Special Conditions: Bell Textron Inc., Model 525 Helicopter; Fly-By-Wire (FBW) Flight Control System (FCS), 7516-7518 [2021-01958]

Download as PDF 7516 Federal Register / Vol. 86, No. 18 / Friday, January 29, 2021 / Proposed Rules The NRC may post additional materials related to this rulemaking activity to the Federal rulemaking website at www.regulations.gov under Docket ID NRC–2009–0196. These documents will inform the public of the current status of this activity and/or provide additional material for use at future public meetings. The Federal rulemaking website allows you to receive alerts when changes or additions occur in a docket folder. To subscribe: (1) Navigate to the docket folder (NRC–2009–0196); (2) click the ‘‘Sign up for Email Alerts’’ link; and (3) enter your email address and select how frequently you would like to receive emails (daily, weekly, or monthly). Dated: January 19, 2021. For the Nuclear Regulatory Commission. John R. Tappert, Director, Division of Rulemaking, Environmental and Financial Support, Office of Nuclear Material Safety and Safeguards. [FR Doc. 2021–01860 Filed 1–28–21; 8:45 am] BILLING CODE 7590–01–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 29 [Docket No. FAA–2021–0065; Notice No. 29– 054–SC] Special Conditions: Bell Textron Inc., Model 525 Helicopter; Fly-By-Wire (FBW) Flight Control System (FCS) Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed special conditions. AGENCY: This action proposes special conditions for the Bell Textron Inc. (Bell) Model 525 helicopter. This helicopter will have a novel or unusual design feature associated with a fly-bywire (FBW) flight control system (FCS). 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 comments on or before March 15, 2021. ADDRESSES: Send comments identified by Docket No. FAA–2021–0065 using any of the following methods: • Federal eRegulations Portal: Go to https://www.regulations.gov/ and follow khammond on DSKJM1Z7X2PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 16:44 Jan 28, 2021 Jkt 253001 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 or 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: Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments it receives, without change, to https:// www.regulations.gov/, including any personal information the commenter provides. Using the search function of the docket website, 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). Confidential Business Information: CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to these proposed special conditions contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to these proposed special conditions, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ‘‘PROPIN.’’ The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of these proposed special conditions. Submissions containing CBI should be sent to John VanHoudt, FAA, Dynamic Systems Section, AIR–627, Technical Innovation Policy Branch, Policy and Innovation Division, Aircraft Certification Service, 10101 Hillwood Parkway, Fort Worth, TX 76177–98198; telephone and fax 817–222–5193; email John.G.Van.Houdt@FAA.Gov. Any commentary that the FAA receives which is not specifically designated as PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 CBI will be placed in the public docket for this rulemaking. 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 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: John VanHoudt, FAA, Dynamic Systems Section, AIR–627, Technical Innovation Policy Branch, Policy and Innovation Division, Aircraft Certification Service, 10101 Hillwood Parkway, Fort Worth, TX 76177–98198; telephone and fax 817–222–5193; email John.G.Van.Houdt@FAA.Gov. SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA–2021–0065; Notice No. 29–054– SC’’ at the beginning of your comments. The most helpful comments reference a specific portion of the special conditions, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend these proposed special conditions because of those comments. Background On December 15, 2011, Bell applied for a type certificate for a new 14 CFR part 29 transport category helicopter designated as the Model 525. Bell applied for multiple extensions, with the most recent occurring on November 12, 2020. The date of the updated type certification basis is December 31, 2016, based upon the applicant’s proposed type certificate issuance date of December 31, 2021. The Model 525 is a medium twin-engine rotorcraft. The design maximum takeoff weight is 20,500 pounds, with a maximum capacity of 19 passengers and a crew of 2. The Bell Model 525 helicopter will be equipped with a four