Special Conditions: Bombardier Inc., Model BD-700-2A12 and BD-700-2A13 Series Airplanes, Electronic Flight Control System: Lateral-Directional and Longitudinal Stability, and Low-Energy Awareness, 14126-14128 [2017-05327]
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14126
Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Rules and Regulations
interfaced with a diverse set of
functions, including:
• Flight-safety-related control,
communication, and navigation systems
(airplane-control domain);
• Operator business and
administrative support (operatorinformation domain); and
• Passenger information and
entertainment systems (passengerentertainment domain).
Discussion
The Textron Model 700 airplane
allows connection to airplane electronic
systems and networks, and access from
airplane external sources (e.g., operator
networks, wireless devices, Internet
connectivity, service-provider satellite
communications, electronic flight bags,
etc.) to the airplane’s previously
isolated, internal, electronic
components. These airplane internal
electronic components include
electronic equipment and systems,
instruments, networks, servers, software
and electronic components, fieldloadable software and hardware
applications, and databases. This
proposed design may otherwise result in
network security vulnerabilities, if not
appropriately protected, from
intentional or unintentional corruption
of data and systems required for the
safety, operation, and maintenance of
the airplane. The existing regulations
and guidance material did not anticipate
this type of system architecture, nor
external wired and wireless electronic
access to airplane electronic systems.
Furthermore, regulations, and current
system safety-assessment policy and
techniques, do not address potential
security vulnerabilities that could be
caused by unauthorized access to
airplane electronic systems and
networks.
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.
mstockstill on DSK3G9T082PROD with RULES
Applicability
As discussed above, these special
conditions are applicable to the Textron
Model 700 airplane. Should Textron
apply at a later date for a change to the
type certificate to include another
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 one
VerDate Sep<11>2014
19:31 Mar 16, 2017
Jkt 241001
model of airplane. It is not a rule of
general applicability.
The substance of these special
conditions has been subjected to the
notice and comment period in several
prior instances 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, because a
delay would significantly affect the
certification of the airplane, the FAA
has determined that prior public notice
and comment are unnecessary and
impracticable, and good cause exists for
adopting these special conditions upon
publication in the Federal Register. 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 25
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 Textron Model
700 airplanes.
1. The applicant must ensure that the
airplane electronic systems are protected
from access by unauthorized sources external
to the airplane, including those possibly
caused by maintenance activity.
2. The applicant must ensure that
electronic system-security threats are
identified and assessed, and that effective
electronic system-security protection
strategies are implemented to protect the
airplane from all adverse impacts on safety,
functionality, and continued airworthiness.
3. The applicant must establish appropriate
procedures to allow the operator to ensure
that continued airworthiness of the airplane
is maintained, including all post-typecertification modifications that may have an
impact on the approved electronic systemsecurity safeguards.
Issued in Renton, Washington, on February
10, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 2017–05332 Filed 3–16–17; 8:45 am]
BILLING CODE 4910–13–P
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2016–9296; Special
Conditions No. 25–647–SC]
Special Conditions: Bombardier Inc.,
Model BD–700–2A12 and BD–700–
2A13 Series Airplanes, Electronic
Flight Control System: LateralDirectional and Longitudinal Stability,
and Low-Energy Awareness
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Bombardier Inc.
(Bombardier) Model BD–700–2A12 and
BD–700–2A13 series airplanes. These
airplanes will have a novel or unusual
design feature when compared to the
state of technology envisioned in the
airworthiness standards for transportcategory airplanes. This design feature
is lateral-directional and longitudinal
stability, and low-energy awareness,
provided through an electronic flightcontrol system (EFCS). 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: This action is effective on
Bombardier on March 17, 2017. We
must receive your comments by May 1,
2017.
ADDRESSES: Send comments identified
by docket number FAA–2016–9296
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: The FAA will post all
comments it receives, without change,
SUMMARY:
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Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Rules and Regulations
to https://www.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 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: Joe
Jacobsen, FAA, Airplane and Flightcrew
Interface, ANM–111, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98057–3356;
telephone 425–227–2011; facsimile
425–227–1320.
