Special Conditions: Pilatus Aircraft Ltd., PC-24; Electronic Engine Control (EEC), 32616-32618 [2017-14936]
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32616
Federal Register / Vol. 82, No. 135 / Monday, July 17, 2017 / Rules and Regulations
The Special Conditions
Accordingly, pursuant to the authority
delegated to me by the Administrator,
the following special conditions are
issued as part of the type certification
basis for Pilatus Aircraft Ltd. PC–24
airplanes.
■
1. Pressure Fueling System
For pressure fueling systems, in
addition to § 23.979, the following
applies:
The airplane defueling system—not
including fuel tanks and fuel tank
vents—must withstand an ultimate load
that is 2.0 times the load arising from
the maximum permissible defueling
pressure—positive or negative—at the
airplane fueling connection.
Issued in Kansas City, Missouri, on July 6,
2017.
Kelly Broadway,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2017–14937 Filed 7–14–17; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. FAA–2017–0702; Special
Conditions No. 23–282–SC]
Special Conditions: Pilatus Aircraft
Ltd., PC–24; Electronic Engine Control
(EEC)
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Pilatus Aircraft Ltd. PC–
24 airplane. This airplane will have a
novel or unusual design features
associated with installation of an
electronic engine control. The
applicable airworthiness regulations do
not contain adequate or appropriate
safety standards for this design feature.
These 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: These special conditions are
effective July 17, 2017 and are
applicable beginning July 6, 2017.
ADDRESSES: Send comments identified
by docket number FAA–2017–0702
using any of the following methods:
b Federal eRegulations Portal: Go to
https://www.regulations.gov and follow
jstallworth on DSK7TPTVN1PROD with RULES
SUMMARY:
VerDate Sep<11>2014
14:51 Jul 14, 2017
Jkt 241001
the online instructions for sending your
comments electronically.
b 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.
b 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 9
a.m., and 5 p.m., Monday through
Friday, except Federal holidays.
b Fax: Fax comments to Docket
Operations at 202–493–2251.
Privacy: The FAA will post all
comments it receives, without change,
to https://regulations.gov, including any
personal information the commenter
provides. Using the search function of
the docket Web site, anyone can find
and read the electronic form of all
comments received into any FAA
docket, including the name of the
individual sending the comment (or
signing the comment for an association,
business, labor union, etc.). DOT’s
complete Privacy Act Statement can be
found in the Federal Register published
on April 11, 2000 (65 FR 19477–19478),
as well as at https://DocketsInfo.dot.gov.
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 in Room 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: Jeff
Pretz, ACE–111, Federal Aviation
Administration, Small Airplane
Directorate, Aircraft Certification
Service, 901 Locust Street, Kansas City,
MO 64106; telephone (816) 329–3239;
facsimile (816) 329–4090.
SUPPLEMENTARY INFORMATION: The FAA
has determined, in accordance with 5
U.S.C. 553(b)(3)(B) and 553(d)(3), that
notice and opportunity for prior public
comment hereon are unnecessary
because the substance of these special
conditions has been subject to the
public comment process in several prior
instances with no substantive comments
received. The FAA therefore finds good
cause exists for making these special
conditions effective upon issuance.
Special condition
No.2
23–264–SC .......
PO 00000
Frm 00004
Company/airplane model
Honda Aircraft Company/
Model HA–420.
Fmt 4700
Sfmt 4700
Special condition
No.2
23–267–SC .......
23–268–SC .......
Company/airplane model
Cirrus Design Corporation/
Model SF50.
Korean Aircraft Industries/
Model K–100.
Comments Invited
We invite interested people to take
part in this rulemaking by sending
written comments, data, or views. The
most helpful comments reference a
specific portion of the special
conditions, explain the reason for any
recommended change, and include
supporting data. We ask that you send
us two copies of written comments.
We will consider all comments we
receive on or before the closing date for
comments. We will consider comments
filed late 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 July 9th 2012, Pilatus Aircraft Ltd.
applied for a type certificate for their
new PC–24 airplane. The PC–24 is an
aluminum pressurized low-wing
business jet with a T-tail configuration
and retractable undercarriage designed
to meet the commuter category
requirements of part 23. Two Williams
International FJ44–4A Turbofan engines
rated at 3,400 pounds (lbs.) of take-off
thrust, situated in nacelles on each side
of the rear fuselage power the PC–24.
