[Federal Register Volume 71, Number 112 (Monday, June 12, 2006)]
[Rules and Regulations]
[Pages 33611-33614]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-5205]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-20626; Directorate Identifier 2004-NM-243-AD; 
Amendment 39-14636; AD 2006-12-11]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-600, -700, -700C, -
800, and -900 Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Boeing Model 737-600, -700, -700C, -800, and -900 series 
airplanes. This AD requires replacing the fuel shutoff valve wires and 
conduit assemblies in the left and right engine strut aft fairing 
areas. This AD results from a report that an operator discovered many 
small chafe marks and exposed shield braid on fuel shutoff wires routed 
through a conduit in the wing. We are issuing this AD to prevent 
exposed wires that could provide an ignition source in a flammable 
leakage zone and possibly lead to an uncontrolled fire or explosion.

DATES: This AD becomes effective July 17, 2006.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of July 17, 
2006.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., Nassif Building, 
Room PL-401, Washington, DC.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT: Doug Pegors, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 917-6504; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Examining the Docket

    You may examine the airworthiness directive (AD) docket on the 
Internet at http://dms.dot.gov or in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the street address stated in the ADDRESSES section.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to certain Boeing Model 
737-600, -700, -700C, -800, and -900 series airplanes. That NPRM was 
published in the Federal Register on March 16, 2005 (70 FR 12815). That 
NPRM proposed to require replacing the fuel shutoff valve wires and 
conduit assemblies in the left and right engine strut aft fairing 
areas.

Explanation of Revised Service Information

    Since we issued the NPRM, Boeing revised Special Attention Service 
Bulletin 737-28-1199, dated September 9, 2004, which was specified in 
the NPRM as the appropriate source of service information for 
accomplishing the proposed requirements of this AD. We have reviewed 
Boeing Special Attention Service Bulletin 737-28-1199, Revision 1, 
dated December 15, 2005. Service Bulletin 737-28-1199, Revision 1, 
incorporates information specified in Boeing Information Notice (IN) 
737-28-1199 IN 01, dated November 4, 2004, and additional similar 
changes' although the procedures remain essentially the same. The 
information and similar changes include revisions to certain part 
numbers and materials; changes to the step tables and notes in several 
figures; addition of drawings used in the preparation of the service 
bulletin; deletion of the reference to Appendix A of the service 
bulletin; clarification of work instructions; and other changes. 
Accomplishing the actions specified in the service information is 
intended to

[[Page 33612]]

adequately address the unsafe condition.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Support for the AD

    Two commenters, the Airline Pilots Association (ALPA), and AirTran 
Airways, support the proposed AD.

Request To Extend Compliance Time

    Four commenters, Continental, KLM Royal Dutch Airlines (KLM), 
American Airlines, and the Air Transport Association (ATA) on behalf of 
American Airlines, request that the compliance time of 24 months 
specified by the NPRM be extended to 36 months or longer. American 
Airlines requests that the compliance time be extended to 72 months. 
The commenters contend that the amount of work proposed by the NPRM 
will not be possible to accomplish within 24 months without 
considerable extra maintenance activity at great expense and hardship. 
The commenters assert that revising the compliance time as requested 
will bring the AD into closer alignment with scheduled heavy 
maintenance checks and greatly ease this burden.
    We agree that an extension of the compliance time could allow 
closer alignment with scheduled maintenance for some operators; 
however, extending the compliance time to 72 months would expose the 
fleet to an unacceptable level of increased risk. We have determined 
that extending the 24-month compliance time by 12 months will bring 
this AD into closer alignment with scheduled maintenance without an 
unacceptable increase in risk to the fleet. Accordingly, we have 
revised paragraph (f) of the AD to specify a compliance time of 36 
months. Further, to obtain even longer compliance times, anyone may 
request approval of an AMOC as specified in paragraph (h) of this AD, 
provided data are submitted to demonstrate that an acceptable level of 
safety will be maintained.

