Special Conditions: Dassault Aviation Model Falcon 7X Airplane; Interaction of Systems and Structures, Limit Pilot Forces, and High Intensity Radiated Fields (HIRF) Protection, 61427-61432 [06-8762]
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61427
Proposed Rules
Federal Register
Vol. 71, No. 201
Wednesday, October 18, 2006
Federal Aviation Administration
Federal holidays, between 7:30 a.m. and
4 p.m.
FOR FURTHER INFORMATION CONTACT:
Thomas Rodriguez, FAA, International
Branch, ANM–116, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington, 98057–3356;
telephone (425) 227–1137; facsimile
(425) 227–1149.
SUPPLEMENTARY INFORMATION:
14 CFR Part 25
Comments Invited
This section of the FEDERAL REGISTER
contains notices to the public of the proposed
issuance of rules and regulations. The
purpose of these notices is to give interested
persons an opportunity to participate in the
rule making prior to the adoption of the final
rules.
DEPARTMENT OF TRANSPORTATION
[Docket No. NM355; Notice No. 25–06–10–
SC]
Special Conditions: Dassault Aviation
Model Falcon 7X Airplane; Interaction
of Systems and Structures, Limit Pilot
Forces, and High Intensity Radiated
Fields (HIRF) Protection
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
rmajette on PROD1PC67 with PROPOSALS
AGENCY:
SUMMARY: This action proposes special
conditions for the Dassault Aviation
Model Falcon 7X airplane. This airplane
will have novel or unusual design
features when compared to the state of
technology envisioned in the
airworthiness standards for transport
category airplanes. These design
features include interaction of systems
and structures, limit pilot forces, and
electrical and electronic flight control
systems. The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for these
design features. 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: We must receive your comments
by December 4, 2006.
ADDRESSES: You must mail two copies
of your comments to: Federal Aviation
Administration, Transport Airplane
Directorate, Attn: Rules Docket (ANM–
113), Docket No. NM355, 1601 Lind
Avenue SW., Renton, Washington,
98057–3356. You may deliver two
copies to the Transport Airplane
Directorate at the above address. You
must mark your comments: Docket No.
NM355. You can inspect comments in
the Rules Docket weekdays, except
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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 ask that you send
us two copies of written comments.
We will file in the docket all
comments we receive, as well as a
report summarizing each substantive
public contact with FAA personnel
concerning these special conditions.
You can inspect the docket before and
after the comment closing date. If you
wish to review the docket in person, go
to the address in the ADDRESSES section
of this preamble between 7:30 a.m. and
4 p.m., Monday through Friday, except
Federal holidays.
We will consider all comments we
receive on or before the closing date for
comments. We will consider comments
filed late if it is possible to do so
without incurring expense or delay. We
may change these special conditions
based on the comments we receive.
If you want the FAA to acknowledge
receipt of your comments on this
proposal, include with your comments
a pre-addressed, stamped postcard on
which the docket number appears. We
will stamp the date on the postcard and
mail it back to you.
Background
On June 4, 2002, Dassault Aviation, 9
´
rond Point des Champs Elysees, 75008,
Paris, France, applied for a type
certificate for its new Model Falcon 7X
airplane. The Model Falcon 7X is a 19
passenger transport category airplane,
powered by three aft mounted Pratt &
Whitney PW307A high bypass ratio
turbofan engines. The airplane is
operated using a fly-by-wire (FBW)
primary flight control system. This will
be the first application of a FBW
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Sfmt 4702
primary flight control system in a
private/corporate use airplane.
The Dassault Aviation Model Falcon
7X design incorporates equipment that
was not envisioned when part 25 was
created. This equipment affects the
interaction of systems and structures,
limit pilot forces, and high intensity
radiated fields (HIRF) protection.
Therefore, special conditions are
required to provide the level of safety
equivalent to that established by the
regulations.
Type Certification Basis
Under the provisions of 14 CFR 21.17,
Dassault Aviation must show that the
Model Falcon 7X airplane meets the
applicable provisions of part 25, as
amended by Amendments 25–1 through
25–108.
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 Falcon 7X because of a
novel or unusual design feature, special
conditions are prescribed under the
provisions of § 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, the Model Falcon 7X 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 § 11.19, under § 11.38, and
they become part of the type
certification basis under § 21.17(a)(2).
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.
Novel or Unusual Design Features
The Model Falcon 7X airplane will
incorporate three novel or unusual
design features: interaction of systems
and structures, limit pilot forces, and
electrical and electronic flight control
systems. These proposed special
conditions address equipment which
may affect the airplane’s structural
performance, either directly or as a
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Federal Register / Vol. 71, No. 201 / Wednesday, October 18, 2006 / Proposed Rules
result of failure or malfunction; pilot
limit forces; and electrical and
electronic systems which perform
critical functions that may be vulnerable
to HIRF.
These proposed special conditions are
identical or nearly identical to those
previously required for type
certification of other Dassault airplane
models. In general, the proposed special
conditions were derived initially from
standardized requirements developed
by the Aviation Rulemaking Advisory
Committee (ARAC), comprised of
representatives of the FAA, Europe’s
Joint Aviation Authorities (now
replaced by the European Aviation
Safety Agency), and industry.
Additional special conditions will be
issued for other novel or unusual design
features of the Dassault Model Falcon
7X airplane. These additional proposed
special conditions will pertain to the
following topics:
Dive Speed Definition With Speed
Protection System,
Sudden Engine Stoppage,
High Incidence Protection Function,
Side Stick Controllers,
Lateral-Directional and Longitudinal
Stability and Low Energy Awareness,
Flight Envelope Protection: General
Limiting Requirements,
Flight Envelope Protection: Normal
Load Factor (g) Limiting,
Flight Envelope Protection: Pitch, Roll
and High Speed Limiting Functions,
Flight Control Surface Position
Awareness,
Flight Characteristics Compliance via
Handling Qualities Rating Method,
Operation Without Normal Electrical
Power.
Proposed special conditions have
been issued for the Model Falcon 7X
with the novel or unusual design feature
pertaining to Pilot Compartment View–
Hydrophobic Coatings in Lieu of
Windshield Wipers. This special
condition was published for public
comment in the Federal Register on July
12, 2006 (71 FR 39235).
