Document ID: FAA-2008-0555-0004
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; Bombardier Model CL-600-2C10 (Regional Jet Series 700 and 701) Series Airplanes and Model CL-600-2D24 (Regional Jet Series 900) Series Airplanes
Posted Date: 2008-10-29T04:00Z

[Federal Register: October 29, 2008 (Volume 73, Number 210)]
[Rules and Regulations]               
[Page 64191-64194]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29oc08-3]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0555; Directorate Identifier 2008-NM-074-AD; 
Amendment 39-15705; AD 2005-13-02 R1]
RIN 2120-AA64

 
Airworthiness Directives; Bombardier Model CL-600-2C10 (Regional 
Jet Series 700 & 701) Series Airplanes and Model CL-600-2D24 (Regional 
Jet Series 900) Series Airplanes

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

ACTION: Final rule.

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SUMMARY: The FAA is revising an existing airworthiness directive (AD) 
that applies to certain Bombardier Model CL-600-2C10 (Regional Jet 
series 700 & 701) series airplanes and Model CL-600-2D24 (Regional Jet 
series 900) series airplanes. That AD currently requires revising the 
Airworthiness Limitations section of the Instructions of Continued 
Airworthiness by incorporating new repetitive inspections and an 
optional terminating action for the repetitive inspections, and 
repairing any crack. This new AD clarifies the applicability of the 
existing AD. This AD results from reports of hydraulic pressure loss in 
either the number 1 or number 2 hydraulic system due to breakage or 
leakage of hydraulic lines in the aft equipment bay and reports of 
cracks on the aft pressure bulkhead web around the feed-through holes. 
We are issuing this AD to prevent loss of hydraulic pressure, which 
could result in reduced controllability of the airplane, and to detect 
and correct cracks on the aft pressure bulkhead web, which could result 
in reduced structural integrity of the aft pressure bulkhead.

DATES: This AD is effective December 3, 2008.
    On July 27, 2005 (70 FR 35987, June 22, 2005), the Director of the 
Federal Register approved the incorporation by reference of Bombardier 
CRJ 700/900 Series Temporary Revision MRM2-129, dated June 1, 2004.

ADDRESSES: For service information identified in this AD, contact 
Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station 
Centre-ville, Montreal, Quebec H3C 3G9, Canada.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (telephone 800-647-5527) is the Document Management 
Facility, U.S. Department of Transportation, Docket Operations, M-30, 
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Pong Lee, Aerospace Engineer, Airframe 
and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification 
Office, 1600 Stewart Avenue, Suite 410,

[[Page 64192]]

Westbury, New York 11590; telephone (516) 228-7324; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA proposed to amend part 39 of the Federal Aviation 
Regulations (14 CFR part 39) with an airworthiness directive (AD) to 
revise AD 2005-13-02, amendment 39-14138 (70 FR 35987, June 22, 2005). 
The existing AD applies to certain Bombardier Model CL-600-2C10 
(Regional Jet series 700 & 701) series airplanes and Model CL-600-2D24 
(Regional Jet series 900) series airplanes. The proposed AD was 
published in the Federal Register on May 19, 2008 (73 FR 28754) to 
continue to revise the Airworthiness Limitations section of the 
Instructions of Continued Airworthiness by incorporating new repetitive 
inspections and an optional terminating action for the repetitive 
inspections, and repairing any crack. The proposed AD also clarifies 
the applicability of the existing AD.

Comments

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

Request To Withdraw NPRM

    Comair requests that the NPRM be withdrawn. Comair states that the 
minor editorial correction to the Applicability section of the NPRM 
should not warrant a revised or new directive, and that the revised AD 
will not increase the airworthiness of any airplane. Comair also states 
that a review of the airplane log will indicate which service bulletins 
have been incorporated by Bombardier, on a limited basis, before 
delivery to a customer.
    We do not agree with Comair to withdraw the NPRM. When a previously 
issued AD is changed, we issue a correction, revision, or supersedure 
AD, depending on the nature of the material being changed. In the case 
of this AD, a revision AD is the appropriate means to clarify the 
Applicability section of AD 2005-13-02. We have determined that 
issuance of this AD is necessary because Bombardier does not 
incorporate service bulletins in production and operators may 
misinterpret which affected airplanes are subject to the requirements 
of this AD.

