Airworthiness Directives; Turbomeca Arriel 2S1 Turboshaft Engines, 55491-55493 [E9-25943]

Download as PDF Federal Register / Vol. 74, No. 207 / Wednesday, October 28, 2009 / Proposed Rules 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 EASA Airworthiness Directive 2009–0126, dated June 18, 2009; and Dassault Mandatory Service Bulletin F900EX–347, Revision 1, dated May 18, 2009; for related information. Issued in Renton, Washington, on October 19, 2009. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E9–25865 Filed 10–27–09; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2009–0568; Directorate Identifier 2009–NE–20–AD] RIN 2120–AA64 Airworthiness Directives; Turbomeca Arriel 2S1 Turboshaft Engines mstockstill on DSKH9S0YB1PROD with PROPOSALS 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) issued 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: During acceleration up to One Engine Inoperative (OEI) 30-second rating, one event of flight loss of full automatic control occurred on an Arriel 2S1 engine. The selection of OEI 30second rating on engine 1 was triggered by the automatic detection of an OEI situation further to a transient deceleration of engine 2. The transient deceleration of engine 2 was caused by the untimely reset of its DECU. Once this reset was completed, engine 2 resumed its nominal operation. VerDate Nov<24>2008 16:11 Oct 27, 2009 Jkt 220001 Afterwards the aircraft then continued its flight safely with its engine 1 operating in manual control mode. The loss of full automatic control of engine 1 was caused by loss of steps of the stepper motor controlling the fuel metering valve inside the Hydromechanical Unit (HMU). It has been found that high accelerations, notably up to OEI 30-second rating, increase the risk of loss of steps of the HMU stepper motor. Therefore, this event has led to the consideration of the following unsafe condition at aircraft level: In-flight loss of full automatic control of the engine induced by the loss of steps of the stepper motor during acceleration up to OEI 30-second rating, further to an actual OEI situation on the other engine (such as a power loss event). We are proposing this AD to prevent loss of full automatic control of the engine during acceleration up to the OEI 30-second rating. This condition could result in reduced controllability of the helicopter. DATES: We must receive comments on this proposed AD by November 27, 2009. ADDRESSES: You may send comments by any of the following methods: • Federal eRulemaking Portal: Go to https://www.regulations.gov and follow the instructions for sending your comments electronically. • Mail: Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., West Building Ground Floor, Room W12–140, Washington, DC 20590–0001. • Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. • Fax: (202) 493–2251. Examining the AD Docket You may examine the AD docket on the Internet at https:// 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 the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA PO 00000 Frm 00010 Fmt 4702 Sfmt 4702 55491 01803; e-mail: james.lawrence@faa.gov; telephone (781) 238–7176; fax (781) 238–7199. Contact Turbomeca, 40220 Tarnos, France; telephone (33) 05 59 74 40 00, fax (33) 05 59 74 45 15 for the service information identified in this AD. 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–2009–0568; Directorate Identifier 2009–NE–20–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 https:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of the Web site, anyone can find and read the comments in any of our dockets, including, if provided, the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT’s complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477–78). Discussion The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA Airworthiness Directive 2009–0010, dated January 20, 2009 (referred to after this as ‘‘the MCAI’’), to correct an unsafe condition for the specified products. The MCAI states: During acceleration up to One Engine Inoperative (OEI) 30-second rating, one event of flight loss of full automatic control occurred on an Arriel 2S1 engine. The selection of OEI 30-second rating on engine 1 was triggered by the automatic detection of an OEI situation further to a transient deceleration of engine 2. The transient deceleration of engine 2 was caused by the untimely reset of its DECU. Once this reset was completed, engine 2 resumed its nominal operation. Afterwards the aircraft then continued its flight safely with its engine 1 operating in manual control mode. The loss of full automatic control of engine 1 was caused by loss of steps of the stepper E:\FR\FM\28OCP1.SGM 28OCP1 55492 Federal Register / Vol. 74, No. 207 / Wednesday, October 28, 2009 / Proposed Rules motor controlling the fuel metering valve inside the Hydromechanical Unit (HMU). It has been found that high accelerations, notably up to OEI 30-second rating, increase the risk of loss of steps of the HMU stepper motor. Therefore, this event has led to the consideration of the following unsafe condition at aircraft level: In-flight loss of full automatic control of the engine induced by the loss of steps of the stepper motor during acceleration up to OEI 30-second rating, further to an actual OEI situation on the other engine (such as a power loss event). You may obtain further information by examining the MCAI in the AD docket. FAA’s Determination and Requirements of This Proposed AD This product has been approved by the aviation authority of France and is approved for operation in the United States. Pursuant to our bilateral agreement with France, they have notified us of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all information provided by EASA and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design. This proposed AD would require upgrading the DECU software to version 11.01, to implement modification of TU 109. Modification TU 109 increases the tolerance to loss of steps of the control system. It reduces significantly the risk of loss of full automatic control due to loss of steps of the stepper motor, notably during engine accelerations up to OEI 30-second rating. Differences Between This AD and the MCAI or Service Information The MCAI requires performing the DECU software upgrade no later than August 31, 2010. This proposed AD would require performing the DECU software upgrade within 350 operating hours after the effective date of the proposed AD. mstockstill on DSKH9S0YB1PROD with PROPOSALS Costs of Compliance Based on the service information, we estimate that this proposed AD would affect about 136 products of U.S. registry. We also estimate that it would take about 3 work-hours per product to comply with this proposed AD. The average labor rate is $80 per work-hour. Required parts would cost about $3,500 per product. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $508,640. Our cost estimate is exclusive of possible warranty coverage. VerDate Nov<24>2008 16:11 Oct 27, 2009 Jkt 220001 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 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, 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. PO 00000 Frm 00011 Fmt 4702 Sfmt 4702 § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new AD: Turbomeca: Docket No. FAA–2009–0568; Directorate Identifier 2009–NE–20–AD. Comments Due Date (a) We must receive comments by November 27, 2009. Affected Airworthiness Directives (ADs) (b) None. Applicability (c) This AD applies to Turbomeca Arriel 2S1 turboshaft engines that have not incorporated Modification TU 109. These engines are installed on, but not limited to, Sikorsky S–76C+ twin-engine helicopters. Reason (d) This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. We are issuing this AD to prevent loss of full automatic control of the engine during acceleration up to the One Engine Inoperative 30-second rating. This condition could result in reduced controllability of the helicopter. Actions and Compliance (e) Unless already done, do the following actions: (1) Within 350 operating hours after the effective date of this AD, perform an upgrade of the digital electronic control unit (DECU) software to version 11.01, to implement modification TU 109. (2) Guidance on implementing TU 109 can be found in Turbomeca Mandatory Service Bulletin No. 292 73 2109, Version E, dated September 17, 2008. Prohibition of Mixed DECU Software Versions on the Same Helicopter (3) Do not operate an Arriel 2S1-powered twin-engine helicopter with one engine upgraded to modification TU 109 if the other engine is not upgraded to modification TU 109. FAA AD Differences (f) This AD differs from the Mandatory Continuing Airworthiness Information (MCAI) and/or service information as follows: (1) The MCAI requires performing the DECU software upgrade no later than August 31, 2010. (2) This proposed AD would require performing the DECU software upgrade within 350 operating hours after the effective date of the proposed AD. Alternative Methods of Compliance (AMOCs) (g) The Manager, Engine Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Related Information (h) Refer to MCAI EASA Airworthiness Directive 2009–0010, dated January 20, 2009, E:\FR\FM\28OCP1.SGM 28OCP1 Federal Register / Vol. 74, No. 207 / Wednesday, October 28, 2009 / Proposed Rules and Turbomeca Mandatory Service Bulletin No. 292 73 2109, Version E, dated September 17, 2008, for related information. Contact Turbomeca, 40220 Tarnos, France; telephone (33) 05 59 74 40 00, fax (33) 05 59 74 45 15 for the service information identified in this AD. (i) Contact James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: james.lawrence@faa.gov; telephone (781) 238–7176; fax (781) 238– 7199, for more information about this AD. Issued in Burlington, Massachusetts, on October 1, 2009. Peter A. White, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. E9–25943 Filed 10–27–09; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2009–0995; Directorate Identifier 2009–NM–123–AD] RIN 2120–AA64 Airworthiness Directives; Bombardier 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), DOT. ACTION: Notice of proposed rulemaking (NPRM). mstockstill on DSKH9S0YB1PROD with PROPOSALS 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: 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. * * * VerDate Nov<24>2008 * * 16:11 Oct 27, 2009 Jkt 220001 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 14, 2009. ADDRESSES: You may send comments by any of the following methods: • Federal eRulemaking Portal: Go to https://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 W12–40, 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, ˆ Inc., 400 Cote-Vertu Road West, Dorval, ´ Quebec H4S 1Y9, Canada; telephone 514–855–5000; fax 514–855–7401; e-mail thd.crj@aero.bombardier.com; Internet https://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 or 425–227–1152. Examining the AD Docket You may examine the AD docket on the Internet at https:// 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 PO 00000 Frm 00012 Fmt 4702 Sfmt 4702 55493 to an address listed under the section. Include ‘‘Docket No. FAA–2009–0995; Directorate Identifier 2009–NM–123–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 have lengthened the 30-day comment period for proposed ADs that address MCAI originated by aviation authorities of other countries to provide adequate time for interested parties to submit comments. The comment period for these proposed ADs is now typically 45 days, which is consistent with the comment period for domestic transport ADs. We will post all comments we receive, without change, to https:// 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. ADDRESSES Discussion Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF–2009–22, dated May 14, 2009 (referred to after this as ‘‘the MCAI’’), 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. Relevant Service Information Bombardier has issued Alert Service Bulletin A670BA–32–022, Revision A, including Appendix A, dated May 1, 2009. The actions described in this service information are intended to E:\FR\FM\28OCP1.SGM 28OCP1