Discussion
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Because of rapid improvements in
airplane technology, the applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for these design features. Therefore, in
addition to the requirements of part 25,
subparts C and D, the following three
special conditions apply.
Special Condition No. 1. Interaction of
Systems and Structures
The Dassault Model Falcon 7X is
equipped with systems that may affect
the airplane’s structural performance
either directly or as a result of failure or
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malfunction. The effects of these
systems on structural performance must
be considered in the certification
analysis. This analysis must include
consideration of normal operation and
of failure conditions with required
structural strength levels related to the
probability of occurrence.
Previously, special conditions have
been specified to require consideration
of the effects of systems on structures.
The special condition proposed for the
Model Falcon 7X is nearly identical to
that issued for other fly-by-wire
airplanes.
Special Condition No. 2. Limit Pilot
Forces
Like some other certificated transport
category airplane models, the Dassault
Model Falcon 7X airplane is equipped
with a side stick controller instead of a
conventional wheel or control stick.
This kind of controller is designed to be
operated using only one hand. The
requirement of § 25.397(c), which
defines limit pilot forces and torques for
conventional wheel or stick controls, is
not appropriate for a side stick
controller. Therefore, a special
condition is necessary to specify the
appropriate loading conditions for this
kind of controller.
Special Condition No. 3. High Intensity
Radiated Fields (HIRF) Protection
The Dassault Model Falcon X will
utilize electrical and electronic systems
which perform critical functions. These
systems may be vulnerable to HIRF
external to the airplane. There is no
specific regulation that addresses
requirements for protection of electrical
and electronic systems from HIRF. With
the trend toward increased power levels
from ground-based transmitters and the
advent of space and satellite
communications, coupled with
electronic command and control of the
airplane, the immunity of critical
avionics/electronics and electrical
systems to HIRF must be established.
To ensure that a level of safety is
achieved that is equivalent to that
intended by the regulations
incorporated by reference, a special
condition is needed for the Dassault
Model Falcon 7X airplane. This special
condition requires that avionics/
electronics and electrical systems that
perform critical functions be designed
and installed to preclude component
damage and interruption.
It is not possible to precisely define
the HIRF to which the airplane will be
exposed in service. There is also
uncertainty concerning the effectiveness
of airframe shielding for HIRF.
Furthermore, coupling of
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Sfmt 4702
electromagnetic energy to cockpitinstalled equipment through the cockpit
window apertures is undefined. Based
on surveys and analysis of existing HIRF
emitters, adequate protection from
exists when there is compliance with
either paragraph 1 or 2 below:
1. A minimum threat of 100 volts rms
(root-mean-square) per meter electric
field strength from 10 KHz to 18 GHz.
a. The threat must be applied to the
system elements and their associated
wiring harnesses without the benefit of
airframe shielding.
b. Demonstration of this level of
protection is established through system
tests and analysis.
2. A threat external to the airframe of
the field strengths indicated in the table
below for the frequency ranges
indicated. Both peak and average field
strength components from the table are
to be demonstrated.
Frequency
Field strength
(volts per meter)
Peak
10 kHz–100 kHz .......
100 kHz–500 kHz .....
500 kHz–2 MHz ........
2 MHz–30 MHz .........
30 MHz–70 MHz .......
70 MHz–100 MHz .....
100 MHz–200 MHz ...
200 MHz–400 MHz ...
400 MHz–700 MHz ...
700 MHz–1 GHz .......
1 GHz–2 GHz ...........
2 GHz–4 GHz ...........
4 GHz–6 GHz ...........
6 GHz–8 GHz ...........
8 GHz–12 GHz .........
12 GHz–18 GHz .......
18 GHz–40 GHz .......
50
50
50
100
50
50
100
100
700
700
2000
3000
3000
1000
3000
2000
600
Average
50
50
50
100
50
50
100
100
50
100
200
200
200
200
300
200
200
The field strengths are expressed in terms
of peak of the root-mean-square (rms) over
the complete modulation period.
The threat levels identified above are
the result of an FAA review of existing
studies on the subject of HIRF, in light
of the ongoing work of the
Electromagnetic Effects Harmonization
Working Group of the Aviation
Rulemaking Advisory Committee.
Applicability
As discussed above, these special
conditions are applicable to the Dassault
Model Falcon 7X. Should Dassault
Aviation 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 certain novel
or unusual design features of the
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Dassault Model Falcon 7X airplane. It is
not a rule of general applicability, and
it affects only the applicant which
applied to the FAA for approval of these
features on the airplane.
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, pursuant to the
authority delegated to me by the
Administrator, the following special
conditions are issued as part of the type
certification basis for Dassault Aviation
Model Falcon 7X airplanes.
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1. Interaction of Systems and Structures
In addition to the requirements of part
25, subparts C and D, the following
proposed special conditions would
apply:
a. For airplanes equipped with
systems that affect structural
performance—either directly or as a
result of a failure or malfunction—the
influence of these systems and their
failure conditions must be taken into
account when showing compliance with
the requirements of part 25, subparts C
and D. Paragraph c below must be used
to evaluate the structural performance of
airplanes equipped with these systems.
b. Unless shown to be extremely
improbable, the airplane must be
designed to withstand any forced
structural vibration resulting from any
failure, malfunction, or adverse
condition in the flight control system.
These loads must be treated in
accordance with the requirements of
paragraph a above.
c. Interaction of Systems and
Structures.
(1) General: The following criteria
must be used for showing compliance
with this special condition for
interaction of systems and structures
and with § 25.629 for airplanes
equipped with flight control systems,
autopilots, stability augmentation
systems, load alleviation systems, flutter
control systems, and fuel management
systems. If this special condition is used
for other systems, it may be necessary to
adapt the criteria to the specific system.
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(a) The criteria defined herein address
only the direct structural consequences
of the system responses and
performances. They cannot be
considered in isolation but should be
included in the overall safety evaluation
of the airplane. These criteria may, in
some instances, duplicate standards
already established for this evaluation.
