Federal Register / Vol. 76, No. 131 / Friday, July 8, 2011 / Rules and Regulations 40219 

repair No. FRS6669 and engine manual 

repair FRS5887 as a result of a translating 

cowl gearbox stubshaft failure, the MCAI 

requires compliance before March 31, 2010. 

This AD requires compliance within 215 

cycles-in-service (CIS) after the effective date 

of this AD. 

(2) For engines on which the TRU was 

previously repaired using engine manual 

repair No. FRS5887 only, the MCAI requires 

compliance before December 31, 2012. This 

AD requires compliance within 2,225 CIS 

after the effective date of this AD. 

Other FAA AD Provisions 

Alternative Methods of Compliance 

(AMOCs) 

(i) 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 

(j) Refer to MCAI EASA Airworthiness 

Directive 2009–0253, dated November 30, 

2009, for related information. 

(k) Contact Alan Strom, Aerospace 

Engineer, Engine Certification Office, FAA, 

Engine and Propeller Directorate, 12 New 

England Executive Park, Burlington, MA 

01803; e-mail: alan.strom@faa.gov; telephone 

(781) 238–7143; fax (781) 238–7199, for more 

information about this AD. 

Material Incorporated by Reference 

(l) You must use Rolls-Royce (RR) Alert 

Service Bulletin (ASB) RB.211–78–AG084, 

Revision 5, dated February 4, 2011, to do the 

actions required by this AD, unless the AD 

specifies otherwise. 

(1) The Director of the Federal Register 

approved the incorporation by reference of 

this service information under 5 U.S.C. 

552(a) and 1 CFR part 51. 

(2) For service information identified in 

this AD, contact Rolls-Royce plc, P.O. Box 

31, Derby, DE24 8BJ, United Kingdom; 

telephone 011 44 1332 242424; fax 011 44 

1332 249936. 

(3) You may review copies at the FAA, 

New England Region, 12 New England 

Executive Park, Burlington, MA; or at the 

National Archives and Records 

Administration (NARA). For information on 

the availability of this material at NARA, call 

(202) 741–6030, or go to: http:// 

www.archives.gov/federal-register/cfr/ibrlocations.html. 

Issued in Burlington, Massachusetts, on 

June 8, 2011. 

Peter A. White, 

Acting Manager, Engine and Propeller 

Directorate, Aircraft Certification Service. 

[FR Doc. 2011–16954 Filed 7–7–11; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2011–0714; Directorate 

Identifier 2011–CE–024–AD; Amendment 

39–16744; AD 2011–14–09] 

RIN 2120–AA64 

Airworthiness Directives; Various 

Aircraft Equipped With Rotax Aircraft 

Engines 912 A Series Engine 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule; request for 

comments. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for the 

products listed above that will 

supersede an existing AD. This AD 

results from mandatory continuing 

airworthiness information (MCAI) 

issued by the aviation authority of 

another country to identify and correct 

an unsafe condition on an aviation 

product. The MCAI describes the unsafe 

condition as: 

During a production process review, a 

deviation in hardening of certain Part 

Number (P/N) 944072 washers has been 

detected, which exceeds the hardness of the 

design specification. 

The affected washers are part of the 

magneto ring flywheel hub installation and 

have been installed on a limited number of 

engines. No defective washers have been 

shipped as spare parts. 

This condition, if not corrected, could lead 

to cracks in the washer, loosening of the 

magneto flywheel hub and consequent 

ignition failure, possibly resulting in damage 

to the engine, in-flight engine shutdown and 

forced landing, damage to the aeroplane and 

injury to occupants. 

This AD requires actions that are 

intended to address the unsafe 

condition described in the MCAI. 

DATES: This AD becomes effective July 

25, 2011. 

As of June 16, 2011 (76 FR 31465, 

June 1, 2011), the Director of the Federal 

Register approved the incorporation by 

reference of Rotax Aircraft Engines 

Mandatory Service Bulletin SB–912–058 

SB–914–041, dated April 15, 2011, 

listed in this AD. 

We must receive comments on this 

AD by August 22, 2011. 

ADDRESSES: You may send comments by 

any of the following methods: 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov. Follow the 

instructions for submitting comments. 

