Special Conditions: Safran Aircraft Engines, Silvercrest-2 SC-2D; Rated Takeoff Thrust at High Ambient Temperature, 30800-30802 [2017-14043]
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30800
Federal Register / Vol. 82, No. 126 / Monday, July 3, 2017 / Proposed Rules
sideslip considered appropriate for the
airplane must not result in
uncontrollable flight characteristics.
Issued in Kansas City, Missouri, on June
26, 2017.
Pat Mullen,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2017–13991 Filed 6–30–17; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 33
[Docket No. FAA–2017–0586; Notice No. 33–
17–01–SC]
Special Conditions: Safran Aircraft
Engines, Silvercrest-2 SC–2D; Rated
Takeoff Thrust at High Ambient
Temperature
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
AGENCY:
This action proposes special
conditions for the Safran Aircraft
Engines (SAE), Silvercrest-2 SC–2D
engine model. This engine will have a
novel or unusual design feature
associated with an additional takeoff
rating that increases the exhaust gas
temperature (EGT) limit to maintain
takeoff thrust in certain high ambient
temperature conditions for a maximum
accumulated usage of 20 minutes in any
one flight. The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for this
design feature. These proposed special
conditions contain the additional safety
standards that the Administrator
considers necessary to establish a level
of safety equivalent to that established
by the existing airworthiness standards.
DATES: Send your comments on or
before July 6, 2017.
ADDRESSES: Send comments identified
by docket number [FAA–2017–0586]
using any of the following methods:
• Federal eRegulations Portal: Go to
https://www.regulations.gov and follow
the online instructions for sending your
comments electronically.
• Mail: Send comments to Docket
Operations, M–30, U.S. Department of
Transportation (DOT), 1200 New Jersey
Avenue SE., Room W12–140, West
Building Ground Floor, Washington,
DC, 20590–0001.
• Hand Delivery of Courier: Take
comments to Docket Operations in
Room W12–140 of the West Building
sradovich on DSK3GMQ082PROD with PROPOSALS
SUMMARY:
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Ground Floor at 1200 New Jersey
Avenue SE., Washington, DC, between 8
a.m., and 5 p.m., Monday through
Friday, except Federal holidays.
• Fax: Fax comments to Docket
Operations at 202–493–2251.
Privacy: In accordance with 5 U.S.C.
553(c), DOT solicits comments from the
public to better inform its rulemaking
process. DOT posts these comments
without edit, including any personal
information the commenter provides, to
https://www.regulations.gov, as
described in the system of records
notice (DOT/ALL–14 FDMS), which can
be reviewed at https://
www.transportation.gov/privacy.
Docket: Background documents or
comments received may be read at
https://www.regulations.gov at any time.
Follow the online instructions for
accessing the docket or go to the Docket
Operations Room in W12–140 of the
West Building Ground Floor at 1200
New Jersey Avenue SE., Washington,
DC, between 9 a.m., and 5 p.m., Monday
through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Tara
Fitzgerald, ANE–112, Engine and
Propeller Directorate, Aircraft
Certification Service, 1200 District
Avenue, Burlington, Massachusetts,
01803–5213; telephone (781) 238–7130;
facsimile (781) 238–7199; email
Tara.Fitzgerald@faa.gov.
SUPPLEMENTARY INFORMATION:
Comments Invited
Certification of the Silvercrest-2 SC–
2D engine model is currently scheduled
for August 2018. The substance of these
special conditions has been subject to
the notice and public comment
procedure. Therefore, because a delay
would significantly affect the
applicant’s certification of the engine,
we are shortening the public comment
period to end on July 6, 2017.
We invite interested persons to
participate in this rulemaking by
submitting written comments, data, or
views. The agency also invites
comments relating to the economic,
environmental, energy, or federalism
impacts that might result from adopting
the proposals in this document. The
most helpful comments reference a
specific portion of the proposed special
conditions, explain the reason for any
recommended change, and include
supporting data. To ensure the docket
does not contain duplicate comments,
commenters should send only one copy
of written comments, or if comments are
filed electronically, commenters should
submit only one time.
We will file in the docket all
comments we receive, as well as a
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Sfmt 4702
report summarizing each substantive
public contact with FAA personnel
concerning this proposed rulemaking.
Before acting on this special condition,
we will consider all comments we
receive on or before the closing date for
comments. We will consider comments
filed after the comment period has
closed if it is possible to do so without
incurring expense or delay. We may
change these special conditions based
on the comments we receive.
