AD 2013-04-11
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 737-600 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-700 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-800 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-900ER Series | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Incorrect wire support clamps installed within the left environmental control systems (ECS) bay could allow wiring to come in contact with the exposed metal of the improper clamp, potentially leading to electrical arcing and a potential ignition source within the ECS bay.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect to identify the part number of the wire support clamp. Investigate and take corrective actions if necessary, including replacing the discrepant clamp with a new or serviceable TA0930034-10, TA0930034-10P, TA0930034-11, or TA0930034-12P wire support clamp if the part number is incorrect. Repair or replace chafed wiring as needed.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 737-600, -700, -800, and -900ER series airplanes.
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 certain The Boeing Company Model 737-600, -700, -800, and -900ER series airplanes. This AD was prompted by incorrect wire support clamps installed within the left environmental control systems (ECS) bay, which could allow wiring to come in contact with the exposed metal of the improper clamp. This AD requires inspections to identify the part number of the wire support clamp, related investigative actions, and corrective actions if necessary. We are issuing this AD to prevent electrical arcing and a potential ignition source within the ECS bay, which in combination with flammable fuel vapors, could result in a center wing fuel tank explosion, and consequent loss of the airplane.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to The Boeing Company Model 737-600, -700, -800,
and -900ER series airplanes, certificated in any category,
identified in Boeing Special Attention Service Bulletin 737-28-1303,
dated April 26, 2012.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 78, Number 45 (Thursday, March 7, 2013)]
[Rules and Regulations]
[Pages 14644-14647]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2013-04633]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0860; Directorate Identifier 2012-NM-123-AD;
Amendment 39-17369; AD 2013-04-11]
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 737-600, -700, -800, and -900ER series
airplanes. This AD was prompted by incorrect wire support clamps
installed within the left environmental control systems (ECS) bay,
which could allow wiring to come in contact with the exposed metal of
the improper clamp. This AD requires inspections to identify the part
number of the wire support clamp, related investigative actions, and
corrective actions if necessary. We are issuing this AD to prevent
electrical arcing and a potential ignition source within the ECS bay,
which in combination with flammable fuel vapors, could result in a
center wing fuel tank explosion, and consequent loss of the airplane.
DATES: This AD is effective April 11, 2013.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of April 11,
2013.
ADDRESSES: For service information identified in this AD, contact
Boeing
[[Page 14645]]
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; Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
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 <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 (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: Georgios Roussos, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356;
phone: 425-917-6482; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#e582808a97828c8a96cb978a9096968a96a5838484cb828a93"><span class="__cf_email__" data-cfemail="7512101a07121c1a065b071a0006061a06351314145b121a03">[email protected]</span></a>.
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 August 27, 2012 (77 FR
51720). That NPRM proposed to require inspections to identify the part
number (P/N) of the wire support clamp, related investigative actions,
and corrective actions if necessary.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
(77 FR 51720, August 27, 2012) and the FAA's response to each comment.
Statement To Address Effects of NPRM (77 FR 51720, August 27, 2012) on
Winglets
Aviation Partners Boeing stated that the installation of winglets
per Supplemental Type Certificate (STC) ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight=st00830se">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight=st00830se</a>) does
not affect the actions specified by the NPRM (77 FR 51720, August 27,
2012).
Requests To Remove or Change the ``Parts Installation Prohibition''
Section
Boeing requested the ``Parts Installation Prohibition,'' paragraph
(h) of the NPRM (77 FR 51720, August 27, 2012), be removed because
there are other types of clamps installed within the ECS bay that are
not included in either Boeing Special Attention Service Bulletin 737-
28-1303, dated April 26, 2012, or the NPRM (77 FR 51720, August 27,
2012). Boeing also requested that we include P/Ns TA0930034-10P,
TA0930034-11, and TA0930034-12P wire support clamps because they are
interchangeable with P/N TA0930034-10. Alaska Airlines requested that
the ``Parts Installation Prohibition'' paragraph be changed to clarify
affected airplanes, and pointed out that AD 2010-24-11, Amendment 39-
16530 (75 FR 74616, December 1, 2010), also addresses clamps installed
in the left ECS bay, but allows installation of clamp P/N TA0930034-11
at the same clamp position. Delta Air Lines (Delta) requested that we
ensure that paragraph (h) of the NPRM, only applies to those airplanes
subject to the NPRM. Japan Airlines requested that we specify, in
paragraph (h) of the NPRM, the locations within the left ECS bay that
P/N TA0930034-10P clamps may be installed.
We agree to revise paragraph (i) of this AD (referred to as
paragraph (h) in the NPRM (77 FR 51720, August 27, 2012)). We agree to
allow installation of wire support clamps P/Ns TA0930034-10P,
TA0930034-11, and TA0930034-12P, in addition to P/N TA0930034-10, and
to limit the prohibition to the locations specified in Figures 1
through 4 of Boeing Special Attention Service Bulletin 737-28-1303,
dated April 26, 2012. We have revised paragraph (i) of this AD
accordingly.
