Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-500-1A11 Series Airplanes; Flight Envelope Protection: General Limiting Requirements, 75287-75289 [2013-29487]
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Federal Register / Vol. 78, No. 238 / Wednesday, December 11, 2013 / Proposed Rules
BD–500–1A10 and BD–500–1A11 series
airplanes. Should Bombardier Inc. 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 two
model series of airplanes. 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:
emcdonald on DSK67QTVN1PROD with PROPOSALS
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
The Proposed Special Conditions
Accordingly, the Federal Aviation
Administration (FAA) proposes the
following special conditions as part of
the type certification basis for the
Bombardier Inc. Models BD–500–1A10
and BD–500–1A11 series airplanes.
1. Flight Envelope Protection: 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 based on § 25.333(b) apply:
a. The positive limiting load factor
must not be less than:
(1) 2.5g for the normal state of the
electronic flight control system with the
high lift devices retracted.
(2) 2.0g 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:
(1) Minus 1.0g for the normal state of
the electronic flight control system with
the high lift devices retracted.
(2) 0.0g 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 flight
control system or flight envelope
protections (other than load factor
protection) provided that:
(1) The required values are readily
achievable in turns, and
(2) That 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:
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15:58 Dec 10, 2013
Jkt 232001
(1) Pitch down responsiveness is
satisfactory, and
(2) 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.
These proposed special conditions do
not impose an upper bound for the
normal load factor limit, nor does it
require that the limit exist. If the limit
is set at a value beyond the structural
design limit maneuvering load factor
‘‘n’’ of §§ 25.333(b) and 25.337(b) and
(c), 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, on
November 29, 2013.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2013–29486 Filed 12–10–13; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2013–1040; Notice No. 25–
13–39–SC]
Special Conditions: Bombardier Inc.,
Models BD–500–1A10 and BD–500–
1A11 Series Airplanes; Flight Envelope
Protection: General Limiting
Requirements
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
AGENCY:
This action proposes special
conditions for the Bombardier Inc.
Models BD–500–1A10 and BD–500–
1A11 series airplanes. These airplanes
will have a novel or unusual design
feature associated with a new control
architecture and a full digital flight
control system that provides flight
envelope protections. The applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for this design feature. The applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for this design feature. These proposed
SUMMARY:
PO 00000
Frm 00004
Fmt 4702
Sfmt 4702
75287
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 your comments on or
before January 27, 2014.
ADDRESSES: Send comments identified
by docket number FAA–2013–1040
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),
as well as at https://DocketsInfo.dot
.gov/.
Docket: Background documents or
comments received may be read at
https://www.regulations.gov/ at any time.
Follow the online instructions for
accessing the docket or go to the Docket
Operations in Room W12–140 of the
West Building Ground Floor at 1200
New Jersey Avenue SE., Washington,
DC, between 9 a.m. and 5 p.m., Monday
through Friday, except federal holidays.
FOR FURTHER INFORMATION CONTACT: 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
425–227–1149.
SUPPLEMENTARY INFORMATION:
E:\FR\FM\11DEP1.SGM
11DEP1
75288
Federal Register / Vol. 78, No. 238 / Wednesday, December 11, 2013 / Proposed 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 on or before the closing date for
comments. We may change these special
conditions based on the comments we
receive.
emcdonald on DSK67QTVN1PROD with PROPOSALS
Background
On December 10, 2009, Bombardier
Inc. applied for a type certificate for
their new Models BD–500–1A10 and
BD–500–1A11 series airplanes (hereafter
collectively referred to as ‘‘C-series’’).
The C-series airplanes are swept-wing
monoplanes with a pressurized cabin.
