61168 Federal Register / Vol. 78, No. 192 / Thursday, October 3, 2013 / Rules and Regulations 

required by this AD if it is approved by the 

Boeing Commercial Airplanes Organization 

Designation Authorization (ODA) that has 

been authorized by the Manager, Seattle 

ACO, to make those findings. For a repair 

method to be approved, the repair must meet 

the certification basis of the airplane, and the 

approval must specifically refer to this AD. 

(o) Related Information 

(1) For more information about this AD, 

contact Berhane Alazar, Aerospace Engineer, 

Airframe Branch, ANM–120S, FAA, Seattle 

Aircraft Certification Office (ACO), 1601 Lind 

Avenue SW., Renton, Washington 98057– 

3356; phone: 425–917–6577; fax: 425–917– 

6590; email: berhane.alazar@faa.gov. 

(2) Service information identified in this 

AD that is not incorporated by reference in 

this AD may be obtained at the addresses 

specified in paragraphs (p)(3) and (p)(4) of 

this AD. 

(p) Material Incorporated by Reference 

(1) The Director of the Federal Register 

approved the incorporation by reference 

(IBR) of the service information listed in this 

paragraph under 5 U.S.C. 552(a) and 1 CFR 

part 51. 

(2) You must use this service information 

as applicable to do the actions required by 

this AD, unless the AD specifies otherwise. 

(i) Boeing Service Bulletin 767–32A0227, 

Revision 1, dated September 13, 2012. 

(ii) Reserved. 

(3) For service information identified in 

this AD, contact Boeing Commercial 

Airplanes, Attention: Data & Services 

Management, P.O. Box 3707, MC 2H–65, 

Seattle, Washington 98124–2207; telephone 

206–544–5000, extension 1; fax 206–766– 

5680; Internet https://

www.myboeingfleet.com. 

(4) You may view this service information 

at Transport Airplane Directorate, 1601 Lind 

Avenue SW., Renton, Washington. For 

information on the availability of this 

material at the FAA, call 425–227–1221. 

(5) You may view this service information 

that is incorporated by reference 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 Renton, Washington, on 

September 16, 2013. 

Ross Landes, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2013–23898 Filed 10–2–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2013–0052; Directorate 

Identifier 2013–NE–02–AD; Amendment 39– 

17600; AD 2013–19–18] 

RIN 2120–AA64 

Airworthiness Directives; Rolls-Royce 

plc Turbofan Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for all 

Rolls-Royce plc (RR) RB211–535E4–37, 

RB211–535E4–B–37, RB211–535E4–C– 

37, and RB211–535E4–B–75 turbofan 

engines. This AD requires removal of 

affected parts using a drawdown plan. 

This AD was prompted by RR updating 

the low-cycle-fatigue life analysis for the 

low pressure turbine (LPT) stage 2 discs. 

We are issuing this AD to prevent LPT 

stage 2 disc failure, which could result 

in uncontained engine damage and 

damage to the airplane. 

DATES: This AD becomes effective 

November 7, 2013. The Director of the 

Federal Register approved the 

incorporation by reference of certain 

publications listed in this AD as of 

November 7, 2013. 

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. 

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 AD, the mandatory 

continuing airworthiness information 

(MCAI), the regulatory evaluation, any 

comments received, and other 

information. The street address for the 

Docket Operations office (phone: 800– 

647–5527) is provided in the ADDRESSES

section. Comments will be available in 

the AD docket shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Robert Green, Aerospace Engineer, 

Engine Certification Office, FAA, Engine 

& Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

phone: 781–238–7754; fax: 781–238– 

7199; email: Robert.Green@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 by adding an AD that would 

apply to the specified products. The 

NPRM was published in the Federal 

Register on April 5, 2013 (78 FR 20507). 

The NPRM proposed to correct an 

unsafe condition for the specified 

products. The MCAI states: 

A recent re-evaluation of Critical Part lives 

carried out by Rolls-Royce revealed changes 

to the thermal profile and stresses in certain 

features of the low pressure turbine (LPT) 

Stage 2 disc. These changes have resulted in 

a reduction of the cyclic life of the LPT stage 

2 discs. 

Operation of an engine equipped with a 

Critical Part that has exceeded its cyclic life 

may result in Critical Part failure, consequent 

release of high energy debris, damage to the 

aeroplane and/or injury to occupants. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

considered the comments received. 

Agreement With the AD 

The Boeing Company expressed 

support for the NPRM (78 FR 20507, 

dated April 5, 2013). 

