### 77378 Federal Register / Vol. 76, No. 239 / Tuesday, December 13, 2011 / Rules and Regulations

plates for a split caused by exfoliation corrosion, in accordance with the Accomplishment Instructions of BAE SYSTEMS (Operations) Limited Service Bulletin J41–52–064, dated September 15, 2009. Repeat the ultrasonic inspection, thereafter, at intervals not to exceed 48 months.

(h) If a split caused by exfoliation corrosion of an area of 78mm 2 (0.12 in. 2 ) or greater is found during any ultrasonic inspection required by paragraph (g) of this AD: Before further flight, replace any affected guide plates with a serviceable guide plate, in accordance with the Accomplishment Instructions of BAE Systems (Operations) Limited Service Bulletin J41–52–064, dated September 15, 2009.

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, International Branch, ANM–116, 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 International Branch, send it to ATTN: Todd Thompson, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, Washington 98057– 3356; telephone (425) 227–1175; fax (425) 227–1149. Information may be emailed to: 9- ANM-116-AMOC-REQUESTS@faa.gov. 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 European Aviation Safety Agency Airworthiness Directive 2010–0179, dated August 30, 2010; and BAE Systems (Operations) Limited Service Bulletin J41– 52–064, dated September 15, 2009; for related information.
Material Incorporated by Reference

(k) You must use the following service information to do the actions required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the following service information on the date specified:

(1) BAE Systems (Operations) Limited Service Bulletin J41–52–064, dated September 15, 2009, approved for IBR January 17, 2012.

(2) For BAE Systems (Operations) Limited service information identified in this AD, contact Customer Information Department, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland, United Kingdom; telephone +44 1292 675207; fax +44 1292 675704; email RApublications@baesystems.com; Internet http://www.baesystems.com/Businesses/ RegionalAircraft/index.htm.

(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 an NARA facility, call (202) 741– 6030, or go to http://www.archives.gov/ federal

_register/code

_ of

_ federal

_regulations/ ibr

_ locations.html. Issued in Renton, Washington, on November 23, 2011. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2011–31314 Filed 12–12–11; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2010–0710; Directorate Identifier 2010–NE–26–AD; Amendment**  **39–16892; AD 2011–26–02]**

**RIN 2120–AA64**

**Airworthiness Directives; Turbomeca Arriel 1 Series Turboshaft Engines** 

**AGENCY :**  Federal Aviation Administration (FAA), DOT.

**ACTION :**  Final rule.

**SUMMARY :**  We are revising an existing airworthiness directive (AD) for the products listed above. This AD was prompted by Turbomeca restoring all or part of the life limits of the affected discs, and European Aviation Safety Agency’s (EASA) issuance of AD 2010– 0101R2, dated March 24, 2011, to do the same. Turbomeca has introduced a reinforced eddy-current inspection (ECI) which, combined with a revised analysis, allows the life limit of the affected discs to be extended. We are issuing this revision to prevent failure of the gas generator (GG) second stage turbine disc which could result in the release of high energy debris and damage to the helicopter.

**DATES :**  This AD is effective January 17,
2012.

**ADDRESSES :**  For service information identified in this AD, contact Turbomeca, 40220 Tarnos, France; phone: 33 05 59 74 40 00; fax: 33 05 59 74 45 15; email: noriadallas@turbomeca.com. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call (781) 238–
7125. Examining the AD Docket

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

**FOR FURTHER INFORMATION CONTACT :**  Frederick Zink, Aerospace Engineer, Engine Certification Office, FAA, 12 New England Executive Park, Burlington, MA; phone: (781) 238–7779; fax: (781) 238–7199; email: frederick.zink@faa.gov.

**SUPPLEMENTARY INFORMATION :** 

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to revise AD 2010–19–06, amendment 39–16434 (75 FR 57371, September 21, 2010). That AD applies to the specified products. The NPRM published in the Federal Register on July 19, 2011 (76 FR 42610). That NPRM proposed to require removing GG second stage turbine discs, P/N 0 292 25 040 0, that do not have the ‘‘CFR’’ marking, from service before exceeding 4,000 cycles-in-service (CIS) since-new. That NPRM also proposed to require removing GG second stage turbine discs, P/N 0 292 25 040 0, that have the ‘‘CFR’’ marking, from service before exceeding 6,500 CIS since-new.