They share an identical supplier base
and significant common design
elements. The fuselage is aluminum
alloy material, blended double-bubble
fuselage, sized for nominal 5-abreast
seating. Each airplane’s powerplant
consists of two under wing Pratt and
Whitney PW1524G ultra-high bypass,
geared turbofan engines. Flight controls
are fly-by-wire flight with two passive/
uncoupled side sticks. Avionics
includes five landscape primary cockpit
displays. The dimension of the
airplanes encompass a wingspan of 115
feet; a height of 37.75 feet; and a length
of 114.75 feet for the Model BD–500–
1A10 and a length of 127 feet for the
Model BD–500–1A11. Passenger
capacity is designated as 110 for the
Model BD–500–1A10 and 125 for the
Model BD–500–1A11. Maximum takeoff
weight is 131,000 pounds for the Model
BD–500–1A10 and 144,000 pounds for
the Model BD–500–1A11. Maximum
takeoff thrust is 21,000 pounds for the
Model BD–500–1A10 and 23,300
pounds for the Model BD–500–1A11.
Range is 3,394 miles (5,463 kilometers)
for both models of airplanes. Maximum
operating altitude is 41,000 feet for both
model airplanes.
Bombardier has developed
comprehensive flight envelope
protection features integral to the Cseries electronic flight control system
(EFCS) design. These flight envelope
protection features include limitations
on angle-of-attack, normal load factor,
bank angle, pitch angle, and speed. To
accomplish this flight envelope limiting,
a significant change (or multiple
changes) occurs in the EFCS control
laws as the limit is approached or
exceeded. When EFCS failure states
occur, flight envelope protection
VerDate Mar<15>2010
15:58 Dec 10, 2013
Jkt 232001
features can likewise either be modified,
or in some cases, eliminated. The
current regulations were not written
with these comprehensive flight
envelope limiting systems in mind.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.17,
Bombardier Inc. must show that the Cseries airplanes meet the applicable
provisions of part 25 as amended by
Amendments 25–1 through 25–129
thereto.
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 C-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 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 C-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, 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 C-series airplanes will
incorporate the following novel or
unusual design features: new control
architecture and a full digital flight
control system that provides
comprehensive flight envelope
protections.
Discussion
The applicable airworthiness
regulation in this instance is 14 CFR
25.143. The purpose of § 25.143 is to
verify that any operational maneuvers
conducted within the operational
envelope can be accomplished smoothly
with average piloting skill and without
exceeding any structural limits. The
pilot should be able to predict the
airplane response to any control input.
During the course of the flight test
program, the pilot determines
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Fmt 4702
Sfmt 4702
compliance with § 25.143 through
primarily qualitative methods. During
flight test, the pilot should evaluate all
of the following:
• The interface between each
protection function;
• Transitions from one mode to
another;
• The aircraft response to intentional
dynamic maneuvering, whenever
applicable, through dedicated
maneuvers;
• General controllability assessment;
• High speed characteristics; and
• High angle-of-attack.
Section 25.143, however, does not
adequately ensure that the novel or
unusual features of the C-series
airplanes will have a level of safety
equivalent to that of existing standards.
These special conditions are therefore
required to accommodate the flight
envelope limiting systems in the Cseries airplanes. The additional safety
standards in these special conditions
will ensure a level of safety equivalent
to that of existing standards.
Applicability
As discussed above, these special
conditions are applicable to the Models
BD–500–1A10 and BD–500–1A11 series
airplanes. Should Bombardier Inc. 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 two
model series of airplanes. 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 Proposed Special Conditions
Accordingly, the Federal Aviation
Administration (FAA) proposes the
following special conditions as part of
the type certification basis for the
Bombardier Inc. Models BD–500–1A10
and BD–500–1A11 series airplanes.
1. General Limiting 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 airplane flight
path, speed, or attitude as needed.
E:\FR\FM\11DEP1.SGM
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Federal Register / Vol. 78, No. 238 / Wednesday, December 11, 2013 / Proposed Rules
b. Limit values of protected flight
parameters (and if applicable, associated
warning thresholds) must be compatible
with the following:
i. Airplane structural limits,
ii. Required safe and controllable
maneuvering of the airplane, and
iii. Margins to critical conditions.
Unsafe flight characteristics/conditions
must not result if dynamic
maneuvering, airframe and system
tolerances (both manufacturing and inservice), and non-steady atmospheric
conditions, in any appropriate
combination and phase of flight, can
produce a limited flight parameter
beyond the nominal design limit value.
c. The airplane must be responsive to
intentional dynamic maneuvering to
within a suitable range of the parameter
limit. Dynamic characteristics such as
damping and overshoot must also be
appropriate for the flight maneuver and
limit parameter in question.
d. When simultaneous envelope
limiting is engaged, adverse coupling or
adverse priority must not result.