Requests To Revise the Applicability Section

    Comair notes that Bombardier Service Bulletin 670BA-29-008 is 
currently at Revision B, dated August 28, 2007. Paragraph (c) of the 
NPRM (i.e., Applicability section) refers to the initial issue, dated 
March 12, 2004; and Revision A, dated May 5, 2004; of that service 
bulletin.
    From this comment, we infer that Comair is requesting that 
paragraph (c) of the NPRM be revised to also exclude those airplanes on 
which Revision B of Bombardier Service Bulletin 670BA-29-008 has been 
incorporated. We agree and revised paragraph (c) of this AD 
accordingly.
    Comair requests that the serial numbers for Model CL-600-2C10 
series airplanes identified in Table 1 of the NPRM be limited to serial 
numbers 10003 through 10156 inclusive. Comair states that comments were 
submitted to the NPRM for AD 2005-13-02 to limit the serial number 
range for which that AD should apply. In the preamble of the final rule 
for AD 2005-13-02, Comair notes that the FAA agreed with that comment 
but believes that we made a mistake by not revising the serial numbers 
in Table 1 of that AD (which is retained in the NPRM). Although not 
addressed in its NPRM comment for AD 2005-13-02, Comair also requests 
that, for the reason discussed previously, Table 1 of the NPRM be 
limited to serial numbers 15001 through 15026 inclusive for Model CL-
600-2D24 series airplanes. Comair states that it does not make sense to 
issue an AD against airplane serial numbers for which there is no 
action required.
    We do not agree with Comair's request to revise Table 1 of this AD. 
As stated in the preamble of AD 2005-13-02, we revised the 
applicability of that AD to exclude those airplanes on which certain 
modification summaries and service information had been incorporated. 
This approach rather than changing the reference to certain serial 
numbers, accomplishes the same intent. The referenced modification 
summaries and service information in this AD (i.e., Modification 
Summaries 670T00494 or 670T11944; Modification Summary 670T11508; and 
Bombardier Service Bulletin 670BA-29-008, dated March 12, 2004, 
Revision A, dated May 5, 2004, or Revision B, dated August 28, 2007) 
identify the serial numbers of those airplanes. Therefore, we find no 
change to this AD is necessary in this regard.

Request To Revise Costs of Compliance Section

    Comair requests that the number of U.S.-registered airplanes 
specified in the Costs of Compliance section of the NPRM be changed 
from 116 to 255. Comair states that the Costs of Compliance section 
takes into account that either only airplanes with serial numbers below 
10157 and 15027 are affected by this AD or the number needs to be 
adjusted to today's U.S. registry level. Comair states that a 
conversation with a Bombardier Field Service Representative indicates 
that all affected serial numbers have had the modification summaries 
and/or service bulletin specified in paragraph (c) of the NPRM 
incorporated and thus the NPRM does not apply to any U.S registered 
airplanes.
    We agree with Comair to revise the Costs of Compliance section of 
this AD to reflect the current number of affected airplanes on the U.S. 
registry (i.e., 324 airplanes). We consulted with Bombardier and 
confirmed that all affected Bombardier Model CL-600-2C10 (Regional Jet 
series 700 & 701) series airplanes and Model CL-600-2D24 (Regional Jet 
series 900) series airplanes have been modified according to the 
optional terminating action specified in this AD. Therefore, currently, 
this AD imposes no additional financial burden on any U.S. operator. We 
have also revised the Costs of Compliance section of this AD in this 
regard.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    This AD affects about 324 airplanes of U.S. registry. We have been 
advised that all affected Bombardier Model CL-600-2C10 (Regional Jet 
series 700 & 701) series airplanes and Model CL-600-2D24 (Regional Jet 
series 900) series airplanes on the U.S. Register have been modified 
according to the optional terminating action specified in this AD. 
Therefore, currently, this AD imposes no additional financial burden on 
any U.S. operator.
    However, if an unmodified airplane is imported and placed on the 
U.S. Register in the future, the actions required by this AD would take 
about 1 work hour per airplane, at an average labor rate of $80 per 
work hour. Based on these figures, we estimate the cost of this AD to 
be $80 per airplane.

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

[[Page 64193]]

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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under 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 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 39-14138 (70 FR 35987, June 22, 2005) and adding the 
following new airworthiness directive (AD):

2005-13-02 Bombardier, Inc. (Formerly Canadair): Amendment 39-15705. 
Docket No. FAA-2008-0555; Directorate Identifier 2008-NM-074-AD.

Effective Date

    (a) This airworthiness directive (AD) is effective December 3, 
2008.

Affected ADs

    (b) This AD revises AD 2005-13-02.

Applicability

    (c) This AD applies to the airplanes listed in Table 1 of this 
AD, certificated in any category, excluding those airplanes on which 
Modification Summary 670T00494 or 670T11944; and Modification 
Summary 670T11508 or Bombardier Service Bulletin 670BA-29-008, dated 
March 12, 2004, Revision A, dated May 5, 2004, or Revision B, dated 
August 28, 2007; has been incorporated.