SUPPLEMENTARY INFORMATION: The FAA
has determined that notice of, and
opportunity for prior public comment
on, these special conditions is
impracticable because these procedures
would significantly delay issuance of
the design approval and thus delivery of
the affected airplanes.
In addition, 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
publication in the Federal Register.
mstockstill on DSK3G9T082PROD with RULES
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 will consider all comments we
receive by the closing date for
comments. We may change these special
conditions based on the comments we
receive.
Background
On May 30, 2012, Bombardier applied
for an amendment to Type Certificate
VerDate Sep<11>2014
19:31 Mar 16, 2017
Jkt 241001
No. T00003NY to include the new
Model BD–700–2A12 and BD–700–
2A13 series airplanes. The Model BD–
700–2A12 and BD–700–2A13 series
airplanes, which are derivatives of the
BD–700 currently approved under Type
Certificate No. T00003NY, are ultralong-range, executive-interior business
jets, with a passenger capacity of 19.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.101,
Bombardier must show that the Model
BD–700–2A12 and BD–700–2A13 series
airplanes meet the applicable provisions
of the regulations listed in Type
Certificate No. T00003NY, or the
applicable regulations in effect on the
date of application for the change,
except for earlier amendments as agreed
upon by the FAA.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 25) do not contain
adequate or appropriate safety standards
for the Bombardier Model BD–700–
2A12 and BD–700–2A13 series
airplanes 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 novel or unusual
design feature, or should any other
model already included on the same
type certificate be modified to
incorporate the same novel or unusual
design feature, these special conditions
would also apply to the other model
under § 21.101.
In addition to the applicable
airworthiness regulations and special
conditions, the Bombardier Model BD–
700–2A12 and BD–700–2A13 series
airplanes must comply with the fuelvent and exhaust-emission requirements
of 14 CFR part 34 and the noisecertification requirements of 14 CFR
part 36.
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
§ 21.101.
Novel or Unusual Design Features
The Bombardier Model BD–700–2A12
and BD–700–2A13 series airplanes will
incorporate the following novel or
unusual design feature:
Lateral-directional and longitudinal
stability, and low-energy awareness,
through an electronic flight-control
system.
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14127
Discussion
The EFCS on the Bombardier Model
BD–700–2A12 and BD–700–2A13 series
airplanes contain fly-by-wire control
laws that can impact static stability;
therefore, the conventional
requirements in the regulations are not
always met.
Positive static-directional stability is
defined as the tendency to recover from
a skid with the rudder free. Positive
static-lateral stability is defined as the
tendency to raise the low wing in a
sideslip with the aileron controls free.
These control criteria are intended to
accomplish the following:
• Provide additional cues of
inadvertent sideslips and skids through
control-force changes.
• Ensure that short periods of
unattended operation do not result in
any significant changes in yaw or bank
angle.
• Provide predictable roll and yaw
response.
• Provide an acceptable level of pilot
attention (workload) to attain and
maintain a coordinated turn.
Static longitudinal stability on
airplanes with mechanical links to the
pitch-control surface means that a pull
force on the controller results in a
reduction in speed relative to the trim
speed, and a push force on the
controller results in higher than trim
speed. Longitudinal stability is required
by the regulations for the following
reasons:
• Speed change cues are provided to
the pilot through increased and
decreased forces on the controller.
• Short periods of unattended control
of the airplane do not result in
significant changes in attitude, airspeed,
or load factor.
• A predictable pitch response is
provided to the pilot.
• An acceptable level of pilot
attention (workload) to attain and
maintain trim speed and altitude is
provided to the pilot.
• Longitudinal stability provides gust
stability.
Past experience on airplanes fitted
with a flight-control system providing
neutral longitudinal stability reveals
insufficient feedback cues to the pilot
for excursion below normal operational
speeds. The maximum angle-of-attack
protection system limits the airplane
angle of attack and prevents stall during
normal operating speeds, but this
system is not sufficient to prevent stall
at low-speed excursions below normal
operational speeds. Until intervention,
the pilot receives no stability cues
because the airplane remains trimmed.
