[Federal Register Volume 72, Number 42 (Monday, March 5, 2007)]
[Rules and Regulations]
[Pages 9666-9674]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-3661]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-26378; Directorate Identifier 2006-NM-230-AD; 
Amendment 39-14972; AD 2007-05-11]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model CL-600-2B16 (CL-604) 
Airplanes and Model CL-600-2B19 (Regional Jet Series 100 & 440) 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is superseding two existing airworthiness directives 
(ADs), that apply to certain Bombardier Model CL-600-2B16 (CL-604) 
airplanes and Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes. These models may be referred to by their marketing 
designations as RJ100, RJ200, RJ440, CRJ100, CRJ200, CRJ440, and CL-65. 
One existing AD requires replacing the horizontal stabilizer trim 
control unit (HSTCU) with a new HSTCU. The other existing AD requires 
revising the airplane flight manual (AFM) to advise the flightcrew of 
procedures to follow in the event of stabilizer trim runaway, and in 
the event of MACH TRIM, STAB TRIM, and horizontal stabilizer trim 
malfunctions; and revising the AFM to require a review of the location 
of certain circuit breakers. That AD also requires doing a functional 
check of the stabilizer trim system and installing circuit breaker 
identification collars, and provides an optional terminating action. 
This new AD requires the previously optional terminating action and 
requires further revisions to the AFM. This AD also requires the 
removal of certain AFM revisions. This AD results from reports of trim 
problems including uncommanded trim, trim in the opposite direction to 
that selected, loss of trim position indication and, in one case, 
potential loss of trim disconnect capability. We are issuing this AD to 
prevent these events, which could result in conditions that vary from 
reduced controllability of the airplane to loss of control of the 
airplane.

DATES: This AD becomes effective March 20, 2007.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of March 20, 
2007.
    On November 14, 2006 (71 FR 63219, October 30, 2006), the Director 
of the Federal Register approved the incorporation by reference of 
certain other publications.
    On July 30, 1998 (63 FR 34574, June 25, 1998), the Director of the 
Federal Register approved the incorporation by reference of a certain 
other publication.
    We must receive any comments on this AD by April 4, 2007.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD.
    <bullet> DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
    <bullet> Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
    <bullet> Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
    <bullet> Fax: (202) 493-2251.
    <bullet> Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, 
Station Centre-ville, Montreal, Quebec H3C 3G9, Canada, for service 
information identified in this AD.
    You may examine the contents of the AD docket on the Internet at 
http://dms.dot.gov, or in person at the Docket Management Facility, 
U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-
401, on the plaza level of the Nassif Building, Washington, DC. This 
docket number is FAA-2006-26378; the directorate identifier for this 
docket is 2006-NM-230-AD.

FOR FURTHER INFORMATION CONTACT: Daniel Parrillo, Aerospace Engineer, 
Systems and Flight Test Branch, ANE-172, FAA, New York Aircraft 
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New 
York 11590; telephone (516) 228-7305; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

    On October 13, 2006, the FAA issued a supplemental notice of 
proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD 
that supersedes AD 2006-22-06, amendment 39-14803 (71 FR 63219, October 
30, 2006). The existing AD applies to certain Bombardier Model CL-600-
2B16 (CL-604) airplanes and Model CL-600-2B19 (Regional Jet Series 100 
& 440) airplanes. That supplemental NPRM was published in the Federal 
Register on December 28, 2006 (71 FR 78096). That supplemental NPRM 
proposed to retain the requirements of AD 2006-22-06 and to require the 
previously optional terminating action (installation of a new 
horizontal stabilizer trim control unit (HSTCU)). That supplemental 
NPRM also proposed to require, for certain airplanes, re-inserting the 
applicable temporary revisions of the Emergency and Abnormal Procedures 
sections of the airplane flight manual (AFM) under certain conditions.

Actions Since Supplemental NPRM Was Issued

    Since we issued that supplemental NPRM, Bombardier has issued new 
temporary revisions (TRs) to the AFMs as described in a comment 
submitted by the National Transportation Safety Board (NTSB) (see 
``Request to Revise AFM Procedures'' paragraph below). In the comment, 
the NTSB presents data to indicate that changes to the AFMs are 
necessary to address the identified unsafe condition. We have 
coordinated with Transport Canada Civil Aviation (TCCA) on this issue 
and concur that changes to the AFMs are necessary. In consideration of 
these new data, we have determined that the AFMs must be revised to 
include the new TRs within 14 days after the effective date of this AD.
    The FAA finds that, with respect to this additional requirement, 
since a situation exists that requires immediate adoption of this 
requirement, notice and time for prior public comment hereon are 
impracticable, and good cause exists for making this amendment 
effective in less than 30 days. Therefore, this AD will include the 
requirements specified in the supplemental NPRM (except the proposed 
requirement to re-insert TRs to the AFMs), as well as the certain new 
requirements discussed below. The new requirements include revising the 
AFMs to include the new TRs. In addition, we

[[Page 9667]]

are superseding AD 98-13-24, amendment 39-10615 (63 FR 34574, June 25, 
1998). See ``Request to Clarify Related AD'' paragraph below. This AD 
restates the requirement of AD 98-13-24 to install a certain HSTCU and 
specifies that doing the terminating action required by this new AD 
(installing a new HSTCU) terminates that earlier requirement.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments that have been 
received.