These criteria are applicable only to
structures whose failure could prevent
continued safe flight and landing.
Specific criteria that define acceptable
limits on handling characteristics or
stability requirements when operating
in the system degraded or inoperative
modes are not provided in this special
condition.
(b) Depending upon the specific
characteristics of the airplane,
additional studies may be required that
go beyond the criteria provided in this
special condition in order to
demonstrate the capability of the
airplane to meet other realistic
conditions, such as alternative gust or
maneuver descriptions for an airplane
equipped with a load alleviation system.
(c) The following definitions are
applicable to this paragraph.
Structural performance: Capability of
the airplane to meet the structural
requirements of part 25.
Flight limitations: Limitations that
can be applied to the airplane flight
conditions following an in-flight
occurrence and that are included in the
flight manual (e.g., speed limitations
and avoidance of severe weather
conditions).
Operational limitations: Limitations,
including flight limitations, that can be
applied to the airplane operating
conditions before dispatch (e.g., fuel,
payload, and Master Minimum
Equipment List limitations).
Probabilistic terms: The probabilistic
terms (probable, improbable, and
extremely improbable) used in this
Special Conditions are the same as those
used in § 25.1309.
Failure condition: The term failure
condition is the same as that used in
§ 25.1309. However, this Special
Conditions applies only to system
failure conditions that affect the
structural performance of the airplane
(e.g., system failure conditions that
induce loads, change the response of the
airplane to inputs such as gusts or pilot
actions, or lower flutter margins).
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(2) Effects of Systems on Structures.
(a) General. The following criteria
will be used in determining the
influence of a system and its failure
conditions on the airplane structure.
(b) System fully operative. With the
system fully operative, the following
apply:
(1) Limit loads must be derived in all
normal operating configurations of the
system from all the limit conditions
specified in subpart C (or used in lieu
of those specified in subpart C), taking
into account any special behavior of
such a system or associated functions or
any effect on the structural performance
of the airplane that may occur up to the
limit loads. In particular, any significant
non-linearity (rate of displacement of
control surface, thresholds or any other
system non-linearities) must be
accounted for in a realistic or
conservative way when deriving limit
loads from limit conditions.
(2) The airplane must meet the
strength requirements of part 25 (static
strength, residual strength), using the
specified factors to derive ultimate loads
from the limit loads defined above. The
effect of non-linearities must be
investigated beyond limit conditions to
ensure that the behavior of the system
presents no anomaly compared to the
behavior below limit conditions.
However, conditions beyond limit
conditions need not be considered,
when it can be shown that the airplane
has design features that will not allow
it to exceed those limit conditions.
(3) The airplane must meet the
aeroelastic stability requirements of
§ 25.629.
(c) System in the failure condition.
For any system failure condition not
shown to be extremely improbable, the
following apply:
(1) At the time of occurrence. Starting
from 1g level flight conditions, a
realistic scenario, including pilot
corrective actions, must be established
to determine the loads occurring at the
time of failure and immediately after
failure.
(i) For static strength substantiation,
these loads multiplied by an appropriate
factor of safety that is related to the
probability of occurrence of the failure
are ultimate loads to be considered for
design. The factor of safety (FS) is
defined in Figure 1.
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(ii) For residual strength
substantiation, the airplane must be able
to withstand two thirds of the ultimate
loads defined in paragraph (c)(1)(i) of
this section. For pressurized cabins,
these loads must be combined with the
normal operating differential pressure.
(iii) Freedom from aeroelastic
instability must be shown up to the
speeds defined in § 25.629(b)(2). For
failure conditions that result in speed
increases beyond VC/MC, freedom from
aeroelastic instability must be shown to
increased speeds, so that the margins
intended by § 25.629(b)(2) are
maintained.
(iv) Failures of the system that result
in forced structural vibrations
(oscillatory failures) must not produce
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loads that could result in detrimental
deformation of primary structure.
(2) For the continuation of the flight.
For the airplane in the system failed
state and considering any appropriate
reconfiguration and flight limitations,
the following apply:
(i) The loads derived from the
following conditions (or used in lieu of
the following conditions) at speeds up
to VC/MC or the speed limitation
prescribed for the remainder of the
flight must be determined:
(A) the limit symmetrical
maneuvering conditions specified in
§§ 25.331 and in 25.345.
(B) the limit gust and turbulence
conditions specified in §§ 25.341 and in
25.345.
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(C) the limit rolling conditions
specified in § 25.349 and the limit
unsymmetrical conditions specified in
§§ 25.367 and 25.427(b) and (c).
(D) the limit yaw maneuvering
conditions specified in § 25.351.
(E) the limit ground loading
conditions specified in §§ 25.473 and
25.491.
(ii) For static strength substantiation,
each part of the structure must be able
to withstand the loads in paragraph
(c)(2)(i) of this special condition
multiplied by a factor of safety,
depending on the probability of being in
this failure state. The factor of safety is
defined in Figure 2.
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Federal Register / Vol. 71, No. 201 / Wednesday, October 18, 2006 / Proposed Rules
Note: If Pj is greater than 10¥3 per flight
hour, then a 1.5 factor of safety must be
applied to all limit load conditions specified
in subpart C.
V′ = Clearance speed as defined by
§ 25.629(b)(2).
V″ = Clearance speed as defined by
§ 25.629(b)(1).
Qj = (Tj)(Pj)
Where:
Tj = Average time spent in failure condition
j (in hours)
Pj = Probability of occurrence of failure mode
j (per hour)
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Note: If Pj is greater than 10¥3 per flight
hour, then the flutter clearance speed must
not be less than V″.
(vi) Freedom from aeroelastic
instability must also be shown up to V′
in Figure 3 above for any probable
system failure condition combined with
any damage required or selected for
investigation by § 25.571(b).
(3) Consideration of certain failure
conditions may be required by other
sections of this Part, regardless of
calculated system reliability. Where
analysis shows the probability of these
failure conditions to be less than 10¥9,
criteria other than those specified in this
paragraph may be used for structural
substantiation to show continued safe
flight and landing.