axis full authority digital FBW FCS that provides for aircraft control through pilot input and coupled flight director modes. The design of the Bell Model 525 FBW controls, which provides no direct hydro-mechanical linkage between the primary cockpit flight controls or inceptors and the main and tail rotor E:\FR\FM\29JAP1.SGM 29JAP1 khammond on DSKJM1Z7X2PROD with PROPOSALS Federal Register / Vol. 86, No. 18 / Friday, January 29, 2021 / Proposed Rules actuators, is a first for commercial rotorcraft use. Therefore, the regulations do not contain adequate or appropriate safety standards for this new design feature. The rotorcraft industry is producing new generations of helicopters, and gradually increasing size, speed, load capacity, and technical sophistication. In recent years, an accelerated trend has occurred using rotorcraft for a wide range of commercial and industrial applications. This has resulted in increased complexity of modern control systems and increased use of automation in flight control systems, including the implementation of advanced flight control systems such as FBW FCS. Title 14, Code of Federal Regulations (CFR), § 29.671(c), which provides requirements for transport category rotorcraft control systems, does not contain adequate or appropriate safety standards for this new design feature. 14 CFR 29.671(c) requires, in part, a means to allow the pilot to determine that full control authority is available prior to flight. This command control authority is typically achieved by verifying movement of the control quadrant through an unassisted mechanical pilotinitiated manipulation of the primary flight controls prior to flight. Although this approach does not guarantee that 100% maximum control movement of the flight controls has been achieved prior to flight, it has been deemed appropriate for mechanical flight control systems. Unlike traditional mechanical flight control systems, the FBW FCS reduces the opportunity for jamming of the flight controls due to mechanical bind, improper servo adjustment resulting from faulty maintenance, or presence of a foreign object in the control mechanism that will impair safety. This reduced exposure for jams is due to the replacement of the mechanical linkages between the primary cockpit flight controls or inceptors and the main and tail rotor actuators with digital signal processing wiring. However, the FBW FCS does increase the potential for latent failures or faults that could impair full control authority, unless a means exists to ensure the FBW FCS is fully functional and free of control authority impairment prior to flight. A FBW system may have the ability to verify full control authority without having to move the primary flight controls. Although part 29 does not contain adequate or appropriate safety standards for this novel or unusual design feature, 14 CFR 25.671, amendment 25–23, provides these requirements for transport category airplanes. VerDate Sep<11>2014 16:44 Jan 28, 2021 Jkt 253001 Accordingly, these proposed special conditions are based on § 25.671 to provide requirements for a FBW FCS on the Bell Model 525 helicopter. 14 CFR 25.671(c) provides the same level of safety as that intended by § 29.671(c) when employing a FBW FCS by including requirements for jamming and failure analysis. The proposed special conditions would require a comprehensive safety analysis of the aircraft’s FBW FCS to include failures due to command logic (software), mechanical and electronic interfaces to other systems, jamming and maintenance. Therefore, in conjunction with § 29.671(a) and (b), the proposed special conditions incorporate provisions from § 25.671(c) to establish a level of safety equivalent to that established in the regulations. Type Certification Basis Under the provisions of 14 CFR 21.17, Bell must show that the Model 525 helicopter meets the applicable provisions of part 29, as amended by Amendments 29 through 55 thereto. The Bell Model 525 certification basis date is December 31, 2016. If the Administrator finds that the applicable airworthiness regulations (i.e., 14 CFR part 29) do not contain adequate or appropriate safety standards for the Bell Model 525 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 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 the applicable airworthiness regulations and special conditions, the Bell Model 525 helicopter must comply with the the noise certification requirements of 14 CFR part 36, and the FAA must issue a finding of regulatory adequacy under § 611 of Public Law 92–574, the ‘‘Noise Control Act of 1972.’’. 