The PC–24 will have a Maximum Takeoff Weight (MTOW) of 17,200 pounds
(7,802 kilograms). It has a maximum
seating capacity of up to ten passengers
and one or two pilots. The airplane will
be certificated for day and night Visual
Flight Rules and Instrument Flight
Rules and approval for flight into
known icing.
The PC–24 airplane’s two Williams
International FJ44–4A turbofan engines
each use an electronic engine control
system (EEC)—commonly referred to as
a Full Authority Digital Engine Control
(FADEC)—instead of a traditional
mechanical control system. Even though
the engine control system will be
certificated as part of the engine, the
installation of an engine with an
electronic control system requires
evaluation due to critical environmental
effects and possible effects on or by
other airplane systems. Examples of
critical environmental effects include—
• Indirect effects of lightning;
• Radio interference with other
airplane electronic systems; and
2 See https://rgl.faa.gov/ to view the listed special
conditions.
E:\FR\FM\17JYR1.SGM
17JYR1
Federal Register / Vol. 82, No. 135 / Monday, July 17, 2017 / Rules and Regulations
jstallworth on DSK7TPTVN1PROD with RULES
• Shared engine, airplane data, and
power sources.
The regulatory requirements in part
23 for evaluating the installation of
complex systems—including electronic
systems and critical environmental
effects—are contained in §§ 23.1306,
23.1308, and 23.1309. However, when
§ 23.1309 was published, the use of
electronic control systems for engines
was not envisioned. The integral nature
of these systems makes it necessary to
properly evaluate the airplane functions
included in the EEC and ensure the
installation does not degrade the EEC
reliability, both of which are approved
under 14 CFR part 33. Sections
23.1306(a) and 23.1308(a) apply to the
EEC to ensure it remains equivalent to
a mechanical system, which is not
generally susceptible to the HIRF and
lightning environments.
In some cases, the airplane—in which
the engine is being installed—will
determine a higher classification than
the engine controls are certificated for;
requiring the EEC systems be analyzed
at a higher classification. As of
November 2005, EEC special conditions
mandated the § 23.1309 classification
for loss of EEC control as catastrophic
for any airplane. This is not to imply an
engine failure is classified as
catastrophic, but that the EEC must
provide an equivalent reliability to
mechanical engine controls. In addition,
§§ 23.1141(e) and 25.901(b)(2) are
applied to provide the fault tolerant
design requirements of turbine engine
mechanical controls to the EEC and
ensure adequate EEC inspection and
maintenance intervals.
Type Certification Basis
Under the provisions of 14 CFR 21.17,
Pilatus Aircraft Ltd., must show that the
PC–24 meets the applicable provisions
of part 23, as amended by amendments
23–1 through 23–62 thereto.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 23) do not contain
adequate or appropriate safety standards
for the PC–24 because of a novel or
unusual design feature, special
conditions are prescribed under the
provisions of § 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, the PC–24 must comply
with the fuel vent and exhaust emission
requirements of 14 CFR part 34, the
noise certification requirements of 14
CFR part 36, and the FAA must issue a
finding of regulatory adequacy pursuant
to section 611 of Public Law 92–574, the
‘‘Noise Control Act of 1972.’’
The FAA issues special conditions, as
defined in § 11.19, under § 11.38 and
VerDate Sep<11>2014
14:51 Jul 14, 2017
Jkt 241001
they become part of the type
certification basis under § 21.17(a)(2).
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
incorporates the same novel or unusual
design feature, the FAA would apply
these special conditions to the other
models under § 21.101.
Novel or Unusual Design Features
The PC–24 will incorporate the
following novel or unusual design
features:
Electronic Engine Control System.
Discussion
As discussed in the ‘‘Background’’
section, the PC–24 will use an EEC
system instead of a traditional
mechanical control system, which is a
novel design for this type of airplane.
The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for this
design feature. Mandating a structured
assessment to determine potential
installation issues mitigates the
concerns that the addition of an
electronic engine control may produce
failure conditions not previously
considered.
Applicability
As discussed above, these special
conditions are applicable to the PC–24.
Should Pilatus Aircraft Ltd. apply at a
later date for a change to the type
certificate to include another model on
the same type certificate incorporating
the same novel or unusual design
feature, the FAA would apply these
special conditions to that model as well.
Conclusion
This action affects only certain novel
or unusual design features on one model
of airplanes. It is not a rule of general
applicability and it affects only the
applicant who applied to the FAA for
approval of these features on the
airplane.
The substance of these special
conditions has been subjected to the
notice and comments period in several
prior instances—identified above—and
has been derived without substantive
change from those previously issued. It
is unlikely that prior public comment
would result in a significant change
from the substance contained herein.