2. Failure States: Electronic flight
control system failures (including
sensor) must not result in a condition
where a parameter is limited to such a
reduced value that safe and controllable
maneuvering is no longer available. The
crew must be alerted by suitable means
if any change in envelope limiting or
maneuverability is produced by single
or multiple failures of the electronic
flight control system not shown to be
extremely improbable.
Issued in Renton, Washington, on
November 29, 2013.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2013–29487 Filed 12–10–13; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
Examining the AD Docket
[Docket No. FAA–2013–1026; Directorate
Identifier 2012–NM–173–AD]
emcdonald on DSK67QTVN1PROD with PROPOSALS
RIN 2120–AA64
Airworthiness Directives; BAE
Systems (Operations) Limited
Airplanes
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
We propose to adopt a new
airworthiness directive (AD) for all BAE
SUMMARY:
VerDate Mar<15>2010
15:58 Dec 10, 2013
Jkt 232001
SYSTEMS (OPERATIONS) LIMITED
Model BAe 146 series airplanes and
Model Avro 146–RJ series airplanes.
This proposed AD was prompted by
reports of cracking of the main fitting of
the nose landing gear (NLG). This
proposed AD would require revising the
maintenance program by incorporating a
new safe-life limitation for the NLG
main fitting. We are proposing this AD
to prevent collapse of the NLG, which
could lead to degradation of direction
control on the ground or an uncommanded turn to the left and a
consequent loss of control of the
airplane on the ground, possibly
resulting in damage to the airplane and
injury to occupants.
DATES: We must receive comments on
this proposed AD by January 27, 2014.
ADDRESSES: You may send comments by
any of the following methods:
• Federal eRulemaking Portal: Go to
https://www.regulations.gov. Follow the
instructions for submitting comments.
• Fax: (202) 493–2251.
• Mail: U.S. Department of
Transportation, Docket Operations, M–
30, West Building Ground Floor, Room
W12–140, 1200 New Jersey Avenue SE.,
Washington, DC 20590.
• Hand Delivery: Deliver to Mail
address above between 9 a.m. and 5
p.m., Monday through Friday, except
Federal holidays.
For service information identified in
this proposed AD, contact BAE
SYSTEMS (OPERATIONS) LIMITED,
Customer Information Department,
Prestwick International Airport,
Ayrshire, KA9 2RW, Scotland, United
Kingdom; telephone +44 1292 675207;
fax +44 1292 675704; email
RApublications@baesystems.com;
Internet https://www.baesystems.com/
Businesses/RegionalAircraft/index.htm.
You may view this referenced service
information at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue
SW., Renton, WA. For information on
the availability of this material at the
FAA, call 425–227–1221.
You may examine the AD docket on
the Internet at https://
www.regulations.gov; or in person at
the Docket Operations office between 9
a.m. and 5 p.m., Monday through
Friday, except Federal holidays. The AD
docket contains this proposed AD, the
regulatory evaluation, any comments
received, and other information. The
street address for the Docket Operations
office (telephone (800) 647–5527) is in
the ADDRESSES section. Comments will
be available in the AD docket shortly
after receipt.
PO 00000
Frm 00006
Fmt 4702
Sfmt 4702
75289
FOR FURTHER INFORMATION CONTACT:
Todd Thompson, Aerospace Engineer,
International Branch, ANM–116,
Transport Airplane Directorate, FAA,
1601 Lind Avenue SW., Renton, WA
98057–3356; telephone 425–227–1175;
fax 425–227–1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written
relevant data, views, or arguments about
this proposed AD. Send your comments
to an address listed under the
ADDRESSES section. Include ‘‘Docket No.
FAA–2013–1026; Directorate Identifier
2012–NM–173–AD’’ at the beginning of
your comments. We specifically invite
comments on the overall regulatory,
economic, environmental, and energy
aspects of this proposed AD. We will
consider all comments received by the
closing date and may amend this
proposed AD based on those comments.
