20072 Federal Register / Vol. 72, No. 77 / Monday, April 23, 2007 / Proposed Rules 

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. 

§ 39.13 [Amended] 

2. The FAA amends § 39.13 by adding 

the following new AD: 

Alpha Aviation Design Limited (Type 

Certificate No. A48EU previously held 

by APEX Aircraft and AVIONS PIERRE 

ROBIN): Docket No. FAA–2006–26494; 

Directorate Identifier 2006–CE–79–AD. 

Comments Due Date 

(a) We must receive comments by May 23, 

2007. 

Affected ADs 

(b) None. 

Applicability 

(c) This AD applies to Model R2160 

airplanes, serial numbers 001 through 378, 

certificated in any category. 

Subject 

(d) Air Transport Association of America 

(ATA) Code 57: Wings. 

Reason 

(e) The mandatory continuing 

airworthiness information (MCAI) states: 

To prevent unchecked corrosion 

developing on the wing spars due to access 

for inspections being difficult under normal 

maintenance practices, which could lead to 

an unsafe condition and possibly a 

catastrophic failure of the wing accomplish 

the following: 

The MCAI requires inspecting the visible 

parts of the spar web and the upper and 

lower boom angles (top and bottom spar 

caps) for corrosion and correcting as 

necessary. 

Actions and Compliance 

(f) Unless already done, do the following 

actions. Accomplishment of European 

Aviation Safety Agency (EASA) AD 2005–

0028 satisfies the requirement of this AD: 

(1) Within 66 months after aircraft date of 

manufacture or within 6 months after the 

effective date of this AD, whichever occurs 

later, unless already done within the last 24 

months, and thereafter at intervals not to 

exceed 24 months, remove the main landing 

gear legs and all the wing inspection panels 

following the instructions in the aircraft 

maintenance manual and inspect the visible 

parts of the spar web and the upper and 

lower boom angles (top and bottom spar 

caps), following Avions Pierre Robin Service 

Letter No. 19, dated October 1980; and 

Avions Pierre Robin Service Bulletin No. 99, 

dated June 24, 1983. If the spars are replaced, 

the inspections at intervals of 24 months 

must be resumed within 60 months from the 

date of replacement. 

(2) Before further flight, if corrosion is 

found on the rear face of the spar web or the 

upper and lower boom angles, then inspect 

the front face of the spar for corrosion 

following Avions Pierre Robin Service Letter 

No. 19, dated October 1980; and Avions 

Pierre Robin Service Bulletin No. 99, dated 

June 24, 1983. It may be necessary to cut 

inspection holes or remove the wings to 

inspect the front face of the spar. Inspection 

holes must be prepared to a manufacturerapproved repair scheme. 

(3) Before further flight, treat corrosion 

following Avions Pierre Robin Service Letter 

No. 19, dated October 1980; and Avions 

Pierre Robin Service Bulletin No. 99, dated 

June 24, 1983. 

(4) Before further flight, if corrosion is 

found which exceeds the limits specified in 

Avions Pierre Robin Service Letter No. 19, 

dated October 1980, repair following an 

approved repair scheme. 

FAA AD Differences 

Note: This AD differs from the MCAI and/ 

or service information as follows: No 

differences. 

Other FAA AD Provisions 

(g) The following provisions also apply to 

this AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, Standards Staff, 

FAA, ATTN: Karl Schletzbaum, Aerospace 

Engineer, FAA, Small Airplane Directorate, 

901 Locust, Room 301, Kansas City, Missouri 

64106; telephone: (816) 329–4146; fax: (816) 

329–4090, has the authority to approve 

AMOCs for this AD, if requested using the 

procedures found in 14 CFR 39.19. 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, 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 Civil Aviation Authority 

of New Zealand AD DCA/R2000/37A, dated 

December 21, 2006; Avions Pierre Robin 

Service Letter No. 19, dated October 1980; 

and Avions Pierre Robin Service Bulletin No. 

99, dated June 24, 1983, for related 

information. 

