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Published 2012-03-20 · Federal Register document 2012-6116

Airworthiness Directives; The Boeing Company Airplanes

Publication summary

We are adopting a new airworthiness directive (AD) for certain 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 design review following a ground fire incident and reports of flammable fluid leaks from the wing leading edge area onto the engine exhaust area. This AD requires modifying the fluid drain path in the leading edge area of the wing. We are issuing this AD to prevent flammable fluid from leaking onto the engine exhaust nozzle, which could result in a fire.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:39.502075+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2012-08bffa249ae9a205
Source row
results[75]
Raw source SHA-256
08bffa249ae9a2053bbfc0d74663d089914e83fb91f9bc4c8409ea28239f6875

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2012-05-03
Effective date printed in this edition
2012-04-24
Read 11 complete recorded clauses
Effective Date
(a) Effective Date

    This AD is effective April 24, 2012.

Exact source excerpt. Text positions 12143–12205, end exclusive, in the original decoded publication. SHA-256: 0029194af4ca99538a9a101bac7c11dbf6e020caa26bae4d651ac7b2e7393009

Affected ADs
(b) Affected ADs

    None.

Exact source excerpt. Text positions 12205–12234, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0

Applicability wording · Applicability
(c) Applicability

    This AD applies to 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, as identified in Boeing Special Attention Service 
Bulletin 747-57-2332, Revision 1, dated July 25, 2011.

Exact source excerpt. Text positions 12234–12577, end exclusive, in the original decoded publication. SHA-256: e6f259cfe0f1d36d05b6b14d51cf470095d080b877bcc49ea057be265c015b92

Subject
(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 57, Wings.

Exact source excerpt. Text positions 12577–12694, end exclusive, in the original decoded publication. SHA-256: f43076ad1695c10a44c4bb69c7243af8d94773daee46e08e01ddc53c8b40de12

Unsafe Condition
(e) Unsafe Condition

    This AD was prompted by a design review following a ground fire 
incident and reports of flammable fluid leaks from the wing leading 
edge area onto the engine exhaust area. We are issuing this AD to 
prevent flammable fluid from leaking onto the engine exhaust nozzle, 
which could result in a fire.

Exact source excerpt. Text positions 12694–13022, end exclusive, in the original decoded publication. SHA-256: b09cdf6623ac161bd6468cc908b0322bd03e0d61013376dc66903035d8dc6382

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 13022–13124, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Leading Edge Installation
(g) Leading Edge Installation

    Within 60 months after the effective date of this AD, modify the 
fluid drain path in the leading edge area of the wing, in accordance 
with the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 747-57-2332, Revision 1, dated July 25, 2011.

Exact source excerpt. Text positions 13124–13425, end exclusive, in the original decoded publication. SHA-256: 6ee2e803621b45b480c1fc4ec8402d7d2231d5cb3d2d558b1233c513f4878f5f

Credit for Previous Actions
(h) Credit for Previous Actions

    This paragraph provides credit for modifications of the fluid 
drain path required by paragraph (g) of this AD, if the modification 
was performed before the effective date of this AD, using Boeing 
Special Attention Service Bulletin 747-57-2332, dated November 9, 
2010.

Exact source excerpt. Text positions 13425–13735, end exclusive, in the original decoded publication. SHA-256: 4057b152c0edc5b0f8794b93ed94cb40a2d62ee319a4c2ed4ce457dc1efee7c4

Alternative Methods of Compliance (AMOCs)
(i) Alternative Methods of Compliance (AMOCs)

    (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. 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 ACO, send it to the 
attention of the person identified in the Related Information 
section 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 structural repairs required by this AD if it is approved by 
the Boeing Commercial Airplanes Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Seattle 
ACO to make those findings. For a repair method to be approved, the 
repair must meet the certification basis of the airplane and the 
approval must specifically refer to this AD.

Exact source excerpt. Text positions 13735–14973, end exclusive, in the original decoded publication. SHA-256: 279cd441a2388d2c699862b76fe221cf2998d735eb6d545fe177fe497a3af42e

Related Information
(j) Related Information

    For more information about this AD, contact Tung Tran, Aerospace 
Engineer, Propulsion Branch, ANM-140S, Seattle Aircraft 
Certification Office (ACO), FAA, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; phone: 425-917-6505; fax: 425-917-6590; 
email: [email protected].