Background
On April 19, 2011, SNECMA, now
known as SAE, applied for a type
certificate for the Silvercrest-2 SC–2D
engine model. On April 30, 2014, SAE
requested an extension to their original
type certificate application, which the
FAA granted through June 30, 2015. On
May 26, 2015, SAE requested another
extension to their type certificate
application, which the FAA granted
through September 30, 2018.
SAE proposed an additional takeoff
rating to maintain takeoff thrust in
certain high ambient temperature
conditions with all engines operating
(AEO) for the Silvercrest-2 SC–2D
engine model. Therefore, the
Silvercrest-2 SC–2D engine model
would have two different takeoff ratings.
The first rating corresponds with the
rated takeoff thrust of the engine. The
second takeoff rating maintains the
takeoff thrust in certain high ambient
temperature conditions. This additional
takeoff rating is named ‘‘Rated Takeoff
Thrust at High Ambient Temperature’’
(Rated TOTHAT). The Rated TOTHAT
is an approved engine thrust developed
under specified altitudes and
temperatures within the operating
limitations established for the engine
during takeoff operation for a maximum
usage of 20 minutes in any one flight.
Type Certification Basis
Under the provisions of title 14, Code
of Federal Regulations (14 CFR) 21.17,
SAE must show that the Silvercrest-2
SC–2D meets the applicable provisions
of 14 CFR part 33, as amended by
Amendments 33–1 through 33–34 in
effect on the date of application.
If the FAA finds that the applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for the Silvercrest-2 SC–2D engine
model, because of a novel or unusual
design feature, special conditions are
prescribed under the provisions of
§ 21.16.
Special conditions are initially
applicable to the model for which they
are issued. Should the type certificate
for that model be amended later to
include any other model that
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Federal Register / Vol. 82, No. 126 / Monday, July 3, 2017 / Proposed Rules
incorporates the same or similar novel
or unusual design feature, the special
conditions would also apply to the other
model under § 21.101.
In addition to complying with the
applicable product airworthiness
regulations and the requirements of the
special conditions, the Silvercrest-2 SC–
2D engine model must comply with the
fuel venting and exhaust emission
requirements of 14 CFR part 34.
The FAA issues special conditions, as
defined in 14 CFR 11.19, in accordance
with § 11.38, and they become part of
the type certification basis under
§ 21.17(a)(2).
sradovich on DSK3GMQ082PROD with PROPOSALS
Novel or Unusual Design Features
The Silvercrest-2 SC–2D engine
model will incorporate a novel or
unusual design feature, referred to as
‘‘Rated TOTHAT’’. This additional
takeoff rating increases the EGT limit to
maintain takeoff thrust in certain high
ambient temperature conditions for a
maximum of 20 minutes in any one
flight.
Discussion
The Rated TOTHAT is designed for
use during takeoff in specified high
altitudes and high ambient temperature
conditions to maintain thrust during
takeoff for a maximum of 20 minutes in
any one flight. These proposed special
conditions contain additional
mandatory post-flight inspection and
maintenance action requirements
associated with any use of the Rated
TOTHAT. These requirements add a
rating definition in part 1.1 and
mandate mandatory inspections in the
instructions for continued airworthiness
(ICA); instructions for installing and
operating the engine; engine rating and
operating limitations; instrument
connection; and endurance testing.
The current requirements of the
endurance test under § 33.87 represent a
typical airplane flight profile and the
severity of the takeoff rating. Therefore,
the endurance test under § 33.87 covers
normal, all-engines-operating takeoff
conditions for which the engine control
system limits the engine to the takeoff
thrust rating. It is intended to represent
the airplane flight profile during takeoff
under specified ambient temperatures
for a time until the mandatory
inspection and maintenance actions can
be performed.
These proposed special conditions
require additional test cycles that
include at least a 150 hours of engine
operation as specified in § 33.87(a), to
demonstrate the engine is capable of
performing the Rated TOTHAT rating
during AEO conditions without
disassembly or modification.
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The associated engine deterioration,
after use of the Rated TOTHAT, is not
known without the intervening
mandatory inspections in these special
conditions. These mandatory
inspections ensure the engine will
continue to comply with its certification
basis, which includes these proposed
special conditions, after any use of the
Rated TOTHAT. The applicant is
expected to assess the deterioration
from use of the Rated TOTHAT. The
airworthiness limitations section (ALS)
must prescribe the mandatory postflight inspections and maintenance
actions associated with any use of the
Rated TOTHAT.