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). Novel or Unusual Design Features The Bell Model 525 helicopter will incorporate the following novel or unusual design features: A FBW FCS. This new design feature has no direct hydro-mechanical linkage between the primary cockpit flight controls or PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 7517 inceptors and the main and tail rotor actuators, thereby eliminating the more complex elements of either a manual movement of the controls by the pilot, or another manual means. Discussion The proposed special conditions would require that a means be available to show full control authority for all powered control systems. The 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. Applicability As discussed above, these special conditions are applicable to the Bell Model 525 helicopter. Should Bell apply at a later date for a change to the type certificate to include aother model incorporating the same novel or unusual design feature, these special conditions would apply to that model as well. Conclusion This action affects only a certain novel or unusual design feature on the Bell Model 525 helicopter. It is not a rule of general applicability. List of Subjects in 14 CFR Part 29 Aircraft, Aviation safety, Reporting and recordkeeping requirements. Authority 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 conditions in lieu of § 29.671(c) as part of the type certification basis for the Bell Textron Inc. Model 525 helicopter: The rotorcraft must be shown by analysis, tests, or both, to be capable of continued safe flight and landing after any of the following failures or jamming in the flight control system within the normal flight envelope, without requiring exceptional piloting skill or strength. Probable failures must have only minor effects. (1) Any single failure not shown to be extremely improbable, excluding jamming. (2) Any combination of failures not shown to be extremely improbable, excluding jamming. (3) Any jam in a control position normally encountered during hover, takeoff, climb, cruise, normal turns, E:\FR\FM\29JAP1.SGM 29JAP1 7518 Federal Register / Vol. 86, No. 18 / Friday, January 29, 2021 / Proposed Rules descent, and landing, unless the jam is shown to be extremely improbable or can be alleviated. Issued in Fort Worth, Texas. Jorge Castillo, Manager, Strategic Policy Rotorcraft Section, Policy and Innovation Division, Aircraft Certification Service. [FR Doc. 2021–01958 Filed 1–28–21; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF ENERGY Federal Energy Regulatory Commission 18 CFR Part 39 [Docket No. RM21–12–000] Revisions to Regulations on Electric Reliability Organization Performance Assessments Federal Energy Regulatory Commission, Department of Energy. ACTION: Notice of proposed rulemaking. AGENCY: The Federal Energy Regulatory Commission (Commission) proposes to amend the Commission’s regulations to require the Commissioncertified Electric Reliability Organization to submit assessments of its performance every three years instead of the current period of every five years. The Commission also proposes to add to the Commission’s regulations a requirement for the Electric Reliability Organization to include in its performance assessment a detailed discussion of any areas of the Electric Reliability Organization’s responsibilities and activities, or a Regional Entity’s delegated functions, beyond those required by the Commission’s regulations, that the Commission has identified at least 90 days prior to the expected performance assessment submission date. Finally, the Commission proposes formalizing the method for the Electric Reliability Organization and Regional Entities to receive and respond to recommendations by the users, owners, and operators of the Bulk-Power System, and other interested parties for improvement of the Electric Reliability Organization’s operations, activities, oversight and procedures. DATES: Comments are due March 1, 2021. ADDRESSES: Comments, identified by docket number, may be filed electronically at https://www.ferc.gov in acceptable native applications and print-to-PDF, but not in scanned or picture format. For those unable to file khammond on DSKJM1Z7X2PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 16:44 Jan 28, 2021 Jkt 253001 electronically, comments may be filed by mail to: Federal Energy Regulatory Commission, Secretary of the Commission, 888 First Street NE, Washington, DC 20426. Hand-delivered comments must be delivered to: Federal Energy Regulatory Commission, 12225 Wilkins Avenue, Rockville, Maryland 20852. The Comment Procedures Section of this document contains more detailed filing