• Fax: (202) 493–2251. 

• Mail: U.S. Department of 

Transportation, Docket Operations, 

M–30, West Building Ground Floor, 

Room W12–140, 1200 New Jersey 

Avenue, SE., Washington, DC 20590. 

• Hand Delivery: 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 BRP–Rotax GmbH & 

Co. KG, Welser Strasse 32, A–4623 

Gunskirchen, Austria; phone: +43 7246 

601 0; fax: +43 7246 601 9130; Internet: 

http://www.rotax-aircraft-engines.com. 

You may review copies of the 

referenced service information at the 

FAA, Small Airplane Directorate, 901 

Locust, Kansas City, Missouri 64106. 

For information on the availability of 

this material at the FAA, call (816) 329– 

4148. 

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 (telephone (800) 647– 

5527) is in the ADDRESSES section. 

Comments will be available in the AD 

docket shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Sarjapur Nagarajan, Aerospace Engineer, 

FAA, Small Airplane Directorate, 901 

Locust, Room 301, Kansas City, 

Missouri 64106; telephone: (816) 329– 

4145; fax: (816) 329–4090; e-mail: 

sarjapur.nagarajan@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

On May 10, 2011, we issued AD 

2011–11–03, Amendment 39–16702 (76 

FR 31465, June 1, 2011). That AD 

required actions intended to address an 

unsafe condition on the products listed 

above. 

Since we issued AD 2011–11–03, we 

determined that we inadvertently 

omitted certain airplanes equipped with 

Rotax 912 A series engines from the 

Applicability section. We have also 

determined that we included certain 

airplanes in the Applicability section 

that are not equipped with Rotax 912 A 

series engines. 

Relevant Service Information 

Rotax Aircraft Engines has issued 

Mandatory Service Bulletin SB–912–058 

and SB–914–041 (same document), 


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40220 Federal Register / Vol. 76, No. 131 / Friday, July 8, 2011 / Rules and Regulations 

dated April 15, 2011. The actions 

described in this service information are 

intended to correct the unsafe condition 

identified in the MCAI. 

FAA’s Determination and Requirements 

of the 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 this State of 

Design Authority, they have notified us 

of the unsafe condition described in the 

MCAI and service information 

referenced above. We are issuing this 

AD because we evaluated all 

information provided by the State of 

Design Authority and determined the 

unsafe condition exists and is likely to 

exist or develop on other products of the 

same type design. 

Differences Between This AD and the 

MCAI or Service Information 

We have reviewed the MCAI and 

related service information and, in 

general, agree with their substance. But 

we might have found it necessary to use 

different words from those in the MCAI 

to ensure the AD is clear for U.S. 

operators and is enforceable. In making 

these changes, we do not intend to differ 

substantively from the information 

provided in the MCAI and related 

service information. 

We might have also required different 

actions in this AD from those in the 

MCAI in order to follow FAA policies. 

Any such differences are described in a 

separate paragraph of the AD. These 

requirements take precedence over 

those copied from the MCAI. 

FAA’s 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 cracks in the washer of the 

magneto ring flywheel hub could cause 

loosening of the magneto flywheel hub. 

This failure could result in ignition 

failure and/or damage to the engine, 

causing in-flight engine shutdown 

leading to a forced landing. A forced 

landing could result in damage to the 

airplane and injury to the occupants. 

Therefore, we determined that notice 

and opportunity for public comment 

before issuing this AD are impracticable 

and that good cause exists for making 

this amendment effective in fewer than 

30 days. 

Comments Invited 

This AD is a final rule that involves 

requirements affecting flight safety, and 

we did not precede it by notice and 

opportunity for public comment. We 

invite you to send any written relevant 

data, views, or arguments about this AD. 

Send your comments to an address 

listed under the ADDRESSES section. 

Include ‘‘Docket No. FAA–2011–0714; 

Directorate Identifier 2011–CE–024– 

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. 

Costs of Compliance 

We estimate that this AD will affect 

112 products of U.S. registry. We also 

estimate that it would take about 24 

work-hours per product to comply with 

the basic requirements of this AD. The 

average labor rate is $85 per work-hour. 

Required parts would cost about $20 per 

product. 