These requirements maintain a level
of safety equivalent to the level
intended by the applicable
airworthiness standards in effect on the
date of application.
Applicability
As discussed above, these proposed
special conditions are applicable to the
Silvercrest-2 SC–2D engine model.
Should SAE apply at a later date for a
change to the type certificate to include
another model incorporating the same
novel or unusual design feature, the
special conditions would apply to that
model as well.
Conclusion
This action affects only the Rated
TOTHAT features on the Silvercrest-2
SC–2D engine model. It is not a rule of
general applicability and applies only to
SAE, who requested FAA approval of
this engine feature.
List of Subjects in 14 CFR Part 33
Aircraft, Engines, Aviation safety,
Reporting and recordkeeping
requirements.
The authority citation for these
special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, and 44704.
The Proposed Special Conditions
Accordingly, the FAA proposes, the
following special conditions as part of
the type certification basis for SAE,
Silvercrest-2 SC–2D engine model.
1. Part 1 Definition
‘‘Rated Take-off Thrust at High
Ambient Temperature’’ (Rated
TOTHAT) means the approved engine
thrust developed under specified
altitudes and temperatures within the
operating limitations established for the
engine during takeoff operation. Use is
limited to two periods, no longer than
10 minutes each under one engine
inoperative (OEI) conditions or 5
minutes each under AEO conditions in
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Fmt 4702
Sfmt 4702
30801
any one flight for a maximum
accumulated usage of 20 minutes in any
one flight. Each flight where the Rated
TOTHAT is used must be followed by
mandatory inspection and maintenance
actions.
2. Part 33
Requirements
In addition to the airworthiness
standards in 14 CFR part 33, effective
February 1, 1965, amendments 33–1
through 33–34 applicable to the engine
and the Rated TOTHAT, the following
special conditions apply:
(a) Section 33.4, Instructions for
Continued Airworthiness.
(1) The ALS must prescribe the
mandatory post-flight inspections and
maintenance actions associated with
any use of the Rated TOTHAT.
(2) The applicant must validate the
adequacy of the inspections and
maintenance actions required under
paragraph 2(a)(1) of these special
conditions.
(3) The applicant must establish an
in-service engine evaluation program to
ensure the continued adequacy of the
instructions for mandatory post-flight
inspections and maintenance actions
prescribed under paragraph 2(a)(1) of
these special conditions, and of the data
for thrust assurance procedures required
by paragraph 2(b)(2) of these special
conditions. The program must include
service engine tests or equivalent
service engine test experience on
engines of similar design and
evaluations of service usage of the Rated
TOTHAT.
(b) Section 33.5, Instruction manual
for installing and operating the engine.
(1) Installation Instructions:
(i) The applicant must identify the
means, or provisions for means,
provided in compliance with the
requirements of paragraph 2(e) of these
special conditions.
(ii) The applicant must specify that
the engine thrust control system
automatically resets the thrust on the
operating engine to the Rated TOTHAT
level when one engine fails during
takeoff at specified altitudes and
temperatures.
(iii) The applicant must specify that
the Rated TOTHAT is available by
manual crew selection at specified
altitudes and temperatures in AEO
conditions.
(2) Operating Instructions: The
applicant must provide data on engine
performance characteristics and
variability to enable the airplane
manufacturer to establish airplane
thrust assurance procedures.
(c) Section 33.7, Engine ratings and
operating limitations.
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03JYP1
sradovich on DSK3GMQ082PROD with PROPOSALS
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Federal Register / Vol. 82, No. 126 / Monday, July 3, 2017 / Proposed Rules
(1) Rated TOTHAT and the associated
operating limitations are established as
follows:
(i) The thrust is the same as the
engine takeoff rated thrust with
extended flat rating corner point.
(ii) The rotational speed limits are the
same as those associated with the
engine takeoff rated thrust.
(iii) The applicant must establish a
gas temperature steady-state limit and, if
necessary, a transient gas over
temperature limit for which the
duration is no longer than 30 seconds.
(iv) The use is limited to two periods
of no longer than 10 minutes each under
OEI conditions or 5 minutes each under
AEO conditions in any one flight, for a
maximum accumulated usage of 20
minutes in any one flight. Each flight
where the Rated TOTHAT is used must
be followed by mandatory inspections
and maintenance actions prescribed by
paragraph 2(a)(1) of these special
conditions.
