### 32439 Federal Register / Vol. 77, No. 106 / Friday, June 1, 2012 / Proposed Rules

(g) Alternative Methods of Compliance (AMOCs)

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

(1) For more information about this AD, contact Rose Len, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781–238–7772; fax: 781–238–7199; email: rose.len@faa.gov.

(2) European Aviation Safety Agency AD 2012–0054, dated April 2, 2012, also pertains to this AD.

(3) For service information identified in this AD, contact Turbomeca, 40220 Tarnos, France; phone: 33 (0)5 59 74 40 00; telex: 570 042; fax: 33 (0)5 59 74 45 15. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. 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.

Issued in Burlington, Massachusetts, on May 25, 2012. Pete A. White, Manager, Engine & Propeller Directorate, Aircraft Certification Service.
[FR Doc. 2012–13324 Filed 5–31–12; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2012–0496; Directorate Identifier 2011–NM–263–AD]** 

**RIN 2120–AA64**

**Airworthiness Directives; Bombardier Inc. Airplanes** 

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

**ACTION :**  Notice of proposed rulemaking (NPRM).

**SUMMARY :**  We propose to supersede an existing airworthiness directive (AD) that applies to certain Bombardier, Inc. Model CL–600–2B19 (Regional Jet Series 100 & 440) airplanes. The existing AD currently requires revising the airworthiness limitations section (AWL) of the instructions for continued airworthiness (ICA) of the Canadair Regional Jet Maintenance Requirements Manual by incorporating new procedures for repetitive detailed and special detailed inspections for cracking of the aft pressure bulkhead. Since we issued that AD, we have received multiple reports of cracks on the forward face of the rear pressure bulkhead (RPB) web. This proposed AD would require revising the maintenance program to incorporate a revised task specified in a certain temporary revision, which requires an improved non-destructive inspection procedure; and adds airplanes to the applicability. We are proposing this AD to detect and correct cracking in the RPB, which could result in reduced structural integrity and rapid decompression of the airplane.

**DATES :**  We must receive comments on this proposed AD by July 16, 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, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Bombardier, Inc., 400 Co ˆ te-Vertu Road West, Dorval, Que  ́ bec H4S 1Y9, Canada; telephone 514–855–5000; fax 514–855–7401; email thd.crj@aero.bombardier.com; Internet http://www.bombardier.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221. Examining the AD Docket

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

**FOR FURTHER INFORMATION CONTACT :**  Jeffrey Zimmer, Aerospace Engineer, Airframe & Mechanical Systems Branch, ANE–171, New York Aircraft Certification Office (ACO), FAA, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone (516) 228– 7306; 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–2012–0496; Directorate Identifier 2011–NM–263–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

On October 31, 2005, we issued AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005). That AD required actions intended to address an unsafe condition on the products listed above. Since we issued AD 2005–23–01, Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF–2011–30, dated August 11, 2011 (referred to after this as ‘‘the MCAI’’), to correct an unsafe condition for the specified products. The MCAI states:

Cracks on the forward face of the Rear Pressure Bulkhead (RPB) web have been discovered on three CL–600–2B19 aeroplanes in-service. This indicates that the existing inspection requirements of Airworthiness Limitation (AWL) task 53–61–153 mandated by [TCCA] AD CF–2005–13R1 are not adequate. Failure of the RPB could result in rapid decompression of the aeroplane.

A Temporary Revision has been made to Part 2 of the Maintenance Requirements Manual (MRM) to revise the existing AWLtask by introducing an improved NonDestructive Inspection (NDI) procedure to ensure that fatigue cracking of the RPB is detected and corrected.

This [TCCA] directive mandates the incorporation of a new NDI procedure for AWL task number 53–61–153.

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

Relevant Service Information

Bombardier Inc. has issued Temporary Revision 2B–2187, dated


### 32440 Federal Register / Vol. 77, No. 106 / Friday, June 1, 2012 / Proposed Rules

June 22, 2011, to Appendix B— Airworthiness Limitations, of Part 2 of the Bombardier CL–600–2B19 MRM. 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. Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 586 products of U.S. registry.