Agencies

[Federal Register Volume 74, Number 207 (Wednesday, October 28, 2009)]
[Proposed Rules]
[Pages 55491-55493]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-25943]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0568; Directorate Identifier 2009-NE-20-AD]
RIN 2120-AA64


Airworthiness Directives; Turbomeca Arriel 2S1 Turboshaft Engines

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) issued 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: During acceleration up to One Engine Inoperative (OEI) 
30-second rating, one event of flight loss of full automatic control 
occurred on an Arriel 2S1 engine. The selection of OEI 30-second rating 
on engine 1 was triggered by the automatic detection of an OEI 
situation further to a transient deceleration of engine 2. The 
transient deceleration of engine 2 was caused by the untimely reset of 
its DECU. Once this reset was completed, engine 2 resumed its nominal 
operation. Afterwards the aircraft then continued its flight safely 
with its engine 1 operating in manual control mode. The loss of full 
automatic control of engine 1 was caused by loss of steps of the 
stepper motor controlling the fuel metering valve inside the 
Hydromechanical Unit (HMU). It has been found that high accelerations, 
notably up to OEI 30-second rating, increase the risk of loss of steps 
of the HMU stepper motor. Therefore, this event has led to the 
consideration of the following unsafe condition at aircraft level: In-
flight loss of full automatic control of the engine induced by the loss 
of steps of the stepper motor during acceleration up to OEI 30-second 
rating, further to an actual OEI situation on the other engine (such as 
a power loss event).
    We are proposing this AD to prevent loss of full automatic control 
of the engine during acceleration up to the OEI 30-second rating. This 
condition could result in reduced controllability of the helicopter.

DATES: We must receive comments on this proposed AD by November 27, 
2009.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.

Examining the AD Docket

    You may examine the AD docket on the Internet at https://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 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: James Lawrence, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
james.lawrence@faa.gov; telephone (781) 238-7176; fax (781) 238-7199.
    Contact Turbomeca, 40220 Tarnos, France; telephone (33) 05 59 74 40 
00, fax (33) 05 59 74 45 15 for the service information identified in 
this AD.

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-2009-0568; 
Directorate Identifier 2009-NE-20-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 https://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, the name of the individual who 
sent the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78).

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Community, has issued EASA 
Airworthiness Directive 2009-0010, dated January 20, 2009 (referred to 
after this as ``the MCAI''), to correct an unsafe condition for the 
specified products. The MCAI states:

    During acceleration up to One Engine Inoperative (OEI) 30-second 
rating, one event of flight loss of full automatic control occurred 
on an Arriel 2S1 engine.
    The selection of OEI 30-second rating on engine 1 was triggered 
by the automatic detection of an OEI situation further to a 
transient deceleration of engine 2. The transient deceleration of 
engine 2 was caused by the untimely reset of its DECU. Once this 
reset was completed, engine 2 resumed its nominal operation. 
Afterwards the aircraft then continued its flight safely with its 
engine 1 operating in manual control mode.
    The loss of full automatic control of engine 1 was caused by 
loss of steps of the stepper

[[Page 55492]]

motor controlling the fuel metering valve inside the Hydromechanical 
Unit (HMU).
    It has been found that high accelerations, notably up to OEI 30-
second rating, increase the risk of loss of steps of the HMU stepper 
motor.
    Therefore, this event has led to the consideration of the 
following unsafe condition at aircraft level: In-flight loss of full 
automatic control of the engine induced by the loss of steps of the 
stepper motor during acceleration up to OEI 30-second rating, 
further to an actual OEI situation on the other engine (such as a 
power loss event).

