[Federal Register Volume 62, Number 127 (Wednesday, July 2, 1997)]
[Proposed Rules]
[Pages 35711-35713]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-17285]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-39-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 767 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to certain Boeing Model 767
series airplanes, that currently requires an inspection to detect
damage of the wire bundles in the left side of the flight compartment
in the vicinity of the stowage box for the captain's oxygen mask, and
repair, if necessary; a continuity check on repaired wires;
installation of sleeving over the wire bundles; and rerouting of
[[Page 35712]]
the wire bundles. This action would require modifications of the
captain's and first officer's consoles in the flight compartment to
ensure adequate clearance between oxygen equipment and adjacent wire
bundles. This proposal is prompted by reports indicating that chafed
wiring and wire insulation wear occurred in the vicinity of the stowage
box for the captain's oxygen mask due to interference between oxygen
line fittings and adjacent wire bundles. The actions specified by the
proposed AD are intended to prevent such chafing and inadequate
clearance, which could result in electrical arcing and consequent
oxygen leakage in the vicinity of the stowage box; these conditions, if
not corrected, could result in a fire in the flight compartment.
DATES: Comments must be received by August 11, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-39-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.
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: Susan Letcher, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington;
telephone (425) 227-2670; 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.
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 97-NM-39-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-103, Attention: Rules
Docket No. 97-NM-39-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On October 2, 1995, the FAA issued AD 95-21-05, amendment 39-9390
(60 FR 52844, October 11, 1995), applicable to certain Boeing Model 767
airplanes, to require a one-time inspection to detect damage of the
wire bundles in the left side of the flight compartment in the vicinity
of the stowage box for the captain's oxygen mask, and repair, if
necessary; a continuity check on repaired wires; installation of
sleeving over the wire bundles; and rerouting of the wire bundles. That
action was prompted by reports of chafed wiring and minimal clearance
between the oxygen connector and the adjacent wire bundles in the
vicinity of the stowage box for the captain's oxygen mask. The
requirements of that AD are intended to prevent such chafing and
inadequate clearance, which could result in electrical arcing and
consequent oxygen leakage in the vicinity of the stowage box; these
conditions, if not corrected, could result in a fire in the flight
compartment.
Actions Since Issuance of Previous Rule
In the preamble to AD 95-21-05, the FAA indicated that the actions
required by that AD were considered ``interim action'' and that further
rulemaking action was being considered. The FAA now has determined that
further rulemaking action is indeed necessary, and this AD follows from
that determination.
Additionally, since the issuance of that AD, a number of reports
have been received that indicate interference between oxygen line
fittings on the stowage box for the captain's oxygen mask and adjacent
wire bundles. This condition, if not corrected, could cause wires on
the oxygen line fittings to chafe, which could lead to possible
electrical arcing with the fitting, a hole in the fitting, and an
oxygen leak; and result in an uncontrolled fire in the flight
compartment.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Alert Service Bulletin
767-35A0029, dated January 30, 1997, which describes procedures for
modifications of the captain's and first officer's consoles in the
flight compartment to ensure adequate clearance between oxygen
equipment and adjacent wire bundles. At the disconnect panel on the
captain's console, modification includes rerouting wires and installing
certain components. At the first officer's console, modification
includes installing certain components, such as a 90-degree backshell
on the electrical connector to the dimmer module and a new bracket
assembly. Ensuring adequate clearance between the oxygen system
components and adjacent wire bundles will reduce the potential for
future wire chafing on the consoles in the flight compartment.
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 supersede AD 95-21-05 to continue to require an
inspection to detect damage of the wire bundles in the left side of the
flight compartment in the vicinity of the stowage box for the captain's
oxygen mask, and repair, if necessary; a continuity check on repaired
wires; installation of sleeving over the wire bundles; and rerouting of
the wire bundles. The proposed AD also would require modifications of
the captain's and first officer's consoles in the flight compartment to
ensure adequate clearance between oxygen equipment and adjacent wire
bundles. The actions would be required to be accomplished in accordance
with the alert service bulletin described previously.
Cost Impact
There are approximately 568 Boeing Model 767 series airplanes of
the affected design in the worldwide fleet. The FAA estimates that 185
airplanes of U.S. registry would be affected by this proposed AD.
[[Page 35713]]
The actions that are currently required by AD 95-21-05 take
approximately 3 work hours per airplane to accomplish, at an average
labor rate of $60 per work hour. Required parts cost approximately $50
per airplane. Based on these figures, the cost impact of the currently
required actions on U.S. operators is estimated to be $42,550, or $230
per airplane.
The new actions that are proposed in this AD action would take
approximately 11 work hours per airplane to accomplish, at an average
labor rate of $60 per work hour. Required parts would cost
approximately $479 per airplane. Based on these figures, the cost
impact of the proposed requirements of this AD on U.S. operators is
estimated to be $210,715, or $1,139 per airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the current or proposed
requirements of this AD action, and that no operator would accomplish
those actions in the future if this AD were not adopted.
Regulatory Impact
The regulations proposed herein would not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
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 removing amendment 39-9390 (60 FR
52844, October 11, 1995), and by adding a new airworthiness directive
(AD), to read as follows:
Boeing: Docket 97-NM-39-AD. Supersedes AD 95-21-05, Amendment 39-
9390.
Applicability: Model 767 series airplanes, as listed in Boeing
Alert Service Bulletin 767-35A0029, dated January 30, 1997;
certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise 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 (c) 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 wire chafing and subsequent electrical arcing in the
vicinity of the stowage box for the captain's oxygen mask, which
could result in a fire in the flight compartment, accomplish the
following:
Restatement of Requirements of AD 95-21-05
(a) For Model 767 series airplanes having line positions 2
through 589 inclusive except VA801 through VA810 inclusive, VN684
through VN691 inclusive, and VW701: Within 45 days after October 26,
1995 (the effective date of AD 95-21-05, amendment 39-9390), inspect
to detect damage of the wire bundles in the left side of the flight
compartment in the vicinity of the stowage box for the captain's
oxygen mask, in accordance with Boeing Alert Service Bulletin 767-
35A0028, dated September 7, 1995.
(1) If no damage is detected, prior to further flight, install
protective sleeving on the wiring, and reroute the wire bundles, in
accordance with the alert service bulletin.
(2) If any damage is detected, prior to further flight,
accomplish the requirements of paragraphs (a)(2)(i) and (a)(2)(ii)
of this AD.
(i) Repair the wiring and perform a continuity check on each
repaired wire, in accordance with the alert service bulletin. And
(ii) Install protective sleeving on the wiring and reroute the
wire bundles, in accordance with the alert service bulletin.
New Requirements of This AD
(b) For all airplanes: Within 18 months after the effective date
of this AD, modify the airplane wiring in the vicinity of the
captain's and first officer's consoles, in accordance with Boeing
Alert Service Bulletin 767-35A0029, dated January 30, 1997.
Accomplishment of this modification constitutes terminating action
for the inspection requirements of this AD.
(c) 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, Transport Airplane Directorate. 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 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
(d) 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 June 26, 1997.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-17285 Filed 7-1-97; 8:45 am]
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