Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines, 24791-24793 [2015-10075]
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Federal Register / Vol. 80, No. 84 / Friday, May 1, 2015 / Rules and Regulations
the airplane, in accordance with step 2) in
‘‘DESIRED ACTION’’ of Boeing Multi
Operator Message MOM–MOM–15–0248–
01B, dated April 19, 2015; or Boeing Multi
Operator Message MOM–MOM–15–0248–
01B(R1), dated April 20, 2015. The main and
auxiliary power unit (APU) batteries do not
need to be disconnected when performing
the electrical power deactivation. Repeat the
electrical power deactivation thereafter at
intervals not to exceed 120 days.
(1) Within 120 days after the last electrical
power deactivation in accordance with step
2) in ‘‘DESIRED ACTION’’ of Boeing Multi
Operator Message MOM–MOM–15–0248–
01B, dated April 19, 2015; or Boeing Multi
Operator Message MOM–MOM–15–0248–
01B(R1), dated April 20, 2015.
(2) Within 120 days after the date of
issuance of the original certificate of
airworthiness or the date of issuance of the
original export certificate of airworthiness.
(3) Within 7 days after the effective date of
this AD.
(h) Special Flight Permit
Special flight permits, as described in
Section 21.197 and Section 21.199 of the
Federal Aviation Regulations (14 CFR 21.197
and 21.199), are not allowed.
(i) Alternative Methods of Compliance
(AMOCs)
(1) The Manager, Seattle Aircraft
Certification Office (ACO), FAA, has the
authority to approve AMOCs for this AD, if
requested using the procedures found in 14
CFR 39.19. In accordance with 14 CFR 39.19,
send your request to your principal inspector
or local Flight Standards District Office, as
appropriate. If sending information directly
to the manager of the ACO, send it to the
attention of the person identified in
paragraph (j) of this AD. Information may be
emailed to: 9-ANM-Seattle-ACO-AMOCRequests@faa.gov.
(2) Before using any approved AMOC,
notify your appropriate principal inspector,
or lacking a principal inspector, the manager
of the local flight standards district office/
certificate holding district office.
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(j) Related Information
For more information about this AD,
contact Kelly McGuckin, Aerospace
Engineer, Systems and Equipment Branch,
ANM–130S, FAA, Seattle Aircraft
Certification Office (ACO), 1601 Lind Avenue
SW., Renton, WA 98057–3356; phone: 425–
917–6490; fax: 425–917–6590; email:
Kelly.McGuckin@faa.gov.
(k) 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 Multi Operator Message MOM–
MOM–15–0248–01B, dated April 19, 2015.
The date appears only on the first page of this
document.
(ii) Boeing Multi Operator Message MOM–
MOM–15–0248–01B(R1), dated April 20,
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15:47 Apr 30, 2015
Jkt 235001
2015. The date appears only on the first page
of this document.
(3) For service information identified in
this AD, contact Boeing Commercial
Airplanes, Attention: Data & Services
Management, P.O. Box 3707, MC 2H–65,
Seattle, WA 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 the FAA, Transport Airplane Directorate,
1601 Lind Avenue SW., Renton, WA. 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 https://
www.archives.gov/federal-register/cfr/ibrlocations.html.
Issued in Renton, Washington, on April 23,
2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2015–10066 Filed 4–30–15; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2013–0766; Directorate
Identifier 2013–NE–26–AD; Amendment 39–
18149; AD 2014–17–08R1]
RIN 2120–AA64
Airworthiness Directives; Pratt &
Whitney Canada Corp. Turboprop
Engines
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
We are revising airworthiness
directive (AD) 2014–17–08 for all Pratt
& Whitney Canada Corp. (P&WC) PT6A–
114 and PT6A–114A turboprop engines.
AD 2014–17–08 required initial and
repetitive borescope inspections (BSIs)
of compressor turbine (CT) blades, and
the removal from service of blades that
fail inspection. This new AD adds an
additional single crystal CT blade,
reduces the affected population, and
corrects the Credit for Previous Action
paragraph. This AD was prompted by
P&WC development of an additional
single crystal CT blade that corrects the
unsafe condition. We are issuing this
AD to prevent failure of CT blades,
which could result in damage to the
engine and damage to the airplane.