(2) The applicant must propose
language to include in the type
certificate data sheet specified in § 21.41
for the following:
(i) Rated TOTHAT and associated
limitations.
(ii) As required by § 33.5(b), Operating
instructions, include a note stating that
‘‘Rated Takeoff Thrust at High Ambient
Temperature (Rated TOTHAT) means
the approved engine thrust developed
under specified altitudes and
temperatures within the operating
limitations established for the engine.
Use is limited to two periods, no longer
than 10 minutes each under OEI
conditions or 5 minutes each under
AEO conditions in any one flight, for a
maximum accumulated usage of 20
minutes in any one flight. Each flight
where the Rated TOTHAT is used must
be followed by mandatory inspection
and maintenance actions.’’
(iii) As required by § 33.5(b),
Operating instructions, include a note
stating that the engine thrust control
system automatically resets the thrust
on the operating engine to the Rated
TOTHAT level when one engine fails
during takeoff at specified altitudes and
temperatures, and the Rated TOTHAT is
available by manual selection when all
engines are operational during takeoff at
specified altitudes and temperatures.
(d) Section 33.28, Engine Control
Systems.
The engine must incorporate a means,
or a provision for a means, for automatic
availability and automatic control of the
Rated TOTHAT under OEI conditions
and must permit manual activation of
the Rated TOTHAT under AEO
conditions.
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(e) Section 33.29, Instrument
connection.
The engine must:
(1) Have means, or provisions for
means, to alert the pilot when the Rated
TOTHAT is in use, when the event
begins and when the time interval
expires.
(2) Have means, or provision for
means, which cannot be reset in flight,
to:
(i) Automatically record each use and
duration of the Rated TOTHAT, and
(ii) Alert maintenance personnel that
the engine has been operated at the
Rated TOTHAT and permit retrieval of
recorded data.
(3) Have means, or provision for
means, to enable routine verification of
the proper operation of the means in
paragraph 2(e)(1) and (e)(2) of these
special conditions.
(f) Section 33.85(b), Calibration tests.
The applicant must base the
calibration test on the thrust check at
the end of the endurance test required
by § 33.87 of these special conditions.
(g) Section 33.87, Endurance test.
(1) In addition to the applicable
requirements of § 33.87(a):
(i) The § 33.87 endurance test must be
modified as follows:
(A) Modify the thirty minute test
cycle at the rated takeoff thrust in
§ 33.87(b)(2)(ii) to run one minute at
rated takeoff thrust, followed by five
minutes at the Rated TOTHAT, followed
by the rated takeoff thrust for the
remaining twenty-four minutes.
(B) The modified thirty minute period
described above in paragraph
2(g)(1)(i)(A) must be repeated ten times
in cycles 16 through 25 of the § 33.87
endurance test.
(2) After completion of the tests
required by § 33.87(b), as modified in
paragraph 2(g)(1)(i) above, and without
intervening disassembly, except as
needed to replace those parts described
as consumables in the ICA, the
applicant must conduct the following
test sequence for a total time of not less
than 120 minutes:
(i) Ten minutes at Rated TOTHAT.
(ii) Eighty-eight minutes at rated
maximum continuous thrust.
(iii) One minute at 50 percent of rated
takeoff thrust.
(iv) Ten minutes at Rated TOTHAT.
(v) Ten minutes at rated maximum
continuous thrust.
(vi) One minute at flight idle.
(3) The test sequence of § 33.87(b)(1)
through (6) of these special conditions
must be run continuously. If a stop
occurs during these tests, the
interrupted sequence must be repeated
unless the applicant shows that the
severity of the test would not be
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Fmt 4702
Sfmt 4702
reduced if the current tests were
continued.
(4) Where the engine characteristics
are such that acceleration to the Rated
TOTHAT results in a transient over
temperature in excess of the steady-state
temperature limit identified in
paragraph 2(c)(1)(iii) of these special
conditions, the transient gas
overtemperature must be applied to
each acceleration to the Rated TOTHAT
of the test sequence in paragraph 2(g)(2)
of these special conditions.
(h) Section 33.93, Teardown
inspection.
The applicant must perform the
teardown inspection required by
§ 33.93(a), after completing the
endurance test prescribed by § 33.87 of
these special conditions.
(i) Section 33.201, Design and test
requirements for Early ETOPS
eligibility.