(d) Warning considerations. For
system failure detection and warning,
the following apply:
(1) The system must be checked for
failure conditions, not extremely
improbable, that degrade the structural
capability below the level required by
part 25 or significantly reduce the
reliability of the remaining system. As
far as reasonably practicable, the
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(iii) For residual strength
substantiation, the airplane must be able
to withstand two thirds of the ultimate
loads defined in paragraph (c)(2)(ii). For
pressurized cabins, these loads must be
combined with the normal operating
differential pressure.
(iv) If the loads induced by the failure
condition have a significant effect on
fatigue or damage tolerance, then their
effects must be taken into account.
(v) Freedom from aeroelastic
instability must be shown up to a speed
determined from Figure 3. Flutter
clearance speeds V′ and V″ may be
based on the speed limitation specified
for the remainder of the flight, using the
margins defined by § 25.629(b).
flightcrew must be made aware of these
failures before flight. Certain elements
of the control system, such as
mechanical and hydraulic components,
may use special periodic inspections,
and electronic components may use
daily checks in lieu of warning systems
to achieve the objective of this
requirement. These certification
maintenance requirements must be
limited to components that are not
readily detectable by normal warning
systems and where service history
shows that inspections will provide an
adequate level of safety.
(2) The existence of any failure
condition, not extremely improbable,
during flight that could significantly
affect the structural capability of the
airplane and for which the associated
reduction in airworthiness can be
minimized by suitable flight limitations
must be signaled to the flightcrew. For
example, failure conditions that result
in a factor of safety between the airplane
strength and the loads of part 25,
subpart C, below 1.25 or flutter margins
below V″ must be signaled to the crew
during flight.
(e) Dispatch with known failure
conditions. If the airplane is to be
dispatched in a known system failure
condition that affects structural
performance or affects the reliability of
the remaining system to maintain
structural performance, then the
provisions of these Special Conditions
must be met, including the provisions of
paragraph (b), for the dispatched
condition and paragraph (c) for
subsequent failures. Expected
operational limitations may be taken
into account in establishing Pj as the
probability of failure occurrence for
determining the safety margin in Figure
1. Flight limitations and expected
operational limitations may be taken
into account in establishing Qj as the
combined probability of being in the
dispatched failure condition and the
subsequent failure condition for the
safety margins in Figures 2 and 3. These
limitations must be such that the
probability of being in this combined
failure state and then subsequently
encountering limit load conditions is
extremely improbable. No reduction in
these safety margins is allowed if the
subsequent system failure rate is greater
than 1E–3 per flight hour.
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2. Limit Pilot Forces
In addition to the requirements of
§ 25.397(c) the following special
condition applies.
The limit pilot forces are:
a. For all components between and
including the handle and its control
stops.
Pitch
Nose up 200 lbf
(pounds force).
Nose down 200 lbf
Roll
Nose left 100 lbf.
Nose right 100 lbf.
b. For all other components of the
side stick control assembly, but
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Qj = (Tj)(Pj)
Where:
Tj = Average time spent in failure condition
j (in hours)
Pj = Probability of occurrence of failure mode
j (per hour)
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Federal Register / Vol. 71, No. 201 / Wednesday, October 18, 2006 / Proposed Rules
excluding the internal components of
the electrical sensor assemblies to avoid
damage as a result of an in-flight jam.
Pitch
Roll
Nose up 125 lbf ........
Nose down 125 lbf ....
Nose left 50 lbf.
Nose right 50 lbf.
3. High Intensity Radiated Fields (HIRF)
Protection
a. Protection from Unwanted Effects
of High Intensity Radiated Fields. Each
electrical and electronic system which
performs critical functions must be
designed and installed to ensure that the
operation and operational capability of
these systems to perform critical
functions is not adversely affected when
the airplane is exposed to high intensity
radiated fields.
b. For the purposes of this special
condition, the following definition
applies:
Critical Functions: Functions whose
failure would contribute to or cause a
failure condition that would prevent the
continued safe flight and landing of the
airplane.
Issued in Renton, Washington, on October
10, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 06–8762 Filed 10–17–06; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM354; Notice No. 25–06–09–
SC]
Special Conditions: Boeing
Commercial Airplane Group, Boeing
Model 777–200 Series Airplane;
Overhead Cross Aisle Stowage
Compartments
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
rmajette on PROD1PC67 with PROPOSALS
AGENCY:
SUMMARY: The FAA proposes special
conditions for the Boeing Model 777–
200 series airplanes. This airplane,
modified by Boeing Commercial
Airplane Group, will have novel or
unusual design features associated with
overhead cross aisle stowage
compartments. The applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for these design features. These
proposed special conditions contain the
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additional safety standards the
Administrator considers necessary to
establish a level of safety equivalent to
that established by the existing
airworthiness standards.
DATES: We must receive your comments
on or before November 7, 2006.
ADDRESSES: You may mail or deliver
comments on these special conditions
in duplicate to: Federal Aviation
Administration, Transport Airplane
Directorate, Attn: Rules Docket (ANM–
113), Docket No. NM354, 1601 Lind
Avenue, SW., Renton, Washington
98057–3356. You must mark your
comments: Docket No. NM354.
FOR FURTHER INFORMATION CONTACT:
Jayson Claar, FAA, Airframe/Cabin
Branch, ANM–115, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue, SW.,
Renton, Washington 98057–3356;
telephone (425) 227–2194; facsimile
(425) 227–1232.
SUPPLEMENTARY INFORMATION:
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 ask that you send
us two copies of written comments.
We will file in the docket all
comments we receive, as well as a
report summarizing each substantive
public contact with FAA personnel
concerning these special conditions.
You may inspect the docket before and
after the comment closing date. If you
wish to review the docket in person, go
to the address in the ADDRESSES section
of this preamble between 7:30 a.m. and
4 p.m., Monday through Friday, except
Federal holidays.
We will consider all comments we
receive on or before the closing date for
comments. We will consider comments
filed late if it is possible to do so
without incurring expense or delay. We
may change these special conditions
based on the comments we receive.
If you want the FAA to acknowledge
receipt of your comments on these
proposed special conditions, include
with your comments a pre-addressed,
stamped postcard on which the docket
number appears. We will stamp the date
on the postcard and mail it back to you.
