AD 2004-05-12

[Federal Register Volume 69, Number 47 (Wednesday, March 10, 2004)]
[Rules and Regulations]
[Pages 11293-11296]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 04-4683]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2004-NM-20-AD; Amendment 39-13507; AD 2004-05-12]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional 
Jet Series 100 & 440) Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to all Bombardier Model CL-600-2B19 (Regional Jet Series 
100 & 440) airplanes. This action requires repetitive inspections of 
the left and right engine throttle control gearboxes for wear, and 
corrective action if necessary. This action is necessary to prevent 
excessive wear of the gearboxes and subsequent movement or jamming of 
the engine throttle; movement of the throttle towards the idle position 
brings it close to the fuel shut-off switch, which could result in an 
in-flight engine shutdown. This action is intended to address the 
identified unsafe condition.

DATES: Effective March 25, 2004.
    The incorporation by reference of a certain publication listed in 
the regulations is approved by the Director of the Federal Register as 
of March 25, 2004.
    Comments for inclusion in the Rules Docket must be received on or 
before April 9, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2004-NM-20-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: 
<a href="/cdn-cgi/l/email-protection#043d29656a69296d6576676b6969616a70446265652a636b72"><span class="__cf_email__" data-cfemail="99a0b4f8f7f4b4f0f8ebfaf6f4f4fcf7edd9fff8f8b7fef6ef">[email&#160;protected]</span></a>. Comments sent via the Internet must contain 
``Docket No. 2004-NM-20-AD'' in the subject line and need not be 
submitted in triplicate. Comments sent via fax or the Internet as 
attached electronic files must be formatted in Microsoft Word 97 or 
2000 or ASCII text.
    The service information referenced in this AD may be obtained from 
Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station 
Centreville, Montreal, Quebec H3C 3G9, Canada. This information may be

[[Page 11294]]

examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, New York Aircraft Certification 
Office, 1600 Stewart Avenue, Westbury, New York; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: James Delisio, Aerospace Engineer, 
Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft 
Certification Office, 1600 Stewart Avenue, Westbury, New York 11581; 
telephone (516) 228-7321; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION: Transport Canada Civil Aviation (TCCA), 
which is the airworthiness authority for Canada, notified the FAA that 
an unsafe condition may exist on all Bombardier Model CL-600-2B19 
(Regional Jet Series 100 & 440) airplanes. TCCA advises that there have 
been numerous failures of the engine throttle control gearbox; some of 
the failures resulted in an in-flight engine shutdown. Investigation 
revealed that when the throttle is in the climb/cruise position, the 
rack teeth inside the gearbox can become worn down. Such excessive wear 
of the engine throttle gearbox can alter the rigging position or cause 
the throttle to jam. Movement of the throttle towards the idle position 
brings it close to the fuel shut-off switch, which can cause the engine 
to flame out. This condition, if not corrected, could result in an in-
flight engine shutdown.

