
[Federal Register: June 23, 2010 (Volume 75, Number 120)]
[Rules and Regulations]               
[Page 35613-35616]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr23jn10-4]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0995; Directorate Identifier 2009-NM-123-AD; 
Amendment 39-16336; AD 2010-13-05]
RIN 2120-AA64

 
Airworthiness Directives; Bombardier, Inc. Model CL-600-2C10 
(Regional Jet Series 700 & 701) Airplanes, Model CL-600-2D15 (Regional 
Jet Series 705) Airplanes, and Model CL-600-2D24 (Regional Jet Series 
900) Airplanes

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

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) originated by an aviation authority of 
another country to identify and correct an unsafe condition on an 
aviation product. The MCAI describes the unsafe condition as:

    Investigation into a landing gear retraction problem on a 
production test flight revealed that, during aircraft pressurization 
and depressurization cycles, the pressure floor in the main landing 
gear bay deflects to a small extent. This causes relative 
misalignment between the [alternate-extension system] AES bypass 
valve, the downlock assist valve and the summing lever which, in 
turn, can result in damage to and potential failure of the 
respective clevis attached to one or both of the valves. Such a 
clevis failure could remain dormant and, in the subsequent event 
that use of the AES was required, full landing gear extension may 
not be achievable.
* * * * *
    We are issuing this AD to require actions to correct the unsafe 
condition on these products.

DATES: This AD becomes effective June 23, 2010.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of July 28, 
2010.

ADDRESSES: You may examine the AD docket on the Internet at http://
www.regulations.gov or in person at the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC.

FOR FURTHER INFORMATION CONTACT: Cesar Gomez, Aerospace Engineer, 
Airframe and Mechanical Systems Branch, ANE-171, FAA, New York Aircraft 
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New 
York 11590; telephone (516) 228-7318; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on October 28, 2009 (74 
FR 55493). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    Investigation into a landing gear retraction problem on a 
production test flight revealed that, during aircraft pressurization 
and depressurization cycles, the pressure floor in the main landing 
gear bay deflects to a small extent. This causes relative 
misalignment between the [alternate-extension system] AES bypass 
valve, the downlock assist valve and the summing lever which, in 
turn, can result in damage to and potential failure of the 
respective clevis attached to one or both of the valves. Such a 
clevis failure could remain dormant and, in the subsequent event 
that use of the AES was required, full landing gear extension may 
not be achievable.
    This directive gives instructions to replace the clevis, with a 
new part, for both the bypass and the downlock assist valves. It 
also gives instructions to install new support brackets for both 
valves, in order to increase the stiffness of the installations and 
thus prevent future relative misalignment and potential clevis 
failure.

    You may obtain further information by examining the MCAI in the AD 
docket.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received.

Support for the NPRM

    The Air Line Pilots Association, International (ALPA), supports the 
NPRM.

Request To Allow Repetitive Clevis Replacements in Lieu of Support 
Bracket Replacement

    Comair, Inc., requests that we revise the NPRM to allow repetitive 
replacement of the bypass valve clevis and downlock assist valve clevis 
at 6,000-flight-cycle intervals, until the new support brackets have 
been installed instead of requiring installation of the support 
brackets at the compliance times specified in paragraph (f)(3) of this 
AD. Comair, Inc., explains that Bombardier Alert Service Bulletin 
A670BA-32-022, dated November 8, 2007, established an initial 
replacement of the clevises along with a repetitive replacement every 
6,000 flight cycles. But with the introduction of Part C of Bombardier 
Alert Service Bulletin A670BA-32-022, Revision A, dated May 1, 2009, 
Comair, Inc., asserts that the repetitive interval was removed.
    Comair, Inc., states that it initiated the compliance with Parts A 
and B of Bombardier Alert Service Bulletin A670BA-32-022, dated 
November 8, 2007, in early 2008. Since the initial compliance time, 
Comair, Inc., states that nearly 2,900 flight cycles have passed and 
reasons that by the time the NPRM becomes a final rule, 500 or more 
flight cycles might pass. Comair, Inc., also explains that because of 
the proposed compliance times specified in paragraphs (f)(3)(ii) and 
(f)(3)(iii) of the NPRM, the installation of the new support brackets 
will be required within approximately 2,600 flight cycles (6,000 flight 
cycles minus 3,400 cycles).
    Comair, Inc., asserts that limiting installation of the new support 
brackets to 2,600 flight cycles instead of 4,500 flight cycles, as 
proposed by paragraph (f)(3)(i) of the NPRM, penalizes those operators 
who have taken early action to comply with Bombardier Alert Service 
Bulletin A670BA-32-022. To compensate for the loss of flight cycles, 
Comair, Inc., suggests that we revise paragraphs (f)(1) and (f)(2) of 
the NPRM to state: ``* * * Replacement of the clevises each 6,000 
flight cycles from the initial replacement, in order to