Exact source excerpt. Text positions 14973–15280, end exclusive, in the original decoded publication. SHA-256: 52696c3f318e67e735be92a853d49af6a2ab4cc8f5193f2a65976e88dba94f3c

Material Incorporated by Reference
(k) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) of the following under 5 U.S.C. 552(a) and 1 CFR 
part 51:
    (i) Boeing Special Attention Service Bulletin 747-57-2332, 
Revision 1, dated July 25, 2011.
    (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; phone: 206-
544-5000, extension 1; fax: 206-766-5680; email: 
[email protected]; Internet: https://www.myboeingfleet.com.
    (3) You may review copies of the referenced 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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 15280–16560, end exclusive, in the original decoded publication. SHA-256: c981d3292b0e5a78bd9ed6a12ce34b87f4956c91bfde7a9d82f5f8da9126d1ad

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 2012-05-03 · 1 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: d1165b568a7f8887e48f42ac5c611d315a8a55dd48cbf3a95dd3c844ecec0e0a. Source manifest: f9367ad74ff7637e02d9c90f6683fbc045a16cee3a96223af7ea3a021fda7846.

Official source · 2012-03-20

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 77, Number 54 (Tuesday, March 20, 2012)]
[Rules and Regulations]
[Pages 16143-16145]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-6116]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0566; Directorate Identifier 2010-NM-271-AD; 
Amendment 39-16975; AD 2012-05-03]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
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 design review 
following a ground fire incident and reports of flammable fluid leaks 
from the wing leading edge area onto the engine exhaust area. This AD 
requires modifying the fluid drain path in the leading edge area of the 
wing. We are issuing this AD to prevent flammable fluid from leaking 
onto the engine exhaust nozzle, which could result in a fire.

DATES: This AD is effective April 24, 2012.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of April 24, 
2012.

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; phone: 206-
544-5000, extension 1; fax: 206-766-5680; email: [email protected]; 
Internet: https://www.myboeingfleet.com. You may review copies of the 
referenced 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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; 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 (phone: 800-647-5527) is 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: Tung Tran, Aerospace Engineer, 
Propulsion Branch, ANM-140S, Seattle Aircraft Certification Office 
(ACO), FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 
425-917-6505; fax: 425-917-6590; email: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM published in the Federal Register on June 14, 2011 (76 FR 
34625). That NPRM proposed to require modifying the fluid drain path in 
the leading edge area of the wing.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
(76 FR 34625, June 14, 2011) and the FAA's response to each comment.

Request To Withdraw NPRM (76 FR 34625, June 14, 2011)

    KLM Royal Dutch Airlines (KLM) requested we reassess the necessity 
for Boeing Special Attention Service Bulletin 747-57-2332, dated 
November 9, 2010; the NPRM (76 FR 34625, June 14, 2011); and the future 
AD. KLM stated the Model 747-400 world fleet (as reported by Boeing), 
as well as the KLM fleet, has had no problems with the issue described 
by the NPRM; and Model 747-400 airplanes have no slat cans or 
comparable mechanical construction and are therefore not subject to the 
unsafe condition. KLM also stated that modifying the drain path away 
from the pylon on the outboard side of the pylon will not result in an 
improvement, since the wing leading edge is installed at an angle, so 
the fuel still can flow towards the engine by gravity after it exits 
the drain hole (during ground time). KLM also stated that the costs, 
manpower, and additional downtime associated with the actions in the 
NPRM are too high for KLM, and it is not convinced the actions will 
contribute to any additional safety.
    We infer the commenter wants the NPRM (76 FR 34625, June 14, 2011) 
withdrawn. We disagree. The NPRM

[[Page 16144]]

addresses drain holes of the wing leading edge that are located close 
to the engine nozzle such that a fuel leak from any cause, not just 
from a slat housing leak, is drained directly on the engine exhaust 
nozzle, which could cause a fuel fire. Therefore, we consider that a 
risk for a fire exists even on the airplane models that do not have the 
slat cans. We also disagree with the commenter that the modification 
does not provide an improvement to the fuel drainage system. The 
service information provides instructions to modify and redirect the 
leading edge drainage away from the drain hole that directly impinges 
on the engine exhaust nozzle, which reduces the risk of a fire during a 
fuel leak event. We have taken the cost of labor and parts into 
consideration and have found that the actions required by this final 
rule are needed to address the unsafe condition. We have not changed 
the final rule in this regard.