procedures. FOR FURTHER INFORMATION CONTACT: Leigh Anne Faugust (Legal Information), Office of the General Counsel, Federal Energy Regulatory Commission, 888 First Street NE, Washington, DC 20426, Telephone: (202) 502–6396. SUPPLEMENTARY INFORMATION: 1. Pursuant to section 215 of the Federal Power Act (FPA),1 the Commission proposes to amend § 39.3(c) of the Commission’s regulations to require the Commissioncertified Electric Reliability Organization (ERO) to submit assessments of its performance every three years instead of the current period of every five years.2 We believe that the proposed amendment will provide better continuity in our review of the ERO’s operations, activities, oversight, procedures, and evaluation of the effectiveness of each Regional Entity in the performance of delegated functions. We also believe the proposed shorter performance assessment cycle will provide an opportunity to identify potential improvements with regards to ERO performance in a more timely fashion, allow for changes to be made in a more timely manner, and improve the efficiency of the overall performance assessment process. 2. Also, pursuant to section 215 of the FPA, we propose to add paragraph (iv) to § 39.3(c)(1) of the Commission’s regulations to require the Commissioncertified ERO to include in its performance assessments a detailed discussion of any areas of the ERO’s responsibilities and activities, or the Regional Entities’ delegated functions, beyond those required by § 39.3(c)(1)(i), (ii), and (iii), that the Commission identifies for inclusion at least 90 days prior to the expected performance assessment submission date. 3. Finally, we propose to amend § 39.3(c)(1)(ii) of the Commission’s regulations to require the ERO to solicit via a formal public comment period recommendations by the users, owners, and operators of the Bulk-Power System, and other interested parties for improvement of the ERO’s operations, activities, oversight and procedures. 1 16 2 18 PO 00000 U.S.C. 824o. CFR 39.3(c). Frm 00006 Fmt 4702 Sfmt 4702 I. Background A. Section 215 of the FPA 4. Section 215 of the FPA requires the Commission to issue regulations that, among other things, provide for the certification of an entity as the ERO if it meets certain criteria.3 Specifically, FPA section 215(c) establishes that an ERO candidate must have the ability to develop and enforce mandatory Reliability Standards that provide for an adequate level of reliability of the BulkPower System.4 The statute also requires that an ERO candidate have established rules that: (1) Assure independence, while assuring fair stakeholder representation and balanced decision-making; (2) equitably allocate reasonable dues, fees, and other charges; (3) provide fair and impartial procedures for enforcing Reliability Standards through imposition of penalties; (4) provide reasonable notice and opportunity for public comment, due process, and balance in developing Reliability Standards and otherwise exercising its duties; and (5) provide appropriate steps to gain recognition in Canada and Mexico. 5. FPA section 215(e)(4) provides that the ERO may delegate authority to a Regional Entity for the purpose of proposing regional Reliability Standards and enforcing Reliability Standards. Regional Entities must meet the same statutory criteria as those required for Commission certification of an ERO, except that more flexibility is allowed in the composition of a Regional Entity board of directors. The Commission must approve a delegation agreement between the ERO and a Regional Entity, and the Commission is authorized to modify such delegation. B. Order No. 672 6. On February 3, 2006, the Commission issued Order No. 672, which amended the Commission’s regulations to implement the requirements of FPA section 215.5 In Order No. 672, the Commission 3 16 U.S.C. 824o; (on July 20, 2006, the Commission certified NERC as the ERO for the continental United States under FPA section 215(c)). North American Electric Reliability Corp., 116 FERC ¶ 61,062, order on reh’g and compliance, 117 FERC ¶ 61,126 (2006), order on compliance, 118 FERC ¶ 61,030, order on compliance, 118 FERC ¶ 61,190, order on reh’g, 119 FERC ¶ 61,046 (2007), aff’d sub nom. Alcoa Inc. v. FERC, 564 F.3d 1342 (D.C. Cir. 2009). 4 Id. section 824o(c). 5 Rules Concerning Certification of the Electric Reliability Organization; and Procedures for the Establishment, Approval, and Enforcement of Electric Reliability Standards, Order No. 672, 71 FR 8662 (Feb. 17, 2006), 114 FERC ¶ 61,104, at P 186, order on reh’g, Order No. 672–A, 114 FERC ¶ 61,328 (2006). E:\FR\FM\29JAP1.SGM 29JAP1