DATES: This AD is effective June 5, 2015.
The Director of the Federal Register
approved the incorporation by reference
SUMMARY:
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24791
of a certain other publications listed in
this AD as of October 8, 2014 (79 FR
52172, September 3, 2014).
ADDRESSES: For service information
identified in this AD, contact Pratt &
Whitney Canada Corp., 1000 MarieVictorin, Longueuil, Quebec, Canada,
J4G 1A1; phone: 800–268–8000; fax:
450–647–2888; Internet: www.pwc.ca.
You may view this service information
at the FAA, Engine & Propeller
Directorate, 12 New England Executive
Park, Burlington, MA. For information
on the availability of this material at the
FAA, call 781–238–7125. Certain
service information is also available on
the Internet at https://
www.regulations.gov by searching for
and locating Docket No. FAA–2013–
0766.
Examining the AD Docket
You may examine the AD docket on
the Internet at https://
www.regulations.gov by searching for
and locating Docket No. FAA–2013–
0766; 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 address for the
Docket Office (phone: 800–647–5527) is
Document Management Facility, U.S.
Department of Transportation, Docket
Operations, M–30, West Building
Ground Floor, Room W12–140, 1200
New Jersey Avenue SE., Washington,
DC 20590.
FOR FURTHER INFORMATION CONTACT:
Barbara Caufield, Aerospace Engineer,
Engine Certification Office, FAA, Engine
& Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01803;
phone: 781–238–7146; fax: 781–238–
7199; email: barbara.caufield@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed
rulemaking (NPRM) to amend 14 CFR
part 39 to revise AD 2014–17–08,
Amendment 39–17961 (79 FR 52172,
September 3, 2014), (‘‘AD 2014–17–
08’’). AD 2014–17–08 applied to all
P&WC PT6A–114 and PT6A–114A
turboprop engines. The NPRM
published in the Federal Register on
December 1, 2014 (79 FR 71031). The
NPRM was prompted by P&WC
development of an additional single
crystal CT blade that corrects the unsafe
condition. The addition of this new part
number (P/N) reduces the affected
population. The NPRM proposed to
retain all the requirements of AD 2014–
17–08. The NPRM also proposed to add
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Federal Register / Vol. 80, No. 84 / Friday, May 1, 2015 / Rules and Regulations
alone only references one of the three
blades listed as terminating action in
paragraph (e)(2) of this AD.
We agree. We added references to the
two additional SBs in paragraph (h)(2)
of this AD.
the additional single crystal CT blade
that corrects the unsafe condition,
reduce the affected population, and
correct the Credit for Previous Action
paragraph. We are issuing this AD to
prevent failure of CT blades, which
could result in damage to the engine
and damage to the airplane.
Comments
We gave the public the opportunity to
participate in developing this AD. The
following presents the comments
received on the NPRM (79 FR 71031,
December 1, 2014) and the FAA’s
response to each comment.
Request To Clarify Disposition of
Removed CT Blades
Hawkins Aero Engineering, Inc. and
another commenter requested that we
state more clearly whether pre-SB
(service bulletin) PT6A–72–1669 CT
blades removed as a result of this AD
can be reinstalled in the same engine,
the same model engine, or a different
model engine.
We disagree. Paragraph (e)(1)(iii)(B) of
this AD clearly states that to re-install
removed pre-SB PT6A–72–1669 CT
blades, the blades must pass a two-blade
metallurgical inspection to determine
airworthiness in accordance with
paragraph 3.B., Accomplishment
Instructions, of P&WC Service Bulletin
(SB) No. PT6A–72–1669, Revision 9,
dated June 28, 2013. We did not change
this AD.
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Request To Not Mandate Installation of
Single Crystal CT Blades
One commenter requested that we not
mandate the installation of single crystal
CT blades because two of the P/Ns cited
as replacement blades have experienced
low-time failures, indicating a design or
manufacturing flaw.
