[Federal Register Volume 59, Number 27 (Wednesday, February 9, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-2914]


[[Page Unknown]]

[Federal Register: February 9, 1994]


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


DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-207-AD]

 

Airworthiness Directives; Canadair Model CL-600-1A11, -2A12, and 
-2B16 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 Canadair Model CL-600-
1A11, -2A12, and -2B16 series airplanes. This proposal would require a 
test of the engine throttle quadrant to determine if the throttle lever 
bypasses the idle stop into the shut-off position, and modification of 
the throttle quadrant or replacement of the throttle quadrant with a 
modified unit. This proposal is prompted by reports of unintentional 
engine shutdown on Model CL-600-2A12 and -2B16 series airplanes. The 
actions specified by the proposed AD are intended to prevent 
inadvertent shutdown of an engine while the airplane is taxiing or in 
flight.

DATES: Comments must be received by April 5, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-207-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.
    The service information referenced in the proposed rule may be 
obtained from Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 
6087, Station A, Montreal, Quebec H3C 3G9, Canada. This information may 
be examined at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 181 South Franklin 
Avenue, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT: Raymond J. O'Neill, Aerospace 
Engineer, Propulsion Branch, ANE-174, FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 181 South Franklin 
Avenue, room 202, Valley Stream, New York 11581; telephone (516) 791-
7421; fax (516) 791-9024.

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 93-NM-207-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. 93-NM-207-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion -

    Transport Canada Aviation, which is the airworthiness authority for 
Canada, recently notified the FAA that an unsafe condition may exist on 
certain Canadair Model CL-600-1A11, -2A12, and -2B16 series airplanes. 
Transport Canada Aviation advises that it has received two reports of 
unintentional engine shutdown: One incident occurred during flight on a 
Model CL-600-2A12, the other occurred on a Model CL-600-2B16 while the 
airplane was on the ground. In both cases, engine shutdown occurred 
when the throttle lever over-rode the idle stop during throttle 
retardation. The throttle lever then moved directly to the shut-off 
position. -
    Tests results performed on throttle quadrants that were both 
installed and not installed revealed that, in some cases, the idle stop 
spring-loaded pawl can be lifted sufficiently for it to pass over the 
idle stop without pressure being applied to the release latch. This 
condition becomes more apparent when the friction device on the 
quadrant is loaded and a side load is applied to the throttle lever. 
This condition, if not corrected, could result in inadvertent shutdown 
of an engine while the airplane is taxiing or in flight. -
    Model CL-600-1A11 series airplanes are similar in type design to 
the airplane models on which the reported incidents occurred. 
Therefore, all three models are subject to the addressed unsafe 
condition. -
    Bombardier has issued Canadair Alert Service Bulletin A600-0615, 
dated June 10, 1992 (for Model CL-600-1A11 series airplanes), and 
Canadair Alert Service Bulletin A601-0374 (for Model CL-600-2A12 and -
2B16 series airplanes), Revision 1, dated September 30, 1992. These 
service bulletins describe procedures for a test of the engine throttle 
quadrant to determine if the throttle lever bypasses the idle stop into 
the shut-off position, and modification of the throttle quadrant or 
replacement of the throttle quadrant with a modified unit. The 
modification involves removing material from the small triangular area 
on the outboard sides of both idle stop pawls to obtain specified 
protrusion dimensions or foot widths, testing each throttle lever to 
ensure it does not pass the idle stop into the shut-off position, and 
permanently reidentifying the unit. Transport Canada Aviation 
classified these service bulletins as mandatory and issued Canadian 
Airworthiness Directive CF-92-23, dated November 17, 1992, in order to 
assure the continued airworthiness of these airplanes in Canada. -
    The Canadair alert service bulletins discussed previously reference 
two service bulletins as additional sources of service information: 
Sargent Aerospace Service Bulletins 43058-76-03 (for Model CL-600-1A11 
series airplanes) and 43068-76-05 (for Model CL-600-2A12 and -2B16 
series airplanes), both dated April 13, 1992. -
    This airplane model is manufactured in Canada and is type 
certificated for operation in the United States under the provisions of 
Sec. 21.29 of the Federal Aviation Regulations and the applicable 
bilateral airworthiness agreement. Pursuant to this bilateral 
airworthiness agreement, Transport Canada Aviation has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of Transport Canada Aviation, 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. -
    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 a test of the 
engine throttle quadrant to determine if the throttle lever bypasses 
the idle stop into the shut-off position, and modification of the 
throttle quadrant or replacement of the throttle quadrant with a 
modified unit. The actions would be required to be accomplished in 
accordance with the Canadair alert service bulletins described 
previously. -
    The FAA estimates that 150 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 17 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $55 per work hour. Based on these figures, the 
total cost impact of the proposed AD on U.S. operators is estimated to 
be $140,250, or $935 per airplane. This total cost figure assumes that 
no operator has yet accomplished the proposed requirements of this AD 
action. -
    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 14 
CFR part 39 of the Federal Aviation Regulations as follows:

PART 39--[AMENDED]

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Canadair Limited: Docket 93-NM-207-AD.

    Applicability: Model CL-600-1A11 series airplanes, serial 
numbers 1004 through 1085 inclusive, equipped with Sargent throttle 
quadrants, part numbers 600-90601-69, -71, and -73; Model CL-600-
2A12 series airplanes, serial numbers 3001 through 3066 inclusive, 
equipped with Sargent throttle quadrants, part numbers 600-90601-
983, -1013, -1015, -1017, and -1019; and Model CL-600-2B16 series 
airplanes, serial numbers 5001 through 5114 inclusive, equipped with 
Sargent throttle quadrants, part numbers 600-90601-983, -1013, -
1015, -1017, and -1019; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent inadvertent shutdown of an engine while the airplane 
is taxiing or in flight, accomplish the following:
    (a) Within 50 hours time-in-service after the effective date of 
this AD, perform a test of the engine throttle quadrant to determine 
if the throttle lever bypasses the idle stop into the shut-off 
position, in accordance with Canadair Alert Service Bulletins A600-
0615, dated June 10, 1992 (for Model CL-600-1A11 series airplanes), 
or A601-0374, Revision 1, dated September 30, 1992 (for Model CL-
600-2A12 and -2B16 series airplanes), as applicable.

    Note 1: Canadair Alert Service Bulletins A600-0615 and A601-0374 
reference Sargent Aerospace Service Bulletins 43058-76-03 (for Model 
CL-600-1A11 series airplanes) and 43058-76-05 (for Model CL-600-2A12 
and -2B16 series airplanes), both dated April 13, 1992, for 
additional service information.

    (1) If the throttle lever bypasses the idle stop into the shut-
off position, prior to further flight, modify the throttle quadrant 
or replace the throttle quadrant with a modified unit, in accordance 
with the applicable service bulletin.
    (2) If the throttle lever does not bypass the idle stop into the 
shut-off position, within 600 landings after the effective date of 
this AD, modify the throttle quadrant or replace the throttle 
quadrant with a modified unit, in accordance with the applicable 
service bulletin.
    (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, New York Aircraft Certification 
Office (ACO), FAA, Engine and Propeller Directorate. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, New York ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York ACO.

    (c) Special flight permits may be issued in accordance with 
Federal Aviation Regulations (FAR) 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 February 3, 1994.
N.B. Martenson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-2914 Filed 2-8-94; 8:45 am]
BILLING CODE 4910-13-U