Request To Revise AFM Procedures

    The NTSB requests that we revise the AFM procedures specified in 
the supplemental NPRM. The NTSB notes that the supplemental NPRM states 
that AD 2006-22-06 requires and the supplemental NPRM proposes to 
require:
    <bullet> Revising the Emergency and Abnormal Procedures sections of 
the AFM to advise flight crews of procedures to follow in the event of 
MACH TRIM, STAB TRIM, and horizontal stabilizer trim malfunctions;
    <bullet> Revising the Normal section of the AFM to require a review 
of the location of certain circuit breakers and a functional check of 
the stabilizer trim system [required only by AD 2006-22-06]; and
    <bullet> Installing circuit breaker identification collars 
[required only by AD 2006-22-06].
    The NTSB summarizes the guidance provided to pilots in the revised 
Emergency Procedures section as follows:
    <bullet> Assume manual control of the control column and override 
the runaway.
    <bullet> Press, hold, and release the STAB TRIM disconnect switch.
    <bullet> If trim motion continues, pull the circuit breakers.
    Based on the examination of corroded motherboards and findings 
during the investigations of the three previous incidents, the NTSB 
believes that the revised AFM procedures should emphasize that, likely 
in all cases, an uncommanded movement of the horizontal stabilizer trim 
is a result of a short-circuit of the first officer's trim circuits. In 
addition, because the circuit breakers are accessible only to the first 
officer in Model CL-600-2B16 airplanes, the NTSB suggests that the 
Emergency Procedures be revised to indicate that control should be 
immediately transferred to the captain's controls to arrest the runaway 
trim with the captain's trim switch. Finally, because the only way to 
arrest a failure mode that occurred only with the trim channels 
disengaged was to pull the circuit breakers, the NTSB suggests that the 
procedures should emphasize pulling the circuit breakers if the trim 
channels are disengaged.
    We agree that the AFM should be revised. However, we disagree with 
the emphasis on trying to disengage the trim on the captain's side. We 
consider that it is possible to have contamination on the left- or 
right-hand side; therefore, both sides should attempt a disengagement.
    We agree that control must be transferred to the left-hand side to 
facilitate access to the circuit breakers on the right-hand side. 
However, we consider that the first priority, after regaining control 
by the pilot flying, is to disconnect the system using the disconnect 
switches, and that control be passed to the left-hand side subsequent 
to this step.
    We disagree with the suggestion to use the captain's trim switch to 
arrest the trim runaway. There have been cases identified of 
motherboard short circuits where operation of the trim switch would not 
arrest the runaway. Given the minimal time available to arrest a 
runaway, priority must be given to the most probable means of arresting 
the surface motion. These priorities are, first the control column 
disconnect switches, and second, the circuit breakers.
    We also disagree with depending on the Engaged/Disengaged trim 
channels annunciation to pull the circuit breakers. Instead, the AFM 
will be changed to remove such reference from the procedure and require 
that the circuit breakers be pulled in all cases.
    We agree to change the AFM procedure to reflect the changes below:
    <bullet> Control column--Assume manual control and override 
runaway.
    <bullet> Both STAB TRIM Disconnect switches--Press, hold and 
release.
    <bullet> Control--Transfer to pilot (LH) side.
    <bullet> STAB CH 1 and CH 2 HSTCU circuit breakers--Open.
    The above procedures will be included as memory/immediate action 
items.
    Bombardier has issued and we have reviewed the temporary revisions 
(TRs) specified in the table below.

                                                   Table--TRs
----------------------------------------------------------------------------------------------------------------
        For Bombardier Model--                  Use--                   Dated--                  To the--
----------------------------------------------------------------------------------------------------------------
CL-600-2B16 (CL-604) airplanes.......  Canadair Challenger TR   January 30, 2007.......  Canadair Challenger CL-
                                        604/21-2.                                         604 AFM, PSP 604-1.
CL-600-2B19 (Regional Jet Series 100   Canadair Regional Jet    January 26, 2007.......  Canadair Regional Jet
 & 440) airplanes.                      TR RJ/152-6.                                      AFM, CSP A-012.
----------------------------------------------------------------------------------------------------------------

    TR 604/21-2 supersedes Canadair Challenger TR 604/21-1, dated 
October 3, 2006, and TR RJ/152-6 supersedes Canadair Regional Jet TR 
RJ/152-5, dated October 3, 2006. Both TRs describe revising the 
Emergency and Abnormal Procedures sections of the applicable AFM to 
advise the flightcrew of additional procedures to follow in the event 
of stabilizer trim runaway and to advise the flightcrew of revised 
procedures to follow in the event of MACH TRIM, STAB TRIM, and 
horizontal stabilizer trim malfunctions.
    The new TRs must be inserted into the applicable AFM within 14 days 
after the effective date of this AD. We have determined that this 
revision is necessary to address uncommanded trim, trim in the opposite 
direction to that selected, loss of trim position indication and, in 
one case, potential loss of trim disconnect capability, which could 
result in conditions that vary from reduced controllability of the 
airplane to loss of control of the airplane. We have also determined 
that this revision provides a much more efficient procedure and a 
significant improvement for recovery from the stated unsafe condition. 
We have coordinated with TCCA on this issue. We have added paragraphs 
(m) and (n) of this AD accordingly to incorporate these AFM revisions.
    We have also removed the ``Reinsert AFM Revisions'' paragraph from 
this AD (paragraph (n) of the supplemental NPRM). Because this AD 
requires new AFM revisions, operators do not need to reinsert the old 
AFM revisions that may

[[Page 9668]]

have been removed in accordance with AD 2006-22-06.

Request To Clarify the Unsafe Condition

    The NTSB requests that we clarify the unsafe condition to state 
accurately the potential severity of uncommanded motion of the 
horizontal stabilizer trim on the affected airplanes. The NTSB states 
that the severity can range from major to catastrophic, based on the 
assessment of airplane performance under various runaway stabilizer 
trim conditions and the circumstances of the three recent reported 
incidents.
    The NTSB states that pilots from Bombardier Flight Test, TCCA, the 
FAA, and the NTSB have performed a comprehensive assessment of Model 
CL-600-2B16 and CL-600-2B19 airplane performance under various runaway 
stabilizer trim conditions using full flight simulators, desktop 
simulations, and test airplanes. The NTSB notes that the consensus from 
those efforts is that, depending on the nature of the runaway 
condition, the risk assessment can range from major to catastrophic.
    The NTSB also notes that the variables that affect the operational 
safety risk are the direction of the trim runaway, the ability to 
disconnect or override the trim, and whether the runaway is 
intermittent or constant. The NTSB states that the worst-case scenario 
(resulting in complete loss of airplane control) would be a constant 
trim runaway in the nose-up direction without the ability to disconnect 
or override the trim, and at the other end of the hazard assessment is 
an intermittent runaway trim in the nose-down direction with the 
ability to disconnect and override the trim. The NTSB has determined 
that the intermittent runaway trim scenario, if managed properly with 
no other extenuating circumstances, could be relatively benign; 
however, the NTSB explains that functional capabilities would still be 
reduced while crew workload and distress would increase, potentially 
affecting the crew's performance of other tasks. The NTSB concludes 
that this condition could end catastrophically if managed poorly or if 
other factors, such as weather, traffic, or other system failures, 
complicate operations.
    We agree to clarify the unsafe condition specified in this AD for 
the reasons provided by the NTSB. We have revised the unsafe condition 
in the Summary and paragraph (d) of this AD to read:

