### 4648 Federal Register / Vol. 77, No. 20 / Tuesday, January 31, 2012 / Rules and Regulations

safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify this 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);

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.

We prepared a regulatory evaluation of the estimated costs to comply with this 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. 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 adding the following new AD:
2012–02–12 Bombardier, Inc.: Amendment 39–16935. Docket No. FAA–2012–0037; Directorate Identifier 2012–NM–003–AD.
(a) Effective Date

This airworthiness directive (AD) becomes effective February 15, 2012.
(b) Affected ADs

None. (c) Applicability

This AD applies to Bombardier, Inc. Model DHC–8–400, –401, and –402 airplanes; certificated in any category; serial numbers 4095 through 4391 inclusive.
(d) Subject

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

This AD was prompted by multiple reports of the loss of certain alternating current (AC) systems caused by a burnt AC power wire bundle. We are issuing this AD to prevent the loss of ice protection systems for the angle of attack vanes, pitot probes, engine inlets, and windshields, and consequent loss of or misleading airspeed indication and increased workload for the flight crew, which could lead to loss of control of the airplane.
(f) Compliance

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

Within 400 flight hours or 60 days, whichever occurs first, after the effective date of this AD, do the actions specified in paragraphs (g)(1) and (g)(2) of this AD.

(1) Do a detailed inspection of the affected AC power wire bundle for damage (any foreign object damage (FOD), damage due to sharp bends and kinking or deterioration, insulation cracking, evidence of heat damage to the insulation, and chafing) and do all applicable repairs, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84–24–52, dated November 22, 2011. Do all applicable repairs before further flight.

(2) Segregate the AC power wire bundle into two bundles and install Teflon tubing, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84–24–52, dated November 22, 2011.
(h) Other FAA AD Provisions

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.
(i) Related Information

Refer to MCAI Canadian Airworthiness Directive CF–2011–46, dated December 20, 2011; and Bombardier Service Bulletin 84– 24–52, dated November 22, 2011; for related information.
(j) Material Incorporated by Reference

(1) 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) of the following service information under 5 U.S.C. 552(a) and 1 CFR part 51:

(i) Bombardier Service Bulletin 84–24–52, dated November 22, 2011.

(2) For Bombardier, Inc. service information identified in this 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; email
t hd.qseries@aero.bombardier.com; Internet http://www.bombardier.com.

(3) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call (425) 227–1221.

(4) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at 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 January 23, 2012. Kalene C. Yanamura, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2012–1993 Filed 1–30–12; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2009–0994; Directorate Identifier 2009–NE–39–AD; Amendment 39–**  **16934; AD 2012–02–11]**

**RIN 2120–AA64**

**Airworthiness Directives; Rolls-Royce plc (RR) RB211–535 Series Turbofan**  **Engine**

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

**ACTION :**  Final rule.

**SUMMARY :**  We are superseding an existing airworthiness directive (AD) for


### 4649 Federal Register / Vol. 77, No. 20 / Tuesday, January 31, 2012 / Rules and Regulations

all RR RB211–535E4–37, –535E4–B–37, –535E4–B–75, and –535E4–C–37 turbofan engines. That AD currently requires performing initial and repetitive visual and fluorescentpenetrant inspections (FPI) of the lowpressure (LP) turbine stage 1, 2, and 3 discs to detect cracks in the discs. This new AD continues to require those inspections and changes the definition of a shop visit to be less restrictive. This AD was prompted by our finding that the definition of shop visit in the existing AD was too restrictive. We are issuing this AD to revise the definition of shop visit and to detect cracks in the LP turbine stage 1, 2, and 3 discs, which could result in an uncontained release of LP turbine blades and damage to the airplane.

**DATES :**  This AD is effective March 6,
2012.

**ADDRESSES :**  For service informationidentified in this AD, contact RollsRoyce plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; phone: 011 44 1332 242424, fax: 011 44 1332 249936; or email: http://www.rolls-royce.com/ contact/civil

_ team.jsp, or download the publication from https://
www.aeromanager.com. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803. 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 :**  Alan Strom, Aerospace Engineer, Engine Certification Office, FAA, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238–7143; fax: (781) 238–7199; email: alan.strom@faa.gov.

**SUPPLEMENTARY INFORMATION :** 
Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2011–11–08, amendment 39–16707 (76 FR 30529, May 26, 2011). That AD applies to the specified products. The NPRM was published in the Federal Register on October 25, 2011 (76 FR 65997). That NPRM proposed to continue to require performing an initial FPI on the LP turbine stage 1, 2, and 3 discs at the next engine shop inspection after the effective date of that AD. That NPRM also continued to require repetitive inspections at each engine shop visit after accumulating 1,500 cycles since last inspection of the LP turbine stage 1, 2, and 3 discs. That NPRM also proposed to change the definition of a shop visit to be less restrictive.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (76 FR 65997, October 25, 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. Costs of Compliance

We estimate that this AD affects about 588 RB211–535 series turbofan engines installed on airplanes of U.S. registry. We also estimate that it will take about 30 work-hours per product to comply with this AD. The average labor rate is $85 per work-hour. No parts are required. Based on these figures, we estimate the cost of this AD on U.S. operators to be $1,499,400. 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) 2011–11–08, Amendment 39–16707 (76 FR 30529, May 26, 2011, and adding the following new AD: 2012–02–11 Rolls-Royce plc: Amendment 39–16934; Docket No. FAA–2009–0994; Directorate Identifier 2009–NE–39–AD.
(a) Effective Date

