```

[Federal Register Volume 76, Number 216 (Tuesday, November 8, 2011)]
[Proposed Rules]
[Pages 69166-69168]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-28834]

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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-1228; Directorate Identifier 2011-NM-176-AD]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700, 
701, & 702), CL-600-2D15 (Regional Jet Series 705), CL-600-2D24 
(Regional Jet Series 900), and CL-600-2E25 (Regional Jet Series 1000) 
airplanes. This proposed 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:

    [I]t was found that the * * * ADG [air driven generator] GCU 
[generator control unit] transformer primary winding can break due 
to thermal fatigue. Broken transformer primary winding can prevent 
the supply of power from the ADG to the essential buses. In the 
event of an emergency, failure for the essential buses to remain 
powered can prevent continued safe flight.
* * * * *

The proposed AD would require actions that are intended to address the 
unsafe condition described in the MCAI.

[[Page 69167]]

DATES: We must receive comments on this proposed AD by December 23, 
2011.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
    For service information identified in this proposed 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; email 
thd.crj@aero.bombardier.com; Internet http://www.bombardier.com. You 
may review copies of the referenced 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.

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 this proposed AD, 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.

FOR FURTHER INFORMATION CONTACT: Assata Dessaline, Aerospace Engineer, 
Avionics and Flight Test Branch, ANE-172, FAA, New York Aircraft 
Certification Office (ACO), 1600 Stewart Avenue, Suite 410, Westbury, 
New York 11590; telephone (516) 228-7301; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2011-1228; 
Directorate Identifier 2011-NM-176-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD based on those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued Canadian Airworthiness Directive CF-
2011-27, dated July 25, 2011 (referred to after this as ``the MCAI''), 
to correct an unsafe condition for the specified products. The MCAI 
states:

    There have been several occurrences of the air driven generator 
(ADG) failure to power essential buses during functional tests of 
the ADG on aeroplane models CL-600-2B16 and CL-600-2B19. The 
aeroplane models CL-600-2C10, CL-600-2D15, CL-600-2D24, and CL-600-
2E25 use the same ADG generator control unit (GCU) as models CL-600-
2B16 and CL-600-2B19. However the aeroplane models CL-600-2C10, CL-
600-2D15, CL-600-2D24, and CL-600-2E25 are installed with a 
different hydraulic pump and do not experience the same failure due 
to the low threshold setting of the circuit protection. However, it 
was found that the same ADG GCU transformer primary winding can 
break due to thermal fatigue. Broken transformer primary winding can 
prevent the supply of power from the ADG to the essential buses. In 
the event of an emergency, failure for the essential buses to remain 
powered can prevent continued safe flight.
    This [TCCA] directive mandates the replacement of the ADG GCU.

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

Relevant Service Information

    Bombardier, Inc. has issued Service Bulletin 670BA-24-031, dated 
May 30, 2011. The actions described in this service information are 
intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed AD

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with the State of Design Authority, we have 
been notified of the unsafe condition described in the MCAI and service 
information referenced above. We are proposing this AD because we 
evaluated all pertinent information and determined an unsafe condition 
exists and is likely to exist or develop on other products of the same 
type design.

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 proposed different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a NOTE within the proposed AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 402 products of U.S. registry. We also estimate that 
it would take about 2 work-hours per product to comply with the basic 
requirements of this proposed AD. The average labor rate is $85 per 
work-hour. Required parts would cost about $0 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 the proposed AD on U.S. operators to 
be $68,340, or $170 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

[[Page 69168]]

that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); and
    3. 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 proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

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

Bombardier, Inc.: Docket No. FAA-2011-1228; Directorate Identifier 
2011-NM-176-AD.

Comments Due Date

    (a) We must receive comments by December 23, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the airplanes, certificated in any 
category, identified in paragraphs (c)(1), (c)(2), and (c)(3) of 
this AD.
    (1) Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700, 
701, & 702) airplanes, serial numbers 10003 through 10319 inclusive.
    (2) Bombardier, Inc. Model CL-600-2D15 (Regional Jet Series 705) 
and CL-600-2D24 (Regional Jet Series 900) airplanes, serial numbers 
15001 through 15260 inclusive.
    (3) Bombardier, Inc. Model CL-600-2E25 (Regional Jet Series 
1000) airplanes, serial numbers 19001 through 19012 inclusive.

Subject

    (d) Air Transport Association (ATA) of America Code 24: 
Electrical Power.

Reason

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

    [I]t was found that the * * * ADG [air driven generator] GCU 
[generator control unit] transformer primary winding can break due 
to thermal fatigue. Broken transformer primary winding can prevent 
the supply of power from the ADG to the essential buses. In the 
event of an emergency, failure for the essential buses to remain 
powered can prevent continued safe flight.
* * * * *

Compliance

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

Actions

    (g) Within 10,000 flight hours or 60 months after the effective 
date of this AD, whichever occurs first, remove the ADG GCU, part 
number (P/N) 604-90800-7, and install a new or serviceable ADG GCU, 
P/N 604-90800-27, in accordance with the Accomplishment Instructions 
of Bombardier Service Bulletin 670BA-24-031, dated May 30, 2011.

Parts Installation

    (h) As of the effective date of this AD, no person may install 
an ADG GCU, P/N 604-90800-7, on any airplane.

FAA AD Differences

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

Other FAA AD Provisions

    (i) 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. In accordance with 14 CFR 39.19, 
send your request to your principal inspector or local Flight 
Standards District Office, as appropriate. If sending information 
directly to the ACO, send it 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, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
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.

Related Information

    (j) Refer to MCAI Canadian Airworthiness Directive CF-2011-27, 
dated July 25, 2011; and Bombardier Service Bulletin 670BA-24-031, 
dated May 30, 2011; for related information.

    Issued in Renton, Washington, on October 31, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-28834 Filed 11-7-11; 8:45 am]
BILLING CODE 4910-13-P
```