    This AD results from reports of trim problems including 
uncommanded trim, trim in the opposite direction to that selected, 
loss of trim position indication and, in one case, potential loss of 
trim disconnect capability. We are issuing this AD to prevent these 
events, which could result in conditions that vary from reduced 
controllability of the airplane to loss of control of the airplane.

Request To Clarify Related AD

    Comair also requests that we clarify whether this supplemental NPRM 
supersedes AD 98-13-24. Comair asks if the following requirement for 
certain airplanes in AD 98-13-24 also applies to the supplemental NPRM: 
``replace the HSTCU with a new HSTCU having part number 601R92301-9.'' 
Comair points out that AD 98-13-24 does not acknowledge replacing with 
a higher dash number (the supplemental NPRM specifies, and this new AD 
requires, replacement with a HSTCU having part number 601R92301-15 or 
higher dash number).
    We acknowledge the need to clarify how AD 98-13-24 relates to this 
AD. AD 98-13-24, which applies to Model CL-600-2B19 (Regional Jet 
Series 100 & 440) airplanes, serial numbers 7003 through 7112 
inclusive, requires the installation of the HSTCU, part number (P/N) 
601R92301-9, within 18 months after the effective date of that AD as a 
terminating action for other actions specified in that AD. Since AD 98-
13-24 became effective on July 30, 1998, all Model CL-600-2B19 
(Regional Jet Series 100 & 440) airplanes in the United States are 
required to be in compliance. If any airplane is imported, it must be 
in compliance with all applicable ADs, including AD 98-13-24.
    As this new AD requires the replacement of a part already cited in 
AD 98-13-24, we determined that this could lead to confusion regarding 
applicability and result in unnecessary record keeping. This new AD 
requires that the HSTCU be replaced with a higher part number (HSTCU P/
N 601R92301-15 or higher dash number).
    Therefore, we have determined that this AD should supersede AD 98-
13-24 as well as AD 2006-22-06 (the supplemental NPRM proposed to 
supersede AD 2006-22-06). We have revised paragraph (b) of this AD to 
read:
    ``This AD supersedes AD 98-13-24 and AD 2006-22-06.''
    We have also restated the requirements of paragraph (b) of AD 98-
13-24 as paragraph (f) of this AD. We have revised the remaining 
paragraph identifiers accordingly.
    All of the airplanes on the U.S. Register affected by AD 98-13-24 
are already in compliance with the actions required by AD 98-13-24; 
therefore, the requirements and costs to U.S. operators described in 
the supplemental NPRM will not change. We have determined that 
providing notice and opportunity for public comment on superseding AD 
98-13-24 is unnecessary before this AD is issued.

Requests To Extend Compliance Time

    The Regional Airline Association (RAA), on behalf of its members 
Air Wisconsin, Mesa Airlines, PSA Airlines, and Comair, requests that 
we extend the 9-month compliance time for the terminating action to 
read, ``within 12 months after the effective date of this AD.'' RAA 
notes that TCCA mandated a 12-month retrofit from the TCCA 
airworthiness directive's published date in October but the TCCA's 
airworthiness directive is applicable only to the relatively small 
fleet of Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes 
that operate in Canada. RAA recommends that we consult with Sagem (the 
parts manufacturer) to finalize our decision on a suitable compliance 
period and to consider that the airworthiness concern has never 
occurred within the regional fleet, and interim operational measures 
are currently in effect.
    Mesa Airlines states there have been no documented failures on the 
Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes and that 
the newly imposed circuit breaker identification and AFM revision will 
preclude an unlikely failure from becoming an incident. Mesa Airlines 
recommends that 6 months be added to the compliance time for these 
airplanes.
    Air Wisconsin concurs with the comments from Mesa Airlines. Air 
Wisconsin states that it doubts that the parts schedule will be able to 
be maintained and notes that an optimistic parts schedule issued by 
Bombardier will have the operator installing parts into October 2007. 
PSA Airlines agrees with Mesa Airlines and Air Wisconsin that the 9-
month compliance time is not realistic.
    Comair requests that we contact Bombardier and Sagem to determine 
if the schedule is realistic and will not place an undue burden on the 
operators. Comair notes that it has received units that failed prior to 
first flight and that these occurrences are not allotted for in the 
delivery schedule. Comair also states that it is nine units behind in 
receiving upgraded units based on the proposed shipping schedule.
    We disagree, because in developing an appropriate compliance time 
for this action, we considered the urgency associated with the subject 
unsafe condition, the availability of required

[[Page 9669]]

parts, and the practical aspect of accomplishing the required 
installation within a period of time that corresponds to the normal 
scheduled maintenance for most affected operators. According to 
Bombardier, enough required parts will be available to modify the U.S. 
fleet within the proposed compliance time. However, according to the 
provisions of paragraph (q) of this AD, we may approve requests to 
adjust the compliance time if the request includes data that prove that 
the new compliance time would provide an acceptable level of safety. We 
have not revised this AD in this regard.

