Special Conditions: Gulfstream Model GVII-G500 Airplanes, Automatic Speed Protection for Design Dive Speed, 60028-60030 [2015-25275]
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60028
Federal Register / Vol. 80, No. 192 / Monday, October 5, 2015 / Rules and Regulations
• General ergonomics: Armrest
comfort and support, local freedom of
movement, displacement-angle
suitability, and axis harmony.
• Inadvertent pilot input in
turbulence.
• Inadvertent pitch and roll crosstalk
from pilot inputs on the side-stick
controller.
Discussion of Comments
Notice of proposed special conditions
no. 25–15–07–SC for the Gulfstream
Model GVII–G500 airplane was
published in the Federal Register on
August 18, 2015 [80 FR 49934]. No
comments were received, and the
special conditions are adopted as
proposed.
Applicability
As discussed above, these special
conditions apply to Gulfstream Model
GVII–G500 airplanes. Should
Gulfstream apply later for a change to
the type certificate to include another
model incorporating the same or similar
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
Gulfstream Model GVII–G500 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:
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Jkt 238001
[FR Doc. 2015–25276 Filed 10–2–15; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2015–1482; Special
Conditions No. 25–600–SC]
Special Conditions: Gulfstream Model
GVII–G500 Airplanes, Automatic Speed
Protection for Design Dive Speed
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions.
The Special Conditions
■ Accordingly, pursuant to the authority
delegated to me by the Administrator,
the following special conditions are
issued as part of the type certification
basis for the Gulfstream Model GVII–
G500 airplane, in lieu of §§ 25.143(d),
25.143(i)(2), 25.145(b), 25.173(c),
25.175(b), and 25.175(d):
Pilot strength: In lieu of the controlforce limits shown in § 25.143(d) for
pitch and roll, and in lieu of specific
pitch-force requirements of
§§ 25.143(i)(2), 25.145(b), 25.173(c),
25.175(b), and 25.175(d), Gulfstream
must show that the temporary and
maximum prolonged-force levels for the
side-stick controllers are suitable for all
expected operating conditions and
configurations, whether normal or nonnormal.
Pilot-control authority: The electronic
side-stick-controller coupling design
must provide for corrective and
16:55 Oct 02, 2015
Issued in Renton, Washington, September
25, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
AGENCY:
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
VerDate Sep<11>2014
overriding control inputs by either pilot
with no unsafe characteristics.
Annunciation of the controller status
must be provided, and must not be
confusing to the flightcrew.
Pilot control: Gulfstream must show
by flight tests that the use of side-stick
controllers does not produce unsuitable
pilot-in-the-loop control characteristics
when considering precision path control
and tasks, and turbulence. In addition,
pitch and roll control force and
displacement sensitivity must be
compatible, so that normal pilot inputs
on one control axis will not cause
significant unintentional inputs
(crossover) on the other.
These special conditions are
issued for the Gulfstream Model GVII–
G500 airplane. This airplane will have
a novel or unusual design feature when
compared to the state of technology
envisioned in the airworthiness
standards for transport-category
airplanes.
This design feature is associated with
a reduced margin between design
cruising speed, VC/MC, and design
diving speed, VD/MD, based on the
incorporation of a high-speed protection
system that limits nose-down pilot
authority at speeds above VC/MC. The
applicable airworthiness regulations do
not contain adequate or appropriate
safety standards for this design feature.
These special conditions contain the
additional safety standards that the
Administrator considers necessary to
establish a level of safety equivalent to
that established by the existing
airworthiness standards.
DATES: Effective November 4, 2015.
FOR FURTHER INFORMATION CONTACT: Walt
Sippel, FAA, Airframe and Cabin Safety
SUMMARY:
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Branch, ANM–115, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98057–3356;
telephone 425–227–2774; facsimile
425–227–1232.
SUPPLEMENTARY INFORMATION:
Background
On March 29, 2012, Gulfstream
Aerospace Corporation applied for a
type certificate for their new Model
GVII–G500 airplane. The Model GVII–
G500 airplane will be a large-cabin
business jet with seating for 19
passengers. It will incorporate a low,
swept-wing design with winglets and a
T-tail. The powerplant will consist of
two aft-fuselage-mounted Pratt &
Whitney turbofan engines.