Agencies

[Federal Register Volume 86, Number 18 (Friday, January 29, 2021)]
[Proposed Rules]
[Pages 7516-7518]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-01958]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 29

[Docket No. FAA-2021-0065; Notice No. 29-054-SC]


Special Conditions: Bell Textron Inc., Model 525 Helicopter; Fly-
By-Wire (FBW) Flight Control System (FCS)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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

SUMMARY: This action proposes special conditions for the Bell Textron 
Inc. (Bell) Model 525 helicopter. This helicopter will have a novel or 
unusual design feature associated with a fly-by-wire (FBW) flight 
control system (FCS). 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 comments on or before March 15, 2021.

ADDRESSES: Send comments identified by Docket No. FAA-2021-0065 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 or 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: Except for Confidential Business Information (CBI) as 
described in the following paragraph, and other information as 
described in 14 CFR 11.35, the FAA will post all comments it receives, 
without change, to https://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket website, 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).
    Confidential Business Information: CBI is commercial or financial 
information that is both customarily and actually treated as private by 
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), 
CBI is exempt from public disclosure. If your comments responsive to 
these proposed special conditions contain commercial or financial 
information that is customarily treated as private, that you actually 
treat as private, and that is relevant or responsive to these proposed 
special conditions, it is important that you clearly designate the 
submitted comments as CBI. Please mark each page of your submission 
containing CBI as ``PROPIN.'' The FAA will treat such marked 
submissions as confidential under the FOIA, and they will not be placed 
in the public docket of these proposed special conditions. Submissions 
containing CBI should be sent to John VanHoudt, FAA, Dynamic Systems 
Section, AIR-627, Technical Innovation Policy Branch, Policy and 
Innovation Division, Aircraft Certification Service, 10101 Hillwood 
Parkway, Fort Worth, TX 76177-98198; telephone and fax 817-222-5193; 
email [email protected]. Any commentary that the FAA receives 
which is not specifically designated as CBI will be placed in the 
public docket for this rulemaking.
    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 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: John VanHoudt, FAA, Dynamic Systems 
Section, AIR-627, Technical Innovation Policy Branch, Policy and 
Innovation Division, Aircraft Certification Service, 10101 Hillwood 
Parkway, Fort Worth, TX 76177-98198; telephone and fax 817-222-5193; 
email [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-0065; Notice No. 29-054-
SC'' at the beginning of your comments. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
these proposed special conditions because of those comments.

Background

    On December 15, 2011, Bell applied for a type certificate for a new 
14 CFR part 29 transport category helicopter designated as the Model 
525. Bell applied for multiple extensions, with the most recent 
occurring on November 12, 2020. The date of the updated type 
certification basis is December 31, 2016, based upon the applicant's 
proposed type certificate issuance date of December 31, 2021. The Model 
525 is a medium twin-engine rotorcraft. The design maximum takeoff 
weight is 20,500 pounds, with a maximum capacity of 19 passengers and a 
crew of 2.
    The Bell Model 525 helicopter will be equipped with a four axis 
full authority digital FBW FCS that provides for aircraft control 
through pilot input and coupled flight director modes. The design of 
the Bell Model 525 FBW controls, which provides no direct hydro-
mechanical linkage between the primary cockpit flight controls or 
inceptors and the main and tail rotor

[[Page 7517]]