In addition to the requirements of
§ 33.201(c)(1), the simulated ETOPS
mission cyclic endurance test must
include two cycles of 10 minute
duration, each at the Rated TOTHAT;
one before the last diversion cycle and
one at the end of the ETOPS test.
Issued in Burlington, Massachusetts, on
June 13, 2017.
Carlos A. Pestana,
Acting Assistant Manager, Engine and
Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 2017–14043 Filed 6–29–17; 4:15 pm]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2017–0659; Directorate
Identifier 2017–CE–014–AD]
RIN 2120–AA64
Airworthiness Directives; Rockwell
Collins, Inc. Traffic Surveillance
System Processing Unit
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
We propose to adopt a new
airworthiness directive (AD) for certain
Rockwell Collins, Inc. TSS–4100 Traffic
Surveillance System Processing Units
that incorporate TSSA–4100 Field
Loadable Software (FLS) Rockwell
Collins part numbers 810–0052–002/
–003/–010/–011/–012/–100/–101 and
are installed on airplanes. This
proposed AD was prompted by five
SUMMARY:
E:\FR\FM\03JYP1.SGM
03JYP1
Agencies
[Federal Register Volume 82, Number 126 (Monday, July 3, 2017)]
[Proposed Rules]
[Pages 30800-30802]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-14043]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 33
[Docket No. FAA-2017-0586; Notice No. 33-17-01-SC]
Special Conditions: Safran Aircraft Engines, Silvercrest-2 SC-2D;
Rated Takeoff Thrust at High Ambient Temperature
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This action proposes special conditions for the Safran
Aircraft Engines (SAE), Silvercrest-2 SC-2D engine model. This engine
will have a novel or unusual design feature associated with an
additional takeoff rating that increases the exhaust gas temperature
(EGT) limit to maintain takeoff thrust in certain high ambient
temperature conditions for a maximum accumulated usage of 20 minutes in
any one flight. The applicable airworthiness regulations do not contain
adequate or appropriate safety standards for this design feature. These
proposed special conditions contain the additional safety standards
that the Administrator considers necessary to establish a level of
safety equivalent to that established by the existing airworthiness
standards.
DATES: Send your comments on or before July 6, 2017.
ADDRESSES: Send comments identified by docket number [FAA-2017-0586]
using any of the following methods:
Federal eRegulations Portal: Go to https://www.regulations.gov and follow the online instructions for sending your
comments electronically.
Mail: Send comments to Docket Operations, M-30, U.S.
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room
W12-140, West Building Ground Floor, Washington, DC, 20590-0001.
Hand Delivery of Courier: Take comments to Docket
Operations in Room W12-140 of the West Building Ground Floor at 1200
New Jersey Avenue SE., Washington, DC, between 8 a.m., and 5 p.m.,
Monday through Friday, except Federal holidays.
Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: In accordance with 5 U.S.C. 553(c), DOT solicits comments
from the public to better inform its rulemaking process. DOT posts
these comments without edit, including any personal information the
commenter provides, to https://www.regulations.gov, as described in the
system of records notice (DOT/ALL-14 FDMS), which can be reviewed at
https://www.transportation.gov/privacy.
Docket: Background documents or comments received may be read at
https://www.regulations.gov at any time. Follow the online instructions
for accessing the docket or go to the Docket Operations Room in W12-140
of the West Building Ground Floor at 1200 New Jersey Avenue SE.,
Washington, DC, between 9 a.m., and 5 p.m., Monday through Friday,
except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Tara Fitzgerald, ANE-112, Engine and
Propeller Directorate, Aircraft Certification Service, 1200 District
Avenue, Burlington, Massachusetts, 01803-5213; telephone (781) 238-
7130; facsimile (781) 238-7199; email Tara.Fitzgerald@faa.gov.
SUPPLEMENTARY INFORMATION:
Comments Invited
Certification of the Silvercrest-2 SC-2D engine model is currently
scheduled for August 2018. The substance of these special conditions
has been subject to the notice and public comment procedure. Therefore,
because a delay would significantly affect the applicant's
certification of the engine, we are shortening the public comment
period to end on July 6, 2017.
We invite interested persons to participate in this rulemaking by
submitting written comments, data, or views. The agency also invites
comments relating to the economic, environmental, energy, or federalism
impacts that might result from adopting the proposals in this document.
The most helpful comments reference a specific portion of the proposed
special conditions, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments, commenters should send only one copy of written
comments, or if comments are filed electronically, commenters should
submit only one time.