Therefore, notice and opportunity for
prior public comments hereon are
unnecessary and the FAA finds good
cause, in accordance with 5 U.S.C.
553(b)(3)(B) and 553(d)(3), making these
special conditions effective upon
PO 00000
Frm 00005
Fmt 4700
Sfmt 4700
32617
issuance. The FAA is requesting
comments to allow interested persons to
submit views that may not have been
submitted in response to the prior
opportunities for comment described
above.
List of Subjects in 14 CFR Part 23
Aircraft, Aviation safety, Signs and
symbols.
Citation
The authority citation for these
special conditions is as follows:
Authority: 49 U.S.C. 106(f), 106(g), 40113
and 44701; 14 CFR 21.16 and 21.17; and 14
CFR 11.38 and 11.19.
The Special Conditions
Accordingly, pursuant to the authority
delegated to me by the Administrator,
the following special conditions are
issued as part of the type certification
basis for Pilatus Aircraft Ltd. PC–24
airplanes.
1. Electronic Engine Control.
(a) For electronic engine control
system installations, it must be
established that no single failure or
malfunction or probable combinations
of failures of EEC system components
will have an effect on the system—as
installed in the airplane—that causes
the loss-of-thrust-control (LOTC)
probability of the system to exceed
those allowed in part 33 certification.
(b) Electronic engine control system
installations must be evaluated for
environmental and atmospheric
conditions, including lightning. The
EEC system lightning and HIRF effects
that result in LOTC should be
considered catastrophic.
(c) The components of the installation
must be constructed, arranged, and
installed to ensure their continued safe
operation between normal inspections
or overhauls.
(d) Functions incorporated into any
electronic engine control that make it
part of any equipment, system, or
installation whose functions are beyond
that of basic engine control, and which
may also introduce system failures and
malfunctions, are not exempt from
§ 23.1309 and must be shown to meet
part 23 levels of safety as derived from
§ 23.1309. Part 33 certification data—if
applicable—may be used to show
compliance with any part 23
requirements. If part 33 data is to be
used to substantiate compliance with
part 23 requirements, then the applicant
must provide this data to show
compliance.
■
Note: The term ‘‘probable’’ in the context
of ‘‘probable combination of failures’’ does
not have the same meaning as in AC
23.1309–1E, ‘‘System Safety Analysis and
E:\FR\FM\17JYR1.SGM
17JYR1
32618
Federal Register / Vol. 82, No. 135 / Monday, July 17, 2017 / Rules and Regulations
Assessment for Part 23 Airplanes.’’ The term
‘‘probable’’ in ‘‘probable combination of
failures’’ means ‘‘foreseeable,’’ or—in AC
23.1309–1E terms—‘‘not extremely
improbable.’’
Issued in Kansas City, Missouri on July 6,
2017.
Kelly Broadway,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2017–14936 Filed 7–14–17; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. FAA–2017–0703; Special
Conditions No. 23–283–SC]
Special Conditions: Pilatus Aircraft
Ltd., PC–24, Autothrust System
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Pilatus Aircraft Ltd. PC–
24 airplane. This airplane will have a
novel or unusual design feature
associated with installation of an
autothrust system. The applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for this design feature. These 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: These special conditions are
effective July 17, 2017, and are
applicable July 6, 2017.
ADDRESSES: Send comments identified
by docket number FAA–2017–0703
using any of the following methods:
b Federal eRegulations Portal: Go to
https://www.regulations.gov and follow
the online instructions for sending your
comments electronically.
b 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.
b 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 9
a.m., and 5 p.m., Monday through
Friday, except Federal holidays.
b Fax: Fax comments to Docket
Operations at 202–493–2251.
jstallworth on DSK7TPTVN1PROD with RULES
SUMMARY:
VerDate Sep<11>2014
14:51 Jul 14, 2017
Jkt 241001
Privacy: The FAA will post all
comments it receives, without change,
to https://regulations.gov, including any
personal information the commenter
provides. Using the search function of
the docket Web site, anyone can find
and read the electronic form of all
comments received into any FAA
docket, including the name of the
individual sending the comment (or
signing the comment for an association,
business, labor union, etc.). DOT’s
complete Privacy Act Statement can be
found in the Federal Register published
on April 11, 2000 (65 FR 19477–19478),
as well as at https://DocketsInfo.dot.gov.
