Airworthiness Directives; The Boeing Company Airplanes

[Federal Register Volume 87, Number 108 (Monday, June 6, 2022)]
[Rules and Regulations]
[Pages 34120-34125]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-12030]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0877; Project Identifier AD-2020-01316-T; 
Amendment 39-22049; AD 2022-10-11]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain The Boeing Company Model 747-100B SUD, 747-200B, 747-200C, 747-
200F, 747-300, 747SP, 747-400, 747-400D, and 747-400F series airplanes. 
This AD was prompted by a determination that a certain fastener type 
that penetrates the fuel tank walls has insufficient bond to the 
structure, and energy from a lightning strike or high-powered short 
circuit could cause arcing to occur at the ends of fasteners in the 
fuel tanks. This AD requires, for certain airplanes, reconfiguring the 
clamps of certain wire bundles, applying sealant to certain fasteners 
that penetrate the fuel tank walls, installing cushion clamps and 
polytetrafluoroethylene (TFE) sleeves, inspecting to determine if 
sealant was applied to certain fasteners, and

[[Page 34121]]

applying sealant if necessary. This AD also requires, for all 
airplanes, revising the maintenance or inspection program, as 
applicable, to incorporate new, more restrictive airworthiness 
limitations (AWLs). The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective July 11, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of July 11, 
2022.

ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 
90740-5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this service information at the 
FAA, Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability of 
this material at the FAA, call 206-231-3195. It is also available at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2021-0877.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0877; 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: Rose Len, Aerospace Engineer, 
Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3604; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to certain The Boeing 
Company Model 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 
747SP, 747-400, 747-400D, and 747-400F series airplanes. The NPRM 
published in the Federal Register on November 17, 2021 (86 FR 64085). 
The NPRM was prompted by a determination that a certain fastener type 
that penetrates the fuel tank walls has insufficient bond to the 
structure, and energy from a lightning strike or high-powered short 
circuit could cause arcing to occur at the ends of fasteners in the 
fuel tanks. In the NPRM, the FAA proposed to require, for certain 
airplanes, reconfiguring the clamps of certain wire bundles, applying 
sealant to certain fasteners that penetrate the fuel tank walls, 
installing cushion clamps and TFE sleeves, inspecting to determine if 
sealant was applied to certain fasteners, and applying sealant if 
necessary. In the NPRM, the FAA also proposed to require, for all 
airplanes, revising the maintenance or inspection program, as 
applicable, to incorporate new, more restrictive AWLs. The FAA is 
issuing this AD to address arcing in the event of a lightning strike or 
high-powered short circuit, which could result in a fuel tank explosion 
or fire.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from two commenters, Air Line Pilots 
Association, International (ALPA), and Boeing, who supported the NPRM 
without change.
    The FAA also received comments from United Parcel Service (UPS), 
who supported the general actions in the NPRM and provided comments on 
the AWLs and the inspections specified in the NPRM. The FAA also 
received comments from Delta Air Lines (Delta). The following presents 
the comments received on the NPRM and the FAA's response to each 
comment.

Request To Change the NPRM to a Supersedure

    Delta requested that the NPRM be changed to a supersedure of AD 
2007-20-01, Amendment 39-15211 (72 FR 54533, September 26, 2007) (AD 
2007-20-01). Delta stated that paragraph (f) of AD 2007-20-01 requires 
accomplishing Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 1, dated July 10, 2006; and Boeing Special Attention Service 
Bulletin 747-57-2326, dated January 4, 2007. Delta also stated that the 
NPRM would require new actions in accordance with the latest revisions 
of the same service information required in AD 2007-20-01. Delta 
concluded that it would make compliance simpler by having all of the 
work in one place and not split between multiple versions of the same 
bulletins, provided credit is given for accomplishment of Work Packages 
1 through 20 using previous revisions of Boeing Special Attention 
Service Bulletin 747-57-2327, Revision 8, dated November 13, 2020.
    The FAA disagrees with the request. The FAA considered superseding 
AD 2007-20-01 to mandate actions that are necessary to address Special 
Federal Aviation Regulation No. 88 (SFAR 88) that were unintentionally 
omitted from Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 1, dated July 10, 2006. However, the FAA reviewed Boeing 
Special Attention Service Bulletin 747-57-2327, Revision 8, dated 
November 13, 2020, and identified AD requirements for additional 
airplane groups and work packages. The FAA determined that a stand-
alone AD would be appropriate because the actions required by AD 2007-
20-01 have already been accomplished and paragraph (g) of this AD only 
applies to some of the airplanes identified in AD 2007-20-01. The 
additional work in Boeing Special Attention Service Bulletin 747-57-
2327, Revision 8, dated November 13, 2020, is only required for certain 
airplanes, as identified in paragraphs (g)(1) and (2) of this AD. In 
addition, the actions specified in paragraph (g)(3) of this AD, using 
Boeing Special Attention Service Bulletin 747-57-2326, Revision 1, 
dated January 31, 2008, are only required for certain airplanes. The 
FAA has not changed this AD in this regard.