Background
On April 20, 2005, Boeing
Commercial Airplane Group, Seattle,
Washington, applied for a supplemental
type certificate to permit installation of
PO 00000
Frm 00006
Fmt 4702
Sfmt 4702
overhead cross aisle stowage
compartments in Boeing 777–200 series
airplanes. The Boeing Model 777–200
series airplanes are large twin engine
airplanes with four pairs of Type A
exits, a passenger capacity of 440, and
a range of 5000 miles. (The Boeing 777–
200 airplanes can be configured with
various passenger capacities and range).
The regulations do not address the
novel and unusual design features
associated with the installation of
overhead cross aisle stowage
compartments installed on the Boeing
Model 777–200, making these special
conditions necessary. Generally, the
requirements for overhead stowage
compartments are similar to stowage
compartments in remote crew rest
compartments (i.e., located on lower
lobe, main deck or overhead) already in
use on Boeing Model 777–200 and –747
series airplanes. Remote crew rest
compartments have been previously
installed and certified in the main
passenger cabin area, above the main
passenger area, and below the passenger
cabin area adjacent to the cargo
compartment of the Boeing Model 777–
200, and –300 series airplanes.
Type Certification Basis
Under the provisions of § 21.101,
Boeing Commercial Airplane Group
must show that the Boeing Model 777–
200, as changed, continues to meet the
applicable provisions of the regulations
incorporated by reference in Type
Certificate No. T00001SE or the
applicable regulations in effect on the
date of application for the change. The
regulations incorporated by reference in
the type certificate are commonly
referred to as the ‘‘original type
certification basis.’’ The regulations
incorporated by reference in Type
Certificate No. T00001SE for the Boeing
Model 777–200 series airplanes include
Title 14 Code of Federal Regulations
(CFR), part 25, as amended by
Amendments 25–1 through 25–82,
except for § 25.571(e)(1) which remains
at Amendment 25–71, with exceptions.
Refer to Type Certificate No. T00001SE,
as applicable, for a complete description
of the certification basis for this model,
including certain special conditions that
are not relevant to these proposed
special conditions.
If the Administrator finds the
applicable airworthiness regulations
(part 25 as amended) do not contain
adequate or appropriate safety standards
for the Boeing Model 777–200 because
of a novel or unusual design feature,
special conditions are prescribed under
the provisions of § 21.16.
In addition to the applicable
airworthiness regulations and special
E:\FR\FM\18OCP1.SGM
18OCP1
Agencies
[Federal Register Volume 71, Number 201 (Wednesday, October 18, 2006)]
[Proposed Rules]
[Pages 61427-61432]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 06-8762]
========================================================================
Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
========================================================================
Federal Register / Vol. 71, No. 201 / Wednesday, October 18, 2006 /
Proposed Rules
[[Page 61427]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM355; Notice No. 25-06-10-SC]
Special Conditions: Dassault Aviation Model Falcon 7X Airplane;
Interaction of Systems and Structures, Limit Pilot Forces, and High
Intensity Radiated Fields (HIRF) Protection
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This action proposes special conditions for the Dassault
Aviation Model Falcon 7X airplane. This airplane will have novel or
unusual design features when compared to the state of technology
envisioned in the airworthiness standards for transport category
airplanes. These design features include interaction of systems and
structures, limit pilot forces, and electrical and electronic flight
control systems. The applicable airworthiness regulations do not
contain adequate or appropriate safety standards for these design
features. 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: We must receive your comments by December 4, 2006.
ADDRESSES: You must mail two copies of your comments to: Federal
Aviation Administration, Transport Airplane Directorate, Attn: Rules
Docket (ANM-113), Docket No. NM355, 1601 Lind Avenue SW., Renton,
Washington, 98057-3356. You may deliver two copies to the Transport
Airplane Directorate at the above address. You must mark your comments:
Docket No. NM355. You can inspect comments in the Rules Docket
weekdays, except Federal holidays, between 7:30 a.m. and 4 p.m.
FOR FURTHER INFORMATION CONTACT: Thomas Rodriguez, FAA, International
Branch, ANM-116, Transport Airplane Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW., Renton, Washington, 98057-3356;
telephone (425) 227-1137; facsimile (425) 227-1149.
SUPPLEMENTARY INFORMATION:
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 ask
that you send us two copies of written comments.
We will file in the docket all comments we receive, as well as a
report summarizing each substantive public contact with FAA personnel
concerning these special conditions. You can inspect the docket before
and after the comment closing date. If you wish to review the docket in
person, go to the address in the ADDRESSES section of this preamble
between 7:30 a.m. and 4 p.m., Monday through Friday, except Federal
holidays.
We will consider all comments we receive on or before the closing
date for comments. We will consider comments filed late if it is
possible to do so without incurring expense or delay. We may change
these special conditions based on the comments we receive.
If you want the FAA to acknowledge receipt of your comments on this
proposal, include with your comments a pre-addressed, stamped postcard
on which the docket number appears. We will stamp the date on the
postcard and mail it back to you.
Background
On June 4, 2002, Dassault Aviation, 9 rond Point des Champs
Elysees, 75008, Paris, France, applied for a type certificate for its
new Model Falcon 7X airplane. The Model Falcon 7X is a 19 passenger
transport category airplane, powered by three aft mounted Pratt &
Whitney PW307A high bypass ratio turbofan engines. The airplane is
operated using a fly-by-wire (FBW) primary flight control system. This
will be the first application of a FBW primary flight control system in
a private/corporate use airplane.
The Dassault Aviation Model Falcon 7X design incorporates equipment
that was not envisioned when part 25 was created. This equipment
affects the interaction of systems and structures, limit pilot forces,
and high intensity radiated fields (HIRF) protection. Therefore,
special conditions are required to provide the level of safety
equivalent to that established by the regulations.
Type Certification Basis
Under the provisions of 14 CFR 21.17, Dassault Aviation must show
that the Model Falcon 7X airplane meets the applicable provisions of
part 25, as amended by Amendments 25-1 through 25-108.