The actions that are required by AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005), and retained in this proposed AD take about 2 work-hours per product, at an average labor rate of $85 per work hour. Based on these figures, the estimated cost of the currently required actions is $170 per product.

We estimate that it would take about 1 work-hour per product to comply with the new basic requirements of this proposed AD. The average labor rate is $85 per work-hour. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $49,810, or $85 per product. Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. ‘‘Subtitle VII: Aviation Programs,’’ describes in more detail the scope of the Agency’s authority.

We are issuing this rulemaking under the authority described in ‘‘Subtitle VII, Part A, Subpart III, Section 44701: General requirements.’’ Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition 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);

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 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 removing airworthiness directive (AD) 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005), and adding the following new AD:
Bombardier, Inc.: Docket No. FAA–2012– 0496; Directorate Identifier 2011–NM– 263–AD.
(a) Comments Due Date

We must receive comments by July 16,
2012.
(b) Affected ADs

This AD supersedes AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005). (c) Applicability (1) This AD applies to Bombardier, Inc. Model CL–600–2B19 (Regional Jet Series 100 & 440) airplanes, certificated in any category, serial numbers 7003 and subsequent.

(2) This AD requires revisions to certain operator maintenance documents to include new inspections. Compliance with these inspections is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by these inspections, the operator may not be able to accomplish the inspections described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance according to paragraph (k)(1) of this AD. The request should include a description of changes to the required inspections that will ensure the continued damage tolerance of the affected structure. The FAA has provided guidance for this determination in FAA Advisory Circular (AC) 25.1529–1A, dated November 20, 2007 (http://rgl.faa.gov/ Regulatory

_ and

_ Guidance

_Library/ rgAdvisoryCircular.nsf/list/AC%2025.1529- 1A/$FILE/AC%2025.1529-1A.pdf ).
(d) Subject

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

(e) Reason

This AD was prompted by multiple reports of cracks on the forward face of the rear pressure bulkhead (RPB) web. We are issuing this AD to detect and correct cracking in RPB, which could result in reduced structural integrity and rapid decompression 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) Retained Revision to the Airworthiness Limitations (AWL) Section

This paragraph restates the requirements of paragraph (f) of AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005). For airplanes having serial numbers 7003 through 8025 inclusive, 8030, and 8034: Within 30 days after November 29, 2005 (the effective date of AD 2005–23–01), revise the Airworthiness Limitations section of the Instructions for Continued Airworthiness of the Canadair Regional Jet Maintenance Requirements Manual (MRM), Part 2, Appendix B, ‘‘Airworthiness Limitations,’’ by incorporating the information specified in AWL Number 53–61–153 of the Canadair Regional Jet Temporary Revision (TR) 2B– 2109, dated October 13, 2005, into the AWL section. Perform the applicable detailed and special detailed inspections for cracking of the aft pressure bulkhead, as specified in the TR, at the applicable compliance time specified in table 1 of this AD. Repeat the detailed inspection thereafter at intervals not to exceed 1,085 flight cycles, and repeat the special detailed inspection thereafter at intervals not to exceed 4,360 flight cycles, in accordance with the procedures specified in


### 32441 Federal Register / Vol. 77, No. 106 / Friday, June 1, 2012 / Proposed Rules

AWL Number 53–61–153, as introduced by Canadair Regional Jet TR 2B–2109, dated October 13, 2005, to Appendix B, ‘‘Airworthiness Limitations,’’ of Part 2 of the Canadair Regional Jet MRM.



### TABLE 

### 1—C OMPLIANCE 

### T IMES FOR 

### I NITIAL 

### I NSPECTIONS

As of November 29, 2005 (the effective date of AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005)): If the total flight cycles accumulated on the airplane are— Inspect before the airplane accumulates—

