[4910-13-P] D E PARTM EN T OF TRA
N SPORT

A TIO N F e d e ral Aviation

A dministration 14 CF R Part 39 [Docket No. FAA-2011-0961; Directorate Identifier 2011- NE -22-AD; Amendment 39-18090

; AD 2015-02-22] RIN 2120-AA64 Airworthin

ess Directives

; Rolls-Ro

y c e Corpor

a ti o n T urboprop and Turboshaft E n g ine
s AGENC
Y: Federal Aviat

i on Administration (FAA), DOT. ACT IO N
: Final rule. SU MM A RY: We are supe

r seding airworth

i ness directive (AD) 2012-

1 4-06 for certain Rolls-Royce Corporation

( RR C) 250-C20, -C20B, and -C20R/2 turboshaft engines. AD 2012-14-06 required

a one-time visual inspection and fluorescent-penetrant inspection (FPI) on certain 3rd-stage and 4!h-stage turbine wheels for
c r acks in the turbine blades. This new AD rep

l aces the one

- time visual inspection and FPI with repetitive visual inspections
and FP

i s . Th

i s AD

a l so adds certain engine models

to the appl

i cability. This AD was prompted

by the determination

that the one-time inspections required
by A D 2012-14-06 should be changed

to repetitive inspections.
We are issuing this AD to prevent failure of3rd_stage
and 4rn-stage turbine wheel

b l ades, which could cause engine failure and damage

to the aircraft. DATES: This AD is effective (INSERT DATE 35 DAYS AFTER DATE OF P U BLICATION

IN THE FEDERAL REGISTER]. ADDRESSES:

For service information identified

in thi
s AD

, contact Rolls-Royce Corporation

, 450 South Meridian Street

, Indianapolis

, IN 46225-1103

; phone: 888-255- 4766 or 317-230-2720; email: helicoptercustsupp

@ rolls-royce.com; Internet: www.rolls-royce. com. You may view this service information

at the FAA, Engine



### & Propeller Directorate

, 12 New England Executive Park

, Burlington

, MA. For information

on the availability ofthis material

at the FAA, call781-238-7125. Exa mi n in g t h e A D D oc k e t You may examine the AD docket on the Internet

at http: //www. regulations.gov

by searching
for and locating Docket No.
F AA-20 11-0961;

or in pe r son at the Docket Management Facility between

9 a.m. and
5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received

, and other information.
The address for the Docket Office (phone: 800-647-5527)

is Document Management Facility, U.S. Department ofTransportation, Do
c ket Operations, M-30

, West Building Ground Floor, Room W 12-140

, 1200 New Jersey Avenue SE., Washington

, DC 20590. F O R FU R T H E R I NF ORMATIO N C O NTACT

: John Tallarovic, Aerospace Engineer, Chicago Aircraft Certification Office

, FAA, 2300 E. Devon Ave.

, Des Plaines,
IL 600 18

; phone

: 847-294-8180;

fax: 847-294-7834; email: john.m.tallarovic

@ faa.gov. SU P PLE M E NT A RY

I N FORM AT IO N: Di s cu ss
i o n We issued

a notice of proposed rulemaking (NPRM)

to amend
14 CFR part 39 to s uper se de AD 2012-14-06, Amendment 39-17120

(7 7 FR 40479, July 10

, 2012), ("AD 20 12-14-06").

A D 2012-14-06 applied

to certain RRC 250-C20,

- C20B, and -C20R/

2 turboshaft eng in es. The N PRM published

in the Fed
e r a l Register
on Oct ober 2, 2014 (79 FR 59463). The N PRM was prompted

by determination

t h at the one-time inspections required

b y AD 2012-14

- 06 should
be changed

to repetitive inspect

i ons. The NPRM propo sed to replace the one-time visual inspection
and FPI with repetitive visual in spec tion

s and FP

i s, and also to require

a visual inspection

a nd FPI after any engine hot s tart

. The NPRM also proposed

to add certain engine model

s to the applicabi lity

. We are 2issuing this AD to prevent failure of3rd_stage
and 4th-stage turbine wheel blades, which could cause engine failure and damage

to the aircraft. Co mment

s We gave the public the opportunity

to participate

in developing
this AD. The following presents the comments received
on the NPRM (79 FR 59463, October

2, 2014) and the FAA's response

to each comment. R eq u est to Remove

a Certain Propo

s ed In s pection Requirement RRC requested that we remove the requirement

to in spect the 3rd-stage and 4th_ stage turbine wheels after

a hot start because they are already prohibited from further use after

a hot start by the maintenance instructions. We agree. Maintenance instructions clearly direct replacement

of 3rd -stage and 4th-stage turbine wheels following

a hot start. We removed from this AD the requirement to perform

a visual inspection
and an FPI on the affected turbine wheels after any hot start. Requ es t to Limit Applicability RRC requested that we restrict applicability

of the AD to only those affected engines

th at are installed
on MD helicopters because the majority
of failures have occurred
on MD helicopters. We disagree. Failures have occurred

in installations

on other than MD helicopters. Also, the FAA cannot ensure that parts once used on MD helicopters have not been subsequently installed
on other engines
or he li copter models. We did not change this AD. Request

to Delete

a Certain Reference RRC requested that we remove, from the Actions Since AD 2012-14 -06 Was Published paragraph, reference

to 3rd-stage turbine wheel failures
by replacing
the words ''3rd_stage and" with the words '·two additional'' because additiona

l failures only occurred in 4th-stage turbine wheels.