Based on these figures, we estimate 

the cost of the AD on U.S. operators to 

be $230,720, or $2,060 per product. 

According to the manufacturer, some 

of the costs of this AD may be covered 

under warranty, thereby reducing the 

cost impact on affected individuals. We 

do not control warranty coverage for 

affected individuals. As a result, we 

have included all costs in our cost 

estimate. 

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 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); 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 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 

removing Amendment 39–16702 (76 FR 

31465, June 1, 2011), and adding the 

following new AD: 

2011–14–09 Various Aircraft: Amendment 

39–16744; Docket No. FAA–2011–0714; 

Directorate Identifier 2011–CE–024–AD. 

Effective Date 

(a) This airworthiness directive (AD) 

becomes effective July 25, 2011. 

Affected ADs 

(b) This AD supersedes AD 2011–11–03; 

Amendment 39–16702. 

Applicability 

(c) This AD applies to all serial numbers 

of the following aircraft, equipped with a 

Rotax Aircraft Engines 912 A series engine, 


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Federal Register / Vol. 76, No. 131 / Friday, July 8, 2011 / Rules and Regulations 40221 

serial number 4,410.888 through 4,410.899, 

installed and certificated in any category: 

GROUP 1 AIRPLANES

[airplanes previously affected by AD 2011–11–03] 

Type certificate holder Aircraft model Engine model 

Aeromot-Indu ́stria Mecaˆnico-Metalu ́rgica Ltda ........................................................... AMT–200 ................................................. 912 A2. 

Diamond Aircraft Industries ........................................................................................ HK 36 R ‘‘SUPER DIMONA’’ .................. 912 A. 

Diamond Aircraft Industries Inc. ................................................................................. DA20–A1 ................................................. 912 A3. 

HOAC–Austria ............................................................................................................ DV 20 KATANA ....................................... 912 A3. 

Iniziative Industriali Italiane S.p.A. .............................................................................. Sky Arrow 650 TC ................................... 912 A2. 

SCHEIBE–Flugzeugbau GmbH .................................................................................. SF 25C .................................................... 912 A2. 

GROUP 2 AIRPLANES

[airplanes not previously affected by AD 2011–11–03] 

Type certificate holder Aircraft model Engine model 

DIAMOND AIRCRAFT INDUSTRIES GmbH ............................................................. HK 36 TS and HK 36 TC ........................ 912 A3. 

Subject 

(d) Air Transport Association of America 

(ATA) Code 74: Ignition. 

Reason 

(e) The mandatory continuing 

airworthiness information (MCAI) states: 

During a production process review, a 

deviation in hardening of certain Part 

Number (P/N) 944072 washers has been 

detected, which exceeds the hardness of the 

design specification. 

The affected washers are part of the 

magneto ring flywheel hub installation and 

have been installed on a limited number of 

engines. No defective washers have been 

shipped as spare parts. 

This condition, if not corrected, could lead 

to cracks in the washer, loosening of the 

magneto flywheel hub and consequent 

ignition failure, possibly resulting in damage 

to the engine, in-flight engine shutdown and 

forced landing, damage to the aeroplane and 

injury to occupants. 

For the reasons described above, this AD 

requires, for the affected engines, the 

replacement of the P/N 944072 washer and 

associated gasket ring P/N 950141 with 

serviceable parts, having the same P/N. 

This AD also prohibits installation of an 

affected engine on an aeroplane, unless the 

washer on that engine has been replaced as 

required by this AD. 

Actions and Compliance 

(f) Unless already done, do the following 

actions: 

(1) Replace washer, part number (P/N) 

944072, and associated gasket ring, P/N 

950141, on the magneto ring flywheel hub 

with FAA-approved serviceable parts with 

the same P/Ns. Do the replacements 

following the Accomplishment Instructions 

in Rotax Aircraft Engines Mandatory Service 

Bulletin SB–912–058 and SB–914–041 (same 

document), dated April 15, 2011. 

(i) For Group 1 airplanes (airplanes 

previously affected by AD 2011–11–03): 

Within the next 10 hours time-in-service 

(TIS) after June 16, 2011 (the effective date 

retained from AD 2011–11–03) or within 4 

months after June 16, 2011 (the effective date 

retained from AD 2011–11–03), whichever 

occurs first. 

