Special Conditions: Embraer S.A. Model ERJ 190-300 Airplane; Flight Envelope Protection: Normal Load Factor (g) Limiting, 36320-36322 [2017-16414]
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36320
Federal Register / Vol. 82, No. 149 / Friday, August 4, 2017 / Rules and Regulations
The commenter acknowledged that
the use of the aluminum-lithium alloy
would require full certification to the
existing regulations. However, they
contend that the material is not novel
and unusual and does not require
special conditions.
The FAA does not agree. While it is
true that, with the level of lithium in the
alloys presently tested, the proposed
aluminum-lithium alloy does not appear
to pose a significant risk, the existing
regulations, as discussed above, do not
adequately address the use of this
specific alloy technology. Lithium metal
is highly flammable and toxic; therefore,
the FAA is concerned about the use of
lithium in aircraft alloys. The FAA did
not have data on the properties of
aluminum-lithium when exposed to a
post-crash fire threat prior to applying
these special conditions.
Therefore, special conditions are
required until the regulations are
amended to provide sufficient
requirements for the application of this
new alloy technology.
Applicability
As discussed above, these special
conditions are applicable to the
Bombardier Model BD–700–2A12 and
BD–700–2A13 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 the
other model as well.
Conclusion
This action affects only one novel or
unusual design feature on Bombardier
Model BD–700–2A12 and BD–700–
2A13 airplanes. It is not a rule of general
applicabilit.
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 Model
BD–700–2A12 and BD–700–2A13
airplanes.
The Model BD–700–2A12 and BD–
700–2A13 airplanes must show that
toxic levels of gases produced from the
aluminum-lithium material, when
exposed to a post-crash fire threat, are
in no way an additional threat to the
VerDate Sep<11>2014
13:21 Aug 03, 2017
Jkt 241001
passengers, including, but not limited
to, their ability to evacuate, when
compared to traditional aluminum
airplane materials.
Issued in Renton, Washington.
Victor Wicklund,
Manager, Transport Standards Branch,
Aircraft Certification Service.
[FR Doc. 2017–16413 Filed 8–3–17; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2017–0317; Special
Conditions No. 25–694–SC]
Special Conditions: Embraer S.A.
Model ERJ 190–300 Airplane; Flight
Envelope Protection: Normal Load
Factor (g) Limiting
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Embraer S.A. (Embraer)
Model ERJ 190–300 airplane. This
airplane 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
involves flight-envelope protection
functions that limit such flight
parameters as, for example, angle of
attack, normal load factor, attitude, bank
angle, and speed during normal
operation. 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
Embraer S.A. on August 4, 2017. We
must receive your comments by
September 18, 2017.
ADDRESSES: Send comments identified
by docket number FAA–2017–0317
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.
SUMMARY:
PO 00000
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Fmt 4700
Sfmt 4700
• 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,
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).
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 Flight
Crew Interface Branch, 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
substance of these special conditions
has been subject 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.
In addition, since 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 finds it unnecessary to delay the
effective date and finds that good cause
exists for adopting these special
conditions upon publication in the
Federal Register.
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Federal Register / Vol. 82, No. 149 / Friday, August 4, 2017 / Rules and Regulations
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.
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 September 13, 2013, Embraer
applied for an amendment to Type
Certificate No. A57NM to include the
new Model ERJ 190–300 airplane. The
Model ERJ 190–300 airplane, which is a
derivative of the Embraer Model ERJ
190–100 STD airplane currently
approved under Type Certificate No.
A57NM, is a 97- to 114-passenger
transport-category airplane. The
maximum take-off weight is 124,340 lbs
(56,400 kg).
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.101,
Embraer must show that the Model ERJ
190–300 airplane meets the applicable
provisions of the regulations listed in
Type Certificate No. A57NM, 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 Model ERJ 190–300 airplane
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.
