AD 2010-20-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-400 Series | Airworthiness Directives; The Boeing Company Model 747-400, 747- 400D, and 747-400F Series Airplanes |
| aircraft | The Boeing Company | 747-400D Series | Airworthiness Directives; The Boeing Company Model 747-400, 747- 400D, and 747-400F Series Airplanes |
| aircraft | The Boeing Company | 747-400F Series | Airworthiness Directives; The Boeing Company Model 747-400, 747- 400D, and 747-400F Series Airplanes |
Unsafe Condition
An electrical hot short from a source outside the fuel quantity indicating system (FQIS) to the densitometer wiring can cause failure of the FQIS densitometer resistors, resulting in an ignition source inside the center or horizontal stabilizer fuel tanks. An ignition source combined with flammable fuel vapors could cause a fuel tank explosion and loss of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install a hot short protector (HSP) for the FQIS of the center fuel tank and, for certain airplanes, the horizontal stabilizer fuel tank according to the service bulletins. Use Boeing Service Bulletin 747-28A2266, Revision 1 and Alert Service Bulletin 747-28A2267 as applicable.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the compliance times specified in the AD, which is effective November 5, 2010.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 747-400, 747-400D, and 747-400F series airplanes certificated in any category, as identified in Boeing Service Bulletins 747-28A2266 (Rev 1) and 747-28A2267.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are adopting a new airworthiness directive (AD) for Model 747-400, 747-400D, and 747-400F series airplanes. This AD requires installing a hot short protector (HSP) for the fuel quantity indicating system (FQIS) of the center fuel tank and, for certain airplanes, the horizontal stabilizer fuel tank. This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to prevent an electrical hot short from a source outside the FQIS to the densitometer wiring from causing failure of the FQIS densitometer resistors, which could result in an ignition source inside the center or horizontal stabilizer fuel tanks. An ignition source, in combination with flammable fuel vapors, could result in a fuel tank explosion and consequent loss of the airplane. This AD is effective November 5, 2010. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the AD as of November 5, 2010.
Document Text
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[Federal Register Volume 75, Number 190 (Friday, October 1, 2010)]
[Rules and Regulations]
[Pages 60614-60616]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2010-24169]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0035; Directorate Identifier 2009-NM-066-AD;
Amendment 39-16447; AD 2010-20-12]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Model 747-400, 747-
400D, and 747-400F Series Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for Model
747-400, 747-400D, and 747-400F series airplanes. This AD requires
installing a hot short protector (HSP) for the fuel quantity indicating
system (FQIS) of the center fuel tank and, for certain airplanes, the
horizontal stabilizer fuel tank. This AD results from fuel system
reviews conducted by the manufacturer. We are issuing this AD to
prevent an electrical hot short from a source outside the FQIS to the
densitometer wiring from causing failure of the FQIS densitometer
resistors, which could result in an ignition source inside the center
or horizontal stabilizer fuel tanks. An ignition source, in combination
with flammable fuel vapors, could result in a fuel tank explosion and
consequent loss of the airplane. This AD is effective November 5, 2010.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in the AD as of November 5,
2010.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail <a href="/cdn-cgi/l/email-protection#630e064d010c06000c0e23010c060a0d044d000c0e"><span class="__cf_email__" data-cfemail="305d551e525f55535f5d70525f55595e571e535f5d">[email protected]</span></a>;
Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (telephone 800-647-5527) is the Document Management
Facility, 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: Georgios Roussos, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6482; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an airworthiness directive (AD) that would apply to
certain Model 747-400, 747-400D, and 747-400F series airplanes. That
NPRM
[[Page 60615]]
was published in the Federal Register on February 11, 2010 (75 FR
6821). That NPRM proposed to require installing a hot short protector
for the fuel quantity indicating system of the center fuel tank and,
for certain airplanes, the horizontal stabilizer fuel tank.
Comments
We gave the public the opportunity to participate in developing
this AD. We considered the comments received from The Boeing Company.
Request To Revise Preamble of the NPRM
Boeing requests the following changes to sections of the preamble
of the NPRM:
<bullet> In the section ``Relevant Service Information,'' revise
``We have received Boeing Service Bulletin 74728A2266, Revision 1,
dated December 10, 2009 (for the CWTs)'' to ``We have received Boeing
Service Bulletin 74728A2266, Revision 1, dated December 10, 2009 (for
all airplanes),'' because there are no configurations of the Model 747-
400 without the center fuel tank.
<bullet> Revise ``Relevant Service Information'' to add the phrase
``(for airplanes with horizontal stabilizer tanks)'' to ``Boeing Alert
Service Bulletin 747-28A2267, dated December 18, 2008.'' Boeing states
that this service bulletin adds a hot short protector on the horizontal
stabilizer tank (HST).
We acknowledge the commenter's requests. While the commenter's
suggestions may clarify information that the NPRM contained, these
sections are not included in the final rule. As a result, we have not
changed the AD in regard to these issues.
Request To Clarify the FQIS Wire Separation Requirement
Boeing requests that we clarify the requirement of the FQIS wire
separation from the wiring of the other systems as a result of
implementing the actions required by this AD. Boeing requests that we
revise the Discussion section of the NPRM to state that after the
actions required by the AD are implemented, then no further actions are
required to separate the FQIS wire from the wiring of other systems.
We agree with the commenter that no action is required for the
undisturbed portion of the densitometer wiring from the HSP to the fuel
quantity processor unit at the electrical equipment bay. This final
rule requires the installation of the HSP according to the
accomplishment instructions of the applicable service bulletins. No
part of this AD implies or requires action for the undisturbed portion
of the densitometer wiring. Therefore, we have not changed the final
rule in regard to this issue.