Additionally, due to thrust variation,
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Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Rules and Regulations
flight-control laws reduce feedback from
the pitching moment. Low-speed
excursions may become more hazardous
without the typical longitudinal
stability, and recovery may become
more difficult when the low-speed
situation is associated with a low
altitude, and with the engines at low
thrust or in performance-limiting
conditions.
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.
Applicability
As discussed above, these special
conditions are applicable to Bombardier
Model BD–700–2A12 and BD–700–
2A13 series airplanes. Should
Bombardier apply at a later date for a
change to the type certificate to include
another model incorporating the same
novel or unusual design feature, these
special conditions would apply to that
model as well.
mstockstill on DSK3G9T082PROD with RULES
Conclusion
This action affects only a certain
novel or unusual design feature on
Bombardier Model BD–700–2A12 and
BD–700–2A13 series airplanes. It is not
a rule of general applicability.
The substance of these special
conditions has been subjected to the
notice and comment period in several
prior instances 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, because a
delay would significantly affect the
certification of the airplane, the FAA
has determined that prior public notice
and comment are unnecessary and
impracticable, and good cause exists for
adopting these special conditions upon
publication in the Federal Register.
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 25
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for these
special conditions is as follows:
conditions are issued as part of the type
certification basis for Bombardier Inc.
Model BD–700–2A12 and BD–700–
2A13 series airplanes.
In lieu of the requirements of
§§ 25.171, 25.173, 25.175 and 25.177(c),
the following special conditions apply:
1. The airplane must be shown to
have suitable static lateral, directional,
and longitudinal stability in any
condition normally encountered in
service, including from the effects of
atmospheric disturbance. The showing
of suitable static lateral, directional, and
longitudinal stability must be based on
the airplane handling qualities,
including pilot workload and pilot
compensation, for specific test
procedures during the flight-test
evaluations.
2. The airplane must provide to the
pilot adequate awareness of a lowenergy (low speed, low thrust, low
height) state when fitted with flightcontrol laws presenting neutral
longitudinal stability significantly
below the normal operating speeds.
‘‘Adequate awareness’’ means warning
information that alerts the flightcrew of
unsafe operating conditions, allowing
the flightcrew to take appropriate
corrective action.
3. The following requirement must be
met for the configurations and speed
specified in paragraph (a) of § 25.177. In
straight, steady sideslips over the range
of sideslip angles appropriate to the
operation of the airplane, the ruddercontrol movements and forces must be
substantially proportional to the angle
of sideslip in a stable sense. This factor
of proportionality must lie between
limits found necessary for safe
operation. The range of sideslip angles
evaluated must include those sideslip
angles resulting from the lesser of:
a. One-half of the available ruddercontrol input; and
b. A rudder-control force of 180
pounds.
Issued in Renton, Washington, on February
10, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 2017–05327 Filed 3–16–17; 8:45 am]
BILLING CODE 4910–13–P
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
VerDate Sep<11>2014
19:31 Mar 16, 2017
Jkt 241001
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2015–7689; Special
Conditions No. 25–645–SC]
Special Conditions: Lufthansa Technik
AG; Boeing Model 747–8 Series
Airplanes, Large Non-Structural Glass
in the Passenger Compartment
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions.
AGENCY:
These special conditions are
issued for the Boeing Model 747–8
airplane. This airplane, as modified by
Lufthansa Technik AG (Lufthansa), will
have a novel or unusual design feature
when compared to the state of
technology envisioned in the
airworthiness standards for transportcategory airplanes. This design feature
is the installation of large, nonstructural glass panels in the cabin area
of an executive interior occupied by
passengers and crew. 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: Effective April 17, 2017.
FOR FURTHER INFORMATION CONTACT:
Jayson Claar, FAA, Airframe and Cabin
Safety, ANM–115, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98057–3356;
telephone 425–227–2194; facsimile
425–227–1320.
SUPPLEMENTARY INFORMATION:
SUMMARY:
Background
On March 8, 2012, Lufthansa Technik
AG applied for a supplemental type
certificate for large, non-structural glass
panels in the passenger compartment in
a Boeing Model 747–8 airplane. The
Model 747–8 airplane is a derivative of
the Boeing Model 747–400 airplane
approved under type certificate no.