Request for Wiring Diagram Manual Update

    One commenter, Continental, requests that Boeing either incorporate 
the revised wiring configuration specified by the service bulletin into 
the existing wiring diagram manual or issue a new manual. Continental 
asserts that a maintenance technician could unintentionally undo the 
wire configuration specified by the AD if the existing wiring diagram 
manual is used after this AD has been performed. Continental states 
that a revised wiring diagram manual is necessary to maintain the wire 
routing and modification configuration required by this AD.
    We agree that it is essential to maintain proper modification 
configuration. Section K of Service Bulletin 737-28-1199, Revision 1, 
lists all publications affected by changes to the service bulletin, 
such as the wiring diagram manual and illustrated parts catalog. These 
manuals provide all information needed for maintenance personnel to 
maintain the wiring configuration detailed by the AD; therefore, such 
manuals must be current. To ensure this, the release of a service 
bulletin triggers an update of these manuals. We have confirmed with 
Boeing that all documents referenced in section K of any Boeing service 
bulletin are updated and available to operators at the time that 
service bulletin is released; but that it remains the operator's 
responsibility to ensure that the updated documents are incorporated 
into the operator's manuals. No change is needed to the AD in this 
regard.

Request To Identify Wire Bundle

    One commenter, Continental, requests that we revise the NPRM to 
require installing red-colored identification sleeves on the engine 
fuel shutoff valve wire bundle. Continental contends that such sleeves, 
labeled ``CAUTION'' (followed with the service bulletin number ``737-
28-1199'' or the operator's number), should be installed on the wire 
bundle at intervals of 12 to 24 inches. Continental states that similar 
red identification sleeves are installed on the 737 CL (Classic) 
Isolated Fuel Quantity Transmitter (IFQT) wiring.
    We do not agree. Identification of the IFQT safe side wiring is 
necessary to maintain isolation of those wires from other high-power 
wiring that may be routed in close proximity. However, isolation of the 
engine fuel shutoff valve wire bundle is not a safety-critical issue. 
No change is needed to the AD in this regard.

Request To Reissue Service Bulletin

    One commenter, Continental, requests that the service bulletin be 
reissued with a clearer description of the unsafe condition. 
Continental requests certain language in the service bulletin be 
changed to read, ``The exposure of the wire shield braid could cause 
electrical arcing in the fuel leakage zone, which could result in an 
uncontrolled fire and explosion as well as an in-flight engine 
shutdown.'' Continental asserts that this language clarifies the 
urgency of the unsafe condition and that the service bulletin should 
therefore be reissued as an alert service bulletin.
    We agree that it is desirable to reflect unsafe conditions in 
service information as clearly as possible, as this would add a sense 
of urgency to the service information. However, we have revised the AD 
to refer to Boeing Service Bulletin 737-28-1199, Revision 1, as the 
appropriate source of service information for accomplishing the 
required actions of the AD (refer to ``Explanation of Changes Made to 
This AD''). Revision 1 refers to the possibility of engine shutdown and 
we have determined that adding ``alert'' to the title of the service 
bulletin will have no effect upon airplane safety. No change is needed 
to the AD in this regard.

Request To Revise Costs of Compliance

    Two commenters, Continental and ATA, on behalf of its member, 
American Airlines, state that the Costs of Compliance shown in the NPRM 
do not correspond with labor estimates provided by the service 
bulletin. American Airlines states that the service bulletin specifies 
77 work hours rather than the 42 work hours estimated by the NPRM, 
while Continental asserts that the correct figure should be 50 work 
hours. Though no request was made, we infer that the commenters wish us 
to increase the number of work hours shown in the Costs of Compliance.
    We do not agree with this request. Based on the best data 
available, the manufacturer provided the number of work hours necessary 
to do the required actions. This number represents the time necessary 
to perform only the actions actually required by this AD. We recognize 
that in doing the actions required by an AD, operators may incur 
incidental costs in addition to the direct costs. The cost analysis in 
AD rulemaking actions, however, typically does not include incidental 
costs such as the time required to gain access and to close up, time 
necessary for planning, or time necessitated by other administrative 
actions. While the service bulletin includes an estimate of the cost to 
access and close up the aft fairing areas of the engine struts in order 
to perform the required fuel shutoff valve wire and conduit assembly 
replacements, we do not include those costs in our estimate. We have 
not changed the AD in this regard; however, we have provided some 
relief to operators by extending the compliance time, as described 
earlier.

