[Federal Register Volume 82, Number 71 (Friday, April 14, 2017)]
[Proposed Rules]
[Pages 17943-17945]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-07382]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 82, No. 71 / Friday, April 14, 2017 /
Proposed Rules
[[Page 17943]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. FAA-2017-0290; Notice No. 23-17-01-SC]
Special Conditions: Pilatus Aircraft Limited Models PC-12, PC-12/
45, PC-12/47; Autothrust System
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
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SUMMARY: This action proposes a special condition for the Pilatus
Aircraft Limited PC-12, PC-12/45, and PC-12/47 airplanes. These
airplanes, as modified by Innovative Solutions & Support, Inc., will
have a novel or unusual design feature associated with the use of an
autothrust system. The applicable airworthiness regulations do not
contain adequate or appropriate safety standards for this design
feature. This proposed special condition contains the additional safety
standards the Administrator considers necessary to establish a level of
safety equivalent to that established by the existing airworthiness
standards.
DATES: Send your comment on or before May 15, 2017.
ADDRESSES: Send comments identified by docket number FAA-2017-0290
using any of the following methods:
Federal eRegulations Portal: Go to http://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 9 a.m., and 5 p.m.,
Monday through Friday, except Federal holidays.
Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: The FAA will post all comments it receives, without
change, to http://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 http://DocketsInfo.dot.gov.
Docket: Background documents or comments received may be read at
http://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, Federal Aviation
Administration, Small Airplane Directorate, Aircraft Certification
Service, 901 Locust, Room 301, Kansas City, MO 64106; telephone (816)
329-3239; facsimile (816) 329-4090.
SUPPLEMENTARY INFORMATION:
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 April 4, 2016, Innovative Solutions & Support applied for a
supplemental type certificate for installation of an autothrust system
in the PC-12, PC-12/45, and PC-12/47 airplanes. The autothrust system
is capable of setting forward thrust based on operation in either a
pilot selectable torque or airspeed mode. Operation is limited to use
only when above 400 feet AGL after takeoff, and requires disengagement
at decision height (DH) or minimum decision altitude (MDA) on approach.
The PC-12, PC-12/45, and PC-12/47 airplanes are nine-passenger two-
crew, single-engine turbo-propeller airplanes with a 30,000-foot
service ceiling and a maximum takeoff weight of 9,039 to 10,450
pounds--depending on airplane model. These airplanes are powered by a
single Pratt & Whitney PT6A-67 engine.
The Innovative Solutions & Support, Inc., modification installs an
autothrust system in the PC-12, PC-12/45, and PC-12/47 airplanes to
reduce pilot workload. The autothrust system is useable in all phases
of flight from 400 feet AGL after takeoff down to the decision height
on approach. The system includes a torque and airspeed mode along with
monitors to prevent the system from exceeding critical engine or
airspeed limits. A stepper motor provides throttle movement by acting
through a linear actuator, which acts as a link between the stepper
motor and throttle. The pilot can override the linear actuator by
moving the throttle, which automatically disengages the autothrust
system upon disagreement in the expected throttle position versus the
actual position.
Type Certification Basis
Under the provisions of 14 CFR 21.101, Innovative Solutions &
Support must show that the PC-12, PC-12/45, and PC-12/47 airplanes, as
changed, continues to meet the applicable provisions of the regulations
incorporated by reference in Type Certificate No. A78EU. The
regulations incorporated by reference in the type certificate are
commonly referred to as the ``original type certification basis.'' The
regulations incorporated by reference in A78EU are as follows: 14 CFR
part 23, amendments 23-1 through 23-42.\2\
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\2\ See Type Certification Data Sheet A78EU, revision 25,
``Certification Basis'' section for the PC-12, PC-12/45, and PC-12/
47 full certification basis (http://rgl.faa.gov/).
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If the Administrator finds the applicable airworthiness regulations
[[Page 17944]]
(i.e., 14 CFR part 23) do not contain adequate or appropriate safety
standards for the PC-12, PC-12/45, and PC-12/47 airplanes because of a
novel or unusual design feature(s), special conditions are prescribed
under the provisions of Sec. 21.16.
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. 21.101. Special conditions are
initially applicable to the model for which they are issued. Should the
applicant apply for a supplemental type certificate to modify any other
model included on the same type certificate to incorporate the same
novel or unusual design feature, the FAA would apply these special
conditions to the other model under Sec. 21.101.
In addition to the applicable airworthiness regulations and special
conditions, the PC-12, PC-12/45, and PC-12/47 airplanes must comply
with the fuel vent and exhaust emission requirements of 14 CFR part 34
and the noise certification requirements of 14 CFR part 36.
Novel or Unusual Design Features
The PC-12, PC-12/45, and PC-12/47 airplanes will incorporate the
following novel or unusual design features: Autothrust system.