Request To Be Less Specific About 

Service Bulletin Revision Level and 

Date 

Texas Aero Engine Services LLC and 

United Airlines (UAL) requested that we 

not include the revision level and date 

of RR Alert Non-Modification Service 

Bulletin (NMSB) No. RB.211–72– 

AH029, dated December 13, 2012, or 

that we add the words ‘‘or later 

revision’’ because service bulletins can 

be revised often. 

We disagree. RR Alert NMSB No. 

RB.211–72–AH029, dated December 13, 

2012, contains unique methods that 

require incorporation by reference, 

requiring that we specify revision level 

and date. We do not know how the 

NMSB may be revised in the future, and 

therefore cannot add the words ‘‘or later 

revision.’’ We did not change this AD. 

Request To Change the Definition of 

Engine Shop Visit (ESV) 

RR and UAL requested that we change 

our definition of ESV in paragraph (g) of 

this AD by replacing the words 

‘‘separation of flanges’’ with ‘‘deblading 

of the affected rotor disc.’’ They noted 

that our ESV definition is not consistent 

with the instructions in RR Alert NMSB 

No. RB.211–72–AH029, dated December 

13, 2012, which only applies when the 

LPT Module will be stripped and the 

affected rotor is debladed. Our ESV 


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Federal Register / Vol. 78, No. 192 / Thursday, October 3, 2013 / Rules and Regulations 61169 

definition will result in removal of parts 

earlier than would occur using the RR 

NMSB. RR noted that this is 

unnecessary based on their risk 

assessment of a possible failure. In a 

subsequent comment, RR asked that the 

ESV definition be based on the 

deblading of the high pressure turbine 

disc since this better defines an engine 

refurbishment shop visit. 

We disagree. We defined ESV as the 

separation of a pair of major mating 

engine module flanges in order to satisfy 

our safety concerns while minimizing 

the impact to the public. We have 

determined that corrective actions can 

be practicably implemented at next ESV 

and that these actions will provide an 

acceptable level of safety. We did not 

change this AD. 

Request To Exempt an External 

Gearbox Removal From the ESV 

Definition 

RR requested that we clarify that the 

separation of a pair of major mating 

engine module flanges in paragraph (g) 

of this AD does not include the 

separation of an engine external gearbox 

from the engine, which would not 

constitute a refurbishment shop visit. 

We agree. We changed paragraph (g) 

of this AD to state: ‘‘For the purpose of 

this AD, an ESV is whenever engine 

maintenance performed prior to 

reinstallation requires the separation of 

a pair of major mating engine module 

flanges. Separation of flanges solely for 

the purpose of shipment without 

subsequent internal maintenance is not 

an ESV. Separation of the external 

gearbox engine mating flanges or 

removal of the external gearbox is also 

not classified as a shop visit.’’ 

Request To Delay Implementation of 

Reduced Rotating Parts Life Limits 

American Airlines (AAL), FedEx 

Express, and RR asked that we revise or 

remove paragraph (e)(2) of this AD to 

eliminate the requirement to assign the 

reduced maximum approved lives 

within 30 days of the effective date of 

this AD and allow the current lives as 

published in the Time Limits Manual 

(TLM) to remain in effect until 

November 30, 2016. AAL stated that the 

AD requirement will cause problems for 

operator life limit tracking systems, 

causing confusion and possibly the 

grounding of aircraft. Operator life limit 

tracking systems prevent the operation 

of parts beyond their maximum 

approved lives. 

We disagree. Operating beyond the 

redefined, reduced cyclic life limits 

represents an unsafe condition. LPT 

stage 2 discs that exceed the reduced 

life limits should be removed from 

service as soon as practicable to correct 

an unsafe condition. We did not change 

this AD. 

Request To Clarify Wording Regarding 

Compliance Date and Life Limits 

AAL and RR requested that we clarify 

wording in paragraph (e)(4) of this AD 

regarding removal of affected parts by 

the compliance date, and that the parts 

cannot exceed current life limits. AAL 

stated that this paragraph could 

potentially allow parts to operate 

beyond both the current and reduced 

life limits. 

We partially agree. We agree that 

paragraph (e)(4) of this AD could be 

misinterpreted because we did not 

specify that paragraph (e)(3) of this AD 

applies to those engines which have an 

engine shop visit prior to reaching the 

reduced life. 

We do not agree that the compliance 

wording could potentially allow parts to 

operate beyond their current life limits 

because the TLM limits for the RR 

RB211 engine cannot be exceeded. 

We changed paragraph (e)(3) of this 

AD by inserting ‘‘before reaching the 

part life assigned in paragraph (e)(2)’’. 

