[Federal Register Volume 69, Number 52 (Wednesday, March 17, 2004)]
[Proposed Rules]
[Pages 12592-12594]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-5945]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-171-AD]
RIN 2120-AA64


Airworthiness Directives; BAE Systems (Operations) Limited Model 
BAe 146 Series Airplanes

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 BAE Systems (Operations) 
Limited Model BAe 146 series airplanes. This proposal would require 
repetitive detailed inspections for heat damage to any in-line splice 
in the auxiliary power unit (APU) and integrated drive generator (IDG) 
feeder cable circuits, and corrective action if necessary. This 
proposed AD also would provide for optional terminating action for the 
repetitive inspections. This action is necessary to prevent overheating 
of the in-line splices of the APU and IDG feeder cables, which can lead 
to smoke, fumes, and possible fire in the flight deck and cabin. This 
action is intended to address the identified unsafe condition.

DATES: Comments must be received by April 16, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-171-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. 2003-NM-171-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 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from British Aerospace Regional Aircraft American Support, 
13850 Mclearen Road, Herndon, Virginia 20171. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1175; fax (425) 227-1149.

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 2003-NM-171-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. 2003-NM-171-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, notified the FAA that an unsafe 
condition may exist on certain BAE Systems (Operations) Limited Model 
BAe 146 series airplanes. The CAA advises that it received reports of 
in-line splices in the auxiliary power unit (APU) feeder cables being 
damaged by overheating. The CAA considers that splices in the 
integrated drive generator (IDG) feeder cables could also be subject to 
overheating. Poor joint splicing of electrical cables can lead to 
overheating that involves conductor melting. These failures can result 
in open APU generator or IDG circuits, followed by the associated 
generator tripping off-line. Overheating of the in-line splices of the 
APU or IDG feeder cables, if not corrected, can lead to smoke, fumes, 
and possible fire in the flight deck and cabin.

Explanation of Relevant Service Information

    BAE Systems (Operations) Limited has issued Inspection Service 
Bulletin ISB.24-139, dated April 2, 2003, which describes procedures 
for repetitive detailed inspections for heat damage to any in-line 
splice in the APU and IDG feeder cable circuits, and corrective action 
if necessary. The service bulletin refers to additional service 
bulletins for corrective and terminating actions, as follows:

     BAE Systems (Operations) Limited Modification 
Service Bulletin SB.24-82-36097A&B, Revision No. 2, dated September 23, 
1992, which describes procedures for modification of the APU feeders 
involving installation of an improved splice, and installation of 
continuous size 6 cables without splices.
     BAE Systems (Operations) Limited Modification 
Service Bulletin SB.24-85-01253A, Revision No. 1, dated March 15, 1991, 
which describes procedures for modification of the IDG feeders 
involving installation of an improved splice.
     BAE Systems (Operations) Limited Modification 
Service Bulletin SB.24-98-01253B, dated October 30, 1992, which 
describes procedures for modification of the IDG feeders involving 
installation of continuous size 6 cables without splices.
     BAE Systems (Operations) Limited Modification 
Service Bulletin SB.24-92-01203C, Revision 1, dated August 27, 2002, 
which describes procedures for modification of the IDG feeders 
involving installation of size 4 cables

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that have terminal blocks instead of splices.

    Per BAE Systems (Operations) Limited Inspection Service Bulletin 
ISB.24-139, dated April 2, 2003, accomplishment of any of the 
modifications described previously eliminates the need for the 
repetitive inspections of the APU or IDG feeders, as applicable.
    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition. The CAA 
classified BAE Systems (Operations) Limited Inspection Service Bulletin 
ISB.24-139, dated April 2, 2003, as mandatory and issued British 
airworthiness directive 005-04-2003 to ensure the continued 
airworthiness of these airplanes in the United Kingdom.

FAA's Conclusions

    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the CAA, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in BAE Systems (Operations) Limited Inspection 
Service Bulletin ISB.24-139, dated April 2, 2003, except as discussed 
below under ``Difference Between Proposed Rule and Certain Referenced 
Service Bulletin.''
    This proposed AD also would provide for optional terminating action 
for the repetitive inspections. Consistent with the findings of the 
CAA, the proposed AD would allow repetitive inspections to continue in 
lieu of the terminating action. In making this determination, we 
considered that long-term continued operational safety in this case 
will be adequately ensured by repetitive inspections of in-line splices 
in the APU and IDG feeder cables to detect heat damage before it 
represents a hazard to the airplane.

Difference Between Proposed Rule and Certain Referenced Service 
Bulletin

    Operators should note that, although the Accomplishment 
Instructions of BAE Systems (Operations) Limited Inspection Service 
Bulletin ISB.24-139, dated April 2, 2003, describes procedures for 
reporting inspection findings to the airplane manufacturer, this 
proposed AD would not require that action.

Cost Impact

    The FAA estimates that 17 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 6 work 
hours per airplane to accomplish the proposed inspections, and that the 
average labor rate is $65 per work hour. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$6,630, or $390 per airplane, per inspection cycle.
    The optional terminating action, if done, would take approximately 
between 5 and 30 work hours per airplane, at an average labor rate of 
$65 per work hour. Required parts would cost approximately between $744 
and $1,379 per airplane. Based on these figures, we estimate the cost 
of the optional terminating action to be between $1,069 and $2,847 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 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:

BAE Systems (Operations) Limited (Formerly British Aerospace 
Regional Aircraft): Docket 2003-NM-171-AD.
    Applicability: Model BAE 146 series airplanes, as identified in 
BAE Systems (Operations) Limited Inspection Service Bulletin ISB.24-
139, dated April 2, 2003; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent overheating of the in-line splices of the auxiliary 
power unit (APU) and integrated drive generator (IDG) feeder cables, 
which can lead to smoke, fumes, and possible fire in the flight deck 
and cabin, accomplish the following:

Inspection

    (a) Within 6 months after the effective date of this AD, do a 
detailed inspection for heat damage to any in-line splice in the APU 
and IDG feeder cables, per the Accomplishment Instructions of BAE 
Systems (Operations) Limited Inspection Service Bulletin ISB.24-139, 
dated April 2, 2003. If no heat damage is found, repeat the 
inspections thereafter at intervals not to exceed 12 months. 
Although the service bulletin specifies to report inspection 
findings to the airplane manufacturer, this AD does not include such 
a requirement.

    Note 1: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or assembly to detect damage, 
failure, or

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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

    (b) If any heat damage is found during any inspection done per 
paragraph (a) of this AD: Prior to further flight, modify the 
damaged in-line splices in the APU and/or IDG feeder cable circuits, 
per paragraph 2.F., ``Terminating Action,'' of the Accomplishment 
Instructions of BAE Systems (Operations) Limited Inspection Service 
Bulletin ISB.24-139, dated April 2, 2003, as applicable.

Optional Terminating Action

    (c) Modifying the in-line splices in the APU and/or the IDG 
feeder cable circuits, per the Terminating Action instructions of 
the Accomplishment Instructions of BAE Systems (Operations) Limited 
Inspection Service Bulletin ISB.24-139, dated April 2, 2003, 
constitutes terminating action for this AD.

Alternative Methods of Compliance

    (d) In accordance with 14 CFR 39.19, the Manager, International 
Branch, ANM-116, Transport Airplane Directorate, FAA, is authorized 
to approve alternative methods of compliance for this AD.

    Note 2: The subject of this AD is addressed in British 
airworthiness directive 005-04-2003.


    Issued in Renton, Washington, on March 5, 2004.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-5945 Filed 3-16-04; 8:45 am]
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