VerDate Sep<11>2014
13:21 Aug 03, 2017
Jkt 241001
In addition to the applicable
airworthiness regulations and special
conditions, the Model ERJ 190–300
airplane must comply with the fuel-vent
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 Embraer Model ERJ 190–300
airplane will incorporate the following
novel or unusual design feature: Flightenvelope protection functions that limit
such flight parameters as, for example,
angle of attack, normal load factor,
attitude, bank angle, and speed during
normal operation.
The Model ERJ 190–300 airplane
incorporates normal load-factor limiting
on a full-time basis, which prevents the
pilot from exceeding the positive or
negative airplane limit load factor. The
application of this load-factor limiting
function affects airplane-handling
characteristics and may compromise the
airplane’s maneuverability and
controllability. The current regulations
do not contain adequate safety
standards for these novel protection
features.
Discussion
The Embraer Model ERJ 190–300
design has a complex, fully digital
flight-control system, referred to as flyby-wire (FBW) architecture. This FBW
architecture provides closed-loop flightcontrol laws and multiple protection
functions.
Airplanes with conventional flightcontrol systems (mechanical linkages)
are limited in the pitch axis only by the
elevator surface area and deflection
limit. The elevator-control power is
normally derived for adequate
controllability and maneuverability at
the most critical longitudinal pitching
moment. The result is that, for
traditional airplanes, maneuverability in
excess of limit structural design values,
within a significant portion of the flight
envelope, is possible.
Part 25 does not specify requirements
or policy for demonstrating maneuver
control that imposes any handlingqualities requirements beyond the
design limit structural loads.
Nevertheless, the availability of this
excess maneuver capacity, in the event
of extreme emergency such as upset
recoveries or collision avoidance, is
recognized.
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Frm 00003
Fmt 4700
Sfmt 4700
36321
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 the Embraer
Model ERJ 190–300 airplane. Should
Embraer 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
model of airplane. It is not a rule of
general applicability.
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 Embraer Model
ERJ 190–300 airplanes.
1. Normal Load Factor (g) Limiting.
To meet the intent of adequate
maneuverability and controllability
required by § 25.143(a); and in addition
to the requirements of § 25.143(a), and
in the absence of other limiting factors,
the following special conditions apply,
based on § 25.333(b):
a. The positive limiting load factor
must not be less than:
i. 2.5 g for the normal state of the
electronic flight-control system with the
high-lift devices retracted up to VMO/
MMO. The positive limiting load factor
may gradually be reduced to 2.25 g
above VMO/MMO.
ii. 2.0 g for the normal state of the
electronic flight-control system with the
high-lift devices extended.
b. The negative limiting load factor
must be equal to or more negative than:
i. Minus 1.0 g for the normal state of
the electronic flight-control system with
the high-lift devices retracted.
ii. 0.0 g for the normal state of the
electronic flight-control system with
high-lift devices extended
c. Maximum reachable positive load
factor, wings level, may be limited by
the characteristics of the electronic
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Federal Register / Vol. 82, No. 149 / Friday, August 4, 2017 / Rules and Regulations
flight-control system or flight-envelope
protections (other than load-factor
protection), provided that:
i. The required values are readily
achievable in turns, and
ii. Wings-level pitch-up is
satisfactory.
d. Maximum achievable negative load
factor may be limited by the
characteristics of the electronic flightcontrol system or flight-envelope
protections (other than load-factor
protection), provided that:
i. Pitch-down responsiveness is
satisfactory, and
ii. From level flight, 0g is readily
achievable, or alternatively, a
satisfactory trajectory change is readily
achievable at operational speeds. For
the FAA to consider a trajectory change
as satisfactory, the applicant should
propose and justify a pitch rate that
provides sufficient maneuvering
capability in the most critical scenarios.
e. Compliance demonstration with the
above requirements may be performed
without ice accretion on the airframe.
f. These special conditions do not
impose an upper bound for the normal
load-factor limit, nor do they require
that the limiter exist. If the limit is set
at a value beyond the structural design
limit maneuvering load factor n of
§§ 25.333(b), 25.337(b), and 25.337(c),
then there should be a very obvious
positive tactile feel built into the
controller so that it serves as a deterrent
to inadvertently exceeding the structural
limit.
