Special Conditions: Bell Helicopter Textron, Inc. (BHTI), Model 525 Helicopters; Control Margin Awareness, 51624-51625 [2018-22265]
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Federal Register / Vol. 83, No. 198 / Friday, October 12, 2018 / Rules and Regulations
List of Subjects in 14 CFR Part 29
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for these
special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
khammond on DSK30JT082PROD with RULES
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 Bell Helicopter
Textron, Inc., Model 525 helicopters:
Flight Envelope Protection
The Flight Envelope Protection (FEP)
features of the flight control system
(FCS) must meet the following
requirements:
a. Onset characteristics of each
envelope protection feature must be
smooth, appropriate to the phase of
flight and type of maneuver, and not in
conflict with the ability of the pilot to
satisfactorily change rotorcraft flight
path, speed, or attitude within the
approved flight envelope.
b. Limit values of protected flight
parameters (and if applicable, associated
warning thresholds) must be compatible
with:
1. Rotorcraft structural limits;
2. Safe and controllable maneuvering
of the rotorcraft;
3. Margins to critical conditions.
Dynamic maneuvering, airframe and
system tolerances (both manufacturing
and in-service), and non-steady
atmospheric conditions—in any
appropriate combination and phase of
flight—must not result in a limited
flight parameter beyond the nominal
design limit value that would cause
unsafe flight characteristics;
4. Rotor rotational speed limits;
5. Blade stall limits; and
6. Engine and transmission torque
limits.
c. The aircraft must be responsive to
pilot-commanded dynamic
maneuvering within a suitable range of
the parameter limits that define the
approved flight envelope.
d. The FEP system must not create
unusual or adverse flight characteristics
when atmospheric conditions or
unintentional pilot action causes the
approved flight envelope to be
exceeded.
e. When simultaneous envelope
limiting is active, adverse coupling or
adverse priority must not result.
f. Following a single FEP failure
shown to not be extremely improbable,
the rotorcraft must:
1. Be capable of continued safe flight
and landing;
VerDate Sep<11>2014
16:22 Oct 11, 2018
Jkt 247001
2. Be capable of initial counteraction
of malfunctions without requiring
exceptional pilot skill or strength;
3. Be controllable and maneuverable
when operated with a degraded FCS,
within a practical flight envelope
identified in the Rotorcraft Flight
Manual;
4. Be capable of prolonged instrument
flight without requiring exceptional
pilot skill;
5. Meet the controllability and
maneuverability requirements of 14 CFR
part 29 Subpart B throughout a practical
flight envelope; and
6. Be safely controllable following any
additional failure or malfunction shown
to not be extremely improbable
occurring within the approved flight
envelope.
Issued in Fort Worth, Texas, on October 3,
2018.
Jorge Castillo,
Acting Manager, Rotorcraft Standards
Branch, Policy and Innovation Division,
Aircraft Certification Services.
[FR Doc. 2018–22267 Filed 10–11–18; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 29
[Docket No.FAA–2017–1128; Notice No. 29–
045–SC]
Special Conditions: Bell Helicopter
Textron, Inc. (BHTI), Model 525
Helicopters; Control Margin
Awareness
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions.
AGENCY:
These special conditions are
issued for the BHTI Model 525
helicopter. This helicopter will have a
novel or unusual design feature
associated with the fly-by-wire flight
control system (FBW FCS) in the area of
pilot awareness of the control margins
remaining while maneuvering the
helicopter. 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 November 13, 2018.
FOR FURTHER INFORMATION CONTACT:
George Harrum, Aerospace Engineer,
SUMMARY:
PO 00000
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Fmt 4700
Sfmt 4700
FAA, Rotorcraft Standards Branch,
Policy and Innovation Division, 10101
Hillwood Pkwy., Fort Worth, TX 76177;
telephone (817) 222–4087; email
George.Harrum@faa.gov.
