Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series Airplanes, 64849-64851 [2011-27023]

Download as PDF Federal Register / Vol. 76, No. 202 / Wednesday, October 19, 2011 / Proposed Rules 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 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: 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. [Amended] 2. The FAA amends § 39.13 by adding the following new AD: srobinson on DSK4SPTVN1PROD with PROPOSALS Bombardier, Inc.: Docket No. FAA–2011– 1090; Directorate Identifier 2011–NM– 138–AD. Comments Due Date (a) We must receive comments by December 5, 2011. Affected ADs (b) None. Applicability (c) This AD applies to Bombardier, Inc. Model DHC–8–400, –401, and –402 airplanes, certificated in any category, serial numbers 4001 through 4361 inclusive. VerDate Mar<15>2010 16:22 Oct 18, 2011 Jkt 226001 (d) Air Transport Association (ATA) of America Code 52: Doors. Reason (e) The mandatory continuing airworthiness information (MCAI) states: One case of the inability to open the airstair door while on ground was reported in service. The airstair door seal did not deflate, preventing the airstair door from opening. It was found that the existing airstair door pneumatic shut-off valve control logic prevents the airstair door seal from deflating due to a single Input/Output Module failure under certain conditions. The inability to open the airstair door could impede evacuation in the event of an emergency. * * * * * 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 6,000 flight hours after the effective date of this AD: Incorporate ModSum 4–126513, Seal System Shut Off Valve Control Logic Change, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84–52–69, Revision C, dated June 28, 2011. Credit for Actions Accomplished in Accordance With Previous Service Information (h) Actions accomplished before the effective date of this AD according to Bombardier Service Bulletin 84–52–69, dated January 28, 2011; Revision A, dated April 26, 2011; or Revision B, dated May 9, 2011; are considered acceptable for compliance with the corresponding actions specified in paragraph (g) of this AD. FAA AD Differences Note 1: This AD differs from the MCAI and/or service information as follows: No differences. PART 39—AIRWORTHINESS DIRECTIVES § 39.13 Subject 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 PO 00000 Frm 00011 Fmt 4702 Sfmt 4702 64849 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–2011–15, dated June 20, 2011; and Bombardier Service Bulletin 84–52–69, Revision C, dated June 28, 2011; for related information. Issued in Renton, Washington, on October 6, 2011. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2011–27009 Filed 10–18–11; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2011–1088; Directorate Identifier 2011–NM–099–AD] RIN 2120–AA64 Airworthiness Directives; Bombardier, Inc. Model DHC–8–400 Series Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: We propose to adopt a new airworthiness directive (AD) for the products listed above. 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: SUMMARY: Several operators have reported difficulties in opening the airstair door. Investigation revealed that the airstair door gearbox drain paths were blocked by sealant, causing water to accumulate and freeze in the gearbox assembly. An airstair door that is unable to be opened could hinder evacuation in the event of an emergency. * * * * * The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI. DATES: We must receive comments on this proposed AD by December 5, 2011. ADDRESSES: You may send comments by any of the following methods: E:\FR\FM\19OCP1.SGM 19OCP1 64850 Federal Register / Vol. 76, No. 202 / Wednesday, October 19, 2011 / Proposed Rules • 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., Q–Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416–375– 4000; fax 416–375–4539; e-mail thd.qseries@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: 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: srobinson on DSK4SPTVN1PROD with PROPOSALS 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–2011–1088; Directorate Identifier 2011–NM–099–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy VerDate Mar<15>2010 16:22 Oct 18, 2011 Jkt 226001 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. 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. Discussion The Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF–2011–06, dated April 26, 2011 (referred to after this as ‘‘the MCAI’’), to correct an unsafe condition for the specified products. The MCAI states: Costs of Compliance Based on the service information, we estimate that this proposed AD would affect about 83 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. 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 $14,110, or $170 per product. In addition, we estimate that any necessary follow-on actions would take about 3 work-hours and require parts costing $0, for a cost of $255 per product. We have no way of determining the number of products that may need these actions. Several operators have reported difficulties in opening the airstair door. Investigation revealed that the airstair door gearbox drain paths were blocked by sealant, causing water to accumulate and freeze in the gearbox assembly. An airstair door that is unable to be opened could hinder evacuation in the event of an emergency. This [Canadian] directive mandates a onetime [general visual] inspection [for sealant blockages] and [remove any] sealant interfering with the airstair gearbox drain paths. You may obtain further information by examining the MCAI in the AD docket. Relevant Service Information Bombardier, Inc. has issued Service Bulletin 84–53–48, dated December 2, 2010. 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. PO 00000 Frm 00012 Fmt 4702 Sfmt 4702 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 proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a E:\FR\FM\19OCP1.SGM 19OCP1 Federal Register / Vol. 76, No. 202 / Wednesday, October 19, 2011 / Proposed Rules 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. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new AD: Bombardier, Inc.: Docket No. FAA–2011– 1088; Directorate Identifier 2011–NM– 099–AD. Comments Due Date (a) We must receive comments by December 5, 2011. Affected ADs (b) None. srobinson on DSK4SPTVN1PROD with PROPOSALS Applicability (c) This AD applies to Bombardier, Inc. Model DHC–8–400, –401, and –402 airplanes; certificated in any category; serial numbers 4161 through 4296 inclusive. Subject (d) Air Transport Association (ATA) of America Code 53: Fuselage. Reason (e) The mandatory continuing airworthiness information (MCAI) states: Several operators have reported difficulties in opening the airstair door. Investigation revealed that the airstair door gearbox drain paths were blocked by sealant, causing water VerDate Mar<15>2010 16:22 Oct 18, 2011 Jkt 226001 to accumulate and freeze in the gearbox assembly. An airstair door that is unable to be opened could hinder evacuation in the event of an emergency. * * * * * BILLING CODE 4910–13–P (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. DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Actions (g) Within 600 flight hours after the effective date of this AD, do a general visual inspection of the structure and gearbox drain paths for blockages by sealant, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84–53–48, dated December 2, 2010. If any blockages are found, before further flight, remove blockages in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84–53–48, dated December 2, 2010. FAA AD Differences Note 1: This AD differs from the MCAI and/or service information as follows: No differences. Other FAA AD Provisions (h) 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 (i) Refer to MCAI Transport Canada Civil Aviation (TCCA) Airworthiness Directive CF–2011–06, dated April 26, 2011; and Bombardier Service Bulletin 84–53–48, dated December 2, 2010; for related information. Frm 00013 Issued in Renton, Washington, on October 6, 2011. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2011–27023 Filed 10–18–11; 8:45 am] Compliance PO 00000 64851 Fmt 4702 Sfmt 4702 14 CFR Part 39 [Docket No. FAA–2011–1069; Directorate Identifier 2011–NM–025–AD] RIN 2120–AA64 Airworthiness Directives; Learjet Inc. Model 45 Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD would require revising the maintenance program to include new or more restrictive life-limits and inspections. This proposed AD was prompted by changes to the Airworthiness Limitations Section (ALS) of the maintenance manual, which adds life-limits, revises lifelimits, or adds inspections not previously identified. We are proposing this AD to limit exposure of flight critical components to corrosion, cracking, or failure due to life-limits, which if not corrected, could result in loss of roll control, fatigue cracking, or loss of structural components. DATES: We must receive comments on this proposed AD by December 5, 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: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this proposed AD, contact Learjet, Inc., One Learjet Way, Wichita, Kansas 67209–2942; phone 316–946–2000; fax 316–946–2220; e-mail ac.ict@aero.bombardier.com; Internet SUMMARY: E:\FR\FM\19OCP1.SGM 19OCP1