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 Falcon 7X because of a novel
or unusual design feature, special conditions are prescribed under the
provisions of Sec. 21.16.
In addition to the applicable airworthiness regulations and special
conditions, the Model Falcon 7X 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 Sec. 11.19, under
Sec. 11.38, and they become part of the type certification basis under
Sec. 21.17(a)(2).
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.
Novel or Unusual Design Features
The Model Falcon 7X airplane will incorporate three novel or
unusual design features: interaction of systems and structures, limit
pilot forces, and electrical and electronic flight control systems.
These proposed special conditions address equipment which may affect
the airplane's structural performance, either directly or as a
[[Page 61428]]
result of failure or malfunction; pilot limit forces; and electrical
and electronic systems which perform critical functions that may be
vulnerable to HIRF.
These proposed special conditions are identical or nearly identical
to those previously required for type certification of other Dassault
airplane models. In general, the proposed special conditions were
derived initially from standardized requirements developed by the
Aviation Rulemaking Advisory Committee (ARAC), comprised of
representatives of the FAA, Europe's Joint Aviation Authorities (now
replaced by the European Aviation Safety Agency), and industry.
Additional special conditions will be issued for other novel or
unusual design features of the Dassault Model Falcon 7X airplane. These
additional proposed special conditions will pertain to the following
topics:
Dive Speed Definition With Speed Protection System,
Sudden Engine Stoppage,
High Incidence Protection Function,
Side Stick Controllers,
Lateral-Directional and Longitudinal Stability and Low Energy
Awareness,
Flight Envelope Protection: General Limiting Requirements,
Flight Envelope Protection: Normal Load Factor (g) Limiting,
Flight Envelope Protection: Pitch, Roll and High Speed Limiting
Functions,
Flight Control Surface Position Awareness,
Flight Characteristics Compliance via Handling Qualities Rating
Method,
Operation Without Normal Electrical Power.
Proposed special conditions have been issued for the Model Falcon
7X with the novel or unusual design feature pertaining to Pilot
Compartment View-Hydrophobic Coatings in Lieu of Windshield Wipers.
This special condition was published for public comment in the Federal
Register on July 12, 2006 (71 FR 39235).
Discussion
Because of rapid improvements in airplane technology, the
applicable airworthiness regulations do not contain adequate or
appropriate safety standards for these design features. Therefore, in
addition to the requirements of part 25, subparts C and D, the
following three special conditions apply.
Special Condition No. 1. Interaction of Systems and Structures
The Dassault Model Falcon 7X is equipped with systems that may
affect the airplane's structural performance either directly or as a
result of failure or malfunction. The effects of these systems on
structural performance must be considered in the certification
analysis. This analysis must include consideration of normal operation
and of failure conditions with required structural strength levels
related to the probability of occurrence.
Previously, special conditions have been specified to require
consideration of the effects of systems on structures. The special
condition proposed for the Model Falcon 7X is nearly identical to that
issued for other fly-by-wire airplanes.
Special Condition No. 2. Limit Pilot Forces
Like some other certificated transport category airplane models,
the Dassault Model Falcon 7X airplane is equipped with a side stick
controller instead of a conventional wheel or control stick. This kind
of controller is designed to be operated using only one hand. The
requirement of Sec. 25.397(c), which defines limit pilot forces and
torques for conventional wheel or stick controls, is not appropriate
for a side stick controller. Therefore, a special condition is
necessary to specify the appropriate loading conditions for this kind
of controller.
Special Condition No. 3. High Intensity Radiated Fields (HIRF)
Protection
The Dassault Model Falcon X will utilize electrical and electronic
systems which perform critical functions. These systems may be
vulnerable to HIRF external to the airplane. There is no specific
regulation that addresses requirements for protection of electrical and
electronic systems from HIRF. With the trend toward increased power
levels from ground-based transmitters and the advent of space and
satellite communications, coupled with electronic command and control
of the airplane, the immunity of critical avionics/electronics and
electrical systems to HIRF must be established.
To ensure that a level of safety is achieved that is equivalent to
that intended by the regulations incorporated by reference, a special
condition is needed for the Dassault Model Falcon 7X airplane. This
special condition requires that avionics/electronics and electrical
systems that perform critical functions be designed and installed to
preclude component damage and interruption.
It is not possible to precisely define the HIRF to which the
airplane will be exposed in service. There is also uncertainty
concerning the effectiveness of airframe shielding for HIRF.
Furthermore, coupling of electromagnetic energy to cockpit-installed
equipment through the cockpit window apertures is undefined. Based on
surveys and analysis of existing HIRF emitters, adequate protection
from exists when there is compliance with either paragraph 1 or 2
below:
1. A minimum threat of 100 volts rms (root-mean-square) per meter
electric field strength from 10 KHz to 18 GHz.
a. The threat must be applied to the system elements and their
associated wiring harnesses without the benefit of airframe shielding.
b. Demonstration of this level of protection is established through
system tests and analysis.
2. A threat external to the airframe of the field strengths
indicated in the table below for the frequency ranges indicated. Both
peak and average field strength components from the table are to be
demonstrated.
------------------------------------------------------------------------
Field strength
(volts per meter)
Frequency ---------------------
Peak Average
------------------------------------------------------------------------
10 kHz-100 kHz.................................... 50 50
100 kHz-500 kHz................................... 50 50
500 kHz-2 MHz..................................... 50 50
2 MHz-30 MHz...................................... 100 100
30 MHz-70 MHz..................................... 50 50
70 MHz-100 MHz.................................... 50 50
100 MHz-200 MHz................................... 100 100
200 MHz-400 MHz................................... 100 100
400 MHz-700 MHz................................... 700 50
700 MHz-1 GHz..................................... 700 100
1 GHz-2 GHz....................................... 2000 200
2 GHz-4 GHz....................................... 3000 200
4 GHz-6 GHz....................................... 3000 200
6 GHz-8 GHz....................................... 1000 200
8 GHz-12 GHz...................................... 3000 300
12 GHz-18 GHz..................................... 2000 200
18 GHz-40 GHz..................................... 600 200
------------------------------------------------------------------------
The field strengths are expressed in terms of peak of the root-mean-
square (rms) over the complete modulation period.