Request To Revise Initial Compliance Time for an Airworthiness 
Limitation

    UPS requested that the initial compliance time in paragraph (h)(1) 
of the proposed AD be revised. UPS stated the compliance time should be 
within 12 years after incorporation of Boeing Special Attention Service 
Bulletin 747-57-2327, or within 24 months after the effective date of 
this AD, whichever occurs later. UPS stated the initial compliance time 
for AWL 28-AWL-33 is not stated in The Boeing Company 747-400 
Maintenance Planning Data (MPD) Document, Section 9, Airworthiness 
Limitations (AWLs) and Certification Maintenance Requirements (CMRs), 
D621U400-9, Revision February 2020. UPS noted that paragraph (h)(1) of 
the proposed AD states the initial compliance time is at the time in 
the MPD document or within 60 days. UPS stated that due to the age of 
the affected airplanes that many would have to comply within the 60-day 
initial compliance time, which would put an undue burden on operators 
because this task requires extensive access common to heavy 
maintenance.
    The FAA agrees to revise the initial compliance time. It was not 
the FAA's

[[Page 34122]]

intention to mandate the initial AWL No. 28-AWL-33 inspection tasks 
within 60 days after the effective date of this AD for operators that 
have not yet incorporated AWL No. 28-AWL-33 into the existing 
maintenance or inspection program, as applicable. However, the FAA 
disagrees with the compliance time proposed by UPS. The compliance time 
for AWL No. 28-AWL-33 depends on whether AWL No. 28-AWL-33 has already 
been incorporated into the operator's existing maintenance or 
inspection program, and on whether Boeing Special Attention Service 
Bulletin 747-57-2327 has been incorporated. AWL No. 28-AWL-33 applies 
to airplanes on which Boeing Special Attention Service Bulletin 747-57-
2327 has been incorporated and airplanes having line number 645 and on. 
The FAA has revised the initial compliance time in paragraph (h)(1) of 
this AD by making this distinction of whether AWL No. 28-AWL-33 was 
previously incorporated into the operator's maintenance or inspection 
program and allowing for a 12 month initial compliance time if certain 
conditions apply. The FAA also revised the text for the initial 
compliance time in paragraph (h)(1) of this AD by replacing the 
reference to ``the tasks'' with a reference to ``AWL No. 28-AWL-33'' as 
it is the only task. The other AWL items referenced in paragraph (h)(1) 
of this AD are Critical Design Configuration Control Limitations 
(CDCCLs).
    In addition, the FAA has revised the initial compliance time for 
AWL No. 28-AWL-25 in paragraph (h)(2) of this AD by making this 
distinction of whether AWL No. 28-AWL-25 was previously incorporated 
into the operator's maintenance or inspection program and allowing for 
a 12 month initial compliance time if certain conditions apply. The 
compliance time specified in the proposed AD for AWL No. 28-AWL-25 has 
a similar issue to the one for AWL No. 28-AWL-33. The FAA did not 
intend to mandate the initial AWL No. 28-AWL-25 inspection task within 
60 days after the effective date of this AD for operators that have not 
already incorporated the task into the operator's existing maintenance 
or inspection program. The FAA also revised the text for the initial 
compliance time in paragraph (h)(2) of this AD by replacing the 
reference to ``the tasks'' with a reference to ``AWL No. 28-AWL-25'' as 
it is the only task. The other AWL items referenced in paragraph (h)(2) 
of this AD are CDCCLs.

