[Federal Register Volume 60, Number 173 (Thursday, September 7, 1995)]
[Proposed Rules]
[Pages 46542-46544]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-22211]




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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-53-AD]


Airworthiness Directives; Boeing Model 747-400 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 747-
400 series airplanes, 

[[Page 46543]]
that currently requires replacement of electrical wiring to the fuel 
shutoff valve for each engine. This action would require replacement of 
the fuel shutoff valve wire and sleeve with a wire in two non-metallic 
sleeves in the conduit in the struts of each engine. This proposal is 
prompted by reports of additional occurrences of chafing and shorting 
of the wiring of the engine fuel shutoff valves. The actions specified 
by the proposed AD are intended to prevent such chafing and shorting, 
which could result in the pilot's inability to shut off the supply of 
fuel in the event of an engine fire.

DATES: Comments must be received by November 1, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-53-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: Stephen Oshiro, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; 
telephone (206) 227-2793; 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 95-NM-53-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. 95-NM-53-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.
Discussion

    On June 12, 1989, the FAA issued AD 89-14-04, amendment 39-6246 (54 
FR 27157, June 28, 1989), applicable to certain Boeing Model 747-400 
series airplanes, to require replacement of electrical wiring to the 
fuel shutoff valve for each engine. That action was prompted by reports 
of the fuel shutoff valve wiring shorting to the surrounding electrical 
conduit, which resulted in circuit breaker tripping and inability to 
operate the associated fuel shutoff valve. The requirements of that AD 
are intended to preserve the pilot's ability to shut off the supply of 
fuel in the event of an engine fire.
    Since the issuance of that AD, the FAA has received reports of 
additional occurrences of chafing and shorting of the wiring of the 
engine fuel shutoff valves on Model 747-400 series airplanes. 
Subsequently, Boeing developed a new installation consisting of a wire 
in two sleeves (non-metallic, open weave braided sleeve inside 
industrial wall thickness teflon) that will improve the protection of 
the fuel shutoff valve wire.
    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-28A2186, dated January 19, 1995, which describes procedures for 
replacement of the fuel shutoff valve wire and sleeve with a wire in 
two non-metallic sleeves in the conduit in the struts of each engine.
    The FAA has determined that accomplishment of this replacement of 
the fuel shutoff valve wire and sleeve with a wire with two non-
metallic sleeves in the conduit in the struts of each engine will 
positively address the unsafe condition identified as inability to shut 
off the supply of fuel to an engine.
    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 89-14-04 to require replacement of the 
wire and sleeve with a single wire in two non-metallic sleeves in the 
conduit in the struts of each engine. The actions would be required to 
be accomplished in accordance with the alert service bulletin described 
previously.
    The modification that was previously required by AD 89-14-04 will 
effectively be removed when the modification required by this proposed 
AD is installed. Additionally, those airplanes on which the previously-
required modification had not been accomplished will require no 
additional work with the installation of the new proposed modification.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this notice to clarify this long-standing requirement.
    There are approximately 311 Model 747-400 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 38 
airplanes of U.S. registry would be affected by this proposed AD, that 
it would take approximately 80 work hours per airplane to accomplish 
the proposed actions, and that the average labor rate is $60 per work 
hour. Required parts would cost approximately $673 per airplane. Based 
on these figures, the total cost impact of the proposed AD on U.S. 
operators is estimated to be $207,974, or $5,473 per airplane.
    The total 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 AD were not adopted. 

[[Page 46544]]

    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), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-6246 (54 FR 
27157, June 28, 1989), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 95-NM-53-AD. Supersedes AD 89-14-04, Amendment 39-
6246.

    Applicability: Model 747-400 series airplanes; line positions 
696 through 1046 inclusive, except airplane variable numbers RT502 
and RU032 (airplane serial numbers 24062 and 25780, respectively); 
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 use the authority 
provided in paragraph (b) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.

    To prevent the inability to shut off the supply of fuel in the 
event of an engine fire, accomplish the following:

    (a) Within 12 months after the effective date of this AD, 
replace the fuel shutoff valve wire and sleeve with a wire in two 
non-metallic sleeves in the conduit in the struts of each engine, in 
accordance with Boeing Alert Service Bulletin 747-28A2186, dated 
January 19, 1995.

    Note 2: Replacements accomplished prior to the effective date of 
this amendment in accordance with Boeing Alert Service Bulletin 747-
54A2157, dated January 12, 1995, or Revision 1, dated August 3, 
1995; or Boeing Alert Service Bulletin 747-54A2156, dated December 
15, 1994, or Revision 1, dated July 20, 1995; are considered 
acceptable for compliance with the replacements specified in this 
amendment.

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

    (c) 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 August 31, 1995.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.

[FR Doc. 95-22211 Filed 9-6-95; 8:45 am]

BILLING CODE 4910-13-U