
Exact source excerpt. Text positions 10322–10411, end exclusive, in the original decoded publication. SHA-256: e98fda833eb82745af1318b144837fbfc0d8f4e034ad01438d24e2927f86fd25
Affected ADs
(b) Affected ADs
None.
Exact source excerpt. Text positions 10411–10440, 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, -100B,
-100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, 747SR, and
747SP airplanes, certificated in any category.
Exact source excerpt. Text positions 10440–10646, end exclusive, in the original decoded publication. SHA-256: a591169fdd5d5e259d028447cf25111bccf21ef88f3094b0f3018941d9595933
Subject
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
Exact source excerpt. Text positions 10646–10726, end exclusive, in the original decoded publication. SHA-256: 297e69b8a6e159f28612e8bd82a91daa2fd8fd1d9d38af67161f67738908fa6c
Unsafe Condition
(e) Unsafe Condition
This AD was prompted by reports of cracks in the station (STA)
1000 front spar shear tie at the left and right side buttock line
(BL) 11.33, BL 33.99, BL 57.50, and BL 75.92, and in the intercostal
lug fitting at the left and right side BL 11.33. The FAA is issuing
this AD to address any cracking in these areas that could result in
the loss of limit load capability in a principal structural element,
the potential inability to restrain the cargo for certain cargo
configurations, and the potential for a center fuel tank rupture for
certain cargo configurations under limit load conditions, which
could adversely affect the structural integrity of the airplane.
Exact source excerpt. Text positions 10726–11427, end exclusive, in the original decoded publication. SHA-256: 44ecf67b7c85ea14c89b2450ddb0df9c2d657e8f20ac1d0a66dd2d802ce6a0b3
Compliance
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
Exact source excerpt. Text positions 11427–11529, 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 747-53A2904 RB, dated December 16, 2020,
do all applicable actions identified in, and in accordance with, the
Accomplishment Instructions of Boeing Alert Requirements Bulletin
747-53A2904 RB, dated December 16, 2020.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
747-53A2904, dated December 16, 2020, which is referred to in Boeing
Alert Requirements Bulletin 747-53A2904 RB, dated December 16, 2020.
Exact source excerpt. Text positions 11529–12206, end exclusive, in the original decoded publication. SHA-256: 8dc6b7b371d3a27b9bb2b9b87626933998fb9ce7f9a9d452e712d0bd1fa5cba7
Exceptions to Service Information Specifications
(h) Exceptions to Service Information Specifications
(1) Where Boeing Alert Requirements Bulletin 747-53A2904 RB,
dated December 16, 2020, uses the phrase ``the original issue date
of Requirements Bulletin 747-53A2904 RB,'' this AD requires using
``the effective date of this AD.''
(2) Where Boeing Alert Requirements Bulletin 747-53A2904 RB,
dated December 16, 2020, specifies contacting Boeing for repair
instructions: This AD requires doing the repair using a method
approved in accordance with the procedures specified in paragraph
(i) of this AD.
[[Page 48485]]
Exact source excerpt. Text positions 12206–12791, end exclusive, in the original decoded publication. SHA-256: 41299cd37b9dc37e45bae3fb91e96425ddb122ddabbd156c10887ef2f81ab0df
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 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 Related Information. 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.
Exact source excerpt. Text positions 12791–14013, end exclusive, in the original decoded publication. SHA-256: 3dd0a5d02c3800cdd23a57b2d083e3c33fca479fb024fd831e687fa11b0469f5
Related Information
(j) Related Information
(1) For more information about this AD, contact Stefanie Roesli,
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3964;
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 14013–14444, end exclusive, in the original decoded publication. SHA-256: 7ab1c02193464581b8118c91fcbf7f8bc83757ae5a131792bc61fc35ca824058
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 747-53A2904 RB, dated
December 16, 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.
Exact source excerpt. Text positions 14444–15723, end exclusive, in the original decoded publication. SHA-256: fbf9555b02fac1b58242af33e3d458661947de704823229ffb735b88cd454024
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 2021-17-06 · 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.
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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: 06cc5740f024ae938101328278f4a349fe482f6f5e8f1472fad4750e469d1d98. Source manifest: f643445b18c67859a114cf71be84f832dafd5be8a13e8e7d97e3566b7b4a73c5.
Official source · 2021-08-31
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 86, Number 166 (Tuesday, August 31, 2021)]
[Rules and Regulations]
[Pages 48483-48485]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-18705]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
========================================================================
Federal Register / Vol. 86, No. 166 / Tuesday, August 31, 2021 /
Rules and Regulations
[[Page 48483]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0376; Project Identifier AD-2021-00062-T;
Amendment 39-21689; AD 2021-17-06]
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, -100B, -100B SUD, -200B, -200C, -
200F, -300, -400, -400D, -400F, 747SR, and 747SP airplanes. This AD was
prompted by reports of cracks found in the front spar shear tie and at
the intercostal lug fitting at certain locations. This AD requires
repetitive detailed and surface high frequency eddy current (HFEC)
inspections of the front spar shear tie and intercostal lug fitting at
certain locations for any 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 October 5, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of October 5,
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 at
https://www.regulations.gov by searching for and locating Docket No.