The threat levels identified above are the result of an FAA review
of existing studies on the subject of HIRF, in light of the ongoing
work of the Electromagnetic Effects Harmonization Working Group of the
Aviation Rulemaking Advisory Committee.
Applicability
As discussed above, these special conditions are applicable to the
Dassault Model Falcon 7X. Should Dassault Aviation 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 certain novel or unusual design features
of the
[[Page 61429]]
Dassault Model Falcon 7X airplane. It is not a rule of general
applicability, and it affects only the applicant which applied to the
FAA for approval of these features on the airplane.
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, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type certification basis for Dassault Aviation Model Falcon 7X
airplanes.
1. Interaction of Systems and Structures
In addition to the requirements of part 25, subparts C and D, the
following proposed special conditions would apply:
a. For airplanes equipped with systems that affect structural
performance--either directly or as a result of a failure or
malfunction--the influence of these systems and their failure
conditions must be taken into account when showing compliance with the
requirements of part 25, subparts C and D. Paragraph c below must be
used to evaluate the structural performance of airplanes equipped with
these systems.
b. Unless shown to be extremely improbable, the airplane must be
designed to withstand any forced structural vibration resulting from
any failure, malfunction, or adverse condition in the flight control
system. These loads must be treated in accordance with the requirements
of paragraph a above.
c. Interaction of Systems and Structures.
(1) General: The following criteria must be used for showing
compliance with this special condition for interaction of systems and
structures and with Sec. 25.629 for airplanes equipped with flight
control systems, autopilots, stability augmentation systems, load
alleviation systems, flutter control systems, and fuel management
systems. If this special condition is used for other systems, it may be
necessary to adapt the criteria to the specific system.
(a) The criteria defined herein address only the direct structural
consequences of the system responses and performances. They cannot be
considered in isolation but should be included in the overall safety
evaluation of the airplane. These criteria may, in some instances,
duplicate standards already established for this evaluation. These
criteria are applicable only to structures whose failure could prevent
continued safe flight and landing. Specific criteria that define
acceptable limits on handling characteristics or stability requirements
when operating in the system degraded or inoperative modes are not
provided in this special condition.
(b) Depending upon the specific characteristics of the airplane,
additional studies may be required that go beyond the criteria provided
in this special condition in order to demonstrate the capability of the
airplane to meet other realistic conditions, such as alternative gust
or maneuver descriptions for an airplane equipped with a load
alleviation system.
(c) The following definitions are applicable to this paragraph.
Structural performance: Capability of the airplane to meet the
structural requirements of part 25.
Flight limitations: Limitations that can be applied to the airplane
flight conditions following an in-flight occurrence and that are
included in the flight manual (e.g., speed limitations and avoidance of
severe weather conditions).
Operational limitations: Limitations, including flight limitations,
that can be applied to the airplane operating conditions before
dispatch (e.g., fuel, payload, and Master Minimum Equipment List
limitations).
Probabilistic terms: The probabilistic terms (probable, improbable,
and extremely improbable) used in this Special Conditions are the same
as those used in Sec. 25.1309.
Failure condition: The term failure condition is the same as that
used in Sec. 25.1309. However, this Special Conditions applies only to
system failure conditions that affect the structural performance of the
airplane (e.g., system failure conditions that induce loads, change the
response of the airplane to inputs such as gusts or pilot actions, or
lower flutter margins).
(2) Effects of Systems on Structures.
(a) General. The following criteria will be used in determining the
influence of a system and its failure conditions on the airplane
structure.
(b) System fully operative. With the system fully operative, the
following apply:
(1) Limit loads must be derived in all normal operating
configurations of the system from all the limit conditions specified in
subpart C (or used in lieu of those specified in subpart C), taking
into account any special behavior of such a system or associated
functions or any effect on the structural performance of the airplane
that may occur up to the limit loads. In particular, any significant
non-linearity (rate of displacement of control surface, thresholds or
any other system non-linearities) must be accounted for in a realistic
or conservative way when deriving limit loads from limit conditions.
(2) The airplane must meet the strength requirements of part 25
(static strength, residual strength), using the specified factors to
derive ultimate loads from the limit loads defined above. The effect of
non-linearities must be investigated beyond limit conditions to ensure
that the behavior of the system presents no anomaly compared to the
behavior below limit conditions. However, conditions beyond limit
conditions need not be considered, when it can be shown that the
airplane has design features that will not allow it to exceed those
limit conditions.
(3) The airplane must meet the aeroelastic stability requirements
of Sec. 25.629.
(c) System in the failure condition. For any system failure
condition not shown to be extremely improbable, the following apply:
(1) At the time of occurrence. Starting from 1g level flight
conditions, a realistic scenario, including pilot corrective actions,
must be established to determine the loads occurring at the time of
failure and immediately after failure.
(i) For static strength substantiation, these loads multiplied by
an appropriate factor of safety that is related to the probability of
occurrence of the failure are ultimate loads to be considered for
design. The factor of safety (FS) is defined in Figure 1.
[[Page 61430]]
[GRAPHIC] [TIFF OMITTED] TP18OC06.008
(ii) For residual strength substantiation, the airplane must be
able to withstand two thirds of the ultimate loads defined in paragraph
(c)(1)(i) of this section. For pressurized cabins, these loads must be
combined with the normal operating differential pressure.
(iii) Freedom from aeroelastic instability must be shown up to the
speeds defined in Sec. 25.629(b)(2). For failure conditions that
result in speed increases beyond VC/MC, freedom
from aeroelastic instability must be shown to increased speeds, so that
the margins intended by Sec. 25.629(b)(2) are maintained.
(iv) Failures of the system that result in forced structural
vibrations (oscillatory failures) must not produce loads that could
result in detrimental deformation of primary structure.
(2) For the continuation of the flight. For the airplane in the
system failed state and considering any appropriate reconfiguration and
flight limitations, the following apply:
(i) The loads derived from the following conditions (or used in
lieu of the following conditions) at speeds up to VC/
MC or the speed limitation prescribed for the remainder of
the flight must be determined:
(A) the limit symmetrical maneuvering conditions specified in
Sec. Sec. 25.331 and in 25.345.