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 in Room 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: Jeff
Pretz, ACE–111, Federal Aviation
Administration, Small Airplane
Directorate, Aircraft Certification
Service, 901 Locust Street, Kansas City,
MO 64106; telephone (816) 329–3239;
facsimile (816) 329–4090.
SUPPLEMENTARY INFORMATION: The FAA
has determined, in accordance with 5
U.S.C. 553(b)(3)(B) and 553(d)(3), that
notice and opportunity for prior public
comment hereon are unnecessary
because the substance of these special
conditions has been subject to the
public comment process in several prior
instances with no substantive comments
received. The FAA therefore finds that
good cause exists for making these
special conditions effective upon
issuance.
Special condition
No.2
Company/airplane model
23–264–SC .......
Honda Aircraft Company/
Model HA–420.
Cirrus Design Corporation/
Model SF50.
Innovative Solutions and
Support Inc./Pilatus Aircraft Ltd., PC–12 Models.
23–272–SC .......
23–281–SC .......
Comments Invited
We invite interested people to take
part in this rulemaking by sending
written comments, data, or views. The
most helpful comments reference a
specific portion of the special
conditions, explain the reason for any
2 See https://rgl.faa.gov/ to review the listed
special conditions.
PO 00000
Frm 00006
Fmt 4700
Sfmt 4700
recommended change, and include
supporting data. We ask that you send
us two copies of written comments.
We will consider all comments we
receive on or before the closing date for
comments. We will consider comments
filed late 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 July 9, 2012, Pilatus Aircraft Ltd.
applied for a type certificate for their
new PC–24 airplane. The PC–24 is an
aluminum pressurized low-wing
business jet with a T-tail configuration
and retractable undercarriage designed
to meet the commuter category
requirements of part 23. Two Williams
International FJ44–4A turbofan engines
rated at 3,400 pounds (lbs.) of take-off
thrust, situated in nacelles on each side
of the rear fuselage power the PC–24.
The PC–24 will have a Maximum Takeoff Weight (MTOW) of 17,200 pounds
(7,802 kilograms). It has a maximum
seating capacity of up to ten passengers
and one or two pilots. The airplane will
be certificated for day and night Visual
Flight Rules, Instrument Flight Rules
and flight into known icing.
The PC–24 is equipped with an
autothrust system—also referred to as an
autothrottle system. The autothrust
system is useable in all phases of flight
from takeoff to decision height on
approach. The system includes speed
and thrust modes along with monitors
to prevent the system from exceeding
engine or airspeed limits. A servo
provides throttle movement, which is
part of each throttle quadrant assembly.
The servo(s) can be overridden by pilot
force or disconnected using the
autothrottle quick disconnect switch on
either thrust control lever, the autopilot
quick disconnect switch on the yoke, or
the autothrottle control switch on the
flight guidance panel.
Type Certification Basis
Under the provisions of 14 CFR 21.17,
Pilatus Aircraft Ltd. must show the PC–
24 meets the applicable provisions of
part 23, as amended by amendments
23–1 through 23–62 thereto.
If the Administrator finds the
applicable airworthiness regulations
(i.e., 14 CFR part 23) do not contain
adequate or appropriate safety standards
for the PC–24 because of a novel or
unusual design feature, special
conditions are prescribed under the
provisions of § 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, the PC–24 must comply
with the fuel vent and exhaust emission
E:\FR\FM\17JYR1.SGM
17JYR1
Agencies
[Federal Register Volume 82, Number 135 (Monday, July 17, 2017)]
[Rules and Regulations]
[Pages 32616-32618]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-14936]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. FAA-2017-0702; Special Conditions No. 23-282-SC]
Special Conditions: Pilatus Aircraft Ltd., PC-24; Electronic
Engine Control (EEC)
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Pilatus Aircraft
Ltd. PC-24 airplane. This airplane will have a novel or unusual design
features associated with installation of an electronic engine control.
The applicable airworthiness regulations do not contain adequate or
appropriate safety standards for this design feature. These 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: These special conditions are effective July 17, 2017 and are
applicable beginning July 6, 2017.
ADDRESSES: Send comments identified by docket number FAA-2017-0702
using any of the following methods:
[squ] Federal eRegulations Portal: Go to https://www.regulations.gov
and follow the online instructions for sending your comments
electronically.
[squ] 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.
[squ] 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 9 a.m., and 5 p.m., Monday through
Friday, except Federal holidays.