The paragraph now reads: ‘‘(3) After the 

effective date of this AD, for engines 

that have an engine shop visit (ESV) 

before reaching the part life assigned in 

paragraph (e)(2) of this AD, remove the 

LPT stage 2 disc from service before the 

part exceeds the part life assigned in 

paragraph (e)(2).’’ 

Request To Change Compliance To Be 

Consistent With the RR Alert NMSB 

AAL, RR, and UAL requested that we 

change the compliance to be consistent 

with RR Alert NMSB No. RB.211–72– 

AH029, dated December 13, 2012. This 

AD requires that the reduced life limits 

be assigned within 30 days after the 

effective date of the AD. The RR Alert 

NMSB establishes that these lives are 

provisional lives, and that the current 

lives as published in the TLM remain in 

effect until November 30, 2016. AAL 

and RR noted that the risk assessment 

conducted by RR supports the 

continued use of the current life limits 

for parts not exposed during a shop visit 

and demonstrated an acceptable level of 

safety. AAL noted that the AD as 

proposed (78 FR 20507, April 5, 2013) 

will result in significant shop visit costs 

in comparison to the shop visit costs 

associated with the RR Alert NMSB. 

We disagree. The redefined, reduced 

cyclic life limits are needed to correct 

an unsafe condition. We have 

determined that corrective actions can 

be practicably implemented at next ESV 

and that these actions will provide an 

acceptable level of safety. We did not 

change this AD. 

Request To Change Compliance Time 

UAL requested that we change the 

compliance time in paragraphs (e)(1) 

and (e)(2) of this AD from ‘‘within 30 

days’’ to ‘‘within 90 days’’ because for 

UAL’s fleet of 137 engines, 30 days is 

too short of a compliance period. 

We disagree. The recommended 

timeframe for completion in RR Alert 

NMSB No. RB.211–72–AH029, dated 

December 13, 2012, was 6 weeks. The 

new lives of the LPT stage 2 discs could 

have been recalculated starting from 

when the NMSB was issued. In 

addition, the effective date of this AD is 

35 days after the date of publication in 

the Federal Register, which provides 

additional time beyond the 30 days 

mandated in this AD. We did not 

change this AD. 

Request To Change the Costs of 

Compliance 

AAL requested that we change the 

costs of compliance to include the labor 

costs associated with replacing the parts 

at an ESV (i.e., engine disassembly 

costs). AAL states that the AD requires 

replacement of parts in modules that are 

not related to an engine removal cause, 

which will result in additional labor 

costs to access and replace those parts. 

We disagree. We consider the actual 

costs of this AD, which are associated 

with the prorated reduction in the lives 

of the life-limited parts. We do not 

consider the engine disassembly costs 

that will vary depending on the category 

of the ESV. We did not change this AD. 

Comment That the European Aviation 

Safety Agency (EASA) AD Referred to 

in the NPRM Has Been Superseded 

RR commented that EASA AD 2012– 

0266, dated December 18, 2012, referred 

to in this AD, has been superseded. 

We disagree. EASA AD 2012–0266 is 

not superseded. We did not change this 

AD. 

Conclusion 

We reviewed the available data, 

including the comments received, and 

determined that air safety and the 

public interest require adopting this AD 

with the changes described previously. 

We determined that these changes will 

not increase the economic burden on 

any operator or increase the scope of 

this AD. 

Costs of Compliance 

We estimate that this AD would affect 

about 220 engines installed on airplanes 

of U.S. registry. The average labor rate 

is $85 per hour. We do not estimate any 


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61170 Federal Register / Vol. 78, No. 192 / Thursday, October 3, 2013 / Rules and Regulations 

labor cost associated with this AD 

because the affected parts are replaced 

during scheduled shop visits. Prorated 

cost of the parts adjusted for lost life is 

about $8,290 per engine. Based on these 

figures, we estimate the cost of the AD 

on U.S. operators to be $1,823,800. 

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), 

(3) Will not affect intrastate aviation 

in Alaska to the extent that it justifies 

making a regulatory distinction, 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 airworthiness 

directive (AD): 

2013–19–18 Rolls-Royce plc: Amendment 

39–17600; Docket No. FAA–2013–0052; 

Directorate Identifier 2013–NE–02–AD. 

(a) Effective Date 

This AD becomes effective November 7, 

2013. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to all Rolls-Royce plc (RR) 

RB211–535E4–37, RB211–535E4–B–37, 

RB211–535E4–C–37, and RB211–535E4–B– 

75 turbofan engines. 

(d) Unsafe Condition 

This AD was prompted by RR updating the 

low-cycle-fatigue life analysis for the low 

pressure turbine (LPT) stage 2 discs. We are 

issuing this AD to prevent LPT stage 2 disc 

failure, which could result in uncontained 

engine damage and damage to the airplane. 