(ii) For Group 2 airplanes (airplanes not 

previously affected by AD 2011–11–03): 

Within the next 10 hours TIS after July 25, 

2011 (the effective date of this AD) or within 

4 months after July 25, 2011 (the effective 

date of this AD), whichever occurs first. 

(2) Do not install a Rotax Aircraft Engines 

912 A series engine listed in paragraph (c) of 

this AD unless the washer, P/N 944072, and 

the gasket ring, P/N 950141, have been 

replaced as required in paragraph (f)(1) of 

this AD. 

(i) For Group 1 airplanes (airplanes 

previously affected by AD 2011–11–03): As of 

June 16, 2011 (the effective date retained 

from AD 2011–11–03). 

(ii) For Group 2 airplanes (airplanes not 

previously affected by AD 2011–11–03): As of 

July 25, 2011 (the effective date of this AD). 

FAA AD Differences 

Note: This AD differs from the MCAI and/ 

or service information as follows: EASA AD 

2011–0067–E, dated April 15, 2011, requires 

returning the removed P/N 944072 to Rotax 

Aircraft Engines. We are not requiring this 

because FAA regulation, specifically 14 CFR 

43.10, already requires disposition of 

unairworthy parts. 

Other FAA AD Provisions 

(g) The following provisions also apply to 

this AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, Standards Office, 

FAA, has the authority to approve AMOCs 

for this AD, if requested using the procedures 

found in 14 CFR 39.19. Send information to 

Attn: Sarjapur Nagarajan, Aerospace 

Engineer, FAA, Small Airplane Directorate, 

901 Locust, Room 301, Kansas City, Missouri 

64106; telephone: (816) 329–4145; fax: (816) 

329–4090. Before using any approved AMOC 

on any airplane to which the AMOC applies, 

notify your appropriate principal inspector 

(PI) in the FAA Flight Standards District 

Office (FSDO), or lacking a PI, your local 

FSDO. 

(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. 

(3) Reporting Requirements: For any 

reporting requirement in this AD, a federal 

agency may not conduct or sponsor, and a 

person is not required to respond to, nor 

shall a person be subject to a penalty for 

failure to comply with a collection of 

information subject to the requirements of 

the Paperwork Reduction Act unless that 

collection of information displays a current 

valid OMB Control Number. The OMB 

Control Number for this information 

collection is 2120–0056. Public reporting for 

this collection of information is estimated to 

be approximately 5 minutes per response, 

including the time for reviewing instructions, 

completing and reviewing the collection of 

information. All responses to this collection 

of information are mandatory. Comments 

concerning the accuracy of this burden and 

suggestions for reducing the burden should 

be directed to the FAA at: 800 Independence 

Ave., SW., Washington, DC 20591, Attn: 

Information Collection Clearance Officer, 

AES–200. 

Related Information 

(h) Refer to MCAI European Aviation 

Safety Agency (EASA) AD No. 2011–0067–E, 

dated April 15, 2011, and Rotax Aircraft 

Engines Mandatory Service Bulletin SB–912– 

058 and SB–914–041 (same document), dated 

April 15, 2011, for related information. 

Material Incorporated by Reference 

(i) You must use Rotax Aircraft Engines 

Mandatory Service Bulletin SB–912–058 SB– 

914–041, dated April 15, 2011, to do the 

actions required by this AD, unless the AD 

specifies otherwise. 

(1) On June 16, 2011 (76 FR 31465, June 

1, 2011), the Director of the Federal Register 

previously approved the incorporation by 


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reference of Rotax Aircraft Engines 

Mandatory Service Bulletin SB–912–058 SB– 

914–041, dated April 15, 2011. 

(2) For service information identified in 

this AD, contact BRP-Rotax GmbH & Co. KG, 

Welser Strasse 32, A–4623 Gunskirchen, 

Austria; phone: +43 7246 601 0; fax: +43 

7246 601 9130; Internet: http://www.rotaxaircraft-engines.com. 

(3) You may review copies of the 

referenced service information at the FAA, 

Small Airplane Directorate, 901 Locust, 

Kansas City, Missouri 64106. For information 

on the availability of this material at the 

FAA, call (816) 329–4148. 