Request To Reduce Compliance Time

    The NTSB requests that we reduce the 9-month compliance time to do 
the terminating action specified in supplemental NPRM. The NTSB is 
concerned that this compliance time may not sufficiently protect the 
fleet of affected airplanes from this hazardous condition. The NTSB 
notes that although the three previous in-flight incidents all involved 
Model CL-600-2B16 airplanes, a review of FAA service difficulty reports 
(SDR) for Bombardier CRJ 100/200 airplanes revealed more than 500 
anomalies with stabilizer trim in the last six years, including at 
least eight reports of uncommanded movement of the horizontal 
stabilizer that were reported in that time.
    The NTSB received statistics from the HSTCU manufacturer (Sagem 
Avionics, Inc.) that showed an average return rate of approximately 425 
HSTCUs per year with approximately 10 percent of HSTCU motherboards 
found to have some level of corrosion. The NTSB states that none of 
these boards had corrosion on the specific pins that control the 
captain's trim commands, which is significant because in the event of a 
trim runaway, a command from the captain's trim switch could override 
an uncommanded trim movement caused by the first officer's circuits.
    The NTSB states that various short-circuit scenarios were then 
extensively tested and that for every scenario tested (except for one), 
the captain's trim switch could be used to arrest or override a runaway 
trim. The NTSB notes that analysis of this condition to date suggests 
that any of the motherboards could be affected by corrosion and that 
corrosion can usually only be detected by disassembly of the HSTCU. The 
NTSB points out that HSTCUs with extensively corroded motherboards have 
passed built-in-test-equipment tests, as well as the manufacturer's 
acceptance test procedure, which could result in faulty HSTCUs not 
being removed from service. The NTSB adds that the boards examined were 
not cleaned sufficiently following the manufacturing process, which, in 
conjunction with sufficient moisture by condensation, could result in 
corrosion and pin-to-pin shorting and lead to trim runaway or several 
less significant anomalies. The NTSB states that the sampling of 
corroded boards would suggest that perhaps 50 airplanes are currently 
operating with contaminated motherboards, which, when coupled with 
sufficient moisture, will cause malfunctions. Data evaluated so far by 
NTSB investigators suggests that corrosion-induced runaway events occur 
randomly, independent of the age of the affected motherboard.
    The NTSB notes that a continuing airworthiness assessment performed 
by Bombardier estimated the probability of the corrosion failure mode 
causing uncommanded continuous trim movement at full speed of the 
horizontal stabilizer without disconnect capability to be 7.6 x 
10<SUP>-</SUP>\8\ per flight hour. However, the NTSB believes that, 
regardless of trim runaway direction or disconnect capability, any 
uncommanded runaway event presents the flight crew with a hazardous 
situation that, depending on other operational factors, may result in 
an accident. Accordingly, using the three in-flight incidents, the 
eight events from the SDR database, and the combined fleet history of 
13 million flight hours, the NTSB believes a more conservative estimate 
of incident probability is 8.5 x 10<SUP>-</SUP>\7\ per flight hour. The 
NTSB believes that this estimate may be optimistic considering it is 
likely that more of the SDRs were actually trim runaway events that 
were not correctly diagnosed. The NTSB states that data provided by 
Bombardier indicates that the average combined fleet utilization is 2.8 
million flight hours per year. The NTSB considers that the fleet may 
accumulate this number of flight hours over the AD compliance interval 
and therefore as many as two uncommanded runaway events could be 
expected to occur before the proposed AD is fully complied with. Even 
with this more conservative estimate, the NTSB notes that the three in-
flight events have occurred very recently in the fleet's 13-million-
flight-hour history, which suggests that some of the factors driving 
uncommanded trim events may not have been present or consistent over 
the entire history. Therefore, the NTSB concludes that the true 
probability of future events, in particular over the compliance period, 
is difficult to estimate accurately.
    The NTSB states that it is aware that Bombardier has been working 
with the HSTCU manufacturer to accelerate hardware production in 
regards to this AD. However, the NTSB is concerned that the FAA's 
proposed compliance time is formulated based on the quoted production 
rate and that uncertainty about the safety risk warrants priority 
consideration. Therefore, the NTSB strongly encourages the FAA to 
consider a shorter compliance time that provides reasonable assurance 
that the corrective action will be fully implemented without risking 
additional runaway events.
    We disagree with the request to reduce the compliance time because 
in developing an appropriate compliance time for this action, we 
considered the urgency associated with the subject unsafe condition, 
the availability of required parts, and the practical aspect of 
accomplishing the required installation within a period of time that 
corresponds to the normal scheduled maintenance for most affected 
operators. The FAA's and TCCA's harmonized position is that the stated 
compliance time of 9 months strikes the correct balance of risk 
mitigation. Bombardier has committed to the delivery of modified HSTCUs 
to meet this schedule. Any shortening of the compliance time may result 
in fleet groundings since there will not be sufficient modified HSTCUs 
available. However, as stated previously, we have revised the AFM 
procedures to provide a much more efficient procedure and a significant 
improvement for recovery from the stated unsafe condition.

Request To Remove First Flight of Day Functional Test

    Air Wisconsin requests that we remove the requirement for the 
airplane's first flight of the day functional test specified in the 
supplemental NPRM. The commenter states that the requirement was 
removed from the AFM at Revision 55 in July 2001 and therefore, there 
was no requirement to do this action for over 5 years until it was 
again required by AD 2006-22-06. The commenter notes that the 
terminating action in the supplemental NPRM allows operators to remove 
the temporary revision to abnormal procedures and the circuit breaker 
identification collars. The commenter concludes that the requirement 
for a daily functional test should be removed because the supplemental 
NPRM does not contain justification for retaining the test.
    We partially agree. We intended in AD 2006-22-06 for the first 
flight of the day check of the pitch trim disconnect switch to give 
crews a way to know daily that the disconnect switch is available and 
functional, because use of

