[Federal Register Volume 65, Number 181 (Monday, September 18, 2000)]
[Proposed Rules]
[Pages 56264-56266]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-23853]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-19-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767 Series Airplanes 
Powered by Pratt & Whitney Model PW4000 Series Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Boeing Model 767 series 
airplanes. This proposal would require a one-time detailed visual 
inspection of certain wire bundles located in the aft section of the 
strut forward fairing panel of both engine struts to detect chafing 
damage, and repair or replacement of wiring, if necessary. This action 
is necessary to prevent the potential for dual wire faults from 
grounded, separated, or shorted wires; which could result in 
inadvertent takeoff thrust overboost, in-flight loss of thrust, or 
engine shutdown.

DATES: Comments must be received by November 2, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-19-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-19-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Dennis Kammers, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 227-2956; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule.
    The proposals contained in this notice may be changed in light of 
the comments received.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-19-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 2000-NM-19-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating several incidents of severe 
chafing of certain wire bundles in both engine struts on Model 767 
series airplanes powered by Pratt & Whitney PW4000 series engines. One 
incident resulted in damage to the shielding of multiple wires. The 
subject wire bundles contain wires associated with the following engine 
systems: electronic control, fire/overheat detection, starter air 
valve, airborne vibration monitoring, inlet probe heat, and fuel 
shutoff valve. The affected wires are routed through two clamps 
attached to a hydraulic pressure line, and the chafing may be caused by 
a high-frequency pump ripple transmitted from the engine-driven 
hydraulic pump. This chafing could potentially lead to dual wire faults 
from grounded, separated, or shorted wires; which could result in 
inadvertent takeoff thrust overboost, in-flight loss of thrust, or in-
flight engine shutdown.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Service Bulletin 767-
73A0049, Revision 2, dated April 27, 2000, which describes procedures 
for a one-time detailed visual inspection of certain wire bundles 
located in the aft section of the strut forward fairing panel of both 
engine struts to detect chafing damage, and repair or replacement of 
damaged wire bundles. The service bulletin also contains instructions 
for submitting a report of the inspection results to the manufacturer.
    The service bulletin references Boeing Standard Wiring Practices 
Manual for accomplishment of the repair of fire detection or overheat 
system wires.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between Service Bulletin and Proposed Rule

    Operators should note that, although the effectivity listing in the 
service

[[Page 56265]]

bulletin specifies ``all PW4000 powered 767 airplanes line numbers 0001 
through 0778,'' the applicability statement of this AD specifies 
``Model 767 series airplanes powered by Pratt & Whitney Model PW4000 
series engines.'' The FAA has determined that it is necessary to 
include line numbers 0779 and subsequent in the applicability of this 
AD because those additional airplanes are subject to the same unsafe 
condition as the airplanes specified in the service bulletin.
    Operators also should note that Section 3.B.1.a.(3) of the 
Accomplishment Instructions of the service bulletin describes 
instructions for repairing fire detection or overheat system wires in 
accordance with Boeing Standard Wiring Practices Manual, Subject 20-10-
13, Section 2. The FAA has determined that Section 2 of Subject 20-10-
13 does not provide the special instructions for repair of fire 
detection or overheat system wires. These repairs should be 
accomplished in accordance with Subject 20-10-13, Section 4B, of Boeing 
Standard Wiring Practices Manual. This section describes the assembly 
of splices with fire detection or overheat system wires.

Interim Action

    This is considered to be interim action. The inspection reports 
that are required by this AD will enable the manufacturer to obtain 
better insight into the nature, cause, and extent of the chafing, and 
eventually to develop final action to address the unsafe condition. 
Once final action has been identified, the FAA may consider further 
rulemaking.

Cost Impact

    There are approximately 147 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 61 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
2 work hours per airplane to accomplish the proposed inspection, and 
that the average labor rate is $60 per work hour. Based on these 
figures, the cost impact of the inspection proposed by this AD on U.S. 
operators is estimated to be $7,320, or $120 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up, planning time, or time 
necessitated by other administrative actions.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

Boeing: Docket 2000-NM-19-AD.

    Applicability: Model 767 series airplanes powered by Pratt & 
Whitney Model
    PW4000 series engines, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (d) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the potential for dual wire faults from grounded, 
separated, or shorted wires; which could result in inadvertent 
takeoff thrust overboost, in-flight loss of thrust, or engine 
shutdown, accomplish the following:

Detailed Visual Inspection

    (a) Prior to the accumulation of 10,000 hours time-in-service or 
within 180 days after the effective date of this AD, whichever 
occurs later: Perform a one-time detailed visual inspection of the 
wire bundles located in the aft section of the strut forward fairing 
panel of both engine struts to detect chafing damage, in accordance 
with Boeing Service Bulletin 767-73A0049, Revision 2, dated April 
27, 2000.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

Corrective Action

    (1) If any chafing damage of any wire bundle is detected: Prior 
to further flight, repair the wire bundle in accordance with the 
service bulletin, except as provided by paragraph (a)(2) of this AD.
    (2) If any chafing damage of the fire detection and/or overheat 
system wires is detected: Prior to further flight, repair the wires 
in accordance with the instructions described in Boeing Standard 
Wiring Practices Manual D6-54446, Subject 20-10-13, Section 4B, 
dated August 1, 1998. (The fire detection and/or overheat system 
wires can be repaired one time with a maximum of two splices for 
each wire segment, which is a temporary repair only.) Replace all 
spliced wires at the next scheduled strut system maintenance check, 
but no later than 6,000 flight hours or 18 months after the 
effective date of this AD, whichever occurs earlier, in accordance 
with the service bulletin.
    (3) If the fire detection and/or overheat system wires are 
spliced or replaced, conduct the system tests specified in Section 
3.B.1.a.(4) of the Accomplishment Instructions of the service 
bulletin.
    (b) Following accomplishment of paragraph (a) of this AD: Report 
inspection results, as described in Boeing Service Bulletin 767-
73A0049, Revision 2, dated April 27, 2000, to Boeing Commercial

[[Page 56266]]

Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207.
    (c) Where there are differences between the AD and the service 
bulletin the AD prevails.

Alternative Methods of Compliance

    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA. Operators shall submit their requests through an 
appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, Seattle ACO.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permit

    (e) 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.

    Issued in Renton, Washington, on September 12, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-23853 Filed 9-15-00; 8:45 am]
BILLING CODE 4910-13-P