SUPPLEMENTARY INFORMATION:
Background
On December 15, 2011, BHTI applied
for a type certificate for a new transport
category helicopter designated as the
Model 525. 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 BHTI 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
current 14 CFR part 29 regulations do
not contain adequate standards for FBW
FCS with respect to control margin
awareness. The airworthiness standards
for controllability and maneuverability
of the rotorcraft are contained in
§ 29.143. These controllability
requirements are compatible with most
FBW systems, while most of the
maneuverability requirements are not
affected by FBW systems, except for the
control margins. One of the purposes of
the rule is to ensure that control margins
(at the rotor and the anti-torque system
level) are sufficient in the defined flight
envelope to avoid loss of control (that is,
the rotorcraft has adequate control
power for the pilot to exit potentially
hazardous flight conditions). Implicit in
this purpose is that the pilot is provided
with sufficient awareness of proximity
to control limits. Because § 29.143 was
written to address hydro-mechanical
flight control systems, through which
pilot awareness of control margins is
provided by cyclic and pedal position
relative to cockpit control stops, the rule
is inadequate for certification of a FBW
FCS, where there is no mechanical link
between the inceptor and the receptor.
Without a constant correlation between
cockpit control and main or tail rotor
actuator positions, the FCS may not
provide tactile control margin feedback
to the pilot through cockpit control
position relative to the control position
physical stop or limit, for all flight
conditions. The special conditions will
require the minimum safety standard to
ensure awareness of proximity to
control limits at the main rotor and tail
rotor is provided to pilots of the Bell
Model 525 helicopter.
Type Certification Basis
Under the provisions of 14 CFR 21.17,
BHTI must show that the Model 525
helicopter meets the applicable
E:\FR\FM\12OCR1.SGM
12OCR1
Federal Register / Vol. 83, No. 198 / Friday, October 12, 2018 / Rules and Regulations
provisions of part 29, as amended by
Amendment 29–1 through 29–55
thereto. The BHTI Model 525
certification basis date is December 31,
2013, the effective date of application to
the FAA.
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 BHTI 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 BHTI Model 525
helicopter must comply with the noise
certification requirements of 14 CFR
part 36, and the FAA must issue a
finding of regulatory adequacy under
section 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 BHTI Model 525 helicopter
incorporates the following novel or
unusual design features: A four-axis full
authority digital FBW FCS. Pilot control
inputs, through the mechanically linked
cockpit controls (cyclic, collective,
directional pedals), are transmitted
electrically to each of the three Flight
Control Computers (FCCs). The pilot
control input signals are then processed
and transmitted to the hydraulic flight
control actuators which affect control of
the main and tail rotors.
khammond on DSK30JT082PROD with RULES
Discussion
These special conditions require the
minimum safety standard to ensure
awareness of proximity to control limits
at the main rotor and tail rotor is
provided to pilots of the Bell Model 525
helicopter. The system design must
provide the pilot with sufficient
awareness of proximity to control limits,
traditionally achieved through
conventional flight controls by the
pilot’s inherent awareness of cyclic stick
and pedal position relative to control
stops.
VerDate Sep<11>2014
16:22 Oct 11, 2018
Jkt 247001
Discussion of Comments
Notice of proposed special conditions
No. 29–045–SC for the BHTI Model 525
helicopter was published in the Federal
Register on June 6, 2018 (83 FR 26225).
No comments were received, and the
special conditions are adopted as
proposed.
Applicability
As discussed above, these special
conditions are applicable to the BHTI
Model 525 helicopter. Should BHTI
apply at a later date for a change to the
type certificate to include another
model incorporating the same novel or
unusual design feature, the special
conditions would apply to that model as
well.
Conclusion
This action affects only certain novel
or unusual design features on one model
of rotorcraft. It is not a rule of general
applicability.