Explanation of Relevant Service Information

    Bombardier has issued Service Bulletin 601R-76-019, dated August 
21, 2003, which describes procedures for inspections of the left and 
right engine throttle control gearboxes for certain wear values, and 
corrective action if necessary, as specified below:
    <bullet<ls-thn-eq> If the wear value is equal to or less than 0.006 
inch (0.152 mm) on both gearboxes, no corrective action is necessary.
    <bullet<ls-thn-eq> If the wear value is 0.010 inch (0.254 mm) or 
greater on one or both engine throttle gearboxes, the service bulletin 
describes procedures for replacing the affected gearbox with a new or 
serviceable gearbox before further flight.
    <bullet<ls-thn-eq> If the wear values are between 0.006 inch (0.152 
mm) and 0.010 inch (0.254 mm) on both engine throttle gearboxes, the 
service bulletin describes procedures for replacing the gearbox having 
the higher wear value with a new or serviceable gearbox before further 
flight, and replacing the gearbox having the lower wear value with a 
new or serviceable gearbox within the next 1,000 flight hours.
    <bullet<ls-thn-eq> If the wear values are between 0.006 inch (0.152 
mm) and 0.010 inch (0.254 mm), on one engine throttle gearbox only, and 
the wear value on the other gearbox is equal to or less than 0.006 inch 
(0.152mm), the service bulletin describes procedures for replacing the 
affected gearbox (having wear values between 0.006 inch and 0.010 inch) 
with a new or serviceable gearbox within the next 1,000 flight hours.
    All of the corrective actions specified above include rigging of 
the auto-throttle retarder control, and doing a functional test of the 
throttle system.
    The service bulletin also recommends that, during the inspection, 
operators make sure that the bolt and the two screws on the throttle 
control rod are correctly torqued to 20-25 lbf-in (2.25-2.82 N m). If 
the torque is not correct, the service bulletin specifies tightening to 
the correct torque and sending a report of the wear value on the 
gearbox to Bombardier. Accomplishment of the actions specified in the 
Bombardier service bulletin is intended to adequately address the 
identified unsafe condition.
    The Bombardier service bulletin references Trans Digm Inc., 
AeroControlex Group Service Bulletin 2100140-007-76-04, dated July 22, 
2003, as an additional source of service information for accomplishment 
of the inspections and replacement.
    TCCA classified the Bombardier service bulletin as mandatory and 
issued Canadian airworthiness directive CF-2004-01, dated January 21, 
2004, 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 
Sec.  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 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, this AD is being issued to prevent failure of the 
engine throttle control gearboxes, which could result in an in-flight 
engine shutdown. This AD requires repetitive inspections of the left 
and right engine throttle control gearboxes for wear, and corrective 
action if necessary. This AD also includes a reporting requirement. The 
actions are required to be accomplished in accordance with the service 
bulletin described previously, except as discussed below.
    This AD allows flight with wear on one engine throttle gearbox, 
provided that (1) the wear value meets the specifications in Part A, 
paragraph B.(7), of the Accomplishment Instructions of the Bombardier 
service bulletin, and (2) established inspection procedures detect wear 
values at intervals permitting replacement of the engine throttle 
control gearbox before the gearbox exceeds the acceptable wear value.

Differences Among Canadian Airworthiness Directive, Bombardier Service 
Bulletin, and This AD

    The Canadian airworthiness directive and the service bulletin 
specify the applicability as Model CL-600-2B19 airplanes with serial 
numbers 7003 through 7067 inclusive, and 7069 through 7999 inclusive. 
However, we have determined that all Model CL-600-2B19 may be subject 
to the identified unsafe condition; therefore, this AD is applicable to 
``All Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, 
certificated in any category.''
    Although the service bulletin recommends returning discrepant 
gearboxes to the parts manufacturer, this AD does not contain such a 
requirement.
    The Canadian airworthiness directive and the service bulletin do 
not define the type of inspection for wear of the engine throttle 
control gearboxes. We have clarified the inspection requirement 
contained in the AD as a detailed inspection. A note has been added to 
the AD to define that inspection.
    The Canadian airworthiness directive and the service bulletin 
recommend accomplishing the initial inspection of the engine throttle 
control gearboxes within 1,000 flight hours, but this AD requires 
accomplishment within 1,000 flight hours or 90 days, whichever is 
first. We find that a compliance time of 1,000 flight hours might not 
provide enough time to maintain an adequate level of safety for the 
affected fleet for those operators having airplanes with a

[[Page 11295]]

high number of flight hours every day. In developing an appropriate 
compliance time for this AD, we considered the degree of urgency 
associated with addressing the unsafe condition, and the maximum 
interval of time allowable for all affected airplanes to continue to 
operate without compromising safety. We find the specified compliance 
time to be appropriate for completing the initial inspection.

Interim Action

    This AD is considered to be interim action. The reports that are 
required by this AD will enable the manufacturer to obtain better 
insight into the nature, cause, and extent of the wear of the engine 
throttle control gearbox, and eventually to develop final action to 
address the unsafe condition. Once final action has been identified, we 
may consider further rulemaking.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Submit comments using the following format:
    <bullet<ls-thn-eq> 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.
    <bullet<ls-thn-eq> For each issue, state what specific change to 
the AD is being requested.
    <bullet<ls-thn-eq> 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 rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2004-NM-20-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein will 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 final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. Section 39.13 is amended by adding the following new airworthiness 
directive:

2004-05-12 Bombardier, Inc. (Formerly Canadair): Amendment 39-13507. 
Docket 2004-NM-20-AD.

