[Federal Register Volume 66, Number 108 (Tuesday, June 5, 2001)]
[Proposed Rules]
[Pages 30112-30114]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-14041]


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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: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Boeing Model 767 series 
airplanes, that would have required 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 new 
action revises the proposed rule by adding replacement of wires 
repaired by splicing and damaged wires that require splicing, and 
replacement of the support brackets of the existing wire bundles with 
new brackets and clamps, which would terminate the existing 
requirements. The actions specified by this new proposed AD are 
intended 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 July 2, 2001.

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 a.m. and 3 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 action 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 action 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

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Boeing Model 767 series airplanes, was published as a notice of 
proposed rulemaking (NPRM) in the Federal Register on September 18, 
2000 (65 FR 56264). That NPRM would have required 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. That NPRM 
was prompted by reports indicating several incidents of severe wire 
chafing of certain wire bundles in both engine struts. That condition, 
if not corrected, could result in the potential for dual wire faults 
from grounded, separated, or shorted wires; and consequent inadvertent 
takeoff thrust overboost, in-flight loss of thrust, or engine shutdown.

Actions Since Issuance of Notice of Proposed Rulemaking (NPRM)

    Since issuance of the NPRM, the FAA has reviewed and approved 
Boeing Service Bulletin 767-73A0049, Revision 3, dated December 20, 
2000, which contained certain changes from Revision 2 of the service 
bulletin (referenced as the appropriate source of service information 
for accomplishment of the actions specified in the proposed rule). 
Revision 3 adds airplanes that have been manufactured since the 
issuance of the NPRM; updates warranty information; corrects a wire 
part number, and clarifies repair/splice instructions for fire zone 
wiring. Revision 3 has been added as a revised source of service 
information for accomplishment of the specified actions, and the 
references to Revision 2 have been removed from the supplemental NPRM. 
Additionally, paragraph (a)(2) of the NPRM has been revised. The 
reference to the repair of the wires as specified in the wiring 
practices manual has been removed

[[Page 30113]]

from paragraph (a)(2) because Revision 3 corrects the errors contained 
in Revision 2 describing repair/splice instructions for wires installed 
in the fire zone. Paragraph (a)(3) has been changed to a new (b)(1), 
which specifies the replacement of any wires that are damaged and 
require a splice repair.
    The FAA also has reviewed and approved Boeing Service Bulletin 767-
73A0049, Revision 4, dated April 5, 2001. Revision 4 is essentially the 
same as Revision 3 (above), but eliminates one airplane that was 
inadvertently included in the effectivity section of Revision 3. 
Revision 4 has been added to the supplemental NPRM as an additional 
source of service information for accomplishment of the specified 
actions.

Comments

    Due consideration has been given to the comments received in 
response to the NPRM. Certain comments have resulted in changes to the 
NPRM.

Terminating Action

    One commenter asks that Boeing Service Bulletin 767-73-0051, dated 
December 20, 2000, replace Boeing Service Bulletin 767-73A0049, which 
was referenced as the appropriate source of service information for 
accomplishment of the actions specified in the NPRM. The commenter 
states that the new service bulletin would provide final corrective 
action for the unsafe condition, and would eliminate the need for 
further rulemaking. Another commenter states that the action specified 
in the NPRM was interim action and asks that the manufacturer's final 
action be included in the supplemental NPRM.
    The FAA partially concurs with the commenters. Since the issuance 
of the NPRM, the FAA has reviewed and approved Boeing Service Bulletin 
767-73-0051. The service bulletin describes procedures for replacement 
of the support brackets of the existing wire bundle with a new bridge 
bracket, support bracket, and wire bundle clamps. Accomplishment of the 
replacement eliminates the need for the inspection and corrective 
action required by the NPRM, and as the final action, addresses the 
unsafe condition. Additionally, the applicability in the NPRM has been 
changed to the same effectivity listed in the service bulletin, because 
airplanes having line number 822 and after have been delivered with the 
new bracket installed. A new paragraph (b) has been added to include 
the replacement as terminating action, and a spares paragraph has been 
added to ensure that existing parts are not used for the replacement. 
However, the new service bulletin (above) will not replace the service 
bulletin referenced in the NPRM because the existing actions will 
continue to be required until accomplishment of the terminating action.