List of Subjects in 14 CFR Part 29
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for these
special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
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 Bell Helicopter
Textron, Inc., Model 525 helicopters:
Control Margin Awareness
In addition to the existing § 29.143
requirements, the following special
condition applies: The system design
must ensure that the flight crew is made
suitably aware whenever the means of
primary flight control approaches the
limits of control authority. For the
context of this special condition, the
term ‘‘suitable’’ indicates an appropriate
balance between nuisance and
necessary operation.
Issued in Ft Worth, Texas, on October 3,
2018.
Jorge Castillo,
Acting Manager, Rotorcraft Standards
Branch, Policy and Innovation Division,
Aircraft Certification Service.
[FR Doc. 2018–22265 Filed 10–11–18; 8:45 am]
BILLING CODE 4910–13–P
PO 00000
Frm 00003
Fmt 4700
Sfmt 4700
51625
DEPARTMENT OF HOMELAND
SECURITY
Coast Guard
33 CFR Part 100
[Docket Number USCG–2018–0577]
RIN 1625–AA08
Special Local Regulation; Choptank
River, Talbot and Dorchester Counties,
MD
Coast Guard, DHS.
Temporary final rule.
AGENCY:
ACTION:
The Coast Guard is
establishing temporary special local
regulations for certain navigable waters
of the Choptank River. This action is
necessary to provide for the safety of life
on these waters near Oxford, MD, from
October 7, 2018, through October 15,
2018, during a sailboat regatta. This
regulation prohibits persons and vessels
from being in the regulated area unless
authorized by the Captain of the Port
Maryland-National Capital Region or a
designated representative.
DATES: This rule is effective without
actual notice from October 12, 2018
through 5:30 p.m. on October 15, 2018.
For the purposes of enforcement, actual
notice will be used from 11:30 a.m. on
October 7, 2018 until October 12, 2018.
ADDRESSES: To view documents
mentioned in this preamble as being
available in the docket, go to https://
www.regulations.gov, type USCG–2018–
0577 in the ‘‘SEARCH’’ box and click
‘‘SEARCH.’’ Click on Open Docket
Folder on the line associated with this
rule.
FOR FURTHER INFORMATION CONTACT: If
you have questions on this rule, call or
email Mr. Ronald Houck, U.S. Coast
Guard Sector Maryland-National Capital
Region; telephone 410–576–2674, email
Ronald.L.Houck@uscg.mil.
SUPPLEMENTARY INFORMATION:
SUMMARY:
I. Table of Abbreviations
CFR Code of Federal Regulations
COTP Captain of the Port
DHS Department of Homeland Security
FR Federal Register
NPRM Notice of proposed rulemaking
§ Section
U.S.C. United States Code
II. Background Information and
Regulatory History
On February 13, 2018, the Tred Avon
Yacht Club of Oxford, MD, notified the
Coast Guard through submission of a
marine event application that from
October 5, 2018, through October 15,
2018, it will be conducting a sailboat
E:\FR\FM\12OCR1.SGM
12OCR1
]]>Agencies
[Federal Register Volume 83, Number 198 (Friday, October 12, 2018)]
[Rules and Regulations]
[Pages 51624-51625]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-22265]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 29
[Docket No.FAA-2017-1128; Notice No. 29-045-SC]
Special Conditions: Bell Helicopter Textron, Inc. (BHTI), Model
525 Helicopters; Control Margin Awareness
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the BHTI Model 525
helicopter. This helicopter will have a novel or unusual design feature
associated with the fly-by-wire flight control system (FBW FCS) in the
area of pilot awareness of the control margins remaining while
maneuvering the helicopter. 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 November 13, 2018.
FOR FURTHER INFORMATION CONTACT: George Harrum, Aerospace Engineer,
FAA, Rotorcraft Standards Branch, Policy and Innovation Division, 10101
Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-4087; email
[email protected].