Request To Remove Inspection for Sealant

    UPS requested that the FAA remove paragraph (g)(2) of the proposed 
AD (which includes a requirement to inspect and seal the ends of 
certain fasteners inside the fuel tanks). UPS stated that AD 2007-20-01 
includes a requirement to seal the ends of certain fasteners inside the 
fuel tanks in accordance with Boeing Special Attention Service Bulletin 
747-57-2327, Revision 1, dated July 10, 2006. UPS stated that Step 5 of 
Figure 23 of Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 1, dated July 10, 2006, specifies to apply the fillet sealant 
on the fastener and refers to certain airplane maintenance manual (AMM) 
procedures. UPS also noted that CDCCL 28-AWL-37, added by paragraph (h) 
of the proposed AD, only checks for cracked or damaged sealant. UPS 
concluded that paragraph (g)(2) does not provide any additional 
improvement in the condition of the affected airplanes from that 
required by AD 2007-20-01, and therefore should not be required.
    The FAA disagrees with the request. The purpose of paragraph (g)(2) 
of this AD is to make sure that the fillet sealant on identified 
fasteners fully encapsulates those fasteners. Boeing Special Attention 
Service Bulletin 747-57-2327, Revision 1, dated July 10, 2006, does not 
specify to make sure that the fasteners are fully encapsulated with 
sealant. The AMM procedures are references only and therefore does not 
mandate that fasteners are fully encapsulated. Since Boeing Special 
Attention Service Bulletin 747-57-2327, Revision 8, dated November 13, 
2020, also does not specify to fully encapsulate the fasteners, the 
requirement in paragraph (g)(2) of this AD includes an exception that 
states where note (f) of Figure 23 specifies to ``make sure to apply 
the fillet sealant on the fastener,'' this AD requires applying the 
fillet sealant to fully encapsulate the fastener penetrating the fuel 
tank. The FAA has not changed this AD in this regard.

Request To Provide Credit for Previous Actions

    UPS requested that paragraph (j) of the proposed AD be revised to 
give credit for previous actions accomplished using Boeing Special 
Attention Service Bulletin 747-57-2326, Revision 1, dated January 31, 
2008. UPS stated that it performed the requirement to seal the ends of 
certain fasteners using Boeing Special Attention Service Bulletin 747-
57-2326, Revision 1, dated January 31, 2008, as an alternative method 
of compliance to AD 2007-20-01 (which mandated Boeing Special Attention 
Service Bulletin 747-57-2326, dated January 4, 2007). UPS stated it 
does not believe they need to go back and verify that previously 
accomplished actions were done as directed. UPS notes that paragraph 
(f) of the proposed AD does state to comply with the AD unless already 
done, but paragraph (j) of the proposed AD does not give credit for 
previous actions accomplished using Boeing Special Attention Service 
Bulletin 747-57-2326, Revision 1, dated January 31, 2008. UPS also 
stated that if credit is not given, the FAA should provide an 
explanation as to why operators need to go back and verify that 
previous AD required actions were accomplished as directed.
    The FAA agrees that operators that sealed the fasteners using 
Boeing Special Attention Service Bulletin 747-57-2326, Revision 1, 
dated January 31, 2008, do not have to go back and verify that all 
fasteners identified in Figures 4 and 5 of Boeing Special Attention 
Service Bulletin 747-57-2326, Revision 1, dated January 31, 2008, were 
sealed in accordance with Figure 1 of that same service bulletin. Only 
airplanes on which the fasteners were sealed using Boeing Special 
Attention Service Bulletin 747-57-2326, dated January 4, 2007, must be 
inspected and the fasteners sealed if necessary. The FAA has revised 
paragraph (g)(3) of this AD accordingly.
    The FAA also notes there is no need to provide credit in paragraph 
(j) of the AD for actions taken using Boeing Special Attention Service 
Bulletin 747-57-2326, Revision 1, dated January 31, 2008, because 
paragraph (f) of the AD mandates compliance with this AD within the 
compliance times specified, unless already done.