### 3We agree. The new failures since
A D 20 12-14-06 was published were in 4 th - stage turbine whee

l s . However

, the paragraph

, Actions Since AD 2012-14-06 was Published

, wh ich appeared

in the N PRM (October

2, 2014 79 FR 59463), does not appear

in this final rule. We did not change this A D. 

### Reque
st to Revise

a Certain Paragraph RRC requested that

we add th e word

" potential

" before the word

" failures"

in the Actions Since AD 20 12-14-06 Was Publi

s hed paragraph. We agree. However,
the paragraph

, Action

s Since AD 2012-14-06 Was Publi

s hed

, which appeared

in the NPRM (October

2, 2014 79 FR 59463), does not appear in this final rule. We did not change this AD. 

### Request

to Revise the Costs of Complia

nc e RR C requested that we change,

in the Costs of Compliance paragraph

, the estimated time to conduct the inspection from one hour to two hour
s. We ag ree

. We changed our estimate

in thi
s AD to
r e flect two hours of labor to co nduct the inspection. 

### Request

to Revise the Labor Rate RRC requested that

we change

, in the Costs of Compliance paragraph,
the labor rat e from $85 per hour to $116 per hour. We disagree. The rate of $85
p e r hour

i s provided

by th e FAA Office of Aviation Policy and Plan

s for us to use when estimating
the labor costs of complying with AD requirements.

We did not change this AD. 

### Request

to Revise the Costs of Compliance RRC requested that

we add the word ··initial" before the stated cost in the Costs of Compliance paragraph. We partially agree. We did not insert the word "initial'

· , but we clarified that our estimate
of costs of compliance

are for one inspection

, whether initial or recurring. 4

### Reque

s t to Revise

a Definition RRC requested that we change our definition

of a hot start. We partiall

y agree. We agree with the suggested changes because they clarify the definition

of a hot start. However

, in our reply to a prior comment,
we agreed

to remove th e inspection requirements associated with

a hot start. Therefore,
we have deleted
all requirements

in this AD to conduct inspections
afte

r hot starts, and have deleted the Definition paragraph. 

### Con clu

s ion We reviewed the relevant data, considered

the comments received, and determined that air safety and the public intere
st require adopting this AD with the changes described previously.
We have determined
that these minor changes: • Are consistent with the intent that was proposed

in the N PRM (79 

### FR 59463, October

2, 2014) for correcting
the un safe condition; and • Do not add any additional burden
up on the public than was already proposed in the NPRM (79 

### FR 59463

, October

2, 20 14). We also determined that these changes will not significantly increase the economic burden on any ope rator or increase the scope of this AD. 

### Costs of Co mpliance We estimate that this AD affects 3,769 engines

in sta lled on aircraft
of U.S. registry. We also estimate that it will take about

2 hours per engine

to comply with the inspection requirement

of this AD. The average labor rate is $85 per hour. Based on these figures

, we estimate the cost of this AD on U.S. operators
for one inspection

to be $640,730. 