In addition, we agree to clarify the phrase ``on any airplane''
used in paragraph (i) of this AD. The applicability statement in all AD
actions lists all airplanes affected by that AD. All of the
requirements stated in an AD are applicable only to the airplanes
listed in the applicability of that AD. We have not changed the final
rule regarding this issue.
Requests To Allow Use of Certain Other Wire Support Clamps
Boeing and Japan Airlines requested that the NPRM (77 FR 51720,
August 27, 2012) allow use of certain other wire support clamps in
addition to P/N TA0930034-10, as specified by Boeing Special Attention
Service Bulletin 737-28-1303, dated April 26, 2012. Japan Airlines
requested that we allow the use of clamp P/N TA0930034-10P, and
referred to discussions with Boeing that support use of this part
number clamp, that is also fully cushioned. Boeing requested the
corrective actions statement in the ``Relevant Service Information''
section of the preamble of the NPRM (77 FR 51720, August 27, 2012) be
revised to read, ``Corrective actions include replacing the discrepant
clamp with a new or serviceable TA0930034-10, TA0930034-10P, TA0930034-
11, or TA0930034-12P wire support clamp if the part number is
incorrect, and repairing or replacing chafed wiring.'' Boeing stated
that P/Ns TA0930034-10P, TA0930034-11, and TA0930034-12P are
interchangeable with P/N TA0930034-10.
We agree to allow installation of P/Ns TA0930034-10P, TA0930034-11,
and TA0930034-12P wire support clamps. We have added new paragraph (h)
in this final rule to provide an exception to Boeing Special Attention
Service Bulletin 737-28-1303, dated April 26, 2012, allow use of P/Ns
TA0930034-10P, TA0930034-11, and TA0930034-12P wire support clamps. We
have re-identified subsequent paragraphs accordingly.
We partially agree with the intent of Boeing's request to revise
the ``Relevant Service Information'' section of the NPRM (77 FR 51720,
August 27, 2012). Boeing's request included removing the phrase ``or if
the flange cushions do not completely surround the two metal strap
sections of the wire support clamp.'' This phrase is based on the
procedures specified in Step 1 of Figures 1 and 2 of Boeing Special
Attention Service Bulletin 737-28-1303, dated April 26, 2012, and is
part of the inspection required by this AD. Therefore, we do not agree
that this phrase should be removed from the description of the
inspection. As stated previously, we do agree that installing P/Ns
TA0930034-10P, TA0930034-11, and TA0930034-12P wire support clamps is
acceptable for accomplishing the corrective action. However, the
``Relevant Service Information'' section of the NPRM is not restated in
this AD, so we have not revised this AD in this regard.
[[Page 14646]]
Request To Clarify Impacted Fuel Tank
Boeing requested that the ``Summary'' and ``Discussion'' sections
in the NPRM (77 FR 51720, August 27, 2012) be revised to add the text,
``in the center wing tank,'' and to read, ``We are proposing this AD to
prevent electrical arcing and a potential ignition source in the center
wing tank, which in combination with flammable fuel vapors could result
in a fuel tank explosion, and consequent loss of the airplane,'' to
clarify the area that might be potentially impacted by the unsafe
condition identified in the NPRM.
We partially agree. We agree with Boeing's request to identify the
center wing tank as the impacted tank, because the center wing tank
located above the ECS bay is the fuel tank potentially affected by the
unsafe condition identified in this AD. We disagree to state that this
AD will prevent electrical arcing and a potential ignition source in
the center wing tank, because the potential ignition source has been
identified to be within the ECS bay, which is a flammable leakage fluid
zone. A potential ignition within the ECS bay could lead to a fire in
the area and potentially result in a center wing tank explosion.
Therefore, we agree to identify the center wing tank as the affected
fuel tank without including the misleading statement that this AD will
prevent electrical arcing within the fuel tank. We further recognize
that the same issue applies to paragraph (e), ``Unsafe Condition,'' of
this AD and note that the ``Discussion'' section that appeared in the
NPRM (77 FR 51720, August 27, 2012) is not restated in the final rule.
We have revised the Summary and paragraph (e) of this AD to specify
that we are issuing this AD ``to prevent electrical arcing and a
potential ignition source within the ECS bay, which in combination with
flammable fuel vapors, could result in a center wing fuel tank
explosion, and consequent loss of the airplane.''
Request To Clarify Airplane Maintenance Data
Delta pointed to inconsistencies between the type design data and
the aircraft illustrated parts catalog (AIPC) used for maintaining
airplanes. Delta stated that the AIPC does not accurately identify all
clamp locations that are needed for AD compliance, and pointed out that
discrepancies within type design data and maintenance data could result
in a re-occurrence of clamp installation discrepancies, which occurred
in production and resulted in the airworthiness directive.
We acknowledge that if operators refer to and use an inaccurate
AIPC, it could result in non-compliance with AD requirements. However,
it is the responsibility of the operators to ensure that they are in
compliance with AD requirements. In addition, the AIPC is not an FAA
approved or controlled document. We have not changed the AD in this
regard.
