[Federal Register: November 17, 2003 (Volume 68, Number 221)]
[Proposed Rules]               
[Page 64825-64827]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17no03-14]                         

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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-120-AD]
RIN 2120-AA64

 
Airworthiness Directives; Bombardier Model DHC-8-401 and -402 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

[[Page 64826]]


ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Bombardier Model DHC-8-401 
and -402 airplanes. This proposal would require modifying the wiring of 
the rudder trim switch, inspecting all wiring on the back of the 
aileron/rudder trim control panel for chafing, and replacing any chafed 
wiring with new wiring. This action is necessary to prevent a short 
circuit on the aileron/rudder trim control panel that could cause a 
runaway condition of the rudder trim actuator, which could result in 
reduced controllability of the airplane. This action is intended to 
address the identified unsafe condition.

DATES: Comments must be received by December 17, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-120-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-120-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, 
123 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 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-120-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-120-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    Transport Canada Civil Aviation (TCCA), which is the airworthiness 
authority for Canada, notified the FAA that an unsafe condition may 
exist on certain Bombardier Model DHC-8-401 and -402 airplanes. TCCA 
advises that an incident of runaway of the rudder trim actuator 
occurred immediately following take-off. Investigation revealed a 
discrepancy in the wiring of the rudder trim control switch on the 
aileron/rudder trim control panel. This resulted in the rudder trim 
control switch being constantly enabled. In the event of a short-
circuit of a wire, this condition, if not corrected, could result in a 
runaway condition of the rudder trim actuator and consequent reduced 
controllability of the airplane.

Explanation of Relevant Service Information

    Bombardier has issued Alert Service Bulletin A84-27-13, Revision 
``B,'' dated January 12, 2002. That service bulletin describes 
procedures for modifying the wiring of the rudder trim switch, and 
performing a one-time general visual inspection of all wiring on the 
back of the aileron/rudder trim control panel for chafing, and 
replacement of any chafed wiring with new wiring. Accomplishment of the 
actions specified in the service bulletin is intended to adequately 
address the identified unsafe condition. TCCA classified this service 
bulletin as mandatory and issued Canadian airworthiness directive CF-
2002-15, dated February 20, 2002, to ensure the continued airworthiness 
of these airplanes in Canada.

FAA's Conclusions

    This airplane model is manufactured in Canada 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, TCCA has kept the FAA informed of 
the situation described above. The FAA has 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 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 rule would require accomplishment of 
the actions specified in the service bulletin described previously.

Cost Impact

    The FAA estimates that 12 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 1 work 
hour per airplane to accomplish the proposed actions, and that the 
average labor rate is $65 per

[[Page 64827]]

work hour. Based on these figures, the cost impact of the proposed AD 
on U.S. operators is estimated to be $780, or $65 per airplane.
    The 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. 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:

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket 2002-NM-120-
AD.

    Applicability: Model DHC-8-401 and -402 airplanes; certificated 
in any category; serial numbers 4005, 4006, 4008 through 4016 
inclusive, and 4018 through 4058 inclusive.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent a short circuit on the aileron/rudder trim control 
panel that could cause a runaway condition of the rudder trim 
actuator, which could result in reduced controllability of the 
airplane, accomplish the following:

Modification, Inspection, and Corrective Action

    (a) Within 90 days after the effective date of this AD, do the 
actions in paragraphs (a)(1) and (a)(2) of this AD, per the 
Accomplishment Instructions of Bombardier Alert Service Bulletin 
A84-27-13, Revision ``B,'' dated January 12, 2002.
    (1) Modify the wiring of the rudder trim switch.
    (2) Before further flight after accomplishing the modification 
required by paragraph (a)(1) of this AD: Perform a one-time general 
visual inspection of all wiring on the back of the aileron/rudder 
trim control panel for chafing. Before further flight, replace any 
chafed wiring with new wiring.

    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.''

Previously Accomplished Actions

    (b) Modifications and inspections accomplished before the 
effective date of this AD per Bombardier Alert Service Bulletin A84-
27-13, Revision ``A,'' dated January 9, 2002, are acceptable for 
compliance with the corresponding actions required by paragraph (a) 
of this AD.

Parts Installation

    (c) As of the effective date of this AD, no person may install 
aileron/rudder trim control panel having part number 82410608-005 on 
any airplane, unless the control panel has been modified and 
inspected per the requirements of this AD.

Alternative Methods of Compliance

    (d) In accordance with 14 CFR 39.19, the Manager, New York 
Aircraft Certification Office (ACO), 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-2002-15, dated February 20, 2002.


    Issued in Renton, Washington, on November 10, 2003.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-28608 Filed 11-14-03; 8:45 am]

BILLING CODE 4910-13-P