Issued in Kansas City, Missouri, on April 

17, 2007. 

Charles L. Smalley, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. E7–7644 Filed 4–20–07; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2007–27431; Directorate 

Identifier 2007–CE–016–AD] 

RIN 2120–AA64 

Airworthiness Directives; Stemme 

GmbH & Co. KG Models STEMME S10–

V and STEMME S10–VT Powered 

Sailplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (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) 

originated by an aviation authority of 

another country to identify and correct 

an unsafe condition on an aviation 


pwalker on PROD1PC71 with PROPOSALS
Federal Register / Vol. 72, No. 77 / Monday, April 23, 2007 / Proposed Rules 20073 

product. The MCAI describes the unsafe 

condition as: 

Service experience showed that the 

connection screw of the propeller blade 

follower type 10AP–VM may break and the 

main part of the blade follower can be lost 

in flight. This condition, if not corrected, 

could lead to high vibration during powered 

flight and consequently result in decreased 

control of the aircraft. 

Stemme has developed a new blade 

follower, Model 10AP–VP, which is 

reinforced on the shaft and has an Allen head 

screw installed instead of a slotted screw. For 

the reason stated above, this Emergency 

Airworthiness Directive (EAD) requires the 

replacement of the blade follower type 

10AP–VM with the new type 10AP–VP. 

This EAD has been revised to correct the 

TCDS reference and the applicability 

statement. No separate TC was issued for the 

affected propellers. These propellers are part 

of the aircraft type design. 

Paragraph (4) of the ‘‘Compliance’’ section 

of this EAD has been corrected. 

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 May 23, 2007. 

ADDRESSES: You may send comments by 

any of the following methods: 

• DOT Docket Web site: Go to 

http://dms.dot.gov and follow the 

instructions for sending your comments 

electronically. 

• Fax: (202) 493–2251. 

• Mail: Docket Management Facility, 

U.S. Department of Transportation, 400 

Seventh Street, SW., Nassif Building, 

Room PL–401, Washington, DC 20590–

0001. 

• Hand Delivery: Room PL–401 on 

the plaza level of the Nassif Building, 

400 Seventh Street, SW., Washington, 

DC, between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

• Federal eRulemaking Portal: Go to 

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

instructions for submitting comments. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http://dms.dot.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 

proposed AD, the regulatory evaluation, 

any comments received, and other 

information. The street address for the 

Docket Office (telephone (800) 647–

5227) is in the ADDRESSES section. 

Comments will be available in the AD 

docket shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Gregory Davison, Aerospace Engineer, 

FAA, Small Airplane Directorate, 901 

Locust, Room 301, Kansas City, 

Missouri 64106; telephone: (816) 329–

4130; fax: (816) 329–4090. 

SUPPLEMENTARY INFORMATION: 

Streamlined Issuance of AD 

The FAA is implementing a new 

process for streamlining the issuance of 

ADs related to MCAI. This streamlined 

process will allow us to adopt MCAI 

safety requirements in a more efficient 

manner and will reduce safety risks to 

the public. This process continues to 

follow all FAA AD issuance processes to 

meet legal, economic, Administrative 

Procedure Act, and Federal Register 

requirements. We also continue to meet 

our technical decision-making 

responsibilities to identify and correct 

unsafe conditions on U.S.-certificated 

products. 

This proposed AD references the 

MCAI and related service information 

that we considered in forming the 

engineering basis to correct the unsafe 

condition. The proposed AD contains 

text copied from the MCAI and for this 

reason might not follow our plain 

language principles. 

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–2007–27431; Directorate Identifier 

2007–CE–016–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 because of those 

comments. 

We will post all comments we 

receive, without change, to http:// 

dms.dot.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 

The European Aviation Safety Agency 

(EASA), which is the Technical Agent 

for the Member States of the European 

Community, has issued EASA 

Emergency AD No. 2006–0373R1–E, 

dated December 15, 2006, corrected 

January 5, 2007 (referred to after this as 

‘‘the MCAI’’), to correct an unsafe 

condition for the specified products. 

