[Federal Register: October 20, 2003 (Volume 68, Number 202)]
[Proposed Rules]               
[Page 59892-59894]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20oc03-11]                         

========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

========================================================================



[[Page 59892]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-11-AD]
RIN 2120-AA64

 
Airworthiness Directives; Bombardier Model DHC-8-102, -103, -106, 
-201, -202, -301, -311, and -315 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Bombardier Model 
DHC-8-102, -103, -106, -201, -202, -301, -311, and -315 airplanes, that 
currently requires a one-time inspection to detect chafing of 
electrical wires in the cable trough below the cabin floor; repair, if 
necessary; installation of additional tie-mounts and tie-wraps; and 
application of sealant to rivet heads. This action would add an 
additional modification of the electrical wires in certain sections. 
The actions specified by the proposed AD are intended to prevent 
chafing of electrical wires, which could result in an uncommanded 
shutdown of an engine during flight. This action is intended to address 
the identified unsafe condition.

DATES: Comments must be received by November 19, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-11-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: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must 
contain ``Docket No. 2002-NM-11-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 Bombardier, Inc., Bombardier Regional Aircraft Division, 
Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information 
may be examined at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the FAA, New York Aircraft 
Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New 
York.

FOR FURTHER INFORMATION CONTACT: Douglas G. Wagner, Aerospace Engineer, 
Systems and Flight Test Branch, ANE-172, FAA, New York Aircraft 
Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New 
York 11581; telephone (516) 256-7506; fax (516) 568-2716.

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:
    [sbull] 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.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] 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 2002-NM-11-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. 2002-NM-11-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On September 28, 1999, the FAA issued AD 99-21-09, amendment 39-
11352 (64 FR 54199, October 6, 1999), which superseded AD 98-20-14, 
amendment 39-10781 (63 FR 50501, September 22, 1998), applicable to 
certain Bombardier Model DHC-8-102, -103, -106, -201, -202, -301, -311, 
and -315 series airplanes. That AD requires a one-time inspection to 
detect chafing of electrical wires in the cable trough below the cabin 
floor; repair, if necessary; installation of additional tie-mounts and 
tie-wraps; and application of sealant to rivet heads. That action was 
prompted by issuance of mandatory continuing airworthiness information 
by a foreign civil airworthiness authority. The requirements of that AD 
are intended to prevent chafing of electrical wires, which could result 
in an uncommanded shutdown of an engine during flight.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 99-21-09, Transport Canada Civil Aviation 
(TCCA), which is the airworthiness authority for Canada, has informed 
us that an uncommanded engine shutdown during flight occurred on a 
Bombardier Model DHC-8 airplane. The shutdown was due to a short 
circuit between adjacent wires located in the cable trough below the 
cabin floor, which sent a 28-volt signal to the fuel shutoff valve. 
Investigation revealed that the short

[[Page 59893]]

circuit was caused by chafing of the wires on the sharp edges of the 
cherrymax rivets in the cable trough. Such chafing of electrical wires 
could result in an uncommanded shutdown of an engine during flight.

Explanation of Relevant Service Information

    Bombardier has issued Service Bulletin 8-53-80, Revision ``A'', 
dated July 25, 2000, which describes procedures for an additional 
modification of the electrical wires in the cable trough below the 
cabin floor. The modification is to be done in sections X510.00 to 
X580.50 of the cable trough; those sections were inadvertently omitted 
from the modification specified in Bombardier Service Bulletin 8-53-66, 
dated March 27, 1998 (the service bulletin referenced in the existing 
AD). TCCA classified Service Bulletin 8-53-80, Revision ``A'', as 
mandatory and issued Canadian airworthiness directive CF-1998-08R2, 
dated July 10, 2000, to ensure the continued airworthiness of these 
airplanes in Canada.

FAA's Conclusions

    These airplane models are manufactured in Canada and are 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, TCCA has kept us informed of the 
situation described above. We have examined the findings of TCCA, 
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 AD

    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 supersede AD 99-21-09 to 
continue to require a one-time inspection to detect chafing of 
electrical wires in the cable trough below the cabin floor; repair, if 
necessary; installation of additional tie-mounts and tie-wraps; and 
application of sealant to rivet heads. The proposed AD would add an 
additional modification of the electrical wires in certain sections. 
The actions would be required to be accomplished in accordance with the 
service bulletin described previously, except as discussed below.