[[Page 9670]]

the pitch trim disconnect can significantly mitigate the severity of 
uncommanded trim movement. Installing the modified HSTCUs required by 
this AD is terminating action for certain actions in AD 2006-22-06 and 
mitigates the higher risk of uncommanded movement. Therefore, the 
functional test is not necessary because the replacement has already 
mitigated the risks.
    We have revised this AD to remove the requirement for this 
functional test in the Model CL-600-2B19 (Regional Jet Series 100 & 
440) airplanes. Therefore, we have revised paragraph (o)(1) of this AD 
to require the removal of the AFM revisions required by paragraphs (j) 
and (k) of this AD after the installation required by paragraph (o) of 
this AD is done. Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes have had a history of pitch trim disconnect switch failures, 
which cause loss of both Channel 1 and 2 with resultant loss of pitch 
trim. We have been advised that exercising the switch increases wear 
and induces additional failures. That is the reason why this check was 
removed from the Canadair Regional Jet AFM at an earlier date. The Stab 
Trim System Reliability including switch reliability is covered in FAA 
Safety Recommendation 04.093. We have been strongly recommending a new 
switch, or a life limit on the existing switch, as well as other system 
improvements. Since Model CL-600-2B16 (CL-604) airplanes incur much 
less usage than Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes, switch wear is not considered a driver and hence the Stab 
Trim Check was recommended for the Model CL-600-2B16 (CL-604) 
airplanes.
    Also, since the Model CL-600-2B16 (CL-604) fleet already contains 
this functional test in its airplane flight manual, it will be 
recommended but not mandated that Model CL-604 crews continue to 
perform this functional test. Therefore, we have added a note after 
paragraph (o)(1) of this AD stating:

    It is recommended for Model CL-600-2B16 (CL-604) operators that 
the functional check of the stabilizer trim system on the aircraft's 
first flight of the day continue to be performed in accordance with 
the Normal Procedures Section of the Canadair Challenger CL-604 AFM.

Request for Alternative Method of Compliance

    Comair requests that we provide an alternative method of compliance 
for the actions specified in paragraph (l) of the supplemental NPRM. 
Comair notes that paragraph (l) specifies to do the installation, for 
certain airplanes, in accordance with Bombardier Service Bulletin 601R-
27-147, dated September 28, 2006, and paragraph B.(2) of the 
Accomplishment Instructions of the service bulletin specifies to do 
Sagem Service Bulletin HSTCU-27-011. Comair states that operators 
cannot ``do'' the Sagem service bulletin because units must be returned 
to Sagem for the upgrade. Comair states that this makes the 
installation a replacement of the HSTCU with the upgraded HSTCU. Comair 
states that the airplane maintenance manual (AMM) procedure for 
installation of the HSTCU, task 27-41-01-400-801, requires the same 
functional check and operational check called out in the referenced 
service bulletin. We infer that Comair requests that we refer to the 
AMM procedure as an alternative method of compliance.
    We disagree. Operators are not required to do the Sagem service 
bulletin. Paragraph (o) of this AD (paragraph (l) in the supplemental 
NPRM) requires installing the HSTCU P/N 601R92301-15 (Vendor P/N 7060-
10) or higher dash number in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletin 601R-27-147 (for Model CL-
600-2B19 (Regional Jet Series 100 & 440) airplanes). Although paragraph 
B.2 of the Accomplishment Instructions in Bombardier Service Bulletin 
601R-27-147 states ``Do the Avionics service bulletin HSTCU-27-011,'' 
this AD requires only that the HSTCU be installed and does not require 
operators to perform the actual modifications.
    In addition, we do not agree with referring to the AMM reference in 
this AD as a method of compliance for installing the modified HSTCU. 
The installation must be done in accordance with Bombardier Service 
Bulletin 601R-27-147. Bombardier Service Bulletin 601R-27-147 refers to 
the procedures in AMM 27-41-01-400-801 for the installation. Doing the 
procedures in any revision of the AMM is acceptable for complying with 
the installation requirements of this AD. In addition, according to the 
provisions of paragraph (q) of this AD, we may approve requests for 
alternative compliance methods if the request includes data that prove 
that the actions would provide an acceptable level of safety. We have 
not revised this AD in this regard.

Request To Revise Cost Paragraph

    RAA also request that we revise the cost of the installation. RAA 
states that one of its members pointed out that the cost to upgrade to 
a unit ``-10'' is $15,000.
    We do not agree to revise the cost of an upgrade to $15,000. 
Operators should note that when we calculate estimated costs, we do not 
consider job set up, close up, etc., to be part of the work hour 
calculation. Also, although the calculations in the supplemental NPRM 
used a figure of 11 work hours for installation, in fact, the only work 
hour numbers that should be used for the estimate should be 1 work hour 
for ``Procedure'' as specified in Bombardier Service Bulletin 601R-27-
147. For the parts costs, we referred to the ``Material Information'' 
section in Sagem Service Bulletin HSTCU-27-011, dated September 22, 
2006, which specifies a range from $0 to upgrade Sagem P/N 7060-9A that 
is under warranty up to $3,995 to upgrade a Sagem P/N 7060-8 or older 
version that is not under warranty. We have not revised this AD in this 
regard because the cost of compliance paragraph is not restated in this 
type of rulemaking action.

Request To Disallow Removal of Circuit Breaker Collars

    The Air Line Pilots Association (ALPA) requests that we disallow 
the removal of the circuit breaker identification collars that is 
allowed in paragraph (l) of the supplemental NPRM (paragraph (o) of 
this AD). ALPA states that procedures in place at several carriers rely 
on the crew's ability to readily identify the circuit breakers, and the 
existing circuit breaker collars facilitate that procedure. ALPA 
expects that even with the improvement represented by the supplemental 
NPRM, the procedures will continue to remain available to crews, so 
leaving the collars in place represents a safety benefit.
    We disagree because the wording in the AD allows for the removal of 
the collars but does not mandate the action. The circuit breaker 
collars were considered an interim action for quick identification in 
the case of runaway trim with an associated pitch trim system 
disconnect failure. The installation of the modified HSTCUs is 
considered terminating action for this risk. Therefore, we are not 
imposing the additional requirement for operators to maintain the 
circuit breaker collars after the installation has already mitigated 
the risks. We have not revised this AD in this regard.

Conclusion

    We have carefully reviewed the available data, including the 
comments that have been received, and determined that air safety and 
the public interest require adopting the AD with the changes described 
previously.