(B) the limit gust and turbulence conditions specified in
Sec. Sec. 25.341 and in 25.345.
(C) the limit rolling conditions specified in Sec. 25.349 and the
limit unsymmetrical conditions specified in Sec. Sec. 25.367 and
25.427(b) and (c).
(D) the limit yaw maneuvering conditions specified in Sec. 25.351.
(E) the limit ground loading conditions specified in Sec. Sec.
25.473 and 25.491.
(ii) For static strength substantiation, each part of the structure
must be able to withstand the loads in paragraph (c)(2)(i) of this
special condition multiplied by a factor of safety, depending on the
probability of being in this failure state. The factor of safety is
defined in Figure 2.
[GRAPHIC] [TIFF OMITTED] TP18OC06.009
[[Page 61431]]
Qj = (Tj)(Pj)
Where:
Tj = Average time spent in failure condition j (in hours)
Pj = Probability of occurrence of failure mode j (per
hour)
Note: If Pj is greater than 10-\3\ per
flight hour, then a 1.5 factor of safety must be applied to all
limit load conditions specified in subpart C.
(iii) For residual strength substantiation, the airplane must be
able to withstand two thirds of the ultimate loads defined in paragraph
(c)(2)(ii). For pressurized cabins, these loads must be combined with
the normal operating differential pressure.
(iv) If the loads induced by the failure condition have a
significant effect on fatigue or damage tolerance, then their effects
must be taken into account.
(v) Freedom from aeroelastic instability must be shown up to a
speed determined from Figure 3. Flutter clearance speeds V' and V'' may
be based on the speed limitation specified for the remainder of the
flight, using the margins defined by Sec. 25.629(b).
[GRAPHIC] [TIFF OMITTED] TP18OC06.010
V' = Clearance speed as defined by Sec. 25.629(b)(2).
V'' = Clearance speed as defined by Sec. 25.629(b)(1).
Qj = (Tj)(Pj)
Where:
Tj = Average time spent in failure condition j (in hours)
Pj = Probability of occurrence of failure mode j (per
hour)
Note: If Pj is greater than 10-\3\ per
flight hour, then the flutter clearance speed must not be less than
V''.
(vi) Freedom from aeroelastic instability must also be shown up to
V' in Figure 3 above for any probable system failure condition combined
with any damage required or selected for investigation by Sec.
25.571(b).
(3) Consideration of certain failure conditions may be required by
other sections of this Part, regardless of calculated system
reliability. Where analysis shows the probability of these failure
conditions to be less than 10-\9\, criteria other than those
specified in this paragraph may be used for structural substantiation
to show continued safe flight and landing.
(d) Warning considerations. For system failure detection and
warning, the following apply:
(1) The system must be checked for failure conditions, not
extremely improbable, that degrade the structural capability below the
level required by part 25 or significantly reduce the reliability of
the remaining system. As far as reasonably practicable, the flightcrew
must be made aware of these failures before flight. Certain elements of
the control system, such as mechanical and hydraulic components, may
use special periodic inspections, and electronic components may use
daily checks in lieu of warning systems to achieve the objective of
this requirement. These certification maintenance requirements must be
limited to components that are not readily detectable by normal warning
systems and where service history shows that inspections will provide
an adequate level of safety.
(2) The existence of any failure condition, not extremely
improbable, during flight that could significantly affect the
structural capability of the airplane and for which the associated
reduction in airworthiness can be minimized by suitable flight
limitations must be signaled to the flightcrew. For example, failure
conditions that result in a factor of safety between the airplane
strength and the loads of part 25, subpart C, below 1.25 or flutter
margins below V'' must be signaled to the crew during flight.
(e) Dispatch with known failure conditions. If the airplane is to
be dispatched in a known system failure condition that affects
structural performance or affects the reliability of the remaining
system to maintain structural performance, then the provisions of these
Special Conditions must be met, including the provisions of paragraph
(b), for the dispatched condition and paragraph (c) for subsequent
failures. Expected operational limitations may be taken into account in
establishing Pj as the probability of failure occurrence for
determining the safety margin in Figure 1. Flight limitations and
expected operational limitations may be taken into account in
establishing Qj as the combined probability of being in the dispatched
failure condition and the subsequent failure condition for the safety
margins in Figures 2 and 3. These limitations must be such that the
probability of being in this combined failure state and then
subsequently encountering limit load conditions is extremely
improbable. No reduction in these safety margins is allowed if the
subsequent system failure rate is greater than 1E-3 per flight hour.
2. Limit Pilot Forces
In addition to the requirements of Sec. 25.397(c) the following
special condition applies.
The limit pilot forces are:
a. For all components between and including the handle and its
control stops.
------------------------------------------------------------------------
Pitch Roll
------------------------------------------------------------------------
Nose up 200 lbf (pounds force)............ Nose left 100 lbf.
Nose down 200 lbf Nose right 100 lbf.
------------------------------------------------------------------------
b. For all other components of the side stick control assembly, but
[[Page 61432]]
excluding the internal components of the electrical sensor assemblies
to avoid damage as a result of an in-flight jam.
------------------------------------------------------------------------
Pitch Roll
------------------------------------------------------------------------
Nose up 125 lbf........................... Nose left 50 lbf.
Nose down 125 lbf......................... Nose right 50 lbf.
------------------------------------------------------------------------
3. High Intensity Radiated Fields (HIRF) Protection
a. Protection from Unwanted Effects of High Intensity Radiated
Fields. Each electrical and electronic system which performs critical
functions must be designed and installed to ensure that the operation
and operational capability of these systems to perform critical
functions is not adversely affected when the airplane is exposed to
high intensity radiated fields.
b. For the purposes of this special condition, the following
definition applies:
Critical Functions: Functions whose failure would contribute to or
cause a failure condition that would prevent the continued safe flight
and landing of the airplane.
Issued in Renton, Washington, on October 10, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 06-8762 Filed 10-17-06; 8:45 am]
BILLING CODE 4910-13-P