Issued in Renton, Washington.
Victor Wicklund,
Manager, Transport Standards Branch,
Aircraft Certification Service.
[FR Doc. 2017–16414 Filed 8–3–17; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2017–0356; Special
Conditions No. 25–696–SC]
Special Conditions: Airbus Model
A330–841 and A330–941 (A330 NEO)
Airplanes; Interaction of Systems and
Structures
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Airbus Model A330 NEO
airplanes. This airplane will have novel
or unusual design features when
SUMMARY:
VerDate Sep<11>2014
13:21 Aug 03, 2017
Jkt 241001
compared to the state of technology
envisioned in the airworthiness
standards for transport-category
airplanes. These design features include
systems that, directly or as a result of
failure or malfunction, affect airplane
structural performance. 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 Airbus
on August 4, 2017. We must receive
your comments by September 18, 2017.
ADDRESSES: Send comments identified
by docket number FAA–2017–0356
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,
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).
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:
Todd Martin, FAA, Airframe and Cabin
Safety, ANM–115, Transport Airplane
PO 00000
Frm 00004
Fmt 4700
Sfmt 4700
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98057–3356;
telephone 425–227–1178; 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 it unnecessary to delay the
effective date and 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 January 20, 2015, Airbus applied
for an amendment to Type Certificate
no. A46NM to include the new Model
A330–841 (A330–800NEO) and A330–
941 (A330–900NEO) airplanes,
collectively marketed as Model
A330NEO airplanes. These airplanes,
which are derivatives of the Model
A330–200 and A330–300 airplanes
currently approved under Type
Certificate no. A46NM, are wide-body,
jet-engine airplanes with a maximum
takeoff weight of 533,519 pounds, and a
passenger capacity of 257 (A330–841);
or a maximum takeoff weight of 535,503
pounds, and a passenger capacity of 287
(A330–941).
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.101,
Airbus must show that the Model
A330NEO airplanes meet the applicable
provisions of the regulations listed in
Type Certificate No. A46NM, or the
applicable regulations in effect on the
date of application for the change except
for earlier amendments as agreed upon
by the FAA.
E:\FR\FM\04AUR1.SGM
04AUR1
Agencies
[Federal Register Volume 82, Number 149 (Friday, August 4, 2017)]
[Rules and Regulations]
[Pages 36320-36322]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-16414]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2017-0317; Special Conditions No. 25-694-SC]
Special Conditions: Embraer S.A. Model ERJ 190-300 Airplane;
Flight Envelope Protection: Normal Load Factor (g) Limiting
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Embraer S.A.
(Embraer) Model ERJ 190-300 airplane. This airplane 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 involves flight-envelope protection
functions that limit such flight parameters as, for example, angle of
attack, normal load factor, attitude, bank angle, and speed during
normal operation. 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 Embraer S.A. on August 4, 2017. We
must receive your comments by September 18, 2017.
ADDRESSES: Send comments identified by docket number FAA-2017-0317
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, 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).
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 Flight
Crew Interface Branch, 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 substance of these special conditions
has been subject 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.
In addition, since 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 finds it unnecessary to
delay the effective date and finds that good cause exists for adopting
these special conditions upon publication in the Federal Register.
[[Page 36321]]
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.
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 September 13, 2013, Embraer applied for an amendment to Type
Certificate No. A57NM to include the new Model ERJ 190-300 airplane.
The Model ERJ 190-300 airplane, which is a derivative of the Embraer
Model ERJ 190-100 STD airplane currently approved under Type
Certificate No. A57NM, is a 97- to 114-passenger transport-category
airplane. The maximum take-off weight is 124,340 lbs (56,400 kg).