[[Page 9671]]

FAA's Determination and Requirements of This AD

    These airplanes 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 the FAA informed of 
the situation described above. We have examined TCCA's findings, 
evaluated all pertinent information, and determined that AD action is 
necessary for airplanes of this type design that are certificated for 
operation in the United States.
    Therefore, we are issuing this AD to supersede AD 2006-22-06 and AD 
98-13-24 and to continue to require the actions specified in those ADs. 
This AD also requires doing the terminating action (installation of a 
new HSTCU), and revising the Emergency and Abnormal Procedures sections 
of the AFM, which replace the existing revisions. This AD also requires 
the removal of certain AFM revisions.

Change to Supplemental NPRM

    As a result of superseding AD 98-13-24 and adding an action due to 
the new service information, we have changed certain paragraph 
identifiers and added others.

FAA's Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD; therefore, providing notice and opportunity for public comment 
before the AD is issued is impracticable, and good cause exists to make 
this AD effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements that affect 
flight safety and was not preceded by notice and an opportunity for 
public comment; however, we invite you to submit any relevant written 
data, views, or arguments regarding this AD. Send your comments to an 
address listed in the ADDRESSES section. Include ``Docket No. FAA-2006-
26378; Directorate Identifier 2006-NM-230-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the AD that might 
suggest a need to modify it.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this AD. Using the search function of that Web 
site, anyone can find and read the comments in any of our dockets, 
including the name of the individual who sent the comment (or signed 
the comment on behalf of an association, business, labor union, etc.). 
You can review the DOT's complete Privacy Act Statement in the Federal 
Register published on April 11, 2000 (65 FR 19477-78), or you can visit 
http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the Docket Management System 
receives them.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket. See the ADDRESSES 
section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA 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. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-10615 (63 FR 34574, June 25, 1998) and amendment 
39-14803 (71 FR 63219, October 30, 2006) and by adding the following 
new airworthiness directive (AD):

2007-05-11 Bombardier, Inc. (Formerly Canadair): Docket No. FAA 
2006-26378; Directorate Identifier 2006-NM-230-AD; Amendment 39-
14972.

Effective Date

    (a) This AD becomes effective March 20, 2007.

Affected ADs

    (b) This AD supersedes AD 98-13-24 and AD 2006-22-06.

Applicability

    (c) This AD applies to Bombardier Model CL-600-2B16 (CL-604) 
airplanes, serial numbers 5301 through 5665 inclusive; and Model CL-
600-2B19 (Regional Jet Series 100 & 440) airplanes, serial numbers 
7003 through 7990 inclusive and 8000 through 8066 inclusive; 
certificated in any category.

    Note 1: The Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes may be referred to by their marketing designations as 
RJ100, RJ200, RJ440, CRJ100, CRJ200, CRJ440, and CL-65.

Unsafe Condition

    (d) This AD results from reports of trim problems including 
uncommanded trim, trim

[[Page 9672]]

in the opposite direction to that selected, loss of trim position 
indication and, in one case, potential loss of trim disconnect 
capability. We are issuing this AD to prevent these events, which 
could result in conditions that vary from reduced controllability of 
the airplane to loss of control of the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Restatement of Certain Requirements of AD 98-13-24

Replacement of Horizontal Stabilizer Trim Control Unit (HSTCU)

    (f) For Model CL-600-2B19 (Regional Jet Series 100) airplanes, 
serial numbers 7003 through 7112 inclusive: Within 18 months after 
July 30, 1998 (the effective date of AD 98-13-24), replace the HSTCU 
with a new HSTCU having part number 601R92301-9, and reactivate the 
mach trim switch/light (if deactivated), in accordance with 
Bombardier Service Bulletin S.B. 601R-27-053, Revision B, dated 
February 21, 1997. Doing paragraph (o) of this AD terminates the 
requirements of this paragraph.

    Note 2: Accomplishment of paragraph (f) of this AD, prior to 
July 30, 1998, in accordance with Bombardier Service Bulletin S.B. 
601R-27-053, dated May 27, 1996; or Revision A, dated August 26, 
1996; is considered acceptable for compliance with the applicable 
actions specified in paragraph (f) of this AD.

Restatement of Certain Requirements of AD 2006-22-06

Airplane Flight Manual (AFM) Revisions

    (g) Within 14 days after November 14, 2006 (the effective date 
of AD 2006-22-06), make the applicable AFM revisions specified in 
paragraph (g)(1) or (g)(2) of this AD by incorporating the 
applicable Canadair (Bombardier) temporary revisions (TRs) 
identified in Table 1 of this AD into the applicable AFM. Doing the 
revision specified in paragraph (m) of this AD terminates the 
requirements of this paragraph for those airplanes only.
    (1) For Model CL-600-2B16 (CL-604) airplanes: Revise the 
Emergency and Abnormal Procedures sections of the AFM to advise the 
flightcrew of additional procedures to follow in the event of 
stabilizer trim runaway and to advise the flightcrew of revised 
procedures to follow in the event of MACH TRIM, STAB TRIM, and 
horizontal stabilizer trim malfunctions.
    (2) For Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes: Revise the Emergency and Abnormal Procedures sections of 
the AFM to advise the flightcrew of revised procedures to follow in 
the event of stabilizer trim runaway and in the event of MACH TRIM, 
STAB TRIM, and horizontal stabilizer trim malfunctions.

                                                  Table 1--TRs
----------------------------------------------------------------------------------------------------------------
        For Bombardier Model--                  Use--                   Dated--                  To the--
----------------------------------------------------------------------------------------------------------------
CL-600-2B16 (CL-604) airplanes.......  Canadair Challenger TR   October 3, 2006........  Canadair Challenger CL-
                                        604/21-1.                                         604 AFM, PSP 604-1.
CL-600-2B19 (Regional Jet Series 100   Canadair Regional Jet    October 3, 2006........  Canadair Regional Jet
 & 440) airplanes.                      TR RJ/152-5.                                      AFM, CSP A-012.
----------------------------------------------------------------------------------------------------------------

    (h) When the applicable TR specified in paragraph (g) of this AD 
has been included in the general revisions of the applicable AFM, 
those general revisions may be inserted into the AFM and the 
applicable TR may be removed, provided the relevant information in 
the general revisions is identical to that in the TR.