We disagree. While there have been
some failures of single crystal CT blades
on a different engine model, that failure
mode is well understood and does not
affect the engines that are the subject of
this AD. For the engines that are subject
to this AD, single crystal blades provide
a significant improvement in durability
and a significant reduction in CT blade
failures overall. We did not change this
AD.
Request To Reference Two Additional
SBs
One commenter requested that we
reference P&WC SBs No. PT6A–72–1727
and No. PT6A–72–1749 in addition to
P&WC SB No. PT6A–72–1669 because
each one of these SBs references one of
the three single crystal CT blades that
can be installed as terminating action to
this AD. P&WC SB No. PT6A–72–1669
VerDate Sep<11>2014
15:47 Apr 30, 2015
Jkt 235001
Request To Include Alternative Method
of Compliance (AMOC) for Inspections
Hawkins Aero Engineering, Inc.
requested that we include in the AD an
AMOC to allow a visual inspection,
accomplished by splitting the engine at
the C-flange, as an alternative method to
the required periodic borescope
inspection of pre-SB PT6A–72–1669 CT
blades. The commenter states that this
suggested visual method would provide
easier detection of cracks.
We disagree. This AD contains the
required method for resolving the
unsafe condition. If an operator can
accomplish required actions in a better
way, or a way that better suits the
operator’s business processes, and the
alternative method provides an
acceptable level of safety, then the
operator can apply for an AMOC to use
that method to address the unsafe
condition in accordance with paragraph
(g)(2) of this AD. We did not change this
AD.
Request That We Address Failures in
Additional Blades
Hawkins Aero Engineering, Inc.
requested that we address single crystal
CT blade failures either in this or in
another AD because there have been
several low-time single crystal CT blade
failures in several different PT6 engine
models, some of which are single engine
installations.
We disagree. Low-time failures that
occurred on engine models not affected
by this AD are due to a failure mode that
is well understood. That failure mode
does not occur in the engine models that
are the subject of this AD. We did not
change this AD.
Conclusion
We reviewed the relevant data,
considered the comments received, and
determined that air safety and the
public interest 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 NPRM (79 FR
71031, December 1, 2014) for correcting
the unsafe condition; and
• Do not add any additional burden
upon the public than was already
proposed in NPRM (79 FR 71031,
December 1, 2014).
We also determined that these
changes will not increase the economic
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burden on any operator or increase the
scope of this AD.
Costs of Compliance
We estimate that this AD affects 300
engines installed on airplanes of U.S.
registry. We also estimate that it would
take about 4 hours per engine to perform
the required inspection and 8 hours to
replace the blades. The average labor
rate is $85 per hour. Required parts cost
about $59,334 per engine. Based on
these figures, we estimate the cost of
this AD on U.S. operators to be
$18,106,200.
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 have 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),
(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.
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Federal Register / Vol. 80, No. 84 / Friday, May 1, 2015 / Rules and Regulations
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 Airworthiness Directive (AD)
2014–17–08, Amendment 39–17961 (79
FR 52172, September 3, 2014), and
adding the following new AD:
■
2014–17–08R1 Pratt & Whitney Canada
Corp.: Amendment 39–18149; Docket
No. FAA–2013–0766; Directorate
Identifier 2013–NE–26–AD.
(a) Effective Date
This AD is effective June 5, 2015.
(b) Affected ADs
This AD replaces AD 2014–17–08,
Amendment 39–17961 (79 FR 52172,
September 3, 2014).
(c) Applicability
This AD applies to all Pratt & Whitney
Canada Corp. (P&WC) PT6A–114 and PT6A–
114A turboprop engines.
mstockstill on DSK4VPTVN1PROD with RULES
(d) Unsafe Condition
This AD was prompted by several
incidents of compressor turbine (CT) blade
failure, causing power loss, and engine
failure. We are issuing this AD to prevent
failure of CT blades, which could lead to
damage to the engine and damage to the
airplane.
(e) Compliance
Comply with this AD within the
compliance times specified, unless already
done.