[squ] Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: The FAA will post all comments it receives, without
change, to https://regulations.gov, including any personal information
the commenter provides. Using the search function of the docket Web
site, anyone can find and read the electronic form of all comments
received into any FAA docket, including the name of the individual
sending the comment (or signing the comment for an association,
business, labor union, etc.). DOT's complete Privacy Act Statement can
be found in the Federal Register published on April 11, 2000 (65 FR
19477-19478), as well as at https://DocketsInfo.dot.gov.
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 in Room 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: Jeff Pretz, ACE-111, Federal Aviation
Administration, Small Airplane Directorate, Aircraft Certification
Service, 901 Locust Street, Kansas City, MO 64106; telephone (816) 329-
3239; facsimile (816) 329-4090.
SUPPLEMENTARY INFORMATION: The FAA has determined, in accordance with 5
U.S.C. 553(b)(3)(B) and 553(d)(3), that notice and opportunity for
prior public comment hereon are unnecessary because the substance of
these special conditions has been subject to the public comment process
in several prior instances with no substantive comments received. The
FAA therefore finds good cause exists for making these special
conditions effective upon issuance.
------------------------------------------------------------------------
Special condition No.\2\ Company/airplane model
------------------------------------------------------------------------
23-264-SC............................. Honda Aircraft Company/Model HA-
420.
23-267-SC............................. Cirrus Design Corporation/Model
SF50.
23-268-SC............................. Korean Aircraft Industries/Model
K-100.
------------------------------------------------------------------------
Comments Invited
---------------------------------------------------------------------------
\2\ See https://rgl.faa.gov/ to view the listed special
conditions.
---------------------------------------------------------------------------
We invite interested people to take part in this rulemaking by
sending written comments, data, or views. The most helpful comments
reference a specific portion of the special conditions, explain the
reason for any recommended change, and include supporting data. We ask
that you send us two copies of written comments.
We will consider all comments we receive on or before the closing
date for comments. We will consider comments filed late 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 July 9th 2012, Pilatus Aircraft Ltd. applied for a type
certificate for their new PC-24 airplane. The PC-24 is an aluminum
pressurized low-wing business jet with a T-tail configuration and
retractable undercarriage designed to meet the commuter category
requirements of part 23. Two Williams International FJ44-4A Turbofan
engines rated at 3,400 pounds (lbs.) of take-off thrust, situated in
nacelles on each side of the rear fuselage power the PC-24. The PC-24
will have a Maximum Take-off Weight (MTOW) of 17,200 pounds (7,802
kilograms). It has a maximum seating capacity of up to ten passengers
and one or two pilots. The airplane will be certificated for day and
night Visual Flight Rules and Instrument Flight Rules and approval for
flight into known icing.
The PC-24 airplane's two Williams International FJ44-4A turbofan
engines each use an electronic engine control system (EEC)--commonly
referred to as a Full Authority Digital Engine Control (FADEC)--instead
of a traditional mechanical control system. Even though the engine
control system will be certificated as part of the engine, the
installation of an engine with an electronic control system requires
evaluation due to critical environmental effects and possible effects
on or by other airplane systems. Examples of critical environmental
effects include--
Indirect effects of lightning;
Radio interference with other airplane electronic systems;
and
[[Page 32617]]
Shared engine, airplane data, and power sources.
The regulatory requirements in part 23 for evaluating the
installation of complex systems--including electronic systems and
critical environmental effects--are contained in Sec. Sec. 23.1306,
23.1308, and 23.1309. However, when Sec. 23.1309 was published, the
use of electronic control systems for engines was not envisioned. The
integral nature of these systems makes it necessary to properly
evaluate the airplane functions included in the EEC and ensure the
installation does not degrade the EEC reliability, both of which are
approved under 14 CFR part 33. Sections 23.1306(a) and 23.1308(a) apply
to the EEC to ensure it remains equivalent to a mechanical system,
which is not generally susceptible to the HIRF and lightning
environments.
In some cases, the airplane--in which the engine is being
installed--will determine a higher classification than the engine
controls are certificated for; requiring the EEC systems be analyzed at
a higher classification. As of November 2005, EEC special conditions
mandated the Sec. 23.1309 classification for loss of EEC control as
catastrophic for any airplane. This is not to imply an engine failure
is classified as catastrophic, but that the EEC must provide an
equivalent reliability to mechanical engine controls. In addition,
Sec. Sec. 23.1141(e) and 25.901(b)(2) are applied to provide the fault
tolerant design requirements of turbine engine mechanical controls to
the EEC and ensure adequate EEC inspection and maintenance intervals.