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

FAA's Determination and Requirements of This Proposed AD

    This product has been approved by the aviation authority of France 
and is approved for operation in the United States. Pursuant to our 
bilateral agreement with France, they have notified us of the unsafe 
condition described in the MCAI and service information referenced 
above. We are proposing this AD because we evaluated all information 
provided by EASA and determined the unsafe condition exists and is 
likely to exist or develop on other products of the same type design. 
This proposed AD would require upgrading the DECU software to version 
11.01, to implement modification of TU 109. Modification TU 109 
increases the tolerance to loss of steps of the control system. It 
reduces significantly the risk of loss of full automatic control due to 
loss of steps of the stepper motor, notably during engine accelerations 
up to OEI 30-second rating.

Differences Between This AD and the MCAI or Service Information

    The MCAI requires performing the DECU software upgrade no later 
than August 31, 2010. This proposed AD would require performing the 
DECU software upgrade within 350 operating hours after the effective 
date of the proposed AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 136 products of U.S. registry. We also estimate that 
it would take about 3 work-hours per product to comply with this 
proposed AD. The average labor rate is $80 per work-hour. Required 
parts would cost about $3,500 per product. Based on these figures, we 
estimate the cost of the proposed AD on U.S. operators to be $508,640. 
Our cost estimate is exclusive of possible warranty coverage.

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 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, 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:

Turbomeca: Docket No. FAA-2009-0568; Directorate Identifier 2009-NE-
20-AD.

Comments Due Date

    (a) We must receive comments by November 27, 2009.

Affected Airworthiness Directives (ADs)

    (b) None.

Applicability

    (c) This AD applies to Turbomeca Arriel 2S1 turboshaft engines 
that have not incorporated Modification TU 109. These engines are 
installed on, but not limited to, Sikorsky S-76C+ twin-engine 
helicopters.

Reason

    (d) This AD results from mandatory continuing airworthiness 
information (MCAI) issued by an aviation authority of another 
country to identify and correct an unsafe condition on an aviation 
product. We are issuing this AD to prevent loss of full automatic 
control of the engine during acceleration up to the One Engine 
Inoperative 30-second rating. This condition could result in reduced 
controllability of the helicopter.

Actions and Compliance

    (e) Unless already done, do the following actions:
    (1) Within 350 operating hours after the effective date of this 
AD, perform an upgrade of the digital electronic control unit (DECU) 
software to version 11.01, to implement modification TU 109.
    (2) Guidance on implementing TU 109 can be found in Turbomeca 
Mandatory Service Bulletin No. 292 73 2109, Version E, dated 
September 17, 2008.

Prohibition of Mixed DECU Software Versions on the Same Helicopter

    (3) Do not operate an Arriel 2S1-powered twin-engine helicopter 
with one engine upgraded to modification TU 109 if the other engine 
is not upgraded to modification TU 109.

FAA AD Differences

    (f) This AD differs from the Mandatory Continuing Airworthiness 
Information (MCAI) and/or service information as follows:
    (1) The MCAI requires performing the DECU software upgrade no 
later than August 31, 2010.
    (2) This proposed AD would require performing the DECU software 
upgrade within 350 operating hours after the effective date of the 
proposed AD.

Alternative Methods of Compliance (AMOCs)

    (g) The Manager, Engine Certification Office, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19.

Related Information

    (h) Refer to MCAI EASA Airworthiness Directive 2009-0010, dated 
January 20, 2009,

[[Page 55493]]

and Turbomeca Mandatory Service Bulletin No. 292 73 2109, Version E, 
dated September 17, 2008, for related information. Contact 
Turbomeca, 40220 Tarnos, France; telephone (33) 05 59 74 40 00, fax 
(33) 05 59 74 45 15 for the service information identified in this 
AD.
    (i) Contact James Lawrence, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
james.lawrence@faa.gov; telephone (781) 238-7176; fax (781) 238-
7199, for more information about this AD.

    Issued in Burlington, Massachusetts, on October 1, 2009.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E9-25943 Filed 10-27-09; 8:45 am]
BILLING CODE 4910-13-P
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