(1) For engines installed with CT blades
other than P&WC single crystal CT blades,
part numbers (P/Ns) 3072791–01, 3072791–
02, or 3079351–01, do the following:
(i) Until removed, per the requirements of
this AD, borescope inspect the CT blade
leading and trailing edges, within the
following intervals, whichever occurs later:
(A) 150 operating hours after October 8,
2014; or
(B) 500 operating hours since new; or
(C) 500 operating hours since last
borescope inspection (BSI) of the CT blades;
or
(D) Before next flight after the effective
date of this AD.
(ii) Thereafter, repeat the inspection
required by paragraph (e)(1)(i) of this AD
VerDate Sep<11>2014
15:47 Apr 30, 2015
Jkt 235001
24793
every 500 flight hours time since last
inspection.
(iii) At the next hot section inspection
(HSI) after the effective date of this AD, and
each HSI thereafter, replace the complete set
of CT blades with any of the following:
(A) New CT blades;
(B) CT blades that have passed a two-blade
metallurgical inspection. Use paragraph 3.B.,
Accomplishment Instructions, of P&WC
Service Bulletin (SB) No. PT6A–72–1669,
Revision 9, dated June 28, 2013, to do the
inspection; or
(C) P&WC single crystal CT blades, P/N
3072791–01, 3072791–02, or 3079351–01.
(2) Replacement of the complete set of CT
blades with single crystal CT blades, P/N
3072791–01, 3072791–02, or 3079351–01 is
terminating action for the requirements of
paragraph (e)(1) of this AD.
(3) By October 8, 2017, replace the
complete set of CT blades with P&WC single
crystal CT blades, P/N 3072791–01,
3072791–02, or 3079351–01.
(3) The following service information was
approved for IBR on October 8, 2014 (79 FR
52172, September 3, 2014).
(i) Pratt & Whitney Canada Service Bulletin
No. PT6A–72–1669, Revision 9, dated June
28, 2013.
(ii) Reserved.
(4) For P&WC service information
identified in this AD, contact Pratt & Whitney
Canada Corp., 1000 Marie-Victorin,
Longueuil, Quebec, Canada, J4G 1A1; phone:
800–268–8000; fax: 450–647–2888; Internet:
www.pwc.ca.
(5) 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.
(6) 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: https://
www.archives.gov/federal-register/cfr/ibrlocations.html.
(f) Credit for Previous Action
Issued in Burlington, Massachusetts, on
April 17, 2015.
Thomas A. Boudreau,
Acting Directorate Manager, Engine &
Propeller Directorate, Aircraft Certification
Service.
Performance of the metallurgical
examination specified in paragraph
(e)(1)(iii)(B) of this AD on CT blades other
than P&WC single crystal CT blades, P/N
3072791–01, 3072791–02, or 3079351–01,
before the effective date of this AD fulfills the
initial inspection requirements of paragraph
(e)(1)(i) of this AD. However, you must still
comply with the repetitive BSI requirement
of paragraph (e)(1)(ii) of this AD until you
complete the mandatory terminating action
of paragraph (e)(3) of this AD.
(g) Alternative Methods of Compliance
(AMOCs)
(1) AMOCs previously approved for AD
2014–17–08, Amendment 39–17961 (79 FR
52172, September 3, 2014) are approved for
this AD.
(2) The Manager, Engine Certification
Office, FAA, may approve AMOCs for this
AD. Use the procedures found in 14 CFR
39.19 to make your request. You may email
your request to: ANE-AD-AMOC@faa.gov.
(h) Related Information
(1) For more information about this AD,
contact Barbara Caufield, Aerospace
Engineer, Engine Certification Office, FAA,
Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA
01803; phone: 781–238–7146; fax: 781–238–
7199; email: barbara.caufield@faa.gov.
(2) P&WC SB No. PT6A–72–1727, dated
August 23, 2013, and SB No. PT6A–72–1749,
dated September 23, 2014, which are not
incorporated by reference in this AD, can be
obtained from P&WC using the contact
information in paragraph (i)(4) of this AD.
(i) 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.