Conclusion

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

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Special Attention Service Bulletin 747-57-
2327, Revision 8, dated November 13, 2020. This service information 
describes procedures for reconfiguring the clamps

[[Page 34123]]

of certain wire bundles, applying sealant to certain fasteners that 
penetrate the fuel tank walls, and installing cushion clamps and TFE 
sleeves on the wire bundles of the front spars and rear spars of the 
wings.
    The FAA also reviewed Boeing Special Attention Service Bulletin 
747-57-2326, Revision 1, dated January 31, 2008. This service 
information describes procedures for, among other actions, applying 
sealant to certain fasteners.
    The FAA also reviewed The Boeing Company 747-400 Maintenance 
Planning Data (MPD) Document, Section 9, Airworthiness Limitations 
(AWLs) and Certification Maintenance Requirements (CMRs), D621U400-9, 
Revision February 2020, which includes revised AWL tasks 28-AWL-33, 28-
AWL-34, and 28-AWL-37; and The Boeing Company 747-100/200/300/SP/SR 
Airworthiness Limitations (AWLs) and Certification Maintenance 
Requirements (CMRs), D6-13747-CMR, Revision September 2020, which 
includes revised AWL tasks 28-AWL-25, 28-AWL-27, and 28-AWL-28. The 
revised AWL tasks describe fuel airworthiness limitation items (ALIs) 
and CDCCLs that address fuel tank systems. These documents are distinct 
because they apply to different airplane models. The new AWLs include:
    <bullet> An ALI (periodic inspections) of the cushion clamps and 
teflon sleeving installed on out-of-tank wire bundles installed on 
brackets that are mounted directly on the fuel tanks;
    <bullet> A CDCCL for the cushion clamps and teflon sleeving 
installed on out-of-tank wire bundles installed on brackets that are 
mounted directly on the fuel tanks; and
    <bullet> A CDCCL for lightning, fault current or hot short 
protection features.
    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 affects 104 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
               Action                      Labor cost                  Parts cost                 Cost per  product           Cost on U.S.  operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Reconfiguring clamps, inspections,   Up to 30 work-hours x   Up to $2,004.................  Up to $4,554.................  Up to $473,616.
 applying sealant, and installing     $85 per hour = Up to
 clamps and TFE sleeves.              $2,550.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The FAA has determined that revising the maintenance or inspection 
program takes an average of 90 work-hours per operator, although the 
agency recognizes that this number may vary from operator to operator. 
Since operators incorporate maintenance or inspection program changes 
for their affected fleet(s), the FAA has determined that a per-operator 
estimate is more accurate than a per-airplane estimate. Therefore, the 
agency estimates the average total cost per operator to be $7,650 (90 
work-hours x $85 per work-hour).
    The FAA estimates the following costs to do any necessary 
application of sealant that would be required based on the results of 
the inspections. The agency has no way of determining the number of 
aircraft that might need this action:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                            Action                                Labor cost       Parts cost        product
----------------------------------------------------------------------------------------------------------------
Applying sealant.............................................  Up to 102 work-    Up to $6,813   Up to $15,483.
                                                               hours x $85 per
                                                                 hour = Up to
                                                                       $8,670
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all of the costs of 
this AD may be covered under warranty, thereby reducing the cost impact 
on affected operators.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    The FAA is issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: General requirements. 
Under that section, Congress charges the FAA with promoting safe flight 
of civil aircraft in air commerce by prescribing regulations for 
practices, methods, and procedures the Administrator finds necessary 
for safety in air commerce. This regulation is within the scope of that 
authority because it addresses an unsafe condition that is likely to 
exist or develop on products identified in this rulemaking action.

Regulatory Findings

    This AD will not have federalism implications under Executive Order 
13132. This AD will not have a substantial direct effect on the States, 
on the relationship between the national government and the States, or 
on the distribution of power and responsibilities among the various 
levels of government.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Will not affect intrastate aviation in Alaska, and
    (3) Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

[[Page 34124]]

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13   [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2022-10-11 The Boeing Company: Amendment 39-22049; Docket No. FAA-
2021-0877; Project Identifier AD-2020-01316-T.

(a) Effective Date

    This airworthiness directive (AD) is effective July 11, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 747-100B SUD, 747-
200B, 747-200C, 747-200F, 747-300, 747SP, 747-400, 747-400D, and 
747-400F series airplanes, certificated in any category, having line 
numbers 645 and subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 28, Fuel; 57, 
Wings.

(e) Unsafe Condition

    This AD was prompted by the FAA's analysis of the fuel system 
reviews conducted by the manufacturer. The FAA is issuing this AD to 
address arcing in the event of a lightning strike or high-powered 
short circuit, which could result in a fuel tank explosion or fire.