The MCAI states: 

Service experience showed that the 

connection screw of the propeller blade 

follower type 10AP–VM may break and the 

main part of the blade follower can be lost 

in flight. This condition, if not corrected, 

could lead to high vibration during powered 

flight and consequently result in decreased 

control of the aircraft. 

Stemme has developed a new blade 

follower, Model 10AP–VP, which is 

reinforced on the shaft and has an Allen head 

screw installed instead of a slotted screw. For 

the reason stated above, this Emergency 

Airworthiness Directive (EAD) requires the 

replacement of the blade follower type 

10AP–VM with the new type 10AP–VP. 

This EAD has been revised to correct the 

TCDS reference and the applicability 

statement. No separate TC was issued for the 

affected propellers. These propellers are part 

of the aircraft type design. 

Paragraph (4) of the ‘‘Compliance’’ section 

of this EAD has been corrected. 

You may obtain further information 

by examining the MCAI in the AD 

docket. 

Relevant Service Information 

Stemme GmbH & Co. KG has issued 

STEMME F & D Service Bulletin (SB) 

A31–10–078, Am.-Index: 01.a, dated 

November 6, 2006. 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 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 this State of 

Design Authority, 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 and determined the unsafe 

condition exists and is likely to exist or 

develop on other products of the same 

type design. 

Differences Between This Proposed 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 also have proposed 

different actions in this AD from those 

in the MCAI in order to follow FAA 

policies. Any such differences are 

highlighted in a note within the 

proposed AD. 

Costs of Compliance 

Based on the service information, we 

estimate that this proposed AD would 


pwalker on PROD1PC71 with PROPOSALS
20074 Federal Register / Vol. 72, No. 77 / Monday, April 23, 2007 / Proposed Rules 

affect about 53 products of U.S. registry. 

We also estimate that it would take 

about 3 work-hours per product to 

comply with the basic requirements of 

this proposed AD. The average labor 

rate is $80 per work-hour. Required 

parts would cost about $117 per 

product. Where the service information 

lists required parts costs that are 

covered under warranty, we have 

assumed that there will be no charge for 

these costs. As we do not control 

warranty coverage for affected parties, 

some parties may incur costs higher 

than estimated here. 

Based on these figures, we estimate 

the cost of the proposed AD on U.S. 

operators to be $18,921, or $357 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); 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. 

§ 39.13 [Amended] 

2. The FAA amends § 39.13 by adding 

the following new AD: 

Stemme GmbH & Co. KG Models STEMME 

S10–V and STEMME S10–VT Powered 

Sailplanes: Docket No. FAA–2007–

27431; Directorate Identifier 2007–CE–

016–AD. 

Comments Due Date 

(a) We must receive comments by May 23, 

2007. 

Affected ADs 

(b) None. 

Applicability 

(c) This AD applies to Models STEMME 

S10–V and STEMME S10–VT powered 

sailplanes, all serial numbers, certificated in 

any category. 

Subject 

(d) Air Transport Association of America 

(ATA) Code 61: Propellers. 

Reason 

(e) The mandatory continuing 

airworthiness information (MCAI) states: 

Service experience showed that the 

connection screw of the propeller blade 

follower type 10AP–VM may break and the 

main part of the blade follower can be lost 

in flight. This condition, if not corrected, 

could lead to high vibration during powered 

flight and consequently result in decreased 

control of the aircraft. 

Stemme has developed a new blade 

follower, Model 10AP–VP, which is 

reinforced on the shaft and has an Allen head 

screw installed instead of a slotted screw. For 

the reason stated above, this Emergency 

Airworthiness Directive (EAD) requires the 

replacement of the blade follower type 

10AP–VM with the new type 10AP–VP. 

This EAD has been revised to correct the 

TCDS reference and the applicability 

statement. No separate TC was issued for the 

affected propellers. These propellers are part 

of the aircraft type design. 

Paragraph (4) of the ‘‘Compliance’’ section 

of this EAD has been corrected. 