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[FR Doc. 2015–10075 Filed 4–30–15; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 71
[Docket No. FAA–2015–0794; Airspace
Docket No. 15–ASO–5]
Proposed Amendment of Class E
Airspace; Jupiter, FL
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule; technical
amendment.
AGENCY:
This action amends Class D
Airspace at Jupiter, FL, by removing
reference to Restricted Area R–2936 in
the regulatory text of the Class D
airspace area as the restricted area is no
longer needed. This action also updates
the geographic coordinates of the
airport.
DATES: Effective 0901 UTC, June 25,
2015. The Director of the Federal
Register approves this incorporation by
reference action under title 1, Code of
Federal Regulations, part 51, subject to
the annual revision of FAA Order
7400.9 and publication of conforming
amendments.
ADDRESSES: FAA Order 7400.9Y,
Airspace Designations and Reporting
Points, and subsequent amendments can
be viewed online at https://www.faa.gov/
SUMMARY:
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]]>Agencies
[Federal Register Volume 80, Number 84 (Friday, May 1, 2015)]
[Rules and Regulations]
[Pages 24791-24793]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-10075]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2013-0766; Directorate Identifier 2013-NE-26-AD;
Amendment 39-18149; AD 2014-17-08R1]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop
Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are revising airworthiness directive (AD) 2014-17-08 for
all Pratt & Whitney Canada Corp. (P&WC) PT6A-114 and PT6A-114A
turboprop engines. AD 2014-17-08 required initial and repetitive
borescope inspections (BSIs) of compressor turbine (CT) blades, and the
removal from service of blades that fail inspection. This new AD adds
an additional single crystal CT blade, reduces the affected population,
and corrects the Credit for Previous Action paragraph. This AD was
prompted by P&WC development of an additional single crystal CT blade
that corrects the unsafe condition. We are issuing this AD to prevent
failure of CT blades, which could result in damage to the engine and
damage to the airplane.
DATES: This AD is effective June 5, 2015.
The Director of the Federal Register approved the incorporation by
reference of a certain other publications listed in this AD as of
October 8, 2014 (79 FR 52172, September 3, 2014).
ADDRESSES: For service information identified in this AD, contact Pratt
& Whitney Canada Corp., 1000 Marie-Victorin, Longueuil, Quebec, Canada,
J4G 1A1; phone: 800-268-8000; fax: 450-647-2888; Internet: www.pwc.ca.
You may view this service information at the FAA, Engine & Propeller
Directorate, 12 New England Executive Park, Burlington, MA. For
information on the availability of this material at the FAA, call 781-
238-7125. Certain service information is also available on the Internet
at https://www.regulations.gov by searching for and locating Docket No.
FAA-2013-0766.
Examining the AD Docket
You may examine the AD docket on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2013-
0766; 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 address for the Docket Office (phone: 800-647-
5527) is Document Management Facility, U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aerospace Engineer,
Engine Certification Office, FAA, Engine & Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; phone: 781-238-7146;
fax: 781-238-7199; email: barbara.caufield@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to revise AD 2014-17-08, Amendment 39-17961 (79 FR 52172,
September 3, 2014), (``AD 2014-17-08''). AD 2014-17-08 applied to all
P&WC PT6A-114 and PT6A-114A turboprop engines. The NPRM published in
the Federal Register on December 1, 2014 (79 FR 71031). The NPRM was
prompted by P&WC development of an additional single crystal CT blade
that corrects the unsafe condition. The addition of this new part
number (P/N) reduces the affected population. The NPRM proposed to
retain all the requirements of AD 2014-17-08. The NPRM also proposed to
add
[[Page 24792]]
the additional single crystal CT blade that corrects the unsafe
condition, reduce the affected population, and correct the Credit for
Previous Action paragraph. We are issuing this AD to prevent failure of
CT blades, which could result in damage to the engine and damage to the
airplane.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the NPRM (79
FR 71031, December 1, 2014) and the FAA's response to each comment.
Request To Clarify Disposition of Removed CT Blades
Hawkins Aero Engineering, Inc. and another commenter requested that
we state more clearly whether pre-SB (service bulletin) PT6A-72-1669 CT
blades removed as a result of this AD can be reinstalled in the same
engine, the same model engine, or a different model engine.