Installation of Circuit Breaker Identification Collars

    (i) Within 14 days after November 14, 2006, install circuit 
breaker identification collars in accordance with Bombardier 
Modification Summary Package IS601R27410051, Revision C, dated 
September 29, 2006 (for Model CL-600-2B19 (Regional Jet Series 100 & 
440) airplanes); or the Accomplishment Instructions of Bombardier 
Alert Service Bulletin A604-27-029, dated September 28, 2006 (for 
Model CL-600-2B16 (CL-604) airplanes); as applicable.

Additional AFM Revision

    (j) For Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes: Within 14 days after November 14, 2006, revise the Normal 
section of the Canadair Regional Jet AFM, CSP A-012, to include the 
statement specified in Figure 1 of this AD. This may be done by 
inserting a copy of Figure 1 of this AD into the AFM.
    ``Prior to the flightcrew's first flight of the day, do the 
following actions:
    1. Review the location of the STAB CH1 HSTCU and STAB CH2 HSTCU 
circuit breakers.
    2. Complete a functional check of the stabilizer trim system as 
detailed below.

                Control Wheel Stab Trim Disconnect Check
 
Control Wheel Stab Trim Disconnect   <bullet> Make sure STAB TRIM
 switches . . . . Check               caution message is out.
                                     <bullet> Activate the pilot's
                                      Control Wheel Stab Trim Disconnect
                                      switch and make sure the STAB TRIM
                                      caution message comes on.
               NOTE:                 <bullet> Engage the STAB TRIM
During ground testing only, do not    switches and make sure the STAB
 activate the Control Wheel Stab      TRIM caution message is out.
 Trim Disconnect switch if the       <bullet> Activate the co-pilot's
 horizontal stabilizer trim is in     Control Wheel Stab Trim Disconnect
 motion.                              switch and make sure the STAB TRIM
                                      caution message comes on.
                                     <bullet> Engage the STAB TRIM and
                                      MACH TRIM switches and make sure
                                      the STAB TRIM and MACH TRIM
                                      caution messages are out.''
 
                                Figure 1
 


    Note 3: When a statement identical to that in paragraph (j) of 
this AD has been included in the general revisions of the applicable 
AFM, those general revisions may be inserted into the AFM, and the 
copy of this AD may be removed from the AFM.

    (k) For Model CL-600-2B16 (CL-604) airplanes: Within 14 days 
after November 14, 2006, revise the Normal section of the Canadair 
Challenger CL-604 AFM, PSP 604-1, to include the following 
statement. This may be done by inserting a copy of this AD into the 
AFM.
    ``Prior to the flightcrew's first flight of the day, do the 
following actions:
    1. Review the location of the STAB CH1 HSTCU and STAB CH2 HSTCU 
circuit breakers.
    2. Check the stabilizer trim system as detailed in CL-604 AFM 
`Normal Procedures' section titled `Flight Controls Trim Systems, 
Before Flight--First Flight of the Day.' ''

    Note 4: When a statement identical to that in paragraph (k) of 
this AD has been included in the general revisions of the applicable 
AFM, those general revisions may be inserted into the AFM, and the 
copy of this AD may be removed from the AFM.

Previous Actions Accomplished According to Modification Summary 
Package

    (l) Actions accomplished before November 14, 2006, in accordance 
with Bombardier Modification Summary Package

[[Page 9673]]

IS601R27410051, Revision A, dated September 18, 2006; or Revision B, 
dated September 27, 2006; are considered acceptable for compliance 
with the action specified in paragraph (i) of this AD, provided that 
the circuit breaker collars meet the color requirements of 
Bombardier Modification Summary Package IS601R27410051, Revision C, 
dated September 29, 2006.

New Requirements of This AD

New Revised AFM Revisions

    (m) Within 14 days after the effective date of this AD, make the 
applicable AFM revisions specified in paragraph (m)(1) or (m)(2) of 
this AD by incorporating the applicable Canadair (Bombardier) TRs 
identified in Table 2 of this AD into the applicable AFM, and after 
doing the revision, remove the applicable AFM revision required by 
paragraph (g) of this AD from the applicable AFM. Doing the 
applicable revision specified in this paragraph terminates the 
requirements of paragraph (g) for that airplane.
    (1) For Model CL-600-2B16 (CL-604) airplanes: Revise the 
Emergency and Abnormal Procedures sections of the AFM to advise the 
flightcrew of procedures to follow in the event of stabilizer trim 
runaway and in the event of MACH TRIM, STAB TRIM, and horizontal 
stabilizer trim malfunctions.
    (2) For Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes: Revise the Emergency and Abnormal Procedures sections of 
the AFM to advise the flightcrew of revised procedures to follow in 
the event of stabilizer trim runaway and in the event of MACH TRIM, 
STAB TRIM, and horizontal stabilizer trim malfunctions.

                                              Table 2.--Revised TRs
----------------------------------------------------------------------------------------------------------------
        For Bombardier Model--                  Use--                   Dated--                  To the--
----------------------------------------------------------------------------------------------------------------
CL-600-2B16 (CL-604) airplanes.......  Canadair Challenger TR   January 30, 2007.......  Canadair Challenger CL-
                                        604/21-2.                                         604 AFM, PSP 604-1.
CL-600-2B19 (Regional Jet Series 100   Canadair Regional Jet    January 26, 2007.......  Canadair Regional Jet
 & 440) airplanes.                      TR RJ/152-6.                                      AFM, CSP A-012.
----------------------------------------------------------------------------------------------------------------

    (n) When the applicable TR specified in paragraph (m) of this AD 
has been included in the general revisions of the applicable AFM, 
those general revisions may be inserted into the AFM and the 
applicable TR may be removed.