We will post all comments we
receive, without change, to https://
www.regulations.gov, including any
personal information you provide. We
will also post a report summarizing each
substantive verbal contact we receive
about this proposed AD.
Discussion
The European Aviation Safety Agency
(EASA), which is the Technical Agent
for the Member States of the European
Community, has issued EASA
Airworthiness Directive 2012–0191R1,
dated November 6, 2012 (referred to
after this as the Mandatory Continuing
Airworthiness Information, or ‘‘the
MCAI’’), to correct an unsafe condition
for the specified products. The MCAI
states:
Several occurrences of the aeroplane’s
Nose Landing Gear (NLG) Main Fitting
cracking have been reported. Subsequently in
different cases, NLG Main Fitting crack lead
to collapsed NLG, locked NLG steering and
an aeroplane’s un-commanded steering to the
left.
Cracks in the NLG Bell Housing are not
detectable with the NLG fitted to the
aeroplane and are difficult to detect during
overhaul without substantial disassembly of
the gear.
This condition, if not corrected, could lead
to degradation of directional control on the
ground or an un-commanded turn to the left
and a consequent loss of control of the
aeroplane on the ground, possibly resulting
in damage to the aeroplane and injury to
occupants.
Prompted by these findings, BAE Systems
(Operations) Ltd issued Inspection Service
Bulletin (ISB) 32–186 (hereafter referred to as
the ISB) to introduce a new safe life of 16,000
flight cycles (FC) for certain NLG main
fittings, having a Part Number (P/N) as
identified in Paragraph 1A, tables 1, 2 and 3
of the ISB.
E:\FR\FM\11DEP1.SGM
11DEP1
Agencies
[Federal Register Volume 78, Number 238 (Wednesday, December 11, 2013)]
[Proposed Rules]
[Pages 75287-75289]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-29487]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2013-1040; Notice No. 25-13-39-SC]
Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-
500-1A11 Series Airplanes; Flight Envelope Protection: General Limiting
Requirements
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This action proposes special conditions for the Bombardier
Inc. Models BD-500-1A10 and BD-500-1A11 series airplanes. These
airplanes will have a novel or unusual design feature associated with a
new control architecture and a full digital flight control system that
provides flight envelope protections. The applicable airworthiness
regulations do not contain adequate or appropriate safety standards for
this design feature. 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 your comments on or before January 27, 2014.
ADDRESSES: Send comments identified by docket number FAA-2013-1040
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), as well as at https://DocketsInfo.dot.gov/.
Docket: Background documents or comments received may be read at
https://www.regulations.gov/ at any time. Follow the online instructions
for accessing the docket or go to the Docket Operations in Room W12-140
of the West Building Ground Floor at 1200 New Jersey Avenue SE.,
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday,
except federal holidays.
FOR FURTHER INFORMATION CONTACT: 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 425-227-1149.
SUPPLEMENTARY INFORMATION:
[[Page 75288]]
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 on or before the closing
date for comments. We may change these special conditions based on the
comments we receive.
Background
On December 10, 2009, Bombardier Inc. applied for a type
certificate for their new Models BD-500-1A10 and BD-500-1A11 series
airplanes (hereafter collectively referred to as ``C-series''). The C-
series airplanes are swept-wing monoplanes with a pressurized cabin.
They share an identical supplier base and significant common design
elements. The fuselage is aluminum alloy material, blended double-
bubble fuselage, sized for nominal 5-abreast seating. Each airplane's
powerplant consists of two under wing Pratt and Whitney PW1524G ultra-
high bypass, geared turbofan engines. Flight controls are fly-by-wire
flight with two passive/uncoupled side sticks. Avionics includes five
landscape primary cockpit displays. The dimension of the airplanes
encompass a wingspan of 115 feet; a height of 37.75 feet; and a length
of 114.75 feet for the Model BD-500-1A10 and a length of 127 feet for
the Model BD-500-1A11. Passenger capacity is designated as 110 for the
Model BD-500-1A10 and 125 for the Model BD-500-1A11. Maximum takeoff
weight is 131,000 pounds for the Model BD-500-1A10 and 144,000 pounds
for the Model BD-500-1A11. Maximum takeoff thrust is 21,000 pounds for
the Model BD-500-1A10 and 23,300 pounds for the Model BD-500-1A11.