We disagree. Paragraph (e)(1)(iii)(B) of this AD clearly states
that to re-install removed pre-SB PT6A-72-1669 CT blades, the blades
must pass a two-blade metallurgical inspection to determine
airworthiness in accordance with paragraph 3.B., Accomplishment
Instructions, of P&WC Service Bulletin (SB) No. PT6A-72-1669, Revision
9, dated June 28, 2013. We did not change this AD.
Request To Not Mandate Installation of Single Crystal CT Blades
One commenter requested that we not mandate the installation of
single crystal CT blades because two of the P/Ns cited as replacement
blades have experienced low-time failures, indicating a design or
manufacturing flaw.
We disagree. While there have been some failures of single crystal
CT blades on a different engine model, that failure mode is well
understood and does not affect the engines that are the subject of this
AD. For the engines that are subject to this AD, single crystal blades
provide a significant improvement in durability and a significant
reduction in CT blade failures overall. We did not change this AD.
Request To Reference Two Additional SBs
One commenter requested that we reference P&WC SBs No. PT6A-72-1727
and No. PT6A-72-1749 in addition to P&WC SB No. PT6A-72-1669 because
each one of these SBs references one of the three single crystal CT
blades that can be installed as terminating action to this AD. P&WC SB
No. PT6A-72-1669 alone only references one of the three blades listed
as terminating action in paragraph (e)(2) of this AD.
We agree. We added references to the two additional SBs in
paragraph (h)(2) of this AD.
Request To Include Alternative Method of Compliance (AMOC) for
Inspections
Hawkins Aero Engineering, Inc. requested that we include in the AD
an AMOC to allow a visual inspection, accomplished by splitting the
engine at the C-flange, as an alternative method to the required
periodic borescope inspection of pre-SB PT6A-72-1669 CT blades. The
commenter states that this suggested visual method would provide easier
detection of cracks.
We disagree. This AD contains the required method for resolving the
unsafe condition. If an operator can accomplish required actions in a
better way, or a way that better suits the operator's business
processes, and the alternative method provides an acceptable level of
safety, then the operator can apply for an AMOC to use that method to
address the unsafe condition in accordance with paragraph (g)(2) of
this AD. We did not change this AD.
Request That We Address Failures in Additional Blades
Hawkins Aero Engineering, Inc. requested that we address single
crystal CT blade failures either in this or in another AD because there
have been several low-time single crystal CT blade failures in several
different PT6 engine models, some of which are single engine
installations.
We disagree. Low-time failures that occurred on engine models not
affected by this AD are due to a failure mode that is well understood.
That failure mode does not occur in the engine models that are the
subject of this AD. We did not change this AD.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest 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
NPRM (79 FR 71031, December 1, 2014) for correcting the unsafe
condition; and
Do not add any additional burden upon the public than was
already proposed in NPRM (79 FR 71031, December 1, 2014).
We also 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 affects 300 engines installed on airplanes
of U.S. registry. We also estimate that it would take about 4 hours per
engine to perform the required inspection and 8 hours to replace the
blades. The average labor rate is $85 per hour. Required parts cost
about $59,334 per engine. Based on these figures, we estimate the cost
of this AD on U.S. operators to be $18,106,200.
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 have 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),
(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.
[[Page 24793]]
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
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD)
2014-17-08, Amendment 39-17961 (79 FR 52172, September 3, 2014), and
adding the following new AD:
2014-17-08R1 Pratt & Whitney Canada Corp.: Amendment 39-18149;
Docket No. FAA-2013-0766; Directorate Identifier 2013-NE-26-AD.
(a) Effective Date
This AD is effective June 5, 2015.
(b) Affected ADs
This AD replaces AD 2014-17-08, Amendment 39-17961 (79 FR 52172,
September 3, 2014).
(c) Applicability
This AD applies to all Pratt & Whitney Canada Corp. (P&WC) PT6A-
114 and PT6A-114A turboprop engines.