Discussion
As discussed in the summary section, this modification makes use of
an autothrust 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 additional requirements--developed in part--by adapting
relevant portions of 14 CFR 25.1329, Flight guidance systems--
applicable to autothrust systems--along with FAA experience with
similar autothrust systems, mitigates the concerns associated with
installation of the proposed autothrust system.
The FAA has previously issued this proposed special condition to
part 23 turbojet airplanes, but not for turbo-propeller airplanes. The
PC-12, PC-12/45, and PC-12/47 airplanes are unique with respect to
other turbo-propeller designs in that the basic design does not include
a separate propeller control lever. Future use of these special
conditions on other turbo-propeller designs will require evaluation of
the engine and propeller control system to determine their
appropriateness.
Applicability
As discussed above, these special conditions are applicable to the
PC-12, PC-12/45, and PC-12/47 airplanes. Should Innovative Solutions &
Support, Ltd. apply at a later date for a supplemental type certificate
to modify any other model included on Type Certificate No. A78EU to
incorporate 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 PC-12, PC-12/45, and PC-12/47 airplanes. It is not a rule of general
applicability and affects only the applicant who applied to the FAA for
approval of these features on the airplane.
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, 44701-44702, 44704.
The Proposed Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes the
following special condition as part of the type certification basis for
Pilatus Aircraft Ltd., PC-12, PC-12/45, and PC-12/47 airplane models
modified by Innovative Solutions & Support, Inc.
1. Autothrust System
In addition to the requirements of Sec. Sec. 23.143, 23.1309, and
23.1329, the following apply:
(a) Quick disengagement controls for the autothrust function must
be provided for each pilot. The autothrust quick disengagement controls
must be located on the thrust control levers. Quick disengagement
controls must be readily accessible to each pilot while operating the
thrust control levers.
(b) The effects of a failure of the system to disengage the
autothrust function when manually commanded by the pilot must be
assessed in accordance with the requirements of Sec. 23.1309.
(c) Engagement or switching of the flight guidance system, a mode,
or a sensor may not cause the autothrust system to affect a transient
response that alters the airplane's flight path any greater than a
minor transient, as defined in paragraph (l)(1) of this special
condition.
(d) Under normal conditions, the disengagement of any automatic
control function of a flight guidance system may not cause a transient
response of the airplane's flight path any greater than a minor
transient.
(e) Under rare normal and non-normal conditions, disengagement of
any automatic control function of a flight guidance system may not
result in a transient any greater than a significant transient, as
defined in paragraph (l)(2) of this special condition.
(f) The function and direction of motion of each command reference
control, such as heading select or vertical speed, must be plainly
indicated on--or adjacent to--each control if necessary to prevent
inappropriate use or confusion.
(g) Under any condition of flight appropriate to its use, the
flight guidance system may not produce hazardous loads on the airplane,
nor create hazardous deviations in the flight path. This applies to
both fault-free operation and in the event of a malfunction, and
assumes that the pilot begins corrective action within a reasonable
time.
(h) When the flight guidance system is in use, a means must be
provided to avoid excursions beyond an acceptable margin from the speed
range of the normal flight envelope. If the airplane experiences an
excursion outside this range, a means must be provided to prevent the
flight guidance system from providing guidance or control to an unsafe
speed.
(i) The flight guidance system functions, controls, indications,
and alerts must be designed to minimize flightcrew errors and confusion
concerning the behavior and operation of the flight guidance system. A
means must be provided to indicate the current mode of operation,
including any armed modes, transitions, and reversions. Selector switch
position is not an acceptable means of indication. The controls and
indications must be grouped and presented in a logical and consistent
manner. The indications must be visible to each pilot under all
expected lighting conditions.
(j) Following disengagement of the autothrust function, a caution
(visual and auditory) must be provided to each pilot.
(k) During autothrust operation, it must be possible for the
flightcrew to move the thrust levers without requiring excessive force.
The autothrust may not create a potential hazard when the flightcrew
applies an override force to the thrust levers.
(l) For purposes of this section, a transient is a disturbance in
the control or flight path of the airplane that is not consistent with
response to flightcrew inputs or environmental conditions.
[[Page 17945]]
(1) A minor transient would not significantly reduce safety margins
and would involve flightcrew actions that are well within their
capabilities. A minor transient may involve a slight increase in
flightcrew workload or some physical discomfort to passengers or cabin
crew.
(2) A significant transient may lead to a significant reduction in
safety margins, an increase in flightcrew workload, discomfort to the
flightcrew, or physical distress to the passengers or cabin crew,
possibly including non-fatal injuries. Significant transients do not
require--in order to remain within or recover to the normal flight
envelope--any of the following:
(i) Exceptional piloting skill, alertness, or strength.
(ii) Forces applied by the pilot which are greater than those
specified in Sec. 23.143(c).
(iii) Accelerations or attitudes in the airplane that might result
in further hazard to secured or non-secured occupants.
Issued in Kansas City, Missouri on April 4, 2017.
Pat Mullen,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2017-07382 Filed 4-13-17; 8:45 am]
BILLING CODE 4910-13-P