Type Certification Basis
Under the provisions of 14 CFR 21.17, Pilatus Aircraft Ltd., must
show that the PC-24 meets the applicable provisions of part 23, as
amended by amendments 23-1 through 23-62 thereto.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 23) do not contain adequate or
appropriate safety standards for the PC-24 because of a novel or
unusual design feature, special conditions are prescribed under the
provisions of Sec. 21.16.
In addition to the applicable airworthiness regulations and special
conditions, the PC-24 must comply with the fuel vent and exhaust
emission requirements of 14 CFR part 34, the noise certification
requirements of 14 CFR part 36, and the FAA must issue a finding of
regulatory adequacy pursuant to section 611 of Public Law 92-574, the
``Noise Control Act of 1972.''
The FAA issues special conditions, as defined in Sec. 11.19, under
Sec. 11.38 and they become part of the type certification basis under
Sec. 21.17(a)(2).
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 incorporates the same novel or
unusual design feature, the FAA would apply these special conditions to
the other models under Sec. 21.101.
Novel or Unusual Design Features
The PC-24 will incorporate the following novel or unusual design
features:
Electronic Engine Control System.
Discussion
As discussed in the ``Background'' section, the PC-24 will use an
EEC system instead of a traditional mechanical control system, which is
a novel design for this type of airplane. The applicable airworthiness
regulations do not contain adequate or appropriate safety standards for
this design feature. Mandating a structured assessment to determine
potential installation issues mitigates the concerns that the addition
of an electronic engine control may produce failure conditions not
previously considered.
Applicability
As discussed above, these special conditions are applicable to the
PC-24. Should Pilatus Aircraft Ltd. apply at a later date for a change
to the type certificate to include another model on the same type
certificate incorporating the same novel or unusual design feature, the
FAA would apply these special conditions to that model as well.
Conclusion
This action affects only certain novel or unusual design features
on one model of airplanes. It is not a rule of general applicability
and it affects only the applicant who applied to the FAA for approval
of these features on the airplane.
The substance of these special conditions has been subjected to the
notice and comments period in several prior instances--identified
above--and has been derived without substantive change from those
previously issued. It is unlikely that prior public comment would
result in a significant change from the substance contained herein.
Therefore, notice and opportunity for prior public comments hereon are
unnecessary and the FAA finds good cause, in accordance with 5 U.S.C.
553(b)(3)(B) and 553(d)(3), making these special conditions effective
upon issuance. The FAA is requesting comments to allow interested
persons to submit views that may not have been submitted in response to
the prior opportunities for comment described above.
List of Subjects in 14 CFR Part 23
Aircraft, Aviation safety, Signs and symbols.
Citation
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(f), 106(g), 40113 and 44701; 14 CFR
21.16 and 21.17; and 14 CFR 11.38 and 11.19.
The Special Conditions
0
Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type certification basis for Pilatus Aircraft Ltd. PC-24 airplanes.
1. Electronic Engine Control.
(a) For electronic engine control system installations, it must be
established that no single failure or malfunction or probable
combinations of failures of EEC system components will have an effect
on the system--as installed in the airplane--that causes the loss-of-
thrust-control (LOTC) probability of the system to exceed those allowed
in part 33 certification.
(b) Electronic engine control system installations must be
evaluated for environmental and atmospheric conditions, including
lightning. The EEC system lightning and HIRF effects that result in
LOTC should be considered catastrophic.
(c) The components of the installation must be constructed,
arranged, and installed to ensure their continued safe operation
between normal inspections or overhauls.
(d) Functions incorporated into any electronic engine control that
make it part of any equipment, system, or installation whose functions
are beyond that of basic engine control, and which may also introduce
system failures and malfunctions, are not exempt from Sec. 23.1309 and
must be shown to meet part 23 levels of safety as derived from Sec.
23.1309. Part 33 certification data--if applicable--may be used to show
compliance with any part 23 requirements. If part 33 data is to be used
to substantiate compliance with part 23 requirements, then the
applicant must provide this data to show compliance.
Note: The term ``probable'' in the context of ``probable
combination of failures'' does not have the same meaning as in AC
23.1309-1E, ``System Safety Analysis and
[[Page 32618]]
Assessment for Part 23 Airplanes.'' The term ``probable'' in
``probable combination of failures'' means ``foreseeable,'' or--in
AC 23.1309-1E terms--``not extremely improbable.''
Issued in Kansas City, Missouri on July 6, 2017.
Kelly Broadway,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2017-14936 Filed 7-14-17; 8:45 am]
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