(d) Unsafe Condition
This AD was prompted by several incidents of compressor turbine
(CT) blade failure, causing power loss, and engine failure. We are
issuing this AD to prevent failure of CT blades, which could lead to
damage to the engine and damage to the airplane.
(e) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(1) For engines installed with CT blades other than P&WC single
crystal CT blades, part numbers (P/Ns) 3072791-01, 3072791-02, or
3079351-01, do the following:
(i) Until removed, per the requirements of this AD, borescope
inspect the CT blade leading and trailing edges, within the
following intervals, whichever occurs later:
(A) 150 operating hours after October 8, 2014; or
(B) 500 operating hours since new; or
(C) 500 operating hours since last borescope inspection (BSI) of
the CT blades; or
(D) Before next flight after the effective date of this AD.
(ii) Thereafter, repeat the inspection required by paragraph
(e)(1)(i) of this AD every 500 flight hours time since last
inspection.
(iii) At the next hot section inspection (HSI) after the
effective date of this AD, and each HSI thereafter, replace the
complete set of CT blades with any of the following:
(A) New CT blades;
(B) CT blades that have passed a two-blade metallurgical
inspection. Use paragraph 3.B., Accomplishment Instructions, of P&WC
Service Bulletin (SB) No. PT6A-72-1669, Revision 9, dated June 28,
2013, to do the inspection; or
(C) P&WC single crystal CT blades, P/N 3072791-01, 3072791-02,
or 3079351-01.
(2) Replacement of the complete set of CT blades with single
crystal CT blades, P/N 3072791-01, 3072791-02, or 3079351-01 is
terminating action for the requirements of paragraph (e)(1) of this
AD.
(3) By October 8, 2017, replace the complete set of CT blades
with P&WC single crystal CT blades, P/N 3072791-01, 3072791-02, or
3079351-01.
(f) Credit for Previous Action
Performance of the metallurgical examination specified in
paragraph (e)(1)(iii)(B) of this AD on CT blades other than P&WC
single crystal CT blades, P/N 3072791-01, 3072791-02, or 3079351-01,
before the effective date of this AD fulfills the initial inspection
requirements of paragraph (e)(1)(i) of this AD. However, you must
still comply with the repetitive BSI requirement of paragraph
(e)(1)(ii) of this AD until you complete the mandatory terminating
action of paragraph (e)(3) of this AD.
(g) Alternative Methods of Compliance (AMOCs)
(1) AMOCs previously approved for AD 2014-17-08, Amendment 39-
17961 (79 FR 52172, September 3, 2014) are approved for this AD.
(2) The Manager, Engine Certification Office, FAA, may approve
AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make
your request. You may email your request to: ANE-AD-AMOC@faa.gov.
(h) Related Information
(1) For more information about this AD, contact Barbara
Caufield, Aerospace Engineer, Engine Certification Office, FAA,
Engine & Propeller Directorate, 12 New England Executive Park,
Burlington, MA 01803; phone: 781-238-7146; fax: 781-238-7199; email:
barbara.caufield@faa.gov.
(2) P&WC SB No. PT6A-72-1727, dated August 23, 2013, and SB No.
PT6A-72-1749, dated September 23, 2014, which are not incorporated
by reference in this AD, can be obtained from P&WC using the contact
information in paragraph (i)(4) of this AD.
(i) 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.
(3) The following service information was approved for IBR on
October 8, 2014 (79 FR 52172, September 3, 2014).
(i) Pratt & Whitney Canada Service Bulletin No. PT6A-72-1669,
Revision 9, dated June 28, 2013.
(ii) Reserved.
(4) For P&WC service information identified in this AD, contact
Pratt & Whitney Canada Corp., 1000 Marie-Victorin, Longueuil,
Quebec, Canada, J4G 1A1; phone: 800-268-8000; fax: 450-647-2888;
Internet: www.pwc.ca.
(5) 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.
(6) 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:
https://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued in Burlington, Massachusetts, on April 17, 2015.
Thomas A. Boudreau,
Acting Directorate Manager, Engine & Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2015-10075 Filed 4-30-15; 8:45 am]
BILLING CODE 4910-13-P