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> Are consistent with the intent that was proposed in the
NPRM (77 FR 51720, August 27, 2012) for correcting the unsafe
condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM (77 FR 51720, August 27, 2012).
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 297 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
Estimated costs
----------------------------------------------------------------------------------------------------------------
Cost per Number of Cost on U.S.
Action Labor cost Parts cost product airplanes operators
----------------------------------------------------------------------------------------------------------------
Inspection Group 1 airplanes.. 10 work-hours x $0 $850 185 $157,250
$85 per hour =
$850.
Inspection Group 2 airplanes.. 2 work-hours x 0 170 112 19,040
$85 per hour =
$170.
----------------------------------------------------------------------------------------------------------------
We estimate the following costs to do any necessary replacements
that would be required based on the results of the required inspection.
We have no way of determining the number of aircraft that might need
these replacements.
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
Replacement of wire support clamp............ 1 work-hour x $85 per hour = $3 $88
$85.
----------------------------------------------------------------------------------------------------------------
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.
We have received no definitive data that would enable us to provide
cost estimates for the on-condition repair of chafed or damaged wiring
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.
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
[[Page 14647]]
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 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):
2013-04-11 The Boeing Company: Amendment 39-17369; Docket No. FAA-
2012-0860; Directorate Identifier 2012-NM-123-AD.
(a) Effective Date
This AD is effective April 11, 2013.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 737-600, -700, -800,
and -900ER series airplanes, certificated in any category,
identified in Boeing Special Attention Service Bulletin 737-28-1303,
dated April 26, 2012.
(d) Subject
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 28, Fuel System.
(e) Unsafe Condition
This AD was prompted by incorrect wire support clamps installed
within the left environmental control systems (ECS) bay, which could
allow wiring to come in contact with the exposed metal of the
improper clamp. We are issuing this AD to prevent electrical arcing
and a potential ignition source within the ESC bay, which in
combination with flammable fuel vapors, could result in a center
wing fuel tank explosion, and consequent loss of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Inspection and Corrective Actions
Within 60 months after the effective date of this AD, do a
detailed inspection for part number (P/N) TA0930034-10 wire support
clamp at the locations specified in Figures 1 through 4 of Boeing
Special Attention Service Bulletin 737-28-1303, dated April 26,
2012, and do all applicable related investigative and corrective
actions, in accordance with the Accomplishment Instructions of
Boeing Special Attention Service Bulletin 737-28-1303, dated April
26, 2012, except as provided by paragraph (h) of this AD. Do all
applicable related investigative and corrective actions before
further flight.
(h) Exception to Service Information
Where Boeing Special Attention Service Bulletin 737-28-1303,
dated April 26, 2012, specifies to install P/N TA0930034-10 wire
support clamp, this AD also allows installation of P/Ns TA0930034-
10P, TA0930034-11, and TA0930034-12P wire support clamps.
(i) Parts Installation Prohibition
As of the effective date of this AD, no person may install a
wire support clamp at the locations specified in Figures 1 through 4
of Boeing Special Attention Service Bulletin 737-28-1303, dated
April 26, 2012, on any airplane, unless the wire support clamp is P/
N TA0930034-10, TA0930034-10P, TA0930034-11, or TA0930034-12P.
(j) 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: <a href="/cdn-cgi/l/email-protection#80b9adc1cecdadd3e5e1f4f4ece5adc1c3cfadc1cdcfc3add2e5f1f5e5f3f4f3c0e6e1e1aee7eff6"><span class="__cf_email__" data-cfemail="a59c88e4ebe888f6c0c4d1d1c9c088e4e6ea88e4e8eae688f7c0d4d0c0d6d1d6e5c3c4c48bc2cad3">[email protected]</span></a>.
(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.
(k) Related Information
For more information about this AD, contact Georgios Roussos,
Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA,
Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton,
WA 98057-3356; phone: 425-917-6482; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#492e2c263b2e20263a673b263c3a3a263a092f2828672e263f"><span class="__cf_email__" data-cfemail="9afdfff5e8fdf3f5e9b4e8f5efe9e9f5e9dafcfbfbb4fdf5ec">[email protected]</span></a>.
(l) 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 737-28-1303, dated
April 26, 2012.
(ii) Reserved.
(3) 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; Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(4) You may view this service information at 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.
(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, call 202-741-6030, or go to: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on February 20, 2013.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2013-04633 Filed 3-6-13; 8:45 am]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
Related Airworthiness Directives
2025-25-04
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: inflation of the escape slide while it is in the escape slide compartment, which could result in injury to passengers and crew during normal operation, or impede an emergency evacuation by renderin...
2025-19-12
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: Improper grinding of the inner diameter of the main landing gear (MLG) outer cylinders, resulting in possible heat damage to the outer cylinders. This could cause failure of a principal structural ...
2025-15-01 Recurring
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: A frame web crack at a certain fuselage station (STA) between certain stringers common to the frame web notch.
2025-07-03 Recurring
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: cracking in the station (STA) 663.75 frame fitting outboard chords and failsafe straps adjacent to the stringer S-18A straps, which could result in failure of a principal structural element (PSE) t...