We will file in the docket all comments we receive, as well as a
report summarizing each substantive public contact with FAA personnel
concerning this proposed rulemaking. Before acting on this special
condition, we will consider all comments we receive on or before the
closing date for comments. We will consider comments filed after the
comment period has closed if it is possible to do so without incurring
expense or delay. We may change these special conditions based on the
comments we receive.
Background
On April 19, 2011, SNECMA, now known as SAE, applied for a type
certificate for the Silvercrest-2 SC-2D engine model. On April 30,
2014, SAE requested an extension to their original type certificate
application, which the FAA granted through June 30, 2015. On May 26,
2015, SAE requested another extension to their type certificate
application, which the FAA granted through September 30, 2018.
SAE proposed an additional takeoff rating to maintain takeoff
thrust in certain high ambient temperature conditions with all engines
operating (AEO) for the Silvercrest-2 SC-2D engine model. Therefore,
the Silvercrest-2 SC-2D engine model would have two different takeoff
ratings. The first rating corresponds with the rated takeoff thrust of
the engine. The second takeoff rating maintains the takeoff thrust in
certain high ambient temperature conditions. This additional takeoff
rating is named ``Rated Takeoff Thrust at High Ambient Temperature''
(Rated TOTHAT). The Rated TOTHAT is an approved engine thrust developed
under specified altitudes and temperatures within the operating
limitations established for the engine during takeoff operation for a
maximum usage of 20 minutes in any one flight.
Type Certification Basis
Under the provisions of title 14, Code of Federal Regulations (14
CFR) 21.17, SAE must show that the Silvercrest-2 SC-2D meets the
applicable provisions of 14 CFR part 33, as amended by Amendments 33-1
through 33-34 in effect on the date of application.
If the FAA finds that the applicable airworthiness regulations do
not contain adequate or appropriate safety standards for the
Silvercrest-2 SC-2D engine model, because of a novel or unusual design
feature, special conditions are prescribed under the provisions of
Sec. 21.16.
Special conditions are initially applicable to the model for which
they are issued. Should the type certificate for that model be amended
later to include any other model that
[[Page 30801]]
incorporates the same or similar novel or unusual design feature, the
special conditions would also apply to the other model under Sec.
21.101.
In addition to complying with the applicable product airworthiness
regulations and the requirements of the special conditions, the
Silvercrest-2 SC-2D engine model must comply with the fuel venting and
exhaust emission requirements of 14 CFR part 34.
The FAA issues special conditions, as defined in 14 CFR 11.19, in
accordance with Sec. 11.38, and they become part of the type
certification basis under Sec. 21.17(a)(2).
Novel or Unusual Design Features
The Silvercrest-2 SC-2D engine model will incorporate a novel or
unusual design feature, referred to as ``Rated TOTHAT''. This
additional takeoff rating increases the EGT limit to maintain takeoff
thrust in certain high ambient temperature conditions for a maximum of
20 minutes in any one flight.
Discussion
The Rated TOTHAT is designed for use during takeoff in specified
high altitudes and high ambient temperature conditions to maintain
thrust during takeoff for a maximum of 20 minutes in any one flight.
These proposed special conditions contain additional mandatory post-
flight inspection and maintenance action requirements associated with
any use of the Rated TOTHAT. These requirements add a rating definition
in part 1.1 and mandate mandatory inspections in the instructions for
continued airworthiness (ICA); instructions for installing and
operating the engine; engine rating and operating limitations;
instrument connection; and endurance testing.
The current requirements of the endurance test under Sec. 33.87
represent a typical airplane flight profile and the severity of the
takeoff rating. Therefore, the endurance test under Sec. 33.87 covers
normal, all-engines-operating takeoff conditions for which the engine
control system limits the engine to the takeoff thrust rating. It is
intended to represent the airplane flight profile during takeoff under
specified ambient temperatures for a time until the mandatory
inspection and maintenance actions can be performed.
These proposed special conditions require additional test cycles
that include at least a 150 hours of engine operation as specified in
Sec. 33.87(a), to demonstrate the engine is capable of performing the
Rated TOTHAT rating during AEO conditions without disassembly or
modification.
The associated engine deterioration, after use of the Rated TOTHAT,
is not known without the intervening mandatory inspections in these
special conditions. These mandatory inspections ensure the engine will
continue to comply with its certification basis, which includes these
proposed special conditions, after any use of the Rated TOTHAT. The
applicant is expected to assess the deterioration from use of the Rated
TOTHAT. The airworthiness limitations section (ALS) must prescribe the
mandatory post-flight inspections and maintenance actions associated
with any use of the Rated TOTHAT.