Terminating Action--Installation of New, Improved Part

    (o) Within 9 months after the effective date of this AD, install 
HSTCU, part number (P/N) 601R92301-15 (vendor P/N 7060-10) or higher 
dash number, in accordance with the Accomplishment Instructions of 
Bombardier Alert Service Bulletin A604-27-029, dated September 28, 
2006 (for Model CL-600-2B16 (CL-604) airplanes); or Bombardier 
Service Bulletin 601R-27-147, dated September 28, 2006 (for Model 
CL-600-2B19 (Regional Jet Series 100 & 440) airplanes); as 
applicable. Doing this installation terminates the requirements of 
paragraph (f) of this AD. After doing this installation, the circuit 
breaker identification collars required by paragraph (i) of this AD 
may be removed. After doing this installation, the requirements 
specified in paragraphs (o)(1) and (o)(2) of this AD must be 
followed.
    (1) Within 14 days after doing the installation or within 14 
days after the effective date of this AD, whichever occurs later, 
the AFM revisions required by paragraphs (j) and (k) of this AD must 
be removed from the AFM.

    Note 5: It is recommended for Model CL-600-2B16 (CL-604) 
operators that the functional check of the stabilizer trim system on 
the aircraft's first flight of the day continue to be performed in 
accordance with the Normal Procedures Section of the Canadair 
Challenger CL-604 AFM.

    (2) After doing the installation, the AFM revisions required by 
paragraph (g) of this AD may be removed from the applicable AFM, but 
only if the removal of the AFM revisions was done before the 
effective date of this AD.

    Note 6: Bombardier Service Bulletin 601R-27-147, dated September 
28, 2006, refers to Sagem Service Bulletin HSTCU-27-011, dated 
September 22, 2006, as an additional source of service information 
for accomplishment of the installation.

Service Bulletin Exception

    (p) Although Bombardier Alert Service Bulletin A604-27-029, 
dated September 28, 2006, specifies to return certain parts to the 
manufacturer, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

    (q)(1) The Manager, New York Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Related Information

    (r) Canadian airworthiness directives CF-2006-20R1, dated 
October 4, 2006, and CF-2006-21R1, dated October 3, 2006, also 
address the subject of this AD.

Material Incorporated by Reference

    (s) You must use Bombardier Modification Summary Package 
IS601R27410051, Revision C, dated September 29, 2006; the service 
bulletins listed in Table 3 of this AD; and the temporary revisions 
listed in Table 4 of this AD; as applicable, to perform the actions 
that are required by this AD, unless the AD specifies otherwise.

          Table 3.--Service Bulletins Incorporated by Reference
------------------------------------------------------------------------
       Service bulletin             Revision level             Date
------------------------------------------------------------------------
Bombardier Alert Service       Original................  September 28,
 Bulletin A604-27-029.                                    2006.
Bombardier Service Bulletin    B.......................  February 21,
 S.B. 601R-27-053.                                        1997.
Bombardier Service Bulletin    Original................  September 28,
 601R-27-147.                                             2006.
------------------------------------------------------------------------


       Table 4.--All Temporary Revisions Incorporated by Reference
------------------------------------------------------------------------
     Temporary revision--               Dated--              To the--
------------------------------------------------------------------------
Canadair Challenger Temporary  October 3, 2006.........  Canadair
 Revision 604/21-1.                                       Challenger CL-
                                                          604 Airplane
                                                          Flight Manual,
                                                          PSP 604-1.
Canadair Challenger Temporary  January 30, 2007........  Canadair
 Revision 604/21-2.                                       Challenger CL-
                                                          604 Airplane
                                                          Flight Manual,
                                                          PSP 604-1.

[[Page 9674]]

 
Canadair Regional Jet          October 3, 2006.........  Canadair
 Temporary Revision RJ/152-5.                             Regional Jet
                                                          Airplane
                                                          Flight Manual,
                                                          CSP A-012.
Canadair Regional Jet          January 26, 2007........  Canadair
 Temporary Revision RJ/152-6.                             Regional Jet
                                                          Airplane
                                                          Flight Manual,
                                                          CSP A-012.
------------------------------------------------------------------------

    (1) The Director of the Federal Register approved the 
incorporation by reference of the temporary revisions listed in 
Table 5 of this AD in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51.

       Table 5.--New Temporary Revisions Incorporated by Reference
------------------------------------------------------------------------
     Temporary revision--               Dated--              To the--
------------------------------------------------------------------------
Canadair Challenger Temporary  January 30, 2007........  Canadair
 Revision 604/21-2.                                       Challenger CL-
                                                          604 Airplane
                                                          Flight Manual,
                                                          PSP 604-1.
Canadair Regional Jet          January 26, 2007........  Canadair
 Temporary Revision RJ/152-6.                             Regional Jet
                                                          Airplane
                                                          Flight Manual,
                                                          CSP A-012.
------------------------------------------------------------------------

    (2) On November 14, 2006 (71 FR 63219, October 30, 2006), the 
Director of the Federal Register approved the incorporation by 
reference of Bombardier Alert Service Bulletin A604-27-029, dated 
September 28, 2006; Bombardier Service Bulletin 601R-27-147, dated 
September 28, 2006; Bombardier Modification Summary Package 
IS601R27410051, Revision C, dated September 29, 2006; and the 
temporary revisions listed in Table 6 of this AD in accordance with 
5 U.S.C. 552(a) and 1 CFR part 51.

    Table 6.--Previous Temporary Revisions Incorporated by Reference
------------------------------------------------------------------------
     Temporary revision--               Dated--              To the--
------------------------------------------------------------------------
Canadair Challenger Temporary  October 3, 2006.........  Canadair
 Revision 604/21-1.                                       Challenger CL-
                                                          604 Airplane
                                                          Flight Manual,
                                                          PSP 604-1.
Canadair Regional Jet          October 3, 2006.........  Canadair
 Temporary Revision RJ/152-5.                             Regional Jet
                                                          Airplane
                                                          Flight Manual,
                                                          CSP A-012.
------------------------------------------------------------------------

    (3) On July 30, 1998 (63 FR 34574, June 25, 1998), the Director 
of the Federal Register approved the incorporation by reference of 
Bombardier Service Bulletin S.B. 601R-27-053, Revision B, dated 
February 21, 1997; in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51.
    (4) Contact Bombardier, Inc., Canadair, Aerospace Group, P.O. 
Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada, 
for a copy of this service information. You may review copies at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on February 21, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-3661 Filed 3-2-07; 8:45 am]
BILLING CODE 4910-13-P