actuators, is a first for commercial rotorcraft use. Therefore, the 
regulations do not contain adequate or appropriate safety standards for 
this new design feature.
    The rotorcraft industry is producing new generations of 
helicopters, and gradually increasing size, speed, load capacity, and 
technical sophistication. In recent years, an accelerated trend has 
occurred using rotorcraft for a wide range of commercial and industrial 
applications. This has resulted in increased complexity of modern 
control systems and increased use of automation in flight control 
systems, including the implementation of advanced flight control 
systems such as FBW FCS.
    Title 14, Code of Federal Regulations (CFR), Sec.  29.671(c), which 
provides requirements for transport category rotorcraft control 
systems, does not contain adequate or appropriate safety standards for 
this new design feature. 14 CFR 29.671(c) requires, in part, a means to 
allow the pilot to determine that full control authority is available 
prior to flight. This command control authority is typically achieved 
by verifying movement of the control quadrant through an unassisted 
mechanical pilot-initiated manipulation of the primary flight controls 
prior to flight. Although this approach does not guarantee that 100% 
maximum control movement of the flight controls has been achieved prior 
to flight, it has been deemed appropriate for mechanical flight control 
systems.
    Unlike traditional mechanical flight control systems, the FBW FCS 
reduces the opportunity for jamming of the flight controls due to 
mechanical bind, improper servo adjustment resulting from faulty 
maintenance, or presence of a foreign object in the control mechanism 
that will impair safety. This reduced exposure for jams is due to the 
replacement of the mechanical linkages between the primary cockpit 
flight controls or inceptors and the main and tail rotor actuators with 
digital signal processing wiring. However, the FBW FCS does increase 
the potential for latent failures or faults that could impair full 
control authority, unless a means exists to ensure the FBW FCS is fully 
functional and free of control authority impairment prior to flight. A 
FBW system may have the ability to verify full control authority 
without having to move the primary flight controls.
    Although part 29 does not contain adequate or appropriate safety 
standards for this novel or unusual design feature, 14 CFR 25.671, 
amendment 25-23, provides these requirements for transport category 
airplanes. Accordingly, these proposed special conditions are based on 
Sec.  25.671 to provide requirements for a FBW FCS on the Bell Model 
525 helicopter. 14 CFR 25.671(c) provides the same level of safety as 
that intended by Sec.  29.671(c) when employing a FBW FCS by including 
requirements for jamming and failure analysis. The proposed special 
conditions would require a comprehensive safety analysis of the 
aircraft's FBW FCS to include failures due to command logic (software), 
mechanical and electronic interfaces to other systems, jamming and 
maintenance. Therefore, in conjunction with Sec.  29.671(a) and (b), 
the proposed special conditions incorporate provisions from Sec.  
25.671(c) to establish a level of safety equivalent to that established 
in the regulations.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Bell must show that the Model 
525 helicopter meets the applicable provisions of part 29, as amended 
by Amendments 29 through 55 thereto. The Bell Model 525 certification 
basis date is December 31, 2016.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 29) do not contain adequate or 
appropriate safety standards for the Bell Model 525 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 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 the applicable airworthiness regulations and special 
conditions, the Bell Model 525 helicopter must comply with the the 
noise certification requirements of 14 CFR part 36, and the FAA must 
issue a finding of regulatory adequacy under Sec.  611 of Public Law 
92-574, the ``Noise Control Act of 1972.''.
    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 Bell Model 525 helicopter will incorporate the following novel 
or unusual design features: A FBW FCS.
    This new design feature has no direct hydro-mechanical linkage 
between the primary cockpit flight controls or inceptors and the main 
and tail rotor actuators, thereby eliminating the more complex elements 
of either a manual movement of the controls by the pilot, or another 
manual means.

Discussion

    The proposed special conditions would require that a means be 
available to show full control authority for all powered control 
systems.
    The 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.

Applicability

    As discussed above, these special conditions are applicable to the 
Bell Model 525 helicopter. Should Bell apply at a later date for a 
change to the type certificate to include aother model incorporating 
the same novel or unusual design feature, these special conditions 
would apply to that model as well.

Conclusion

    This action affects only a certain novel or unusual design feature 
on the Bell Model 525 helicopter. It is not a rule of general 
applicability.

List of Subjects in 14 CFR Part 29

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

Authority 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 conditions in lieu of Sec.  29.671(c) as part of the 
type certification basis for the Bell Textron Inc. Model 525 
helicopter:
    The rotorcraft must be shown by analysis, tests, or both, to be 
capable of continued safe flight and landing after any of the following 
failures or jamming in the flight control system within the normal 
flight envelope, without requiring exceptional piloting skill or 
strength. Probable failures must have only minor effects.
    (1) Any single failure not shown to be extremely improbable, 
excluding jamming.
    (2) Any combination of failures not shown to be extremely 
improbable, excluding jamming.
    (3) Any jam in a control position normally encountered during 
hover, takeoff, climb, cruise, normal turns,

[[Page 7518]]

descent, and landing, unless the jam is shown to be extremely 
improbable or can be alleviated.

    Issued in Fort Worth, Texas.
Jorge Castillo,
Manager, Strategic Policy Rotorcraft Section, Policy and Innovation 
Division, Aircraft Certification Service.
[FR Doc. 2021-01958 Filed 1-28-21; 8:45 am]
BILLING CODE 4910-13-P
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