Agencies

[Federal Register Volume 76, Number 202 (Wednesday, October 19, 2011)]
[Proposed Rules]
[Pages 64849-64851]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-27023]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-1088; Directorate Identifier 2011-NM-099-AD]
RIN 2120-AA64


Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. 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:

    Several operators have reported difficulties in opening the 
airstair door. Investigation revealed that the airstair door gearbox 
drain paths were blocked by sealant, causing water to accumulate and 
freeze in the gearbox assembly. An airstair door that is unable to 
be opened could hinder evacuation in the event of an emergency.
* * * * *
The proposed AD would require actions that are intended to address the 
unsafe condition described in the MCAI.

DATES: We must receive comments on this proposed AD by December 5, 
2011.

ADDRESSES: You may send comments by any of the following methods:

[[Page 64850]]

     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., Q-Series Technical Help Desk, 123 Garratt Boulevard, 
Toronto, Ontario M3K 1Y5, Canada; telephone 416-375-4000; fax 416-375-
4539; e-mail thd.qseries@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: 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:

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-2011-1088; 
Directorate Identifier 2011-NM-099-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

    The Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued Canadian Airworthiness Directive CF-
2011-06, dated April 26, 2011 (referred to after this as ``the MCAI''), 
to correct an unsafe condition for the specified products. The MCAI 
states:

    Several operators have reported difficulties in opening the 
airstair door. Investigation revealed that the airstair door gearbox 
drain paths were blocked by sealant, causing water to accumulate and 
freeze in the gearbox assembly. An airstair door that is unable to 
be opened could hinder evacuation in the event of an emergency.
    This [Canadian] directive mandates a one-time [general visual] 
inspection [for sealant blockages] and [remove any] sealant 
interfering with the airstair gearbox drain paths.

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

Relevant Service Information

    Bombardier, Inc. has issued Service Bulletin 84-53-48, dated 
December 2, 2010. 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 83 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. 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 $14,110, or $170 per product.
    In addition, we estimate that any necessary follow-on actions would 
take about 3 work-hours and require parts costing $0, for a cost of 
$255 per product. We have no way of determining the number of products 
that may need these actions.

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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a

[[Page 64851]]

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-2011-1088; Directorate Identifier 
2011-NM-099-AD.

Comments Due Date

    (a) We must receive comments by December 5, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Bombardier, Inc. Model DHC-8-400, -401, 
and -402 airplanes; certificated in any category; serial numbers 
4161 through 4296 inclusive.

Subject

    (d) Air Transport Association (ATA) of America Code 53: 
Fuselage.

Reason

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

    Several operators have reported difficulties in opening the 
airstair door. Investigation revealed that the airstair door gearbox 
drain paths were blocked by sealant, causing water to accumulate and 
freeze in the gearbox assembly. An airstair door that is unable to 
be opened could hinder evacuation in the event of an emergency.
* * * * *

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 600 flight hours after the effective date of this AD, 
do a general visual inspection of the structure and gearbox drain 
paths for blockages by sealant, in accordance with the 
Accomplishment Instructions of Bombardier Service Bulletin 84-53-48, 
dated December 2, 2010. If any blockages are found, before further 
flight, remove blockages in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletin 84-53-48, dated December 
2, 2010.

FAA AD Differences

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

Other FAA AD Provisions

    (h) 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

    (i) Refer to MCAI Transport Canada Civil Aviation (TCCA) 
Airworthiness Directive CF-2011-06, dated April 26, 2011; and 
Bombardier Service Bulletin 84-53-48, dated December 2, 2010; for 
related information.

    Issued in Renton, Washington, on October 6, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-27023 Filed 10-18-11; 8:45 am]
BILLING CODE 4910-13-P