A20WE. The airplane, as modified by
Lufthansa Technik AG, is a four-engine,
transport-category airplane that will
have a maximum takeoff weight of
970,000 lbs, capacity for 24
crewmembers, and seating for 143
passengers.
Type Certification Basis
The certification basis for the Boeing
Model 747–8 airplane, as defined in
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Agencies
[Federal Register Volume 82, Number 51 (Friday, March 17, 2017)]
[Rules and Regulations]
[Pages 14126-14128]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-05327]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2016-9296; Special Conditions No. 25-647-SC]
Special Conditions: Bombardier Inc., Model BD-700-2A12 and BD-
700-2A13 Series Airplanes, Electronic Flight Control System: Lateral-
Directional and Longitudinal Stability, and Low-Energy Awareness
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Bombardier Inc.
(Bombardier) Model BD-700-2A12 and BD-700-2A13 series airplanes. These
airplanes will have a novel or unusual design feature when compared to
the state of technology envisioned in the airworthiness standards for
transport-category airplanes. This design feature is lateral-
directional and longitudinal stability, and low-energy awareness,
provided through an electronic flight-control system (EFCS). 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: This action is effective on Bombardier on March 17, 2017. We
must receive your comments by May 1, 2017.
ADDRESSES: Send comments identified by docket number FAA-2016-9296
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: The FAA will post all comments it receives, without
change,
[[Page 14127]]
to https://www.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 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: Joe Jacobsen, FAA, Airplane and
Flightcrew Interface, ANM-111, Transport Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-2011; facsimile 425-227-1320.
SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and
opportunity for prior public comment on, these special conditions is
impracticable because these procedures would significantly delay
issuance of the design approval and thus delivery of the affected
airplanes.
In addition, 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
publication in the Federal Register.
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 will consider all comments we receive by the closing date for
comments. We may change these special conditions based on the comments
we receive.
Background
On May 30, 2012, Bombardier applied for an amendment to Type
Certificate No. T00003NY to include the new Model BD-700-2A12 and BD-
700-2A13 series airplanes. The Model BD-700-2A12 and BD-700-2A13 series
airplanes, which are derivatives of the BD-700 currently approved under
Type Certificate No. T00003NY, are ultra-long-range, executive-interior
business jets, with a passenger capacity of 19.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.101, Bombardier must show that the Model BD-700-2A12 and BD-
700-2A13 series airplanes meet the applicable provisions of the
regulations listed in Type Certificate No. T00003NY, or the applicable
regulations in effect on the date of application for the change, except
for earlier amendments as agreed upon by the FAA.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 25) do not contain adequate or
appropriate safety standards for the Bombardier Model BD-700-2A12 and
BD-700-2A13 series airplanes 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 novel or
unusual design feature, or should any other model already included on
the same type certificate be modified to incorporate the same novel or
unusual design feature, these special conditions would also apply to
the other model under Sec. 21.101.
In addition to the applicable airworthiness regulations and special
conditions, the Bombardier Model BD-700-2A12 and BD-700-2A13 series
airplanes must comply with the fuel-vent and exhaust-emission
requirements of 14 CFR part 34 and the noise-certification requirements
of 14 CFR part 36.
The FAA issues special conditions, as defined in 14 CFR 11.19, in
accordance with Sec. 11.38, and they become part of the type
certification basis under Sec. 21.101.
Novel or Unusual Design Features
The Bombardier Model BD-700-2A12 and BD-700-2A13 series airplanes
will incorporate the following novel or unusual design feature:
Lateral-directional and longitudinal stability, and low-energy
awareness, through an electronic flight-control system.
Discussion
The EFCS on the Bombardier Model BD-700-2A12 and BD-700-2A13 series
airplanes contain fly-by-wire control laws that can impact static
stability; therefore, the conventional requirements in the regulations
are not always met.