[[Page 33613]]

Explanation of Changes Made to This AD

    Service Bulletin 737-28-1199, Revision 1, Paragraph 1.A.--
Effectivity, shows changes of airplane operators from the original 
issue of the service bulletin. Therefore, we have revised paragraph (c) 
of the AD to refer to Service Bulletin 737-28-1199, Revision 1, to 
determine the applicability of the AD. No new airplanes have been 
added.
    We have revised this action to clarify the appropriate procedure 
for notifying the principal inspector before using any approved AMOC on 
any airplane to which the AMOC applies.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are about 1,338 airplanes of the affected design in the 
worldwide fleet. This AD will affect about 529 airplanes of U.S. 
registry. The required actions will take about 42 work hours per 
airplane, at an average labor rate of $65 per work hour. Required parts 
will cost about $2,418 per airplane. Based on these figures, the 
estimated cost of the AD for U.S. operators is $2,723,292, or $5,148 
per airplane.

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

    We have determined that 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket. See the ADDRESSES 
section for a location to examine the regulatory evaluation.

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.


Sec.  39.13  [Amended]

0
2. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

2006-12-11 Boeing: Amendment 39-14636. Docket No. FAA-2005-20626; 
Directorate Identifier 2004-NM-243-AD.

Effective Date

    (a) This AD becomes effective July 17, 2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-600, -700, -700C, -800, 
and -900 series airplanes; certificated in any category; as listed 
in Boeing Special Attention Service Bulletin 737-28-1199, Revision 
1, dated December 15, 2005.

Unsafe Condition

    (d) This AD was prompted by a report that an operator discovered 
many small chafe marks and exposed shield braid on fuel shutoff 
valve wires routed through a conduit in the wing. We are issuing 
this AD to prevent exposed wires that could provide an ignition 
source in a flammable leakage zone and possibly lead to an 
uncontrolled fire or explosion.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Parts Replacement

    (f) Within 36 months after the effective date of this AD, 
replace the fuel shutoff valve wires and conduit assemblies in the 
left and right engine strut aft fairing areas with new fuel shutoff 
valve wires and conduit assemblies, by accomplishing all the actions 
in accordance with the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 737-28-1199, Revision 1, dated December 
15, 2005.

Actions Accomplished Using Prior Version of Service Information

    (g) Actions accomplished before the effective date of this AD in 
accordance with Special Attention Service Bulletin 737-28-1199, 
dated September 9, 2004, are considered acceptable for compliance 
with the applicable action specified in this AD.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with 14 CFR 
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Material Incorporated by Reference

    (i) You must use Boeing Special Attention Service Bulletin 737-
28-1199, Revision 1, dated December 15, 2005, to perform the actions 
that are required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference of this document in accordance with 5 U.S.C. 552(a) and 1 
CFR part 51. Contact Boeing Commercial Airplanes, P.O. Box 3707, 
Seattle, Washington 98124-2207, for a copy of this service 
information. You may review copies at the Docket Management 
Facility, U.S. Department of Transportation, 400 Seventh Street SW., 
Room PL-401, Nassif Building, Washington, DC; on the Internet at 
http://dms.dot.gov; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.


[[Page 33614]]


    Issued in Renton, Washington, on May 31, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 06-5205 Filed 6-9-06; 8:45 am]
BILLING CODE 4910-13-P