That NPRM was prompted by Turbomeca restoring all or part of the life limits of the affected discs, per


### 77379 Federal Register / Vol. 76, No. 239 / Tuesday, December 13, 2011 / Rules and Regulations

EASA’s issuance of AD 2010–0101R2, dated March 24, 2011, to do the same. Turbomeca’s reinforced ECI provides a lower (improved) detection threshold for metallurgical non-conformities. This reinforced ECI, combined with a revised analysis, allows the life limit of the post-TU347 GG second stage turbine discs identified as ‘‘CFR’’ to be extended to 6,500 CIS since-new. Further, as a result of this testing and analysis, thenon-CFR 2nd stage turbine discs preTU347 inspection disc life has been extended to 4,000 CIS since-new. This new AD still prevents disc failure but also extends the life limits of the affected discs. We are issuing this revision to prevent failure of the GG second stage turbine disc which could result in the release of high energy debris and damage to the helicopter.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (76 FR 42610, July 19, 2011) or on the determination of the cost to the public.

Conclusion

We reviewed the relevant data and determined that air safety and the public interest require adopting the AD as proposed except for minor clarifications. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM (76 FR 42610, July 19, 2011) for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM (76 FR 42610, July 19, 2011). Costs of Compliance

We estimate that this AD will affect 203 Turbomeca Arriel 1 series turboshaft engines on helicopters of U.S. registry. We estimate that no additional labor costs will be incurred to return part of the life limit of the discs that do not have the ‘‘CFR’’ marking to the original published life limit. Based on these figures, we estimate the total cost of this AD to U.S. operators to be $0. 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 have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866,

(2) Is not a ‘‘significant rule’’ under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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. List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 removing airworthiness directive (AD) 2010–19–06, Amendment 39–16434 (75 FR 57371, September 21, 2010), and adding the following new AD:

2011–26–02 Turbomeca: Amendment 39– 16892; Docket No. FAA–2010–0710; Directorate Identifier 2010–NE–26–AD.

(a) Effective Date

This airworthiness directive (AD) is effective January 17, 2012. (b) Affected ADs
This AD revises AD 2010–19–06, Amendment 39–16434.
(c) Applicability

This AD applies to Turbomeca Arriel 1A, 1A1, 1B, 1C, 1C1, 1C2, 1D, 1D1, and 1S1 turboshaft engines that have incorporated Modification TU347.

(d) Unsafe Condition

This AD was prompted by Turbomeca restoring all or part of the life limits of the affected discs. We are issuing this AD to prevent failure of the gas generator (GG) second stage turbine disc which could result in the release of high energy debris and damage to the helicopter.
(e) Compliance

(1) Comply with this AD within the compliance times specified, unless already done.

(2) Remove from service the GG second stage turbine discs, part number (P/N) 0 292 25 040 0, that do not have the ‘‘CFR’’ marking before exceeding 4,000 cycles-in-service (CIS) since-new.

(3) Remove from service gas generator second stage turbine discs, P/N 0 292 25 040 0, that have the ‘‘CFR’’ marking before exceeding 6,500 CIS since-new.
(f) Gas Generator Second Stage Turbine Installation Prohibition

(1) After the effective date of this AD, do not install into any engine gas generator second stage turbine discs, P/N 0 292 25 040 0, that do not have the ‘‘CFR’’ marking and have 4,000 or more CIS since-new.

(2) After the effective date of this AD, do not install into any engine gas generator second stage turbine discs, P/N 0 292 25 040 0, that have the ‘‘CFR’’ marking and have 6,500 or more CIS since-new.
(g) Alternative Methods of Compliance (AMOCs)

The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request.

(h) Related Information

(1) Refer to Turbomeca Alert Mandatory Service Bulletin No. A292 72 0831, Version C, for related information. Contact Turbomeca, 40220 Tarnos, France; phone: 33 05 59 74 40 00; fax: 33 05 59 74 45 15; or email: noria-dallas@turbomeca.com for a copy of this service information.