(e) Actions and Compliance 

(1) Within 30 days after the effective date 

of this AD, re-calculate the cyclic life since 

new of each LPT stage 2 disc. Use the part 

lives and prorated life formulas in 

Appendices 1, 2, and 3 of RR Alert NonModification Service Bulletin (NMSB) No. 

RB.211–72–AH029, dated December 13, 

2012, to make that calculation. 

(2) Assign the Maximum Approved Lives 

defined in Appendix 1 of Alert NMSB No. 

RB.211–72–AH029, dated December 13, 

2012, to the LPT stage 2 disc based on the 

flight profile that will be flown. 

(3) After the effective date of this AD, for 

engines that have an engine shop visit (ESV), 

before reaching the part life assigned in 

paragraph (e)(2) of this AD, remove the LPT 

stage 2 disc from service before the part 

exceeds the part life assigned in paragraph 

(e)(2). 

(4) For those engines that do not have an 

ESV after the effective date of this AD before 

the part exceeds the part life assigned in 

paragraph (e)(2) of this AD, remove the part 

from service at the next ESV. 

(f) Installation Prohibition 

Except for parts that have been reworked 

using RR Service Bulletin No. RB.211–72– 

D365, Revision 5, dated December 13, 2012, 

after the effective date of this AD, do not 

reinstall any part removed per this AD into 

any engine. 

(g) Definition 

For the purpose of this AD, an ESV is 

whenever engine maintenance performed 

prior to reinstallation requires the separation 

of a pair of major mating engine module 

flanges. Separation of flanges solely for the 

purpose of shipment without subsequent 

internal maintenance is not an ESV. 

Separation of the external gearbox engine 

mating flanges or removal of the external 

gearbox is also not classified as a shop visit. 

(h) Alternative Methods of Compliance 

(AMOCs) 

The Manager, Engine Certification Office, 

FAA, may approve AMOCs to this AD. Use 

the procedures found in 14 CFR 39.19 to 

make your request. 

(i) Related Information 

(1) For more information about this AD, 

contact Robert Green, Aerospace Engineer, 

Engine Certification Office, FAA, Engine & 

Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

phone: 781–238–7754; fax: 781–238–7199; 

email: Robert.Green@faa.gov. 

(2) Refer to European Aviation Safety 

Agency Airworthiness Directive 2012–0266, 

dated December 18, 2012 for more 

information. You may examine the AD on the 

Internet at http://www.regulations.gov/

#!documentDetail;D=FAA-2013-0052-0004. 

(j) Material Incorporated by Reference 

(1) The Director of the Federal Register 

approved the incorporation by reference 

(IBR) of the service information listed in this 

paragraph under 5 U.S.C. 552(a) and 1 CFR 

part 51. 

(2) You must use this service information 

as applicable to do the actions required by 

this AD, unless the AD specifies otherwise. 

(i) RR Alert Non-Modification Service 

Bulletin (NMSB) No. RB.211–72–AH029, 

dated December 13, 2012. 

(ii) Reserved. 

(3) For Rolls-Royce plc service information 

identified in this AD, contact Rolls-Royce 

plc, Corporate Communications, P.O. Box 31, 

Derby, England, DE248BJ; phone: 011–44– 

1332–242424; fax: 011–44–1332–249936; 

email: http://www.rolls-royce.com/contact/

civil_team.jsp; or download from https://

www.aeromanager.com. 

(4) You may view this service information 

at 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. 

(5) You may view this service information 

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. 


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Federal Register / Vol. 78, No. 192 / Thursday, October 3, 2013 / Rules and Regulations 61171 

Issued in Burlington, Massachusetts, on 

September 16, 2013. 

Carlos A. Pestana, 

Acting Directorate Assistant Manager, Engine 

& Propeller Directorate, Aircraft Certification 

Service. 

[FR Doc. 2013–23448 Filed 10–2–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2013–0029; Directorate 

Identifier 2013–NE–01–AD; Amendment 39– 

17599; AD 2013–19–17] 

RIN 2120–AA64 

Airworthiness Directives; Rolls-Royce 

plc Turbofan Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for all 

Rolls-Royce plc (RR) RB211–535E4–B– 

37 series turbofan engines. This AD 

requires removal of affected parts using 

a drawdown plan. This AD was 

prompted by recalculating the lives of 

certain rotating life limited parts (LLPs) 

operated to certain flight profiles. We 

are issuing this AD to prevent the failure 

of rotating LLPs, which could result in 

uncontained failure of the engine and 

damage to the airplane. 