This airworthiness directive (AD) is effective March 6, 2012.
(b) Affected ADs

This AD supersedes AD 2011–11–08, Amendment 39–16707 (76 FR 30529, May 26, 2011).
(c) Applicability

This AD applies to Rolls-Royce plc RB211– 535E4–37, –535E4–B–37, –535E4–B–75, and –535E4–C–37 turbofan engines.
(d) Unsafe Condition

This AD was prompted by our determination that the definition of ‘‘shop visit’’ in the existing AD is too restrictive, in


### 4650 Federal Register / Vol. 77, No. 20 / Tuesday, January 31, 2012 / Rules and Regulations

that it would require operators to inspect more often than required to ensure safety. We are issuing this AD to revise the definition ofshop visit and to detect cracks in the lowpressure (LP) turbine stage 1, 2, and 3 discs, which could result in an uncontained release of LP turbine blades and damage to the airplane.
(e) Compliance

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

At the next engine shop visit after the effective date of this AD, perform a visual and a fluorescent penetrant inspection of the LP turbine stage 1, 2, and 3 discs.
(2) Repeat Inspection Requirements

At each engine shop visit after accumulating 1,500 cycles since the last inspection of the LP turbine stage 1, 2 and 3 discs, repeat the inspections specified in paragraph (e)(1) of this AD.

(3) Remove Cracked Discs

If you find cracks, remove the disc from
service.

(f) Definitions

For the purpose of this AD, an ‘‘engine shop visit’’ is induction of an engine into the shop for any purpose where:

(1) All the blades are removed from the high-pressure (HP) compressor discs and the HP turbine disc, or

(2) All the blades are removed from the intermediate pressure turbine disc.
(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) Contact Alan Strom, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238–7143; fax: (781) 238–7199; email: alan.strom@faa.gov, for more information about this AD.

(2) Refer to MCAI European Aviation Safety Agency Airworthiness Directive 2009–0244, dated November 9, 2009, and RollsRoyce plc Alert Service Bulletin No. RB.211– 72–AG272 for related information. Contact Rolls-Royce plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; phone: 011 44 1332 242424, fax: 011 44 1332 249936; or email: http://www.rollsroyce.com/contact/ civil

_team.jsp, for a copy of this service information or download the publication from https://www.aeromanager.com.
(i) Material Incorporated by Reference

None. Issued in Burlington, Massachusetts, on January 25, 2012. Peter A. White, Manager, Engine & Propeller Directorate, Aircraft Certification Service.
[FR Doc. 2012–1954 Filed 1–30–12; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2010–0068; Directorate Identifier 2010–NE–05–AD; Amendment 39–**  **16930; AD 2012–02–07]**

**RIN 2120–AA64**

**Airworthiness Directives; General Electric Company Turbofan Engines** 

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

**ACTION :**  Final rule.

**SUMMARY :**  We are superseding two existing airworthiness directives (ADs) for General Electric Company (GE) CF6– 45 and CF6–50 series turbofan engines with certain low-pressure turbine (LPT) rotor stage 3 disks installed. The existing ADs currently require inspections of high-pressure turbine (HPT) and LPT rotors, engine checks, and vibration surveys. This new AD retains the requirements of the two ADs being superseded, adds an optional LPT rotor stage 3 disk removal after a failed HPT blade borescope inspection (BSI) or a failed engine core vibration survey, establishes a new lower life limit for the affected LPT rotor stage 3 disks, and requires removing these disks from service at times determined by a drawdown plan. This AD was prompted by the determination that a new lower life limit for the LPT rotor stage 3 disks is necessary. We are issuing this AD to prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane.

**DATES :**  This AD is effective March 6,
2012.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of February 22, 2011 (76 FR 6323, February 4, 2011).

**ADDRESSES :**  For service information identified in this AD, contact General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 45215, phone: (513) 552–3272; email: geae.aoc@ge.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 :**  Tomasz Rakowski, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238–7735; fax: (781) 238– 7199; email: tomasz.rakowski@faa.gov.

**SUPPLEMENTARY INFORMATION :** 
Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2011–02–07, Amendment 39–16580 (76 FR 6323, February 4, 2011) and AD 2011–18–01, Amendment 39–16783 (76 FR 52213, August 22, 2011). Those ADs apply to the specified products. The NPRM published in the Federal Register on October 19, 2011 (76 FR 64844). That NPRM proposed to retain the requirements of AD 2011–02–07 and AD 2011–18–01, except that reporting to the FAA would no longer be required and there would be an optional LPT rotor stage 3 disk removal after a failed HPT blade BSI or a failed engine core vibration survey. That NPRM also proposed to establish a new lower life limit for the LPT rotor stage 3 disk part numbers listed in Table 1 of the proposed AD, and proposed to require removing these disks from service at times determined by a drawdown plan.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal and the FAA’s response to each comment. Support for the NPRM as Written

One commenter, The Boeing Company, supports the NPRM (76 FR 64844, October 19, 2011) as written.