[Federal Register Volume 61, Number 231 (Friday, November 29, 1996)]
[Proposed Rules]
[Pages 60653-60655]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-30412]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-239-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747-100, -200, and -300
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain Boeing Model 747-100, -
200, and -300 series airplanes. This proposal would require the
replacement of certain switches located behind the cabin attendant's
panel at one of the airplane's doors with new, improved switches. This
proposal is prompted by reports indicating that fires have occurred on
some airplanes due to the internal failure of some of these switches.
The actions specified by the proposed AD are intended to prevent the
installation and use of switches that could short circuit when they
fail, and consequently cause fire and smoke aboard the airplane.
DATES: Comments must be received by January 29, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-239-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
[[Page 60654]]
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Forrest Keller, Senior Aerospace
Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington;
telephone (206) 227-2790; fax (206) 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 96-NM-239-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. 96-NM-239-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received several reports indicating that fires and
smoke have occurred aboard Model 747-100 series airplanes behind the
cabin attendant's panel at door 4 right. These incidents, reported by
four operators, occurred during flight or after landing.
Investigation revealed that the fires were the result of internal
failures in switches S4 and/or S5, or switches S7 and S8. These
failures caused a short circuit between the switch and its ground.
Switches of this type also are found on Model 747-200 and -300 series
airplanes. The installation and use of a switch that could short
circuit when it fails, if not corrected, could consequently result in
fire and smoke aboard the airplane.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Alert Service Bulletin
747-33A2252, dated August 1, 1996, which describes procedures for the
replacement of switches S4 and/or S5, or switches S7 and S8 that are
installed on the cabin attendant's panel at door 4 right with new,
improved switches. In the event that an improved switch fails
internally, there will be no short circuit between the switch and its
ground; therefore, the potential for fire or smoke to occur is reduced.
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 the replacement of switches S4 and/or S5, or
switches S7 and S8 that are installed on the cabin attendant's panel at
door 4 right with new, improved switches. The actions would be required
to be accomplished in accordance with the Boeing alert service bulletin
described previously.
Cost Impact
There are approximately 648 Boeing Model 747-100, -200, and -300
series airplanes of the affected design in the worldwide fleet.
The FAA estimates that 167 airplanes of U.S. registry would be
affected by this proposed AD. It would take approximately 3 work hours
per airplane to accomplish the proposed actions, at an average labor
rate of $60 per work hour. Required parts would cost between $270 and
$556, depending on the parts kit that is needed. Based on these
figures, the cost impact of the proposed AD on U.S. operators is
estimated to be between $75,150 and $122,912, or between $450 and $736
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.
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 adding the following new
airworthiness directive:
Boeing: Docket 96-NM-239-AD.
Applicability: Model 747-100, -200, and -300 series airplanes;
as listed in Boeing Alert Service Bulletin 747-33A2252, dated August
1, 1996; 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
[[Page 60655]]
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 the installation and use of switches in the cabin
attendant's panel at door 4 right that could short circuit when they
fail, and consequently cause fire and smoke aboard the airplane,
accomplish the following:
(a) Within 6 months after the effective date of this AD, replace
switches S4 and/or S5, or switches S7 and S8 that are installed in
the cabin attendant's panel at door 4 right with new switches, in
accordance with Boeing Alert Service Bulletin 747-33A2252, dated
August 1, 1996.
(b) As of the effective date of this AD, no person shall install
at door 4 right of any airplane an attendant's panel having a part
number identified in the ``Existing Part Number'' column of
paragraph II.D. of Boeing Alert Service Bulletin 747-33A2252, dated
August 1, 1996.
(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 November 21, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-30412 Filed 11-27-96; 8:45 am]
BILLING CODE 4910-13-U