(2) You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call (781) 238–7125.

(3) For more information about this AD, contact Frederick Zink, Aerospace Engineer, Engine Certification Office, FAA, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238–7779; fax: (781) 238–7199; email: frederick.zink@faa.gov.
(i) Material Incorporated by Reference

None.


### 77380 Federal Register / Vol. 76, No. 239 / Tuesday, December 13, 2011 / Rules and Regulations

Issued in Burlington, MA, on December 5,
2011. Peter A. White, Manager, Engine & Propeller Directorate, Aircraft Certification Service.
[FR Doc. 2011–31797 Filed 12–12–11; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2011–1298; Directorate Identifier 2011–NE–39–AD; Amendment 39–**  **16888; AD 2011–25–12]**

**RIN 2120–AA64**

**Airworthiness Directives; Pratt & Whitney Canada Turboprop Engines** 

**AGENCY :**  Federal Aviation Administration (FAA), DOT.

**ACTION :**  Final rule; request for
comments.

**SUMMARY :**  We are adopting a new airworthiness directive (AD) for Pratt & Whitney Canada PT6A–15AG, –27, –28, –34, –34AG, –34B, and –36 series turboprop engines. This AD requires the removal of certain affected part manufacturer approval (PMA) replacement Timken Alcor Aerospace Technologies, Inc. (TAATI) first stage reduction sun gears and/or the interacting planetary gear sets from the propeller reduction gearbox assembly. This AD was prompted by a failure report of a certain TAATI PMA sun gear, installed since December 22, 2008. We are issuing this AD to prevent failure of the sun gear, which will result in an engine in-flight shut down, possible uncontained engine failure, aircraft damage, and serious injuries.

**DATES :**  This AD is effective December 28, 2011.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of December 28, 2011.

We must receive any comments on this AD by January 27, 2012.

**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 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Timken Alcor Aerospace Technologies, Inc., 3110 N. Oakland, Mesa, Arizona 85215; phone: (480) 632–1039; Web site: http:// www.timken.com/mro. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call (781) 238–
7125. Examining the AD Docket

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

**FOR FURTHER INFORMATION CONTACT :**  Paul Craig, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, 3960 Paramount Blvd., Suite 100, Lakewood, CA 90712; phone: (562) 627–5252; fax: (562) 627–5210; email: paul.craig@faa.gov.

**SUPPLEMENTARY INFORMATION :** 

Discussion

On October 12, 2011, we issued AD 2011–20–51, Amendment 39–16843 (76 FR 64001, October 17, 2011), for Pratt & Whitney Canada PT6A–15AG, –27, –28, –34, –34AG, –34B, and –36 series turboprop engines having a TAATI PMA replacement first stage reduction sun gear, part number (P/N) E3024765, installed.
Actions Since AD 2011–20–51 (76 FR 64001, October 17, 2011) Was Issued

Since we issued AD 2011–20–51, we received a report of another failure of a sun gear not listed in that AD. Analysis has revealed that additional PMA replacement TAATI gears, installed since December 22, 2008, have the same failure potential as the gears affected by that AD. The additional gears are identified as follows:

• Replacement first stage reduction sun gears, P/N E3024765, serial numbers (S/Ns) PC5–051 through PC5– 089, and S/Ns SG36–051 through SG36– 120, including the associated planetary gears in propeller reduction gearbox assembly.

• Replacement planetary gear sets, P/N E3101455–02, S/Ns EE–051 through EE–197, S/Ns EE–4051 through EE– 4094, and S/N EE–4113, including the associated sun gear in the propeller reduction gearbox assembly.

FAA’s Determination

We are issuing this AD because we evaluated all the relevant information and determined that the unsafe condition described previously is likely to exist or develop in other products of the same type design.
AD Requirements

This AD requires the removal of affected sun gears and planetary gear sets described previously.
FAA’s Justification and Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because of the short compliance time required in this AD to remove any affected parts from service. Therefore, we find that notice and opportunity for prior public comment are impracticable and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments before it becomes effective. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the **ADDRESSES** section. Include the docket number FAA–2011–1298 and directorate identifier 2011–NE–39–AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of 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 AD.