SUPPLEMENTARY INFORMATION:
Background
On December 15, 2011, BHTI applied for a type certificate for a new
transport category helicopter designated as the Model 525. 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 BHTI 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 current 14
CFR part 29 regulations do not contain adequate standards for FBW FCS
with respect to control margin awareness. The airworthiness standards
for controllability and maneuverability of the rotorcraft are contained
in Sec. 29.143. These controllability requirements are compatible with
most FBW systems, while most of the maneuverability requirements are
not affected by FBW systems, except for the control margins. One of the
purposes of the rule is to ensure that control margins (at the rotor
and the anti-torque system level) are sufficient in the defined flight
envelope to avoid loss of control (that is, the rotorcraft has adequate
control power for the pilot to exit potentially hazardous flight
conditions). Implicit in this purpose is that the pilot is provided
with sufficient awareness of proximity to control limits. Because Sec.
29.143 was written to address hydro-mechanical flight control systems,
through which pilot awareness of control margins is provided by cyclic
and pedal position relative to cockpit control stops, the rule is
inadequate for certification of a FBW FCS, where there is no mechanical
link between the inceptor and the receptor. Without a constant
correlation between cockpit control and main or tail rotor actuator
positions, the FCS may not provide tactile control margin feedback to
the pilot through cockpit control position relative to the control
position physical stop or limit, for all flight conditions. The special
conditions will require the minimum safety standard to ensure awareness
of proximity to control limits at the main rotor and tail rotor is
provided to pilots of the Bell Model 525 helicopter.
Type Certification Basis
Under the provisions of 14 CFR 21.17, BHTI must show that the Model
525 helicopter meets the applicable
[[Page 51625]]
provisions of part 29, as amended by Amendment 29-1 through 29-55
thereto. The BHTI Model 525 certification basis date is December 31,
2013, the effective date of application to the FAA.
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 BHTI 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 BHTI Model 525 helicopter must comply with the noise
certification requirements of 14 CFR part 36, and the FAA must issue a
finding of regulatory adequacy under section 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 BHTI Model 525 helicopter incorporates the following novel or
unusual design features: A four-axis full authority digital FBW FCS.
Pilot control inputs, through the mechanically linked cockpit controls
(cyclic, collective, directional pedals), are transmitted electrically
to each of the three Flight Control Computers (FCCs). The pilot control
input signals are then processed and transmitted to the hydraulic
flight control actuators which affect control of the main and tail
rotors.
Discussion
These special conditions require the minimum safety standard to
ensure awareness of proximity to control limits at the main rotor and
tail rotor is provided to pilots of the Bell Model 525 helicopter. The
system design must provide the pilot with sufficient awareness of
proximity to control limits, traditionally achieved through
conventional flight controls by the pilot's inherent awareness of
cyclic stick and pedal position relative to control stops.
Discussion of Comments
Notice of proposed special conditions No. 29-045-SC for the BHTI
Model 525 helicopter was published in the Federal Register on June 6,
2018 (83 FR 26225). No comments were received, and the special
conditions are adopted as proposed.
Applicability
As discussed above, these special conditions are applicable to the
BHTI Model 525 helicopter. Should BHTI apply at a later date for a
change to the type certificate to include another model incorporating
the same novel or unusual design feature, the special conditions would
apply to that model as well.
Conclusion
This action affects only certain novel or unusual design features
on one model of rotorcraft. It is not a rule of general applicability.
List of Subjects in 14 CFR Part 29
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
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 Bell Helicopter Textron, Inc., Model
525 helicopters:
Control Margin Awareness
In addition to the existing Sec. 29.143 requirements, the
following special condition applies: The system design must ensure that
the flight crew is made suitably aware whenever the means of primary
flight control approaches the limits of control authority. For the
context of this special condition, the term ``suitable'' indicates an
appropriate balance between nuisance and necessary operation.
Issued in Ft Worth, Texas, on October 3, 2018.
Jorge Castillo,
Acting Manager, Rotorcraft Standards Branch, Policy and Innovation
Division, Aircraft Certification Service.
[FR Doc. 2018-22265 Filed 10-11-18; 8:45 am]
BILLING CODE 4910-13-P