(4) You may also review copies of the 

service information incorporated by reference 

for this AD at the National Archives and 

Records Administration (NARA). For 

information on the availability of this 

material at NARA, call (202) 741–6030, or go 

to: http://www.archives.gov/federal_register/ 

code_of_federal_regulations/ 

ibr_locations.html. 

Issued in Kansas City, Missouri, on July 1, 

2011. 

Earl Lawrence, 

Manager, Small Airplane Directorate, Aircraft 

Certification Service. 

[FR Doc. 2011–17144 Filed 7–7–11; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2011–0115; Directorate 

Identifier 2010–NE–40–AD; Amendment 39– 

16728; AD 2011–13–05] 

RIN 2120–AA64 

Airworthiness Directives; Turbomeca 

S.A. ARRIEL 2B and 2B1 Turboshaft 

Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for the 

products listed above. 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. The MCAI describes the unsafe 

condition as: 

Several cases of Gas Generator (GG) 

Turbine Blade rupture occurred in service on 

ARRIEL 2 twin engine applications and 

recently one on a single engine helicopter. 

For the case occurring in flight on a single 

engine helicopter (ARRIEL 2B1 engine), the 

pilot performed an emergency autorotation, 

landing the helicopter without further 

incident. 

We are issuing this AD to prevent 

rupture of a GG turbine blade, which 

could result in an uncommanded inflight shutdown and an emergency 

autorotation landing or accident. 

DATES: This AD becomes effective 

August 12, 2011. The Director of the 

Federal Register approved the 

incorporation by reference of a certain 

publication listed in this AD as of 

August 12, 2011. 

ADDRESSES: The Docket Operations 

office is located at Docket Management 

Facility, U.S. Department of 

Transportation, 1200 New Jersey 

Avenue, SE., West Building Ground 

Floor, Room W12–140, Washington, DC 

20590–0001. 

FOR FURTHER INFORMATION CONTACT: Rose 

Len, Aerospace Engineer, Engine 

Certification Office, FAA, Engine & 

Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

e-mail: rose.len@faa.gov; phone: (781) 

238–7772; fax (781) 238–7199. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to include an AD that would 

apply to the specified products. That 

NPRM was published in the Federal 

Register on February 18, 2011 (76 FR 

9515). That NPRM proposed to correct 

an unsafe condition for the specified 

products. The MCAI states: 

Several cases of Gas Generator (GG) 

Turbine Blade rupture occurred in service on 

ARRIEL 2 twin engine applications and 

recently one on a single engine helicopter. 

For the case occurring in flight on a single 

engine helicopter (ARRIEL 2B1 engine), the 

pilot performed an emergency autorotation, 

landing the helicopter without further 

incident. 

The design of ARRIEL 2 engines 

(containment shield around the GG turbine) 

allows debris from a blade or the disc interblade area to be contained in the event of 

rupture. However, the rupture of a GG 

Turbine Blade may lead to an uncommanded 

In Flight Shut-Down which, on a singleengine helicopter, could ultimately lead to an 

emergency autorotation landing. 

The most probable root cause of the 

ruptures is an excitation of one of the 

vibration modes of the GG Turbine Blade in 

conjunction with several secondary 

contributing factors which are deemed 

sufficient to reduce the stress margin of the 

blade to a level consistent with the rate of 

occurrences of ruptures encountered. 

Turbome ́ca has released TU166 

modification which consists in inserting 

Blade dampers between the GG Turbine Disc 

and the GG Turbine Blade platform. 

Introduction of these dampers minimizes the 

effects of HP blade vibratory excitation and 

increases the blade tolerance for this type of 

stress. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

received no comments on the NPRM. 

Conclusion 

We reviewed the available data and 

determined that air safety and the 

public interest require adopting the AD 

as proposed. 

Costs of Compliance 

Based on the service information, we 

estimate that this AD would affect about 

537 products of U.S. registry. We also 

estimate that it would take about 60 

work-hours per product to comply with 

this AD. The average labor rate is $85 

per work-hour. Required parts would 

cost about $3,900 per product. Based on 

these figures, we estimate the cost of the 

AD on U.S. operators to be $4,833,000. 

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 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 AD: 

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 


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