[[Page 35614]]

extend the compliance schedule in paragraph (f)(3) is acceptable.''
    We do not agree to allow repetitive replacements of the bypass 
valve clevis and downlock assist valve clevis until the new support 
bracket is installed. Comair, Inc., noted that the compliance time in 
paragraph (f)(3)(i) of the NPRM is 4,500 flight cycles; however, the 
compliance time is 4,500 flight hours. Operators that do the clevis 
replacement and operators that are not required to replace the clevis 
both have to comply with the 4,500 flight-hour compliance time to 
install the support brackets if that compliance time occurs first.
    However, we recognize the concern of Comair, Inc., in that the 
compliance time specified in paragraphs (f)(3)(ii) and (f)(3)(iii) of 
the NPRM (within 6,000 flight cycles after doing the clevis replacement 
or within 600 flight cycles after the effective date of this AD) 
penalizes those operators who have taken early action to comply with 
replacing the clevis in accordance with Bombardier Alert Service 
Bulletin A670BA-32-022, dated November 8, 2007. Therefore, we have 
increased the grace period specified in paragraphs (f)(3)(ii) and 
(f)(3)(iii) of this AD to allow operators that did the clevis 
replacement before the effective date of this AD additional time to do 
the installation of the bracket. We have determined that extending the 
grace period will not adversely affect safety and meets the intent of 
the MCAI, Canadian Airworthiness Directive CF-2009-22, dated May 14, 
2009. We have coordinated this change with Transport Canada Civil 
Aviation (TCCA).
    Under the provisions of paragraph (g) of the final rule, we will 
consider requests for approval of an extension of the compliance time 
for the installation of the new support brackets if sufficient data are 
submitted to substantiate that the new compliance time would provide an 
acceptable level of safety. We have not changed the AD in this regard.

Explanation of Change to This AD

    We have revised this AD to identify the legal name of the 
manufacturer as published in the most recent type certificate data 
sheet for the affected airplane models.

Conclusion

    We reviewed the available data, including the comments received, 
and determined that air safety and the public interest require adopting 
the AD with the change described previously. We determined that this 
change will not increase the economic burden on any operator or 
increase the scope of the AD.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have required different actions in this AD from those 
in the MCAI in order to follow our FAA policies. Any such differences 
are highlighted in a NOTE within the AD.

Explanation of Change to Costs of Compliance

    Since issuance of the NPRM, we have increased the labor rate used 
in the Costs of Compliance from $80 per work-hour to $85 per work-hour. 
The Costs of Compliance information, below, reflects this increase in 
the specified hourly labor rate.

Costs of Compliance

    We estimate that this AD will affect 203 products of U.S. registry. 
We also estimate that it will take about 12 work-hours per product to 
comply with the basic requirements of this AD. The average labor rate 
is $85 per work-hour. Required parts will cost about $939 per product. 
Where the service information lists required parts costs that are 
covered under warranty, we have assumed that there will be no charge 
for these parts. As we do not control warranty coverage for affected 
parties, some parties may incur costs higher than estimated here. Based 
on these figures, we estimate the cost of this AD to U.S. operators to 
be $397,677, or $1,959 per product.

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 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 this AD:
    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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains the NPRM, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Operations office (telephone (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

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 FAA amends Sec.  39.13 by adding the following new AD:

2010-13-05 Bombardier, Inc.: Amendment 39-16336. Docket No. FAA-
2009-0995; Directorate Identifier 2009-NM-123-AD.

[[Page 35615]]

Effective Date

    (a) This airworthiness directive (AD) becomes effective July 28, 
2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the airplanes identified in paragraphs 
(c)(1) and (c)(2) of this AD, certificated in any category.
    (1) Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700 
& 701) airplanes, serial numbers 10003 through 10216 inclusive.
    (2) Bombardier, Inc. Model CL-600-2D15 (Regional Jet Series 705) 
and Model CL-600-2D24 (Regional Jet Series 900) airplanes, serial 
numbers 15001 through 15039 inclusive.

Subject

    (d) Air Transport Association (ATA) of America Code 32: Landing 
Gear.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:

    Investigation into a landing gear retraction problem on a 
production test flight revealed that, during aircraft pressurization 
and depressurization cycles, the pressure floor in the main landing 
gear bay deflects to a small extent. This causes relative 
misalignment between the [alternate-extension system] AES bypass 
valve, the downlock assist valve and the summing lever which, in 
turn, can result in damage to and potential failure of the 
respective clevis attached to one or both of the valves. Such a 
clevis failure could remain dormant and, in the subsequent event 
that use of the AES was required, full landing gear extension may 
not be achievable.
    This directive gives instructions to replace the clevis, with a 
new part, for both the bypass and the downlock assist valves. It 
also gives instructions to install new support brackets for both 
valves, in order to increase the stiffness of the installations and 
thus prevent future relative misalignment and potential clevis 
failure.