The Model GVII–G500 will have a
wingspan of approximately 87 feet and
a length of just over 91 feet. Maximum
takeoff weight will be approximately
76,850 pounds and maximum takeoff
thrust will be approximately 15,135
pounds. Maximum range will be
approximately 5,000 nautical miles, and
maximum operating altitude will be
51,000 feet.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.17,
Gulfstream must show that the Model
GVII–G500 airplane meets the
applicable provisions of part 25 as
amended by Amendments 25–1 through
25–137.
In addition, the certification basis
includes other regulations, special
conditions, and exemptions that are not
relevant to these special conditions.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 25) do not contain
adequate or appropriate safety standards
for Model GVII–G500 airplanes because
of a novel or unusual design feature,
special conditions are prescribed under
the provisions of § 21.16.
Special conditions are initially
applicable to the model for which they
are issued. Should the type certificate
for that model be amended later to
include any other model that
incorporates the same novel or unusual
design feature, the special conditions
would also apply to the other model
under § 21.101.
In addition to the applicable
airworthiness regulations and special
conditions, the Model GVII–G500
airplane must comply with the fuel-vent
and exhaust-emission requirements of
14 CFR part 34, and the noisecertification requirements of 14 CFR
part 36; and the FAA must issue a
finding of regulatory adequacy under
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Federal Register / Vol. 80, No. 192 / Monday, October 5, 2015 / Rules and Regulations
§ 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).
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Novel or Unusual Design Features
The Gulfstream Model GVII–G500
airplane will incorporate the following
novel or unusual design feature:
For this airplane, Gulfstream will
reduce the margin between VC/MC and
VD/MD, required by 14 CFR 25.335(b),
based on the incorporation of a highspeed protection system in the
airplane’s flight-control laws. The highspeed protection system limits nosedown pilot authority at speeds above
VC/MC, and prevents the airplane from
performing the maneuver required
under § 25.335(b)(1).
Discussion
Title 14, Code of Federal Regulations
(14 CFR) 25.335(b)(1) is an analytical
envelope condition which was
originally adopted in Part 4b of the Civil
Air Regulations to provide an acceptable
speed margin between design cruise
speed and design dive speed. Flutter
clearance design speeds and airframe
design loads are impacted by the design
dive speed. While the initial condition
for the upset specified in the rule is 1g
level flight, protection is afforded for
other inadvertent overspeed conditions
as well. Section 25.335(b)(1) is intended
as a conservative enveloping condition
for potential overspeed conditions,
including non-symmetric ones. To
establish that potential overspeed
conditions are enveloped, Gulfstream
must demonstrate that any reduced
speed margin based on the high-speed
protection system in the Model GVII–
G500 airplane will not be exceeded in
inadvertent or gust-induced upsets
resulting in initiation of the dive from
non-symmetric attitudes; or that the
airplane is protected by the flightcontrol laws from getting into nonsymmetric upset conditions. Gulfstream
must conduct a demonstration that
includes a comprehensive set of
conditions as described below.
These special conditions are in lieu of
§ 25.335(b)(1). Section 25.335(b)(2),
which also addresses the design dive
speed, is applied separately (Advisory
Circular (AC) 25.335–1A provides an
acceptable means of compliance to
§ 25.335(b)(2)).
Special conditions are necessary to
address the Model GVII–G500 airplane
high-speed protection system. These
special conditions identify various
symmetric and non-symmetric
VerDate Sep<11>2014
16:55 Oct 02, 2015
Jkt 238001
maneuvers that will ensure that an
appropriate design dive speed, VD/MD,
is established.
Special Condition 2 of these special
conditions references AC 25–7C, section
8, paragraph 32, ‘‘Gust Upset,’’ included
here for reference:
In the following three upset tests, the
values of displacement should be
appropriate to the airplane type and
should depend upon airplane stability
and inertia characteristics. The lower
and upper limits should be used for
airplanes with low and high
maneuverability, respectively.
(i) With the airplane trimmed in
wings-level flight, simulate a transient
gust by rapidly rolling to the maximum
bank angle appropriate for the airplane,
but not less than 45 degrees nor more
than 60 degrees. The rudder and
longitudinal control should be held
fixed during the time that the required
bank is being attained. The rolling
velocity should be arrested at this bank
angle. Following this, the controls
should be abandoned for a minimum of
3 seconds after VMO/MMO, or after 10
seconds, whichever occurs first.