These requirements maintain a level of safety equivalent to the
level intended by the applicable airworthiness standards in effect on
the date of application.
Applicability
As discussed above, these proposed special conditions are
applicable to the Silvercrest-2 SC-2D engine model. Should SAE apply at
a later date for a change to the type certificate to include another
model incorporating the same novel or unusual design feature, the
special conditions would apply to that model as well.
Conclusion
This action affects only the Rated TOTHAT features on the
Silvercrest-2 SC-2D engine model. It is not a rule of general
applicability and applies only to SAE, who requested FAA approval of
this engine feature.
List of Subjects in 14 CFR Part 33
Aircraft, Engines, Aviation safety, Reporting and recordkeeping
requirements.
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, and 44704.
The Proposed Special Conditions
Accordingly, the FAA proposes, the following special conditions as
part of the type certification basis for SAE, Silvercrest-2 SC-2D
engine model.
1. Part 1 Definition
``Rated Take-off Thrust at High Ambient Temperature'' (Rated
TOTHAT) means the approved engine thrust developed under specified
altitudes and temperatures within the operating limitations established
for the engine during takeoff operation. Use is limited to two periods,
no longer than 10 minutes each under one engine inoperative (OEI)
conditions or 5 minutes each under AEO conditions in any one flight for
a maximum accumulated usage of 20 minutes in any one flight. Each
flight where the Rated TOTHAT is used must be followed by mandatory
inspection and maintenance actions.
2. Part 33 Requirements
In addition to the airworthiness standards in 14 CFR part 33,
effective February 1, 1965, amendments 33-1 through 33-34 applicable to
the engine and the Rated TOTHAT, the following special conditions
apply:
(a) Section 33.4, Instructions for Continued Airworthiness.
(1) The ALS must prescribe the mandatory post-flight inspections
and maintenance actions associated with any use of the Rated TOTHAT.
(2) The applicant must validate the adequacy of the inspections and
maintenance actions required under paragraph 2(a)(1) of these special
conditions.
(3) The applicant must establish an in-service engine evaluation
program to ensure the continued adequacy of the instructions for
mandatory post-flight inspections and maintenance actions prescribed
under paragraph 2(a)(1) of these special conditions, and of the data
for thrust assurance procedures required by paragraph 2(b)(2) of these
special conditions. The program must include service engine tests or
equivalent service engine test experience on engines of similar design
and evaluations of service usage of the Rated TOTHAT.
(b) Section 33.5, Instruction manual for installing and operating
the engine.
(1) Installation Instructions:
(i) The applicant must identify the means, or provisions for means,
provided in compliance with the requirements of paragraph 2(e) of these
special conditions.
(ii) The applicant must specify that the engine thrust control
system automatically resets the thrust on the operating engine to the
Rated TOTHAT level when one engine fails during takeoff at specified
altitudes and temperatures.
(iii) The applicant must specify that the Rated TOTHAT is available
by manual crew selection at specified altitudes and temperatures in AEO
conditions.
(2) Operating Instructions: The applicant must provide data on
engine performance characteristics and variability to enable the
airplane manufacturer to establish airplane thrust assurance
procedures.
(c) Section 33.7, Engine ratings and operating limitations.
[[Page 30802]]
(1) Rated TOTHAT and the associated operating limitations are
established as follows:
(i) The thrust is the same as the engine takeoff rated thrust with
extended flat rating corner point.
(ii) The rotational speed limits are the same as those associated
with the engine takeoff rated thrust.
(iii) The applicant must establish a gas temperature steady-state
limit and, if necessary, a transient gas over temperature limit for
which the duration is no longer than 30 seconds.
(iv) The use is limited to two periods of no longer than 10 minutes
each under OEI conditions or 5 minutes each under AEO conditions in any
one flight, for a maximum accumulated usage of 20 minutes in any one
flight. Each flight where the Rated TOTHAT is used must be followed by
mandatory inspections and maintenance actions prescribed by paragraph
2(a)(1) of these special conditions.
(2) The applicant must propose language to include in the type
certificate data sheet specified in Sec. 21.41 for the following:
(i) Rated TOTHAT and associated limitations.
