[Federal Register Volume 71, Number 161 (Monday, August 21, 2006)]
[Proposed Rules]
[Pages 48493-48495]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-13730]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25642; Directorate Identifier 2006-NM-121-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 757 Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Boeing Model 757 airplanes. This proposed AD would require 
inspecting certain power feeder wire bundles for damage, inspecting the 
support clamps for these wire bundles to determine whether the clamps 
are properly installed, and performing corrective actions if necessary. 
This proposed AD results from a report that a power feeder wire bundle 
chafed against the number six auxiliary slat track, causing electrical 
wires in the bundle to arc, which damaged both the auxiliary slat track 
and power feeder wires. We are proposing this AD to prevent arcing that 
could be a possible ignition source for leaked flammable fluids, which 
could result in a fire. Arcing could also result in a loss of power 
from the generator connected to the power feeder wire bundle, and 
consequent loss of systems, which could reduce controllability of the 
airplane.

DATES: We must receive comments on this proposed AD by October 5, 2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401, 
Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for the service information identified in this 
proposed AD.

FOR FURTHER INFORMATION CONTACT: Philip Sheridan, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6441; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``FAA-2006-
25642; Directorate Identifier 2006-NM-121-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may examine the 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 DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the Docket Management System 
receives them.

Discussion

    We have received a report indicating that a power feeder wire 
bundle chafed against the number six auxiliary slat track at front spar 
station (FSS) 148.90 on a Boeing Model 757 airplane. Two of the three 
phases of the power feeder wire bundle were worn to the conductor. The 
chafing caused electrical wires in the bundle to arc, which damaged 
both the auxiliary slat track and power feeder wires. Investigation 
revealed that the support clamp for the power feeder wire bundle was 
not properly installed in the attach bracket, which resulted in 
insufficient clearance between the power feeder wire bundle and the 
auxiliary slat track. Arcing of the electrical wires in the power 
feeder wire bundle could be a possible ignition source for leaked 
flammable fluids, which could result in a fire. Arcing could also 
result in a loss of power from the generator connected to the power 
feeder wire bundle, and consequent loss of systems which could reduce 
controllability of the airplane.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletins 757-24-
0105 and 757-24-0106, both Revision 2, both dated April 20, 2006. The 
service bulletins describe procedures for inspecting for damage 
(including but not limited to chafing) of power feeder wire bundles 
W3312 and W3412 at FSS 148.90 in the left and right wings; inspecting 
support clamps for these wire bundles to determine whether the clamps 
are properly installed in the attach bracket; and performing corrective 
actions if necessary.
    For airplanes identified as Group 1 in Special Attention Service 
Bulletin 757-24-0105, proper installation in the left wing consists of 
the support clamp being installed in the upper hole of the lower attach 
bracket, with the lobe of the support clamp installed in the ``up'' 
position. Proper installation in the right wing on Group 1 airplanes 
consists of the support clamp being installed in the lower hole of the 
support bracket. For airplanes other than those in Group 1, proper 
installation on both wings consists of the support clamp being 
installed in the lower hole of the attach bracket.
    Corrective actions are as follows:
     Repairing any damage of the power feeder wire bundles.
     Installing in the correct hole of the attach bracket any 
support clamp found installed elsewhere, and installing a spacer if one 
is not already installed.

[[Page 48494]]

     Installing a rivet to plug the open hole in the attach 
bracket.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other airplanes 
of this same type design. For this reason, we are proposing this AD, 
which would require accomplishing the actions specified in the service 
information described previously.

Clarification of Inspection Terminology

    The service bulletins include the instruction to inspect the wire 
bundles and support clamps, but the Work Instructions do not 
specifically state what type of inspection is necessary. However, the 
term ``general visual inspection'' is defined under paragraph 3.A., 
General Information, in the Accomplishment Instructions of the service 
bulletins. Thus, this proposed AD refers to these inspections as 
``general visual inspections.''

Costs of Compliance

    There are about 902 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 631 airplanes of 
U.S. registry. The proposed actions would take about 2 work hours per 
airplane, at an average labor rate of $80 per work hour. Based on these 
figures, the estimated cost of the proposed AD for U.S. operators is 
$100,960, or $160 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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 the proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the 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 proposed 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, Safety.

The Proposed Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

    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]

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

Boeing: Docket No. FAA-2006-25642; Directorate Identifier 2006-NM-
121-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by October 
5, 2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 757-200, -200PF, -200CB, and 
-300 series airplanes; certificated in any category; as identified 
in the service bulletins listed in Table 1 of this AD.

                                             Table 1.--Applicability
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                                          Boeing Special Attention     Revision
            Airplane model                    Service Bulletin           level                 Date
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757-200, -200PF, -200CB series........                   757-24-0105           2  April 20, 2006.
757-300 series........................                   757-24-0106           2  April 20, 2006.
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Unsafe Condition

    (d) This AD results from a report that a power feeder wire 
bundle chafed against the number six auxiliary slat track, causing 
electrical wires in the bundle to arc, which damaged both the 
auxiliary slat track and power feeder wires. We are issuing this AD 
to prevent arcing that could be a possible ignition source for 
leaked flammable fluids, which could result in a fire. Arcing could 
also result in a loss of power from the generator connected to the 
power feeder wire bundle, and consequent loss of systems, which 
could reduce controllability of the airplane.

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.

Service Bulletin Reference

    (f) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of the following service bulletins, as 
applicable:
    (1) For Model 757-200, -200PF, and -200CB series airplanes: 
Boeing Special Attention Service Bulletin 757-24-0105, Revision 2, 
dated April 20, 2006; and
    (2) For Model 757-300 series airplanes: Boeing Special Attention 
Service Bulletin 757-24-0106, Revision 2, dated April 20, 2006.

One-Time Inspections and Corrective Actions

    (g) Within 24 months after the effective date of this AD, 
perform a general visual inspection for damage (including but not 
limited to chafing) of power feeder wire

[[Page 48495]]

bundles W3312 and W3412 at front spar station 148.90 in the left and 
right wings, and a general visual inspection of the support clamps 
for those power feeder wire bundles to determine whether the clamps 
are properly installed, and, before further flight, do all 
applicable corrective actions. Do these actions by doing all of the 
applicable actions in the service bulletin.

Actions Accomplished Previously

    (h) Inspections and corrective actions done before the effective 
date of this AD in accordance with the service information listed in 
Table 2 of this AD are acceptable for compliance with the 
corresponding actions required by this AD.

                              Table 2.--Other Acceptable Service Bulletin Revisions
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Boeing Special Attention Service Bulletin         Revision level                           Date
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757-24-0105..............................  Original....................  September 30, 2004.
757-24-0105..............................  1...........................  June 23, 2005.
757-24-0106..............................  Original....................  September 30, 2004.
757-24-0106..............................  1...........................  June 23, 2005.
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Special Flight Permit

    (i) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished, provided that the 
generator served by the power feeder wire bundles specified in 
paragraph (g) of this AD is disconnected.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
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 Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

    Issued in Renton, Washington, on August 11, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-13730 Filed 8-18-06; 8:45 am]
BILLING CODE 4910-13-P