DATES: This AD becomes effective 

November 7, 2013. The Director of the 

Federal Register approved the 

incorporation by reference of certain 

publications listed in this AD as of 

November 7, 2013. 

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. 

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 AD, the mandatory 

continuing airworthiness information 

(MCAI), regulatory evaluation, any 

comments received, and other 

information. The street address for the 

Docket Operations office (phone: 800– 

647–5527) is provided in the ADDRESSES

section. Comments will be available in 

the AD docket shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Robert Green, Aerospace Engineer, 

Engine Certification Office, FAA, Engine 

& Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

phone: 781–238–7754; fax: 781–238– 

7199; email: robert.green@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 by adding an AD that would 

apply to the specified products. The 

NPRM was published in the Federal 

Register on April 5, 2013 (78 FR 20509). 

The NPRM proposed to correct an 

unsafe condition for the specified 

products. The MCAI states: 

Flight Profiles (FP) define the limits of 

engine operation within which the engine 

will qualify for use of an associated set of 

Critical Parts life limits. The Rolls-Royce 

RB211–535E4–B–37 engine previously had 

only one such FP and associated set of life 

limits published in the applicable RR Time 

Limits Manual. 

However, a recent review of operational 

flight data has revealed that some engines 

may have been operated beyond the currently 

valid datum FP. 

Failure to account for the correct rate of 

fatigue damage associated with engine 

operation may lead to Critical Parts failure, 

possibly resulting in release of high energy 

debris, damage to the aeroplane and/or injury 

to occupants. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

considered the comments received. 

Agreement With the AD 

The Boeing Company expressed 

support for the NPRM (78 FR 20509, 

dated April 5, 2013). 

Request To Be Less Specific About 

Service Bulletin Revision Level and 

Date 

Texas Aero Engine Service LLC, RR, 

and United Airlines (UAL) requested 

that we not include the revision level 

and date of RR Alert Non-Modification 

Service Bulletin (NMSB) No. RB.211– 

72–AG875, or that we add the words ‘‘or 

later revision’’ because service bulletins 

can be revised often. 

We disagree. RR Alert NMSB No. 

RB.211–72–AG875, dated December 13, 

2012, contains unique methods that 

require incorporation by reference, 

requiring that we specify revision level 

and date. We do not know how the 

NMSB may be revised in the future, and 

therefore cannot add the words ‘‘or later 

revision.’’ We did not change this AD. 

Request To Change the Definition of 

Engine Shop Visit (ESV) 

RR and UAL requested that we change 

our definition of ESV in paragraph (g) of 

this AD by replacing the words 

‘‘separation of flanges’’ with ‘‘deblading 

of the affected rotor disc.’’ They noted 

that our definition of ESV is not 

consistent with the instructions in RR 

Alert NMSB No. RB.211–72–AG875, 

dated December 13, 2012, which only 

applies when the rotor is debladed. Our 

ESV definition will result in the 

removal of parts earlier than would 

occur using the RR NMSB. RR noted 

that this is not necessary based on their 

risk assessment of a possible failure. In 

a subsequent comment, RR asked that 

the ESV definition be based on the 

deblading of the high pressure turbine 

disc since this better defines an engine 

refurbishment shop visit. 

We disagree. We defined ESV as the 

separation of a pair of major mating 

engine module flanges in order to satisfy 

our safety concerns while minimizing 

the impact to the public. The redefined, 

reduced cyclic life limits are needed to 

correct an unsafe condition. We have 

determined that corrective actions can 

be practicably implemented at next ESV 

and that these actions will provide an 

acceptable level of safety. We did not 

change this AD. 

Request To Exempt an External 

Gearbox Removal From the ESV 

Definition 

RR requested that we clarify that the 

separation of a pair of major mating 

engine module flanges in paragraph (g) 

of this AD does not include the 

separation of an engine external gearbox 

from the engine, which would not 

constitute a refurbishment shop visit. 

We agree. We changed paragraph (g) 

of this AD to state: ‘‘For the purpose of 

this AD, ESV is whenever engine 

maintenance performed prior to 

reinstallation requires the separation of 

a pair of major mating engine module 

flanges. Separation of flanges solely for 

the purpose of shipment without 

subsequent internal maintenance is not 

an ESV. Separation of the external 

gearbox engine mating flanges or 

removal of the external gearbox is also 

not classified as a shop visit.’’ 

Request To Delay Implementation of 

Reduced Rotating Parts Life Limits 

American Air Lines (AAL) and RR 

asked that we revise or remove 

paragraph (e)(2) of this AD to eliminate 

the requirement to assign the reduced 

maximum approved lives within 30 

days of the effective date of this AD and 

allow the current lives as published in 


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