### Aut
h ority 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. 5SubtitleVII,AviationPrograms,describesinmoredetailthescopeoftheAgency'sauthority.WeareissuingthisrulemakingundertheauthoritydescribedinSubtitleVII,PartA,SubpartIII,Section44701,"Generalrequirements."Underthatsection,CongresschargestheFAAwithpromotingsafeflightofcivilaircraftinaircommercebyprescribingregulationsforpractices,methods,andprocedurestheAdministratorfindsnecessaryforsafetyinaircommerce.Thisregulationiswithinthescopeofthatauthoritybecauseitaddressesanunsafeconditionthatislikelytoexistordeveloponproductsidentifiedinthisrulemakingaction.RegulatoryFindingsWehavedeterminedthatthisADwillnothavefederalismimplicationsunderExecutiveOrder13132.ThisADwillnothaveasubstantialdirecteffectontheStates,ontherelationshipbetweenthenationalgovernmentandtheStates,oronthedistributionofpowerandresponsibilitiesamongthevariouslevelsofgovernment.Forthereasonsdiscussedabove,IcertifythatthisAD:(1)Isnota"significantregulatoryaction"underExecutiveOrder12866,(2)Isnota"significantrule"underDOTRegulatoryPoliciesandProcedures(44FR11034,February26,1979),(3)WillnotaffectintrastateaviationinAlaska,and(4)Willnothaveasignificanteconomicimpact,positiveornegative,onasubstantialnumberofsmallentitiesunderthecriteriaoftheRegulatoryFlexibilityAct.ListofSubjectsin14CFRPart39Airtransportation,Aircraft,Aviationsafety,Incorporationbyreference,Safety.AdoptionoftheAmendmentAccordingly,undertheauthoritydelegatedtomebytheAdministrator,theFAAamends14CFRpart39asfollows:6PART39-AIRWORTHINESSDIRECTIVES1.Theauthoritycitationforpart39continuestoreadasfollows:Authority:49U.S.C.106(g),40113,44701.§39.13(Amended]2.TheFAAamends§39.13byremovingAirworthinessDirective(AD)2012-14-06,Amendment39-17120(77FR40479,July10,2012),andaddingthefollowingnewAD:2015-02-22Rolls-RoyceCorporation:Amendment39-18090;DocketNo.FAA-2011-0961;DirectorateIdentifier2011-NE-22-AD.(a)EffectiveDateThisADiseffective[INSERTDATE35DAYSAFTERDATEOFPUBLICATIONINTHEFEDERALREGISTER].(b)AffectedADsThisADsupersedesAD2012-14-06,Amendment39-17120(77FR40479,July10,2012).(c)ApplicabilityThisADappliestoRolls-RoyceCorporation(RRC)250-B17,-B17B,-Bl7C,-B17D,-B17E,-B17F,-B17Fil,-B17F/2turbopropengines;and250-C20,-C20B,-C20F,-C20J,-C20R,-C20R/1,-C20R/2,-C20R/4,-C20S,and-C20Wturboshaftengines;witheithera3rd-stageturbinewheel,partnumber(PIN)23065818,ora41h-stageturbinewheel,PIN23055944,installed.(d) UnsafeConditionThisADwaspromptedbyinvestigationsthatrevealedthatnotall3rd-stageand41h-stageturbinewheelbladefailureswereidentifiedbytheone-timeinspectionsrequiredbyAD2012-14-06,Amendment39-17120(77FR40479,July10,2012).Wedeterminedthattoaddresstheunsafecondition,repetitiveinspectionsarerequired,triggeredby7

# hours since

l ast inspection (HSLI). We are issuing

th is AD to prevent failure of 3rd

- stage and
4 th -sta ge turbin

e wheel blade

s, w hich could cause engine

fa ilur
e and damage

to the aircraft. (e) 

# Compliance 

# Comply with this A D wit hin the comp liance times specified, unless already done. Afte

r the effect

i ve date of this AD: (1) Within 1,750 HSLI

, remove

th e affected turbine wh ee
l s and perform

a visua

l inspection and

a fluorescent-penetrant inspection (FPI) on the removed turbi ne wheels for cracks

at the trailing edge of the turbine

b l ades near the fillet
at the rim. (2) Any time the power turbine

is disassemb

l ed, perform

a visual inspection
and an FPI on the affected turbine wheels for cracks

at the trailing edge of the turbine blades, n ea r the fillet at the rim

. (3) Th ereafte

r , re-inspect every



# I , 750 HSLI. (4) D o not

r eturn to service any turbine wheels that have cracks detected. (f) A ltern at
i ve Met
h ods of Compliance (AMOCs) 

# The Manage

r , Chicago Aircraft Certificat

i o n Office

, may approve AMOCs
for this AD. Use the procedures found
in 14 CF R 3 9. 19 to make yo ur request. (g) 

# Related Information (1) 

# For more information about thi
s AD, contact John Tallarovic

, Aerospace Engineer,
Ch

i cago Aircraft Certification Office, FAA, 2300 E. Devon Ave., De
s Plaines

, IL 60018; phone: 847-294-8180;

fax: 847-294-7834; email: john.m.tallarovic@faa.gov. (2) RRC Alert Commercial

E ngine Bulletin (CEB) No. CEB-A-1407, Revision

3, dated May 19 ,2014, and Alert CEB No. CEB-A-72-4098,

R evision

3, dated May 19

, 2014 (combined

int o one document), which are not incorporated

by reference

in this AD, can be obtained from RRC, using the contact information

in paragraph (g)(3) of this AD. 

# 8(3)ForserviceinformationidentifiedinthisAD,contactRolls-RoyceCorporationCustomerSupport,450SouthMeridianStreet,Indianapolis,IN46225-1103;phone:888-255-4766or317-230-2720;email:helicoptercustsupp@rolls-royce.com;Internet:www.rolls-royce.com.(4)YoumayviewthisserviceinformationattheFAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA01803.ForinformationontheavailabilityofthismaterialattheFAA,call781-238-7125.(h)MaterialIncorporatedbyReferenceNone.IssuedinBurlington,Massachusetts,onJanuary20,2015.ColleenM.D'Alessandro,AssistantDirectorateManager,Engine&PropellerDirectorate,AircraftCertificationService.9