Range is 3,394 miles (5,463 kilometers) for both models of airplanes.
Maximum operating altitude is 41,000 feet for both model airplanes.
Bombardier has developed comprehensive flight envelope protection
features integral to the C-series electronic flight control system
(EFCS) design. These flight envelope protection features include
limitations on angle-of-attack, normal load factor, bank angle, pitch
angle, and speed. To accomplish this flight envelope limiting, a
significant change (or multiple changes) occurs in the EFCS control
laws as the limit is approached or exceeded. When EFCS failure states
occur, flight envelope protection features can likewise either be
modified, or in some cases, eliminated. The current regulations were
not written with these comprehensive flight envelope limiting systems
in mind.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.17, Bombardier Inc. must show that the C-series airplanes meet
the applicable provisions of part 25 as amended by Amendments 25-1
through 25-129 thereto.
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 C-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 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 C-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, 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 C-series airplanes will incorporate the following novel or
unusual design features: new control architecture and a full digital
flight control system that provides comprehensive flight envelope
protections.
Discussion
The applicable airworthiness regulation in this instance is 14 CFR
25.143. The purpose of Sec. 25.143 is to verify that any operational
maneuvers conducted within the operational envelope can be accomplished
smoothly with average piloting skill and without exceeding any
structural limits. The pilot should be able to predict the airplane
response to any control input. During the course of the flight test
program, the pilot determines compliance with Sec. 25.143 through
primarily qualitative methods. During flight test, the pilot should
evaluate all of the following:
The interface between each protection function;
Transitions from one mode to another;
The aircraft response to intentional dynamic maneuvering,
whenever applicable, through dedicated maneuvers;
General controllability assessment;
High speed characteristics; and
High angle-of-attack.
Section 25.143, however, does not adequately ensure that the novel
or unusual features of the C-series airplanes will have a level of
safety equivalent to that of existing standards. These special
conditions are therefore required to accommodate the flight envelope
limiting systems in the C-series airplanes. The additional safety
standards in these special conditions will ensure a level of safety
equivalent to that of existing standards.
Applicability
As discussed above, these special conditions are applicable to the
Models BD-500-1A10 and BD-500-1A11 series airplanes. Should Bombardier
Inc. 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 two model series of airplanes. 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 Proposed Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes the
following special conditions as part of the type certification basis
for the Bombardier Inc. Models BD-500-1A10 and BD-500-1A11 series
airplanes.
1. General Limiting 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
airplane flight path, speed, or attitude as needed.
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b. Limit values of protected flight parameters (and if applicable,
associated warning thresholds) must be compatible with the following:
i. Airplane structural limits,
ii. Required safe and controllable maneuvering of the airplane, and
iii. Margins to critical conditions. Unsafe flight characteristics/
conditions must not result if dynamic maneuvering, airframe and system
tolerances (both manufacturing and in-service), and non-steady
atmospheric conditions, in any appropriate combination and phase of
flight, can produce a limited flight parameter beyond the nominal
design limit value.
c. The airplane must be responsive to intentional dynamic
maneuvering to within a suitable range of the parameter limit. Dynamic
characteristics such as damping and overshoot must also be appropriate
for the flight maneuver and limit parameter in question.
d. When simultaneous envelope limiting is engaged, adverse coupling
or adverse priority must not result.
2. Failure States: Electronic flight control system failures
(including sensor) must not result in a condition where a parameter is
limited to such a reduced value that safe and controllable maneuvering
is no longer available. The crew must be alerted by suitable means if
any change in envelope limiting or maneuverability is produced by
single or multiple failures of the electronic flight control system not
shown to be extremely improbable.
Issued in Renton, Washington, on November 29, 2013.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2013-29487 Filed 12-10-13; 8:45 am]
BILLING CODE 4910-13-P