FAA-2021-0376.
Examining the AD Docket
You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0376; 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: Stefanie Roesli, Aerospace Engineer,
Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des
Moines, WA 98198; phone and fax: 206-231-3964; 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 all The Boeing Company
Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -
400D, -400F, 747SR, and 747SP airplanes. The NPRM published in the
Federal Register on June 7, 2021 (86 FR 30216). The NPRM was prompted
by reports of cracks found in the front spar shear tie and at the
intercostal lug fitting at certain locations. In the NPRM, the FAA
proposed to require repetitive detailed and surface HFEC inspections of
the front spar shear tie and intercostal lug fitting at certain
locations for any cracking, and applicable on-condition actions. The
FAA is issuing this AD to address any cracking in these areas that
could result in the loss of limit load capability in a principal
structural element, the potential inability to restrain the cargo for
certain cargo configurations, and the potential for a center fuel tank
rupture for certain cargo configurations under limit load conditions,
which could adversely affect the structural integrity of the airplane.
Discussion of Final Airworthiness Directive
Comments
The FAA received a comment from Boeing who supported the NPRM
without change.
Conclusion
The FAA reviewed the relevant data, considered the comment
received, and determined that air safety requires adopting this AD as
proposed. Except for minor editorial changes, 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 747-53A2904 RB,
dated December 16, 2020. This service information specifies procedures
for repetitive detailed and surface HFEC inspections of the station
1000 front spar shear tie at the left and right side buttock line (BL)
11.33, BL 33.99, BL 57.50, and BL 75.92, and of the intercostal lug
fitting at the left and right side BL 11.33, for any cracking, and
applicable on-condition actions. On-condition actions include repair,
installing a new front spar shear tie, and installing a new intercostal
lug fitting. 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.
Costs of Compliance
The FAA estimates that this AD will affect 117 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
[[Page 48484]]
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Inspections................ Up to 314 work-hours $0 Up to $26,690........ Up to $3,122,730.
x $85 per hour = Up
to $26,690.
----------------------------------------------------------------------------------------------------------------
The FAA estimates the following costs to do any necessary
installations and repairs 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 installations and repairs:
On-Condition Costs
------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
------------------------------------------------------------------------
Installations........ Up to 368 work- Up to $38,446 Up to $69,726.
hour x $85 per (for shear
hour = Up to ties and
$31,280. intercostal
lug fittings).
------------------------------------------------------------------------
The FAA has received no definitive data on which to base the cost
estimates for the repairs 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.
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:
2021-17-06 The Boeing Company: Amendment 39-21689; Docket No. FAA-
2021-0376; Project Identifier AD-2021-00062-T.
(a) Effective Date
This airworthiness directive (AD) is effective October 5, 2021.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 747-100, -100B,
-100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, 747SR, and
747SP airplanes, certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by reports of cracks in the station (STA)
1000 front spar shear tie at the left and right side buttock line
(BL) 11.33, BL 33.99, BL 57.50, and BL 75.92, and in the intercostal
lug fitting at the left and right side BL 11.33. The FAA is issuing
this AD to address any cracking in these areas that could result in
the loss of limit load capability in a principal structural element,
the potential inability to restrain the cargo for certain cargo
configurations, and the potential for a center fuel tank rupture for
certain cargo configurations under limit load conditions, which
could adversely affect the 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 Bulletin 747-53A2904 RB, dated December 16, 2020,
do all applicable actions identified in, and in accordance with, the
Accomplishment Instructions of Boeing Alert Requirements Bulletin
747-53A2904 RB, dated December 16, 2020.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
747-53A2904, dated December 16, 2020, which is referred to in Boeing
Alert Requirements Bulletin 747-53A2904 RB, dated December 16, 2020.
(h) Exceptions to Service Information Specifications
(1) Where Boeing Alert Requirements Bulletin 747-53A2904 RB,
dated December 16, 2020, uses the phrase ``the original issue date
of Requirements Bulletin 747-53A2904 RB,'' this AD requires using
``the effective date of this AD.''
(2) Where Boeing Alert Requirements Bulletin 747-53A2904 RB,
dated December 16, 2020, specifies contacting Boeing for repair
instructions: This AD requires doing the repair using a method
approved in accordance with the procedures specified in paragraph
(i) of this AD.
[[Page 48485]]
(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 Related Information. 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 Stefanie Roesli,
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3964;
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 747-53A2904 RB, dated
December 16, 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 August 7, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness
Division, Aircraft Certification Service.
[FR Doc. 2021-18705 Filed 8-30-21; 8:45 am]
BILLING CODE 4910-13-P
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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.
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