Positive static-directional stability is defined as the tendency to
recover from a skid with the rudder free. Positive static-lateral
stability is defined as the tendency to raise the low wing in a
sideslip with the aileron controls free. These control criteria are
intended to accomplish the following:
Provide additional cues of inadvertent sideslips and skids
through control-force changes.
Ensure that short periods of unattended operation do not
result in any significant changes in yaw or bank angle.
Provide predictable roll and yaw response.
Provide an acceptable level of pilot attention (workload)
to attain and maintain a coordinated turn.
Static longitudinal stability on airplanes with mechanical links to
the pitch-control surface means that a pull force on the controller
results in a reduction in speed relative to the trim speed, and a push
force on the controller results in higher than trim speed. Longitudinal
stability is required by the regulations for the following reasons:
Speed change cues are provided to the pilot through
increased and decreased forces on the controller.
Short periods of unattended control of the airplane do not
result in significant changes in attitude, airspeed, or load factor.
A predictable pitch response is provided to the pilot.
An acceptable level of pilot attention (workload) to
attain and maintain trim speed and altitude is provided to the pilot.
Longitudinal stability provides gust stability.
Past experience on airplanes fitted with a flight-control system
providing neutral longitudinal stability reveals insufficient feedback
cues to the pilot for excursion below normal operational speeds. The
maximum angle-of-attack protection system limits the airplane angle of
attack and prevents stall during normal operating speeds, but this
system is not sufficient to prevent stall at low-speed excursions below
normal operational speeds. Until intervention, the pilot receives no
stability cues because the airplane remains trimmed. Additionally, due
to thrust variation,
[[Page 14128]]
flight-control laws reduce feedback from the pitching moment. Low-speed
excursions may become more hazardous without the typical longitudinal
stability, and recovery may become more difficult when the low-speed
situation is associated with a low altitude, and with the engines at
low thrust or in performance-limiting conditions.
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.
Applicability
As discussed above, these special conditions are applicable to
Bombardier Model BD-700-2A12 and BD-700-2A13 series airplanes. Should
Bombardier apply at a later date for a change to the type certificate
to include another 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 Bombardier Model BD-700-2A12 and BD-700-2A13 series airplanes. It is
not a rule of general applicability.
The substance of these special conditions has been subjected to the
notice and comment period in several prior instances 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, because a delay would
significantly affect the certification of the airplane, the FAA has
determined that prior public notice and comment are unnecessary and
impracticable, and good cause exists for adopting these special
conditions upon publication in the Federal Register.
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 25
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 Bombardier Inc. Model BD-700-2A12 and
BD-700-2A13 series airplanes.
In lieu of the requirements of Sec. Sec. 25.171, 25.173, 25.175
and 25.177(c), the following special conditions apply:
1. The airplane must be shown to have suitable static lateral,
directional, and longitudinal stability in any condition normally
encountered in service, including from the effects of atmospheric
disturbance. The showing of suitable static lateral, directional, and
longitudinal stability must be based on the airplane handling
qualities, including pilot workload and pilot compensation, for
specific test procedures during the flight-test evaluations.
2. The airplane must provide to the pilot adequate awareness of a
low-energy (low speed, low thrust, low height) state when fitted with
flight-control laws presenting neutral longitudinal stability
significantly below the normal operating speeds. ``Adequate awareness''
means warning information that alerts the flightcrew of unsafe
operating conditions, allowing the flightcrew to take appropriate
corrective action.
3. The following requirement must be met for the configurations and
speed specified in paragraph (a) of Sec. 25.177. In straight, steady
sideslips over the range of sideslip angles appropriate to the
operation of the airplane, the rudder-control movements and forces must
be substantially proportional to the angle of sideslip in a stable
sense. This factor of proportionality must lie between limits found
necessary for safe operation. The range of sideslip angles evaluated
must include those sideslip angles resulting from the lesser of:
a. One-half of the available rudder-control input; and
b. A rudder-control force of 180 pounds.
Issued in Renton, Washington, on February 10, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane Directorate, Aircraft
Certification Service.
[FR Doc. 2017-05327 Filed 3-16-17; 8:45 am]
BILLING CODE 4910-13-P