(f) Compliance

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

(g) Reconfiguration of Wire Bundle Clamps, Sealant Application, 
Installation of Clamps and Sleeves, Inspections, and Corrective Actions

    (1) For Group 1 through 9, 11, and 16 through 45 airplanes 
identified in Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 8, dated November 13, 2020: Within 60 months after the 
effective date of this AD, reconfigure the clamps of the specified 
wire bundles, apply sealant to the specified fasteners that 
penetrate the fuel tank walls, and install cushion clamps and 
polytetrafluoroethylene (TFE) sleeves on the wire bundles of the 
front spars and rear spars of the wings, as applicable, in 
accordance with Work Packages 13 through 21, as applicable, of the 
Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 747-57-2327, Revision 8, dated November 13, 2020.
    (2) For airplanes on which the actions specified in Work Package 
7, 8, or 9 of Boeing Special Attention Service Bulletin 747-57-2327 
have been done: Within 60 months after the effective date of this 
AD, inspect to determine if the fillet sealant identified in step 5 
of Figure 23 of Boeing Special Attention Service Bulletin 747-57-
2327, Revision 8, dated November 13, 2020, was applied to fully 
encapsulate the fastener penetrating the fuel tank; and if the 
sealant does not fully encapsulate the fastener, before further 
flight, apply sealant as specified in step 5 of Figure 23, except 
where note (f) of Figure 23 specifies to ``make sure to apply the 
fillet sealant on the fastener,'' this AD requires applying the 
fillet sealant to fully encapsulate the fastener penetrating the 
fuel tank.
    (3) For Group 2 airplanes identified in Boeing Special Attention 
Service Bulletin 747-57-2326, Revision 1, dated January 31, 2008, on 
which fasteners were sealed using Boeing Special Attention Service 
Bulletin 747-57-2326, dated January 4, 2007: Within 60 months after 
the effective date of this AD, inspect to determine if all fasteners 
identified in Figures 4 and 5 of Boeing Special Attention Service 
Bulletin 747-57-2326, Revision 1, dated January 31, 2008, have been 
sealed; and if any fasteners are not sealed, before further flight, 
apply sealant in accordance with Figure 1 of Boeing Special 
Attention Service Bulletin 747-57-2326, Revision 1, dated January 
31, 2008.

(h) Maintenance or Inspection Program Revision

    (1) For Model 747-400, 747-400D, and 747-400F series airplanes: 
Within 60 days after the effective date of this AD: Revise the 
existing maintenance or inspection program, as applicable, by 
incorporating the information in airworthiness limitations (AWLs) 
28-AWL-33, 28-AWL-34, and 28-AWL-37 of The Boeing Company 747-400 
Maintenance Planning Data (MPD) Document, Section 9, Airworthiness 
Limitations (AWLs) and Certification Maintenance Requirements 
(CMRs), D621U400-9, Revision February 2020. The initial compliance 
time for doing AWL No. 28-AWL-33, ``Cushion Clamps and Teflon 
Sleeving Installed on Out-of-Tank Wire Bundles Installed on Brackets 
that are Mounted Directly on the Fuel Tanks,'' is at the applicable 
time specified in paragraphs (h)(1)(i) or (ii) of this AD.
    (i) For airplanes that did not have any version of AWL No. 28-
AWL-33 in the existing maintenance or inspection program before the 
effective date of this AD: Within 144 months since issuance of the 
original airworthiness certificate or original export certificate of 
airworthiness, within 144 months since Boeing Special Attention 
Bulletin 747-57-2327 was incorporated, or within 12 months after the 
effective date of this AD, whichever occurs latest.
    (ii) For airplanes not identified in paragraph (h)(1)(i) of this 
AD: Within 144 months since AWL No. 28-AWL-33 was incorporated into 
the existing maintenance or inspection program, or within 144 months 
after the most recent inspection was performed as specified in AWL 
No. 28-AWL-33, whichever occurs later.
    (2) For Model 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-
300, and 747SP series airplanes: Within 60 days after the effective 
date of this AD, revise the existing maintenance or inspection 
program, as applicable, by incorporating the information in AWLs 28-
AWL-25, 28-AWL-27, and 28-AWL-28 of The Boeing Company 747-100/200/
300/SP/SR Airworthiness Limitations (AWLs) and Certification 
Maintenance Requirements (CMRs), D6-13747-CMR, Revision September 
2020; except where the ``Applicability'' of AWLs 28-AWL-25 and 28-
AWL-27 specifies ``ALL'' and ``NOTE,'' replace ``ALL'' and ``NOTE'' 
with ``Airplanes L/N 645 and on'' and remove the ``Applicability 
Note'' from the Description column of 28-AWL-25 and 28-AWL-27. The 
initial compliance time for doing AWL No. 28 AWL-25, ``Cushion 
Clamps and Teflon Sleeving Installed on Out-of-Tank Wire Bundles 
Installed on Brackets that are Mounted Directly on the Fuel Tanks,'' 
is at the applicable time specified in paragraphs (h)(2)(i) or (ii) 
of this AD.
    (i) For airplanes that did not have any version of AWL No. 28-
AWL-25 in the existing maintenance or inspection program before the 
effective date of this AD: Within 144 months since issuance of the 
original airworthiness certificate or original export certificate of 
airworthiness, within 144 months since Boeing Special Attention 
Bulletin 747-57-2327 was incorporated, or within 12 months after the 
effective date of this AD, whichever occurs latest.
    (ii) For airplanes not identified in paragraph (h)(2)(i) of this 
AD: Within 144 months since AWL No. 28-AWL-25 was incorporated into 
the maintenance or inspection program, or within 144 months after 
the most recent inspection was performed as specified in AWL No. 28-
AWL-25, whichever occurs later.