    Applicability: All Model CL-600-2B19 (Regional Jet Series 100 & 
440) airplanes, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent excessive wear of the gearboxes and subsequent 
movement or jamming of the engine throttle; movement of the throttle 
towards the idle position brings it close to the fuel shut-off 
switch, which could result in an in-flight engine shutdown, 
accomplish the following:

Repetitive Inspections

    (a) Within 1,000 flight hours or 90 days after the effective 
date of this AD, whichever is first: Do a detailed inspection of the 
left and right engine throttle control gearboxes for wear by doing 
all the actions per Part A, paragraphs A., B., and C.(1) through 
C.(4), of the Accomplishment Instructions of Bombardier Service 
Bulletin 601R-76-019, dated August 21, 2003. If the wear value is 
the same as that specified in Part A, paragraph B.(8), of the 
Accomplishment Instructions of the service bulletin, repeat the 
inspection thereafter at intervals not to exceed 1,000 flight hours.

    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 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 the wear value found during any inspection required by 
paragraph (a) of this AD is not the same as that specified Part A, 
paragraph B.(8), of the Accomplishment Instructions of Bombardier 
Service Bulletin 601R-76-019, dated August 21, 2003: Do the 
applicable actions required by paragraph (b)(1), (b)(2), or (b)(3) 
of this AD, at the time specified, per the Accomplishment 
Instructions of the service bulletin. Repeat the inspection required 
by paragraph (a) of this AD thereafter at intervals not to exceed 
1,000 flight hours.
    (1) If the wear value on one or both of the gearboxes is the 
same as that specified in Part A, paragraph B.(5), of the 
Accomplishment Instructions of the service bulletin: Before further 
flight, replace the affected gearbox

[[Page 11296]]

with a new or serviceable gearbox, by doing all the actions per Part 
B, paragraphs D. through F.(7), of the Accomplishment Instructions 
of the service bulletin.
    (2) If the wear value on both the left and right gearboxes is 
the same as that specified in Part A, paragraph B.(6), of the 
Accomplishment Instructions of the service bulletin: Before further 
flight, replace the gearbox having the higher wear value with a new 
or serviceable gearbox, by doing all the actions per Part B, 
paragraphs D. through F.(7), of the Accomplishment Instructions of 
the service bulletin. Within 1,000 flight hours after doing the 
replacement, replace the other gearbox.
    (3) If the wear value on only one gearbox is the same as that 
specified in Part A, paragraph B.(7), and the wear value on the 
other gearbox is the same as that specified in Part A, paragraph 
B.(8), of the Accomplishment Instructions of the service bulletin: 
Within 1,000 flight hours after the inspection, replace the gearbox 
with the wear value that is the same as that specified in Part A, 
paragraph B.(7), with a new or serviceable gearbox. Do the 
replacement by doing all the actions per Part B, paragraphs D. 
through F.(7), of the Accomplishment Instructions of the service 
bulletin.

Additional Service Information

    Note 2: Bombardier Service Bulletin 601R-76-019, dated August 
21, 2003, references Trans Digm Inc., AeroControlex Group Service 
Bulletin 2100140-007-76-04, dated July 22, 2003, as an additional 
source of service information for accomplishment of the inspections 
and replacement.

Reporting Requirement

    (c) Within 10 days after accomplishment of the inspection 
required by paragraph (a) of this AD, or within 10 days after the 
effective date of this AD, whichever is later: Submit a report of 
gearbox wear to Bombardier Aerospace, as specified in Part A, 
paragraph B.(1), and Part B, paragraph E.(1) of the Accomplishment 
Instructions of Bombardier Service Bulletin 601R-76-019, dated 
August 21, 2003.

Alternative Methods of Compliance

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

Incorporation by Reference

    (e) The actions shall be done in accordance with Bombardier 
Service Bulletin 601R-76-019, dated August 21, 2003. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Bombardier, Inc., Canadair, 
Aerospace Group, P.O. Box 6087, Station Centreville, Montreal, 
Quebec H3C 3G9, Canada. Copies may be inspected at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, New York Aircraft Certification Office, 
1600 Stewart Avenue, Westbury, New York; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

    Note 3: The subject of this AD is addressed in Canadian 
airworthiness directive CF-2004-01, dated January 21, 2004.

Effective Date

    (f) This amendment becomes effective on March 25, 2004.

    Issued in Renton, Washington, on February 25, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-4683 Filed 3-9-04; 8:45 am]
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