Request To Add Service Bulletin to Credit Paragraph
Boeing requests that we revise paragraph (h) of the NPRM to include
Boeing Alert Service Bulletin 747-28A2266, Revision 1, dated December
10, 2009.
We do not agree to revise the AD, because such a revision is
unnecessary. Paragraph (h) of this AD exists to give credit for actions
accomplished before the effective date of this AD using Boeing Alert
Service Bulletin 747-28A2266, dated December 18, 2008, and paragraph
(g) of this AD requires that Revision 1 of this service bulletin is
used for the action specified in that paragraph. We have not changed
the AD in regard to this issue.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
the AD as proposed.
Costs of Compliance
We estimate that this AD affects 80 airplanes of U.S. registry. The
following table provides the estimated costs for U.S. operators to
comply with this AD.
Table--Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average labor
Action Work hours rate per hour Parts Cost per product Fleet cost
--------------------------------------------------------------------------------------------------------------------------------------------------------
Installation\1\..................... 6 to 17................ $85 $15,821 to $30,650..... $16,331 to $32,095..... $1,306,480 to
$2,567,600.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Work hours and parts costs depend on airplane configuration.
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.
We are 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) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979), 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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
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.
[[Page 60616]]
Sec. 39.13 [Amended]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2010-20-12 The Boeing Company: Amendment 39-16447; Docket No. FAA-
2010-0035; Directorate Identifier 2009-NM-066-AD.
Effective Date
(a) This AD is effective November 5, 2010.
Affected ADs
(b) None.
Applicability
(c) This AD applies to The Boeing Company Model 747-400, 747-
400D, and 747-400F series airplanes, certificated in any category;
as identified in the service bulletins listed in paragraphs (c)(1)
and (c)(2) of this AD.
(1) Boeing Service Bulletin 747-28A2266, Revision 1, dated
December 10, 2009.
(2) Boeing Alert Service Bulletin 747-28A2267, dated December
18, 2008.
Subject
(d) Air Transport Association (ATA) of America Code 28: Fuel.
Unsafe Condition
(e) This AD results from fuel system reviews conducted by the
manufacturer. The Federal Aviation Administration is issuing this AD
to prevent an electrical hot short from a source outside the fuel
quantity indicating system (FQIS) to the densitometer wiring from
causing failure of the FQIS densitometer resistors, which could
result in an ignition source inside the center or horizontal
stabilizer fuel tanks. An ignition source, in combination with
flammable fuel vapors, could result in a fuel tank explosion and
consequent loss of the airplane.
Compliance
(f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Installation of Hot Short Protector (HSP)
(g) Within 60 months after the effective date of this AD: Do the
applicable installations of the HSP specified in paragraphs (g)(1)
and (g)(2) of this AD.
Note 1: Boeing Service Bulletin 747-28A2266, Revision 1, dated
December 10, 2009; and Boeing Alert Service Bulletin 747-28A2267,
dated December 18, 2008; refer to Cinch Service Bulletin CN1036-28-
01, Revision C, dated January 18, 2007, as an additional source of
guidance for installing the HSP in the fuel tanks which must be done
before or concurrently with the actions specified in Boeing Service
Bulletin 747-28A2266, Revision 1, dated December 10, 2009; and
Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008.
(1) For all airplanes: Install the HSP in the center wing tank,
in accordance with the Accomplishment Instructions of Boeing Service
Bulletin 747-28A2266, Revision 1, dated December 10, 2009.
(2) For airplanes identified in Boeing Alert Service Bulletin
747-28A2267, dated December 18, 2008: Install the HSP in the
horizontal stabilizer tank, in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-28A2267, dated
December 18, 2008.
Credit for Installation Previously Accomplished in Accordance With
Previous Issue of Service Bulletin
(h) Actions accomplished before the effective date of this AD
according to Boeing Alert Service Bulletin 747-28A2266, dated
December 18, 2008, are considered acceptable for compliance with the
corresponding action specified in this AD, provided that Cinch
Service Bulletin CN1036-28-01, Revision C, dated January 18, 2007,
is used as an additional source of guidance.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. Send information to
ATTN: Georgios Roussos, Aerospace Engineer, Systems and Equipment
Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601
Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6482; fax (425) 917-6590. Or, e-mail information to <a href="/cdn-cgi/l/email-protection#142d39555a5939477175606078713955575b3955595b57394671656171676067547275753a737b62"><span class="__cf_email__" data-cfemail="dbe2f69a9596f688bebaafafb7bef69a9894f69a969498f689beaaaebea8afa89bbdbabaf5bcb4ad">[email protected]</span></a>.
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your principal maintenance inspector (PMI) or
principal avionics inspector (PAI), as appropriate, or lacking a
principal inspector, your local Flight Standards District Office.
The AMOC approval letter must specifically reference this AD.
Material Incorporated by Reference
(j) You must use Boeing Service Bulletin 747-28A2266, Revision
1, dated December 10, 2009; or Boeing Alert Service Bulletin 747-
28A2267, dated December 18, 2008; as applicable; to do the actions
required by this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone
206-544-5000, extension 1; fax 206-766-5680; e-mail
<a href="/cdn-cgi/l/email-protection#86ebe3a8e4e9e3e5e9ebc6e4e9e3efe8e1a8e5e9eb"><span class="__cf_email__" data-cfemail="95f8f0bbf7faf0f6faf8d5f7faf0fcfbf2bbf6faf8">[email protected]</span></a>; Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(3) You may review copies of the service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington. For information on the availability of this material at
the FAA, call 425-227-1221.
(4) You may also review copies of the 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, call 202-741-6030, or go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Issued in Renton, Washington, on September 16, 2010.
Robert D. Breneman,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2010-24169 Filed 9-30-10; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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