                         Table 1--Applicability
------------------------------------------------------------------------
       Bombardier model                        Serial No.
------------------------------------------------------------------------
 (1) CL-600-2C10 (Regional Jet   10003 through 10999 inclusive.
 Series 700 & 701) series
 airplanes.
 (2) CL-600-2D24 (Regional Jet   15001 through 15990 inclusive.
 Series 900) series airplanes.
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD resulted from reports of hydraulic pressure loss in 
either the number 1 or number 2 hydraulic system due to breakage or 
leakage of hydraulic lines in the aft equipment bay and reports of 
cracks on the aft pressure bulkhead web around the feed-through 
holes. We are issuing this AD to prevent loss of hydraulic pressure, 
which could result in reduced controllability of the airplane, and 
to detect and correct cracks on the aft pressure bulkhead web, which 
could result in reduced structural integrity of the aft pressure 
bulkhead.

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 Requirements of AD 2005-13-02

Revision of Airworthiness Limitations Section

    (f) Within 30 days after July 27, 2005 (the effective date of AD 
2005-13-02), revise the Airworthiness Limitations section of the 
Instructions of Continued Airworthiness by inserting a copy of the 
new repetitive inspections and an optional terminating action of 
Bombardier CRJ 700/900 Series Temporary Revision (TR) MRM2-129, 
dated June 1, 2004, into section 1.4, Part 2 (Airworthiness 
Limitations), of Bombardier Regional Jet Model CL-600-2C10 and CL-
600-2D24 Maintenance Requirements Manual, CSP B-053. Thereafter, 
except as provided in paragraph (h)(2) or (i) of this AD, no 
alternative structural inspection intervals may be approved for this 
aft pressure bulkhead and pylon pressure pan in the vicinity of the 
hydraulic fittings and the hydraulic tube adapters.
    (g) When the information in TR MRM2-129, dated June 1, 2004, is 
included in the general revisions of the Maintenance Requirement 
Manual, the general revisions may be inserted into the Airworthiness 
Limitations section of the Instructions of Continued Airworthiness 
and this TR may be removed.

Corrective Action

    (h) If any crack is found during any inspection done in 
accordance with Bombardier CRJ 700/900 Series TR MRM2-129, dated 
June 1, 2004, or the same inspection specified in the general 
revisions of the Maintenance Requirement Manual, do the actions 
specified in paragraphs (h)(1) and (h)(2) of this AD.
    (1) Before further flight, repair the crack in accordance with a 
method approved by either the Manager, New York Aircraft 
Certification Office (ACO), FAA; or Transport Canada Civil Aviation 
(TCCA) (or its delegated agent).
    (2) At the applicable time specified in paragraph (h)(2)(i) or 
(h)(2)(ii) of this AD, revise the Airworthiness Limitations section 
of the Instructions of Continued Airworthiness by inserting a copy 
of the inspection requirements for the repair required by paragraph 
(h)(1) of this AD into Section 1.4, Part 2 (Airworthiness 
Limitations), of Bombardier Regional Jet Model CL-600-2C10 and CL-
600-2D24 Maintenance Requirements Manual, CSP B-053. Thereafter, 
except as provided in paragraph (i) of this AD, no alternative 
structural inspection intervals may be approved for this aft 
pressure bulkhead and pylon pressure pan in the vicinity of the 
hydraulic fittings, and the hydraulic tube adapters.
    (i) If the repair required by paragraph (h)(1) of this AD is 
done after the effective date of this AD: Revise the Airworthiness 
Limitations section within 12 months after the repair.
    (ii) If the repair required by paragraph (h)(1) of this AD was 
accomplished before July 27, 2005: Revise the Airworthiness

[[Page 64194]]

Limitations section within 12 months after the repair or 30 days 
after July 27, 2005, whichever occurs later.

Alternative Methods of Compliance (AMOCs)

    (i)(1) The Manager, New York ACO, FAA, ATTN: Pong Lee, Aerospace 
Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York 
ACO, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; 
telephone (516) 228-7324; fax (516) 794-5531; has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.

Related Information

    (j) Canadian airworthiness directive CF-2004-14, dated July 20, 
2004, also addresses the subject of this AD.

Material Incorporated by Reference

    (k) You must use Bombardier CRJ 700/900 Series Temporary 
Revision MRM2-129, dated June 1, 2004, to perform the actions that 
are required by this AD, unless the AD specifies otherwise.
    (1) On July 27, 2005 (70 FR 35987, June 22, 2005), the Director 
of the Federal Register approved the incorporation by reference of 
Bombardier CRJ 700/900 Series Temporary Revision MRM2-129, dated 
June 1, 2004.
    (2) 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 October 9, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-25637 Filed 10-28-08; 8:45 am]

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