Difference Between This Proposed AD and Service Bulletin

    Although the service bulletin specifies to submit certain 
information to the manufacturer, the proposed AD does not include such 
a requirement.

Cost Impact

    There are approximately 173 airplanes of U.S. registry that would 
be affected by this proposed AD.
    The actions that are currently required by AD 99-21-09 take between 
80 and 100 work hours per airplane (depending on the airplane model) to 
accomplish, at an average labor rate of $65 per work hour. Required 
parts are provided by the manufacturer at no cost to the operator. 
Based on these figures, the cost impact of the currently required 
actions is estimated to be between $5,200 and $6,500 per airplane.
    The additional modification that is proposed in this AD action 
would take approximately 10 work hours per airplane to accomplish, at 
an average labor rate of $65 per work hour. Required parts would be 
provided by the manufacturer at no cost to the operator. Based on these 
figures, the cost impact of the proposed modification on U.S. operators 
is estimated to be $112,450, or $650 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. 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 removing amendment 39-11352 (64 FR 
54199, October 6, 1999), and by adding a new airworthiness directive 
(AD), to read as follows:

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket 2002-NM-11-
AD. Supersedes AD 99-21-09, Amendment 39-11352.

    Applicability: Model DHC-8-102, -103, -106, -201, -202, -301, -
311, and -315 series airplanes; serial numbers 3 through 540 
inclusive, excluding serial number 462; certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent chafing of electrical wires, which could result in an 
uncommanded shutdown of an engine during flight, accomplish the 
following:

Restatement of Requirements of AD 99-21-09

One-Time Inspection, Corrective Action, and Modification

    (a) Perform a one-time general visual inspection to detect 
chafing of electrical wires in the cable trough below the cabin 
floor; install additional tie-mounts and tie-wraps; and apply 
sealant to rivet heads (reference Bombardier Modification 8/2705); 
in accordance with Bombardier Service Bulletin 8-53-66, dated March 
27, 1998, at the time specified in paragraph (a)(1) or (a)(2) of 
this AD, as applicable. If any chafing is detected during the 
inspection required by this paragraph, prior to further flight, 
repair in accordance with the service bulletin.


[[Page 59894]]


    Note 1: For the purposes of this AD, a general visual inspection 
is defined as: ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made from within 
touching distance unless otherwise specified. A mirror may be 
necessary to enhance visual access to all exposed surfaces in the 
inspection area. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or droplight and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

    (1) For airplanes having serial numbers 3 through 519 inclusive, 
excluding serial number 462: Inspect within 36 months after October 
27, 1998 (the effective date of AD 98-20-14, amendment 39-10781).
    (2) For airplanes having serial numbers 520 through 540 
inclusive: Inspect within 36 months after November 10, 1999 (the 
effective date of AD 99-21-09, amendment 39-11352, which superseded 
AD 98-20-14), or at the next ``C'' check, whichever occurs first.

New Requirements of This AD

Modification

    (b) For all airplanes: Within 36 months after the effective date 
of this AD; modify the electrical wires in the cable trough below 
the cabin floor at Sections X510.00 to X580.50 (including a general 
visual inspection and any applicable repair) per Part III, 
paragraphs 1 through 9 and 12 through 20, of the Accomplishment 
Instructions of Bombardier Service Bulletin 8-53-80, Revision ``A'', 
dated July 25, 2000. Any applicable repair must be done before 
further flight.

Alternative Methods of Compliance

    (c) In accordance with 14 CFR 39.19, the Manager, New York 
Aircraft Certification Office, FAA, is authorized to approve 
alternative methods of compliance for this AD.

    Note 2: The subject of this AD is addressed in Canadian 
airworthiness directive CF-1998-08R2, dated July 10, 2000.


    Issued in Renton, Washington, on October 14, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-26368 Filed 10-17-03; 8:45 am]

BILLING CODE 4910-13-P