Actions and Compliance 

(f) Unless already done, within 25 engine 

operating hours or 90 days after the effective 

date of this AD, whichever occurs first, do 

the following actions: 

(1) Replace the blade follower type 10AP–

VM with the new type 10AP–VP following 

the instructions contained in STEMME F & 

D SB A31–10–078, Am.-index: 01.a, dated 

November 6, 2006. 

(2) As of 25 engine operating hours or 90 

days after the effective date of this AD, do not 

install a propeller type 10AP–F, 10AP–V or 

11AP–V on any aircraft, unless that propeller 

has the new type 10AP–VP blade follower 

installed following the instructions contained 

in STEMME F & D SB A31–10–078, Am.- 

index: 01.a, dated November 6, 2006. 

FAA AD Differences 

Note: This AD differs from the MCAI and/ 

or service information as follows: The MCAI 

requires an amendment to the aircraft flight 

manual before further flight as an interim 

requirement to the replacement. We consider 

before flight as an urgent safety of flight 

compliance time, and we do not consider this 

unsafe condition to be an urgent safety of 

flight condition. We feel that 25 engine 

operating hours or 90 days, whichever occurs 

first, for the replacement is an adequate 

compliance for this AD action and meets the 

FAA requirements of a notice of proposed 

rulemaking (NPRM). We do encourage you to 

incorporate these flight manual amendments 

referenced in the MCAI and service 

information until you replace the propeller 

blade follower. 

Other FAA AD Provisions 

(g) The following provisions also apply to 

this AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, Standards Staff, 

FAA, ATTN: Gregory Davison, Aerospace 

Engineer, FAA, Small Airplane Directorate, 

901 Locust, Room 301, Kansas City, Missouri, 

64106; telephone: (816) 329–4130; fax: (816) 

329–4090, has the authority to approve 

AMOCs for this AD, if requested using the 

procedures found in 14 CFR 39.19. 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, 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. 


pwalker on PROD1PC71 with PROPOSALS
Federal Register / Vol. 72, No. 77 / Monday, April 23, 2007 / Proposed Rules 20075 

Related Information 

(h) Refer to MCAI European Aviation 

Safety Agency (EASA) Emergency AD No.: 

2006–0373R1–E, dated December 15, 2006, 

corrected January 5, 2007; and STEMME F & 

D SB A31–10–078, Am.-index: 01.a, dated 

November 6, 2006, for related information. 

Issued in Kansas City, Missouri, on April 

17, 2007. 

Charles L. Smalley, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. E7–7642 Filed 4–20–07; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2007–27229; Directorate 

Identifier 2007–NE–03–AD] 

RIN 2120–AA64 

Airworthiness Directives; CFM 

International, S.A. CFM56–7B Series 

Turbofan Engines 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The FAA proposes to adopt a 

new airworthiness directive (AD) for 

CFM International, S.A. CFM56–7B 

Series Turbofan Engines. This proposed 

AD would require revising the 

Airworthiness Limitations Section 

(ALS) in the Engine Shop Manual (ESM) 

and the air carrier’s approved 

continuous airworthiness maintenance 

program (CAMP) to add mandatory 

inspections of certain low pressure 

turbine rear frames (TRFs) to the ALS or 

CAMP. This proposed AD results from 

a refined lifing analysis by the engine 

manufacturer that shows the need to 

identify an initial threshold for 

inspecting certain TRFs. We are 

proposing this AD to prevent failure of 

the TRF from low-cycle fatigue cracks. 

Failure of the TRF could result in 

engine separation from the airplane, 

which could lead to loss of control of 

the airplane. 

DATES: We must receive any comments 

on this proposed AD by June 22, 2007. 

ADDRESSES: Use one of the following 

addresses to comment on this proposed 

AD. 

• DOT Docket Web site: Go to 

http://dms.dot.gov and follow the 

instructions for sending your comments 

electronically. 