(ii) As required by Sec. 33.5(b), Operating instructions, include
a note stating that ``Rated Takeoff Thrust at High Ambient Temperature
(Rated TOTHAT) means the approved engine thrust developed under
specified altitudes and temperatures within the operating limitations
established for the engine. Use is limited to two periods, no longer
than 10 minutes each under OEI conditions or 5 minutes each under AEO
conditions in any one flight, for a maximum accumulated usage of 20
minutes in any one flight. Each flight where the Rated TOTHAT is used
must be followed by mandatory inspection and maintenance actions.''
(iii) As required by Sec. 33.5(b), Operating instructions, include
a note stating that the engine thrust control system automatically
resets the thrust on the operating engine to the Rated TOTHAT level
when one engine fails during takeoff at specified altitudes and
temperatures, and the Rated TOTHAT is available by manual selection
when all engines are operational during takeoff at specified altitudes
and temperatures.
(d) Section 33.28, Engine Control Systems.
The engine must incorporate a means, or a provision for a means,
for automatic availability and automatic control of the Rated TOTHAT
under OEI conditions and must permit manual activation of the Rated
TOTHAT under AEO conditions.
(e) Section 33.29, Instrument connection.
The engine must:
(1) Have means, or provisions for means, to alert the pilot when
the Rated TOTHAT is in use, when the event begins and when the time
interval expires.
(2) Have means, or provision for means, which cannot be reset in
flight, to:
(i) Automatically record each use and duration of the Rated TOTHAT,
and
(ii) Alert maintenance personnel that the engine has been operated
at the Rated TOTHAT and permit retrieval of recorded data.
(3) Have means, or provision for means, to enable routine
verification of the proper operation of the means in paragraph 2(e)(1)
and (e)(2) of these special conditions.
(f) Section 33.85(b), Calibration tests.
The applicant must base the calibration test on the thrust check at
the end of the endurance test required by Sec. 33.87 of these special
conditions.
(g) Section 33.87, Endurance test.
(1) In addition to the applicable requirements of Sec. 33.87(a):
(i) The Sec. 33.87 endurance test must be modified as follows:
(A) Modify the thirty minute test cycle at the rated takeoff thrust
in Sec. 33.87(b)(2)(ii) to run one minute at rated takeoff thrust,
followed by five minutes at the Rated TOTHAT, followed by the rated
takeoff thrust for the remaining twenty-four minutes.
(B) The modified thirty minute period described above in paragraph
2(g)(1)(i)(A) must be repeated ten times in cycles 16 through 25 of the
Sec. 33.87 endurance test.
(2) After completion of the tests required by Sec. 33.87(b), as
modified in paragraph 2(g)(1)(i) above, and without intervening
disassembly, except as needed to replace those parts described as
consumables in the ICA, the applicant must conduct the following test
sequence for a total time of not less than 120 minutes:
(i) Ten minutes at Rated TOTHAT.
(ii) Eighty-eight minutes at rated maximum continuous thrust.
(iii) One minute at 50 percent of rated takeoff thrust.
(iv) Ten minutes at Rated TOTHAT.
(v) Ten minutes at rated maximum continuous thrust.
(vi) One minute at flight idle.
(3) The test sequence of Sec. 33.87(b)(1) through (6) of these
special conditions must be run continuously. If a stop occurs during
these tests, the interrupted sequence must be repeated unless the
applicant shows that the severity of the test would not be reduced if
the current tests were continued.
(4) Where the engine characteristics are such that acceleration to
the Rated TOTHAT results in a transient over temperature in excess of
the steady-state temperature limit identified in paragraph 2(c)(1)(iii)
of these special conditions, the transient gas overtemperature must be
applied to each acceleration to the Rated TOTHAT of the test sequence
in paragraph 2(g)(2) of these special conditions.
(h) Section 33.93, Teardown inspection.
The applicant must perform the teardown inspection required by
Sec. 33.93(a), after completing the endurance test prescribed by Sec.
33.87 of these special conditions.
(i) Section 33.201, Design and test requirements for Early ETOPS
eligibility.
In addition to the requirements of Sec. 33.201(c)(1), the
simulated ETOPS mission cyclic endurance test must include two cycles
of 10 minute duration, each at the Rated TOTHAT; one before the last
diversion cycle and one at the end of the ETOPS test.
Issued in Burlington, Massachusetts, on June 13, 2017.
Carlos A. Pestana,
Acting Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2017-14043 Filed 6-29-17; 4:15 pm]
BILLING CODE 4910-13-P