8,000 or fewer ..................................................... 12,000 total flight cycles. More than 8,000 but fewer than 12,000 ............. 15,000 total flight cycles or within 4,000 flight cycles after November 29, 2005 (the effective date of AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005)), whichever is first. 12,000 or more but fewer than 15,000 ............... 17,000 total flight cycles or within 3,000 flight cycles after November 29, 2005 (the effective date of AD 2005–23–01), whichever is first. 15,000 or more but fewer than 17,000 ............... 18,500 total flight cycles or within 2,000 flight cycles after November 29, 2005 (the effective date of AD 2005–23–01), whichever is first. 17,000 or more but fewer than 18,500 ............... 19,500 total flight cycles or within 1,500 flight cycles after November 29, 2005 (the effective date of AD 2005–23–01), whichever is first. 18,500 or more but fewer than 19,500 ............... 20,000 total flight cycles or within 1,000 flight cycles after November 29, 2005 (the effective date of AD 2005–23–01), whichever is first. 19,500 or more ................................................... 500 flight cycles after November 29, 2005 (the effective date of AD 2005–23–01).

(h) Retained General Revision of MRM

This paragraph restates the requirements of paragraph (g) of AD 2005–23–01, Amendment 39–14359 (70 FR 69073, November 14, 2005). For airplanes having serial numbers 7003 through 8025 inclusive, 8030, and 8034: When the information in AWL Number 53–61–153 of the Canadair Regional Jet TR 2B–2109, dated October 13, 2005, to Appendix B, ‘‘Airworthiness Limitations,’’ of Part 2 of the Canadair Regional Jet MRM, is included in the general revisions of the MRM, the general revisions may be inserted into the AWL section of the Instructions for Continued Airworthiness, and this information may be removed from the MRM.
(i) New Revision of the Maintenance Program

Within 60 days after the effective date of this AD: Revise the maintenance program by incorporating the revised inspection requirements specified in AWL Number 53– 61–153 of Bombardier TR 2B–2187, dated June 22, 2011, to Appendix B –Airworthiness Limitations, of Part 2 of the Bombardier CL– 600–2B19 MRM. The initial compliance times for the task start at the applicable time specified in paragraphs (i)(1) and (i)(2) of this AD. Doing an inspection required by paragraph (i) of this AD terminates the requirements of paragraph (g) of this AD.

(1) For airplanes that have accumulated 10,500 total flight cycles or less as of the effective date of this AD: Before the accumulation of 12,000 total flight cycles.

(2) For airplanes that have accumulated more than 10,500 total flight cycles as of the effective date of this AD: Within 1,500 flight cycles after the effective date of this AD, or at the next scheduled inspection interval for AWL Number 53–61–153, whichever occurs first.
(j) No Alternative Actions or Intervals

After accomplishing the revisions required by paragraph (i) of this AD, no alternative actions (e.g., inspections) or intervals may be used other than those specified in Canadair Regional Jet TR 2B–2109, dated October 13, 2005, to Appendix B, ‘‘Structural Airworthiness Limitations, of Part 2 of the Canadair Regional Jet MRM; and Bombardier TR 2B–2187, dated June 22, 2011, to Appendix B—Airworthiness Limitations, of Part 2 of the Bombardier CL–600–2B19 MRM; unless the actions and intervals are approved as an AMOC in accordance with the procedures specified in paragraph (k)(1) of this AD.

(k) 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 manager of 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.

(l) Related Information

Refer to MCAI Canadian Airworthiness Directive CF–2011–30, dated August 11, 2011, and the following temporary revision; for related information.

(1) Bombardier TR 2B–2187, dated June 22, 2011, to Appendix B—Airworthiness Limitations, of Part 2 of the Bombardier CL– 600–2B19 MRM.

(2) Canadair Regional Jet TR 2B–2109, dated October 13, 2005, to Appendix B, ‘‘Airworthiness Limitations,’’ of Part 2 of the Canadair Regional Jet MRM.

Issued in Renton, Washington, on May 18,
2012. Michael J. Kaszycki, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 2012–13329 Filed 5–31–12; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 121**

**[Docket No. FAA–2011–0045]**

**Proposed Legal Interpretation**

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

**ACTION :**  Proposed interpretation.

**SUMMARY :**  The FAA is considering clarifying prior legal interpretations regarding pilot in command discretion under 14 CFR 121.547(a)(3) and (a)(4).

**DATES :**  Comments must be received on or before July 31, 2012.

**ADDRESSES :**  You may send comments identified by Docket Number FAA– 2011–0045 using any of the following methods:

Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the online instructions for sending your comments electronically.