• Government-wide rulemaking Web 

site: Go to http://www.regulations.gov 

and follow the instructions for sending 

your comments electronically. 

• Mail: Docket Management Facility; 

U.S. Department of Transportation, 400 

Seventh Street, SW., Nassif Building, 

Room PL–401, Washington, DC 20590–

0001. 

• Fax: (202) 493–2251. 

• Hand Delivery: Room PL–401 on 

the plaza level of the Nassif Building, 

400 Seventh Street, SW., Washington, 

DC, between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

You may examine the comments on 

this proposed AD in the AD docket on 

the Internet at http://dms.dot.gov. 

FOR FURTHER INFORMATION CONTACT: 

Colleen M. D’Alessandro, Aerospace 

Engineer, Engine Certification Office, 

FAA, Engine and Propeller Directorate, 

12 New England Executive Park, 

Burlington, MA 01803; telephone (781) 

238–7133; fax (781) 238–7199. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send us any written 

relevant data, views, or arguments 

regarding this proposal. Send your 

comments to an address listed under 

ADDRESSES. Include ‘‘Docket No. FAA–

2007–27229; Directorate Identifier 

2007–NE–03–AD’’ in the subject line of 

your comments. We specifically invite 

comments on the overall regulatory, 

economic, environmental, and energy 

aspects of the proposed AD. We will 

consider all comments received by the 

closing date and may amend the 

proposed AD in light of those 

comments. 

We will post all comments we 

receive, without change, to http:// 

dms.dot.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 DOT 

Web site, anyone can find and read the 

comments in any of our dockets, 

including 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) or you may visit http:// 

dms.dot.gov. 

Examining the AD Docket 

You may examine the docket that 

contains the proposal, any comments 

received and, any final disposition in 

person at the DOT Docket Offices 

between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

The Docket Office (telephone (800) 647–

5227) is located on the plaza level of the 

Department of Transportation Nassif 

Building at the street address stated in 

ADDRESSES. Comments will be available 

in the AD docket shortly after the 

Docket Management Facility receives 

them. 

Discussion 

This AD is required because TRFs, 

part numbers 340–166–205–0, 340–166–

206–0, 340–166–207–0, 340–166–208–0, 

340–166–209–0, 340–166–210–0, now 

require an initial inspection threshold of 

25,000 cycles-in-service (CIS) on the 

commercial (air carrier) models engines 

and 19,000 CIS on the business jet 

models. This proposed AD would not 

affect any other CFM56–7B part number 

TRFs. We have been monitoring CFM’s 

revised life analysis progress since 

February 2005. CFM International 

provided to us the November 15, 2006 

revision to the ESM to introduce 

mandatory inspections of the TRF. CFM 

International has been using a damage 

tolerant lifing approach, based on an 

FAA approved methodology for 

structural lifed components, to prepare 

life extensions for all CFM56 TRFs 

using on-condition life management. 

This improved life management process 

defines a first inspection threshold and 

reinspection intervals accounting for 

crack initiation and propagation. The 

previous life management process was 

based on crack initiation only. This 

condition, if not corrected, could result 

in failure of the TRF from low-cycle 

fatigue cracks. Failure of the TRF could 

result in engine separation from the 

airplane, which could lead to loss of 

control of the airplane. 

FAA’s Determination and Requirements 

of the Proposed AD 

We have evaluated all pertinent 

information and identified an unsafe 

condition that is likely to exist or 

develop on other products of this same 

type design. We are proposing this AD, 

which would require revising the 

Airworthiness Limitations Section in 

the ESM and the air carrier’s approved 

continuing airworthiness maintenance 

program to incorporate life reductions 

for certain TRFs. 

Costs of Compliance 

We estimate that this proposed AD 

would affect 1,228 engines installed on 

airplanes of U.S. registry. Since life 

extensions are possible on condition, 

the cost of the proposed AD will be 

limited to performing TRF inspections. 

We also estimate that it would take 

about 3.0 work-hours per engine to 

perform the proposed actions, including 


pwalker on PROD1PC71 with PROPOSALS