Special Conditions: Pilatus Aircraft Ltd., PC-24, Autothrust System, 32618-32620 [2017-14938]

Download as PDF 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 Federal Register / Vol. 82, No. 135 / Monday, July 17, 2017 / Rules and Regulations 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 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: Autothrust System jstallworth on DSK7TPTVN1PROD with RULES 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 14:51 Jul 14, 2017 Jkt 241001 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: Discussion As discussed in the ‘‘Background’’ section, the PC–24 will incorporate an autothrust system, which is considered 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 the relevant portions 14 CFR 25.1329 (automatic pilot systems) applicable to the autothrust system— along with FAA experience with similar autothrust systems. This additional requirement mitigates the concerns associated with installation of the autothrust system. VerDate Sep<11>2014 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. 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. Autothrust System. For autothrust systems, in addition to the requirements of §§ 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 § 23.1309. (c) Engagement or switching of the flight guidance system, a mode or a sensor may not cause the auto thrust 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 ■ PO 00000 Frm 00007 Fmt 4700 Sfmt 4700 32619 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 period of 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. 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. (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 E:\FR\FM\17JYR1.SGM 17JYR1 32620 Federal Register / Vol. 82, No. 135 / Monday, July 17, 2017 / Rules and Regulations 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 § 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 July 6, 2017. Kelly Broadway, Acting Manager, Small Airplane Directorate Aircraft Certification Service. [FR Doc. 2017–14938 Filed 7–14–17; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2017–0696; Directorate Identifier 2017–NM–070–AD; Amendment 39–18960; AD 2017–14–16] RIN 2120–AA64 Airworthiness Directives; Bombardier, Inc., Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Final rule; request for comments. AGENCY: jstallworth on DSK7TPTVN1PROD with RULES Examining the AD Docket We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD–100–1A10 airplanes. This AD requires removing the fasteners attaching the machined center fitting to the rear spar frame lower flange splice, inspecting the fasteners and fastener holes for damage, reworking and repairing the fastener holes, as applicable, and replacing the fasteners. This AD was prompted by a report indicating that certain fasteners attaching the machined rear spar center fitting to the frame were installed with a gap between the fastener head and the structure, or were installed tilted. We are issuing this AD to address the unsafe condition on these products. DATES: This AD becomes effective August 1, 2017. SUMMARY: VerDate Sep<11>2014 14:51 Jul 14, 2017 Jkt 241001 The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of August 1, 2017. We must receive comments on this AD by August 31, 2017. ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments. • Fax: 202–493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590. • Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this final rule, contact Bombardier, Inc., ˆ 400 Cote-Vertu Road West, Dorval, ´ Quebec H4S 1Y9, Canada; telephone: 514–855–5000; fax: 514–855–7401; email: thd.crj@aero.bombardier.com; Internet: https://www.bombardier.com. You may view this referenced 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. It is also available on the Internet at https:// www.regulations.gov by searching for and locating Docket No. FAA–2017– 0696. You may examine the AD docket on the Internet at https:// www.regulations.gov by searching for and locating Docket No. FAA–2017– 0696; or in person at the Docket Operations office 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 street address for the Docket Operations office (telephone 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Aziz Ahmed, Airframe Engineer, Airframe and Mechanical Systems Branch, ANE– 171, FAA, New York Aircraft Certification Office (ACO), 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone: 516–228–7329; fax: 516–794–5531. PO 00000 Frm 00008 Fmt 4700 Sfmt 4700 SUPPLEMENTARY INFORMATION: Discussion Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian AD CF–2017–12, dated March 10, 2017 (referred to after this as the Mandatory Continuing Airworthiness Information, or ‘‘the MCAI’’), to correct an unsafe condition for certain Bombardier, Inc. Model BD–100–1A10 airplanes. The MCAI states: During production, it was observed that some fasteners joining the machined rear spar center fitting were installed with a gap between the fastener head and the structure, and others were installed tilted. Improperly installed fasteners could cause a premature failure of the fitting fasteners and cracking within the fitting or frame, resulting in the loss of structural integrity of the wing to fuselage attachment. This [Canadian] AD mandates the removal of all fasteners at the rear spar frame lower flange splice, inspection and rework [and repair] of the holes, and fastener replacement with self-aligning fasteners and self-aligning collars. The inspections include a general visual inspection of the fasteners for damage (i.e., missing, broken, or deformed), and an eddy current inspection of the fastener holes for damage. Rework includes deburring and chamfering the holes. You may examine the MCAI on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2017–0696. Related Service Information Under 1 CFR Part 51 Bombardier, Inc., has issued Service Bulletin 100–53–32, dated February 16, 2017. The service information describes procedures for removing and replacing the fasteners attaching the machined center fitting to the rear spar frame lower flange splice. The service information also describes procedures for inspecting the fasteners and fastener holes and reworking the fastener holes. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section. FAA’s Determination and Requirements of This AD This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this E:\FR\FM\17JYR1.SGM 17JYR1

Agencies

[Federal Register Volume 82, Number 135 (Monday, July 17, 2017)]
[Rules and Regulations]
[Pages 32618-32620]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-14938]


-----------------------------------------------------------------------

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

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 
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:
    [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 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.
23-272-SC.............................  Cirrus Design Corporation/Model
                                         SF50.
23-281-SC.............................  Innovative Solutions and Support
                                         Inc./Pilatus Aircraft Ltd., PC-
                                         12 Models.
------------------------------------------------------------------------

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.
---------------------------------------------------------------------------

    \2\ See https://rgl.faa.gov/ to review the listed special 
conditions.
---------------------------------------------------------------------------

    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 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, 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 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

[[Page 32619]]

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:

Autothrust System

Discussion

    As discussed in the ``Background'' section, the PC-24 will 
incorporate an autothrust system, which is considered 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 the relevant portions 14 CFR 25.1329 (automatic pilot systems) 
applicable to the autothrust system--along with FAA experience with 
similar autothrust systems. This additional requirement mitigates the 
concerns associated with installation of the autothrust system.

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. Autothrust System.
    For autothrust systems, 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 auto thrust 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 period of 
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. 
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.
    (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

[[Page 32620]]

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 July 6, 2017.
Kelly Broadway,
Acting Manager, Small Airplane Directorate Aircraft Certification 
Service.
[FR Doc. 2017-14938 Filed 7-14-17; 8:45 am]
BILLING CODE 4910-13-P
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.