Actions and Compliance

    (f) Unless already done, do the following actions.
    (1) For any bypass valve having part number (P/N) 53342-3, at 
the applicable time in paragraph (f)(1)(i), (f)(1)(ii), or 
(f)(1)(iii) of this AD, replace the existing clevis with a new 
clevis having P/N 2323H037, in accordance with Part A of the 
Accomplishment Instructions of Bombardier Alert Service Bulletin 
A670BA-32-022, Revision A, dated May 1, 2009. The replacement is not 
required if paragraph (f)(3) of this AD has already been done.
    (i) If the bypass valve has accumulated 9,400 total flight 
cycles or fewer as of the effective date of this AD, replace the 
clevis before the accumulation of 10,000 total flight cycles on the 
valve.
    (ii) If the bypass valve has accumulated more than 9,400 total 
flight cycles as of the effective date of this AD, replace the 
clevis within 550 flight hours after the effective date of this AD.
    (iii) If it is not possible to determine the total flight cycles 
accumulated on the bypass valve, replace the clevis within 550 
flight hours after the effective date of this AD.
    (2) For any downlock assist valve having P/N 53341-5, at the 
applicable time in paragraph (f)(2)(i), (f)(2)(ii), or (f)(2)(iii) 
of this AD, replace the existing clevis with a new clevis, having P/
N 2323H037, in accordance with Part B of the Accomplishment 
Instructions of Bombardier Alert Service Bulletin A670BA-32-022, 
Revision A, dated May 1, 2009. The replacement is not required if 
paragraph (f)(3) of this AD has already been done.
    (i) If the valve has accumulated 9,400 total flight cycles or 
fewer as of the effective date of this AD, replace the clevis before 
the valve has accumulated 10,000 total flight cycles on the valve.
    (ii) If the valve has accumulated more than 9,400 total flight 
cycles as of the effective date of this AD, replace the clevis 
within 550 flight hours after the effective date of this AD.
    (iii) If it is not possible to determine the total flight cycles 
accumulated by the downlock assist valve, replace the clevis within 
550 flight hours after the effective date of this AD.
    (3) At the earliest of the times in paragraphs (f)(3)(i), 
(f)(3)(ii), and (f)(3)(iii) of this AD, install new support brackets 
for the bypass valve and downlock assist valve, in accordance with 
Part C of the Accomplishment Instructions of Bombardier Alert 
Service Bulletin A670BA-32-022, Revision A, dated May 1, 2009. 
Installing the support brackets terminates the requirements of 
paragraphs (f)(1) and (f)(2) of this AD.
    (i) Within 4,500 flight hours after the effective date of this 
AD.
    (ii) Within 6,000 flight cycles after accomplishing the actions 
specified in paragraph (f)(1) of this AD, or 6,000 flight cycles 
after the effective date of this AD, whichever occurs later.
    (iii) Within 6,000 flight cycles after accomplishing the actions 
specified in paragraph (f)(2) of this AD, or 6,000 flight cycles 
after the effective date of this AD, whichever occurs later.
    (4) Replacing the clevises for the bypass valve and downlock 
assist valve before the effective date of this AD, in accordance 
with the Accomplishment Instructions of Bombardier Alert Service 
Bulletin A670BA-32-022, dated November 8, 2007, is considered 
acceptable for compliance with the corresponding actions specified 
in paragraphs (f)(1) and (f)(2) of this AD.

FAA AD Differences

    Note 1: This AD differs from the MCAI and/or service information 
as follows: No differences.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York Aircraft Certification Office (ACO), ANE-170, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19. Send information to Attn: Program 
Manager, Continuing Operational Safety, FAA, New York ACO, 1600 
Stewart Avenue, Suite 410, Westbury, New York 11590; telephone 516-
228-7300; fax 516-794-5531. Before using any approved AMOC on any 
airplane to which the AMOC applies, notify your principal 
maintenance inspector (PMI) or principal avionics inspector (PAI), 
as appropriate, or lacking a principal inspector, your local Flight 
Standards District Office. The AMOC approval letter must 
specifically reference this AD.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

Related Information

    (h) Refer to MCAI Canadian Airworthiness Directive CF-2009-22, 
dated May 14, 2009; and Bombardier Alert Service Bulletin A670BA-32-
022, Revision A, dated May 1, 2009; for related information.

Material Incorporated by Reference

    (i) You must use Bombardier Alert Service Bulletin A670BA-32-
022, Revision A, including Appendix A, dated May 1, 2009, to do the 
actions required by this AD, unless the AD specifies otherwise. (The 
revision level is not specified on pages A1 and A2, Appendix A, of 
this document; those pages are Revision A, dated May 1, 2009.)
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (2) For service information identified in this AD, contact 
Bombardier, Inc., 400 C[ocirc]te-Vertu Road West, Dorval, 
Qu[eacute]bec H4S 1Y9, Canada; telephone 514-855-5000; fax 514-855-
7401; e-mail thd.crj@aero.bombardier.com; Internet http://
www.bombardier.com.
    (3) You may review copies of the service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington. For information on the availability of this material at 
the FAA, call 425-227-1221.
    (4) You may also review copies of the service information that 
is incorporated by reference 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/code_of_federal_regulations/ 
ibr_locations.html.


[[Page 35616]]


    Issued in Renton, Washington, on June 10, 2010.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-14979 Filed 6-22-10; 8:45 am]
BILLING CODE 4910-13-P