Request To Include Service Information Revision

    Boeing requested the NPRM (76 FR 34625, June 14, 2011) include 
Boeing Special Attention Service Bulletin 747-57-2332, Revision 1, 
dated July 25, 2011, as an option to Boeing Special Attention Service 
Bulletin 747-57-2332, dated November 9, 2010 (which was referenced in 
the proposed AD as the appropriate source of service information for 
the modification). Boeing justified its request by stating that 
Revision 1 of this service information adds clarification, but has no 
new requirements.
    We agree. Since the NPRM (76 FR 34625, June 14, 2011) was issued, 
Boeing has issued Boeing Special Attention Service Bulletin 747-57-
2332, Revision 1, dated July 25, 2011, which clarifies certain 
information and provides optional materials. We have changed paragraphs 
(c) and (g) of this AD to refer to Boeing Special Attention Service 
Bulletin 747-57-2332, Revision 1, dated July 25, 2011; added paragraph 
(h) of the AD to give credit for actions already accomplished in 
accordance with Boeing Special Attention Service Bulletin 747-57-2332, 
dated November 9, 2010; and revised subsequent paragraph lettering.

Request To Delegate Approval of Structures-Related Alternative Methods 
of Compliance (AMOCs)

    Boeing requested the final rule be changed to allow Boeing 
authority to approve AMOCs under Boeing Commercial Airplanes 
Organization Designation Authorization (ODA). Boeing stated it 
anticipates repairs will be required to panels and ribs, etc., and that 
when the service information is embodied, it would be beneficial if the 
Boeing ODA was authorized to approve these repairs.
    We agree with the request to delegate structural AMOC approval to 
the Boeing ODA because using the Boeing ODA is an appropriate process 
for making those findings. Accordingly, we have added paragraph (i)(3) 
to this final rule.

Additional Change Made to This Final Rule

    We have revised the heading and marking of paragraph (h) of this 
AD. This change has not changed the intent of the paragraph.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
the AD with the changes described previously and minor editorial 
changes. We have determined that these minor changes:
    <bullet> [Agr]re consistent with the intent that was proposed in 
the NPRM (76 FR 34625, June 14, 2011) for correcting the unsafe 
condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM (76 FR 34625, June 14, 2011).
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of the AD.

 Costs of Compliance

    We estimate that this AD affects 258 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
               Action                         Labor cost            Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Fluid drainage modification (Groups  95 work-hours x $85 per             $33,609         $41,684      $5,960,812
 1-6) (143 airplanes).                hour = $8,075.
Fluid drainage modification (Groups  90 work-hours x $85 per              29,304          36,954       4,249,710
 7-10) (115 airplanes).               hour = $7,650.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this AD may be 
covered under warranty, thereby reducing the cost impact on affected 
individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities

[[Page 16145]]

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):

2012-05-03 The Boeing Company: Amendment 39-16975; Docket No. FAA-
2011-0566; Directorate Identifier 2010-NM-271-AD.

(a) Effective Date

    This AD is effective April 24, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to 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, as identified in Boeing Special Attention Service 
Bulletin 747-57-2332, Revision 1, dated July 25, 2011.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by a design review following a ground fire 
incident and reports of flammable fluid leaks from the wing leading 
edge area onto the engine exhaust area. We are issuing this AD to 
prevent flammable fluid from leaking onto the engine exhaust nozzle, 
which could result in a fire.

(f) Compliance

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

(g) Leading Edge Installation

    Within 60 months after the effective date of this AD, modify the 
fluid drain path in the leading edge area of the wing, in accordance 
with the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 747-57-2332, Revision 1, dated July 25, 2011.

(h) Credit for Previous Actions

    This paragraph provides credit for modifications of the fluid 
drain path required by paragraph (g) of this AD, if the modification 
was performed before the effective date of this AD, using Boeing 
Special Attention Service Bulletin 747-57-2332, dated November 9, 
2010.

(i) Alternative Methods of Compliance (AMOCs)

    (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. 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 ACO, send it to the 
attention of the person identified in the Related Information 
section 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 structural repairs required by this AD if it is approved by 
the Boeing Commercial Airplanes Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Seattle 
ACO to make those findings. For a repair method to be approved, the 
repair must meet the certification basis of the airplane and the 
approval must specifically refer to this AD.

(j) Related Information

    For more information about this AD, contact Tung Tran, Aerospace 
Engineer, Propulsion Branch, ANM-140S, Seattle Aircraft 
Certification Office (ACO), FAA, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; phone: 425-917-6505; fax: 425-917-6590; 
email: [email protected].

(k) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) of the following under 5 U.S.C. 552(a) and 1 CFR 
part 51:
    (i) Boeing Special Attention Service Bulletin 747-57-2332, 
Revision 1, dated July 25, 2011.
    (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; phone: 206-
544-5000, extension 1; fax: 206-766-5680; email: 
[email protected]; Internet: https://www.myboeingfleet.com.
    (3) You may review copies of the referenced 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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on February 27, 2012.
Jeffrey E. Duven,
Acting Manager. Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-6116 Filed 3-19-12; 8:45 am]
BILLING CODE 4910-13-P


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