(i) No Alternative Actions, Intervals, and Critical Design 
Configuration Control Limitations (CDCCLs)

    After the maintenance or inspection program has been revised as 
required by paragraph (h)(1) or (2) of this AD, no alternative 
actions (e.g., inspections), intervals, and CDCCLs may be used 
unless the actions, intervals, and CDCCLs are approved as an 
alternative method of compliance (AMOC) in accordance with the 
procedures specified in paragraph (k) of this AD.

(j) Credit for Previous Actions

    (1) This paragraph provides credit for the Work Package 13 
actions specified in paragraph (g)(1) of this AD, if those actions 
were performed before the effective date of this AD using the 
service information specified in paragraphs (j)(1)(i) through (iv) 
of this AD.

[[Page 34125]]

    (i) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 4, dated August 26, 2010.
    (ii) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 5, dated September 20, 2011.
    (iii) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 6, dated February 21, 2013.
    (iv) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 7, dated November 30, 2017.
    (2) This paragraph provides credit for the Work Package 14, 15, 
and 16 actions specified in paragraph (g)(1) of this AD, if those 
actions were performed before the effective date of this AD using 
the service information specified in paragraphs (j)(2)(i) through 
(iii) of this AD.
    (i) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 5, dated September 20, 2011.
    (ii) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 6, dated February 21, 2013.
    (iii) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 7, dated November 30, 2017.
    (3) This paragraph provides credit for the Work Package 17 
actions specified in paragraph (g)(1) of this AD, if those actions 
were performed before the effective date of this AD using the 
service information specified in paragraphs (j)(3)(i) or (ii) of 
this AD.
    (i) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 6, dated February 21, 2013.
    (ii) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 7, dated November 30, 2017.
    (4) This paragraph provides credit for the Work Package 18, 19, 
and 20 actions specified in paragraph (g)(1) of this AD, if those 
actions were performed before the effective date of this AD using 
Boeing Special Attention Service Bulletin 747-57-2327, Revision 7, 
dated November 30, 2017.

(k) 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 (l)(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.

(l) Related Information

    (1) For more information about this AD, contact Rose Len, 
Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch, 
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3604; email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (m)(3) and (4) of this AD.

(m) 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 Special Attention Service Bulletin 747-57-2326, 
Revision 1, dated January 31, 2008.
    (ii) Boeing Special Attention Service Bulletin 747-57-2327, 
Revision 8, dated November 13, 2020.
    (iii) The Boeing Company 747-100/200/300/SP/SR Airworthiness 
Limitations (AWLs) and Certification Maintenance Requirements 
(CMRs), D6-13747-CMR, Revision September 2020.
    (iv) The Boeing Company 747-400 Maintenance Planning Data (MPD) 
Document, Section 9, Airworthiness Limitations (AWLs) and 
Certification Maintenance Requirements (CMRs), D621U400-9, Revision 
February 2020.
    (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. You may view this service information at the 
FAA, Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA.
    (4) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on May 6, 2022.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2022-12030 Filed 6-3-22; 8:45 am]
BILLING CODE 4910-13-P

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