Conclusion

    Since these changes expand the scope of the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.

Differences Between Service Bulletin and Proposed Rule

    Boeing Service Bulletin 767-73-0049 recommends that damaged wires 
repaired by splicing, as specified in paragraph (a)(2) of the NPRM, be 
replaced at the next scheduled strut system maintenance check. This 
supplemental NPRM would require that any wires repaired by splicing, 
and any damaged wires that need to be spliced, be replaced concurrent 
with the incorporation of the terminating action specified in Boeing 
Service Bulletin 767-73-0051.
    Although Boeing Service Bulletin 767-73-0051 recommends doing the 
replacement at the next convenient opportunity where facilities and 
manpower are available, the FAA has determined that this compliance 
time may not ensure that the identified unsafe condition is addressed 
in a timely manner. In developing an appropriate compliance time for 
this proposed AD, the FAA considered not only the manufacturer's 
recommendation, but the degree of urgency associated with addressing 
the subject unsafe condition, the average utilization of the affected 
fleet, and the time necessary to perform the proposed AD. In light of 
all of these factors, the FAA finds a compliance time of within 6,000 
flight hours or 18 months after the effective date of this AD, 
whichever occurs later, to be warranted, in that it represents an 
appropriate interval of time allowable for affected airplanes to 
continue to operate without compromising safety.

Cost Impact

    There are approximately 185 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 79 airplanes of U.S. registry 
would be affected by this proposed AD.
    It would take approximately 2 work hours per airplane to accomplish 
the proposed inspection, at an average labor rate of $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 $9,480, or $120 per 
airplane.
    It would take approximately 3 work hours per airplane to accomplish 
the proposed replacement, at an average labor rate of $60 per work 
hour. Required parts would cost approximately $1,570 per airplane. 
Based on these figures, the cost impact of the replacement proposed by 
this AD on U.S. operators is estimated to be $138,250, or $1,750 per 
airplane.
    The cost impact figures discussed above are 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 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

[[Page 30114]]

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 as listed in Boeing 
Service Bulletin 767-73-0051, dated December 20, 2000, 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 per paragraph (e) 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: Do 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, per Boeing 
Service Bulletin 767-73A0049, Revision 3, dated December 20, 2000, 
or Revision 4, dated April 5, 2001.

    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: Before 
further flight, repair the wire bundle per the service bulletin, 
except as provided by paragraph (a)(2) of this AD.
    (2) Replace all spliced wires with new wires per the service 
bulletin, concurrent with accomplishment of the terminating action 
required by paragraph (b)(2) of this AD.

Terminating Action

    (b) Within 6,000 flight hours or 18 months after the effective 
date of this AD, whichever occurs later, do the actions specified in 
paragraphs (b)(1) and (b)(2) of this AD per the Accomplishment 
Instructions of Boeing Service Bulletin 767-73-0051, dated December 
20, 2000.
    (1) Do a detailed visual inspection of the wire bundles to 
detect chafing damage; if any damaged wires are found, replace the 
wires that require a splice repair with new wires concurrent with 
accomplishment of the terminating action specified in paragraph 
(b)(2) of this AD.
    (2) Replace the existing support bracket of the wire bundle with 
a new bridge bracket, support bracket, and wire bundle clamps. 
Accomplishment of this replacement terminates the requirements of 
this AD.

Report Inspection Results

    (c) Following accomplishment of paragraph (a) or (b) of this AD: 
Report inspection results, as described in Boeing Service Bulletin 
767-73A0049, Revision 3, dated December 20, 2000, or Revision 4, 
dated April 5, 2001, to Boeing Commercial Airplane Group, P.O. Box 
3707, Seattle, Washington 98124-2207.

Spares

    (d) As of the effective date of this AD, no person shall install 
on any airplane any bracket identified in the ``Existing Part 
Number'' column of Paragraph 2.E. of Boeing Service Bulletin 767-73-
0051, dated December 20, 2000.

Alternative Methods of Compliance

    (e) 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

    (f) Special flight permits may be issued per Secs. 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 May 30, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-14041 Filed 6-4-01; 8:45 am]
BILLING CODE 4910-13-U