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.101, Embraer must show that the Model ERJ 190-300 airplane
meets the applicable provisions of the regulations listed in Type
Certificate No. A57NM, 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 Model ERJ 190-300 airplane 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 Model ERJ 190-300 airplane 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 Embraer Model ERJ 190-300 airplane will incorporate the
following novel or unusual design feature: Flight-envelope protection
functions that limit such flight parameters as, for example, angle of
attack, normal load factor, attitude, bank angle, and speed during
normal operation.
The Model ERJ 190-300 airplane incorporates normal load-factor
limiting on a full-time basis, which prevents the pilot from exceeding
the positive or negative airplane limit load factor. The application of
this load-factor limiting function affects airplane-handling
characteristics and may compromise the airplane's maneuverability and
controllability. The current regulations do not contain adequate safety
standards for these novel protection features.
Discussion
The Embraer Model ERJ 190-300 design has a complex, fully digital
flight-control system, referred to as fly-by-wire (FBW) architecture.
This FBW architecture provides closed-loop flight-control laws and
multiple protection functions.
Airplanes with conventional flight-control systems (mechanical
linkages) are limited in the pitch axis only by the elevator surface
area and deflection limit. The elevator-control power is normally
derived for adequate controllability and maneuverability at the most
critical longitudinal pitching moment. The result is that, for
traditional airplanes, maneuverability in excess of limit structural
design values, within a significant portion of the flight envelope, is
possible.
Part 25 does not specify requirements or policy for demonstrating
maneuver control that imposes any handling-qualities requirements
beyond the design limit structural loads. Nevertheless, the
availability of this excess maneuver capacity, in the event of extreme
emergency such as upset recoveries or collision avoidance, is
recognized.
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 the
Embraer Model ERJ 190-300 airplane. Should Embraer 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 model of airplane. It is not a rule of general applicability.
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 Embraer Model ERJ 190-300 airplanes.
1. Normal Load Factor (g) Limiting. To meet the intent of adequate
maneuverability and controllability required by Sec. 25.143(a); and in
addition to the requirements of Sec. 25.143(a), and in the absence of
other limiting factors, the following special conditions apply, based
on Sec. 25.333(b):
a. The positive limiting load factor must not be less than:
i. 2.5 g for the normal state of the electronic flight-control
system with the high-lift devices retracted up to VMO/
MMO. The positive limiting load factor may gradually be
reduced to 2.25 g above VMO/MMO.
ii. 2.0 g for the normal state of the electronic flight-control
system with the high-lift devices extended.
b. The negative limiting load factor must be equal to or more
negative than:
i. Minus 1.0 g for the normal state of the electronic flight-
control system with the high-lift devices retracted.
ii. 0.0 g for the normal state of the electronic flight-control
system with high-lift devices extended
c. Maximum reachable positive load factor, wings level, may be
limited by the characteristics of the electronic
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flight-control system or flight-envelope protections (other than load-
factor protection), provided that:
i. The required values are readily achievable in turns, and
ii. Wings-level pitch-up is satisfactory.
d. Maximum achievable negative load factor may be limited by the
characteristics of the electronic flight-control system or flight-
envelope protections (other than load-factor protection), provided
that:
i. Pitch-down responsiveness is satisfactory, and
ii. From level flight, 0g is readily achievable, or alternatively,
a satisfactory trajectory change is readily achievable at operational
speeds. For the FAA to consider a trajectory change as satisfactory,
the applicant should propose and justify a pitch rate that provides
sufficient maneuvering capability in the most critical scenarios.
e. Compliance demonstration with the above requirements may be
performed without ice accretion on the airframe.
f. These special conditions do not impose an upper bound for the
normal load-factor limit, nor do they require that the limiter exist.
If the limit is set at a value beyond the structural design limit
maneuvering load factor n of Sec. Sec. 25.333(b), 25.337(b), and
25.337(c), then there should be a very obvious positive tactile feel
built into the controller so that it serves as a deterrent to
inadvertently exceeding the structural limit.
Issued in Renton, Washington.
Victor Wicklund,
Manager, Transport Standards Branch, Aircraft Certification Service.
[FR Doc. 2017-16414 Filed 8-3-17; 8:45 am]
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