(ii) Perform a longitudinal upset from
normal cruise. Airplane trim is
determined at VMO/MMO using power
and thrust required for level flight, but
with not more than maximum
continuous power and thrust. This is
followed by a decrease in speed, after
which an attitude of 6 to l2 degrees nose
down, as appropriate for the airplane
type, is attained with the power, thrust,
and trim initially required for VMO/MMO
in level flight. The airplane is permitted
to accelerate until 3 seconds after VMO/
MMO. The force limits of § 25.143(d) for
short term application apply.
(iii) Perform a two-axis upset,
consisting of combined longitudinal and
lateral upsets. Perform the longitudinal
upset, as in paragraph (ii) above, and
when the pitch attitude is set, but before
reaching VMO/MMO, roll the airplane to
between 15 and 25 degrees. The
established attitude should be
maintained until 3 seconds after VMO/
MMO.
Special Conditions 3 and 4 of these
special conditions indicate that failures
of the high-speed protection system
must be improbable and must be
annunciated to the pilots. If these two
criteria are not met, then the probability
that the established dive speed will be
exceeded, and the resulting risk to the
airplane, are too great. On the other
hand, if the high-speed protection
system is known to be inoperative, then
dispatch of the airplane may be
acceptable as allowed by Special
Condition 5 of these special conditions.
Dispatch would only be acceptable if
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60029
appropriate reduced operating speeds,
VMO/MMO, as well as the overspeed
warning for exceeding those speeds, are
provided in both the airplane flight
manual and on the flightdeck display,
and are equivalent to that of the normal
airplane with the high-speed protection
system operative.
We do not believe that application of
the ‘‘Interaction of Systems and
Structures’’ Special Conditions
(reference GVI Issue Paper A–2), or
EASA Certification Specification
25.302, are appropriate in this case,
because design dive speed is, in and of
itself, part of the design criteria.
Stability and control, flight loads, and
flutter evaluations all depend on the
design dive speed. Therefore, a single
design dive speed should be established
that will not be exceeded, taking into
account the performance of the highspeed protection system as well as its
failure modes, failure indications, and
accompanying flight-manual
instructions.
These special conditions contain the
additional safety standards that the
Administrator considers necessary to
establish a level of safety equivalent to
that established by the existing
airworthiness standards.
Discussion of Comments
Notice of proposed special conditions
no. 25–15–08–SC for the Gulfstream
Model GVII–G500 airplane was
published in the Federal Register on
August 18, 2015 [80 FR 49936]. No
comments were received, and the
special conditions are adopted as
proposed.
Applicability
As discussed above, these special
conditions are applicable to the
Gulfstream Model GVII–G500 airplane.
Should Gulfstream apply at a later date
for a change to the type certificate to
include another model incorporating the
same novel or unusual design feature,
the special conditions would apply to
that model as well.
Conclusion
This action affects only certain novel
or unusual design features on one model
of airplane. It is not a rule of general
applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for these
special conditions is as follows:
■
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
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60030
Federal Register / Vol. 80, No. 192 / Monday, October 5, 2015 / Rules and Regulations
The Special Conditions
Accordingly, pursuant to the authority
delegated to me by the Administrator,
the following special conditions are
issued as part of the type certification
basis for Gulfstream Model GVII–G500
airplanes.
1. In lieu of compliance with
§ 25.335(b)(1), if the flight-control
system includes functions that act
automatically to initiate recovery before
the end of the 20-second period
specified in § 25.335(b)(1), VD/MD must
be determined from the greater of the
speeds resulting from conditions (a) and
(b) of these special conditions. The
speed increase occurring in these
maneuvers may be calculated if reliable
or conservative aerodynamic data are
used.
(a) From an initial condition of
stabilized flight at VC/MC, the airplane
is upset so as to take up a new flight
path 7.5 degrees below the initial path.
Control application, up to full authority,
is made to try to maintain this new
flight path. Twenty seconds after
initiating the upset, manual recovery is
made at a load factor of 1.5g (0.5
acceleration increment), or such greater
load factor that is automatically applied
by the system with the pilot’s pitch
control neutral. Power, as specified in
§ 25.175(b)(1)(iv), is assumed until
recovery is initiated, at which time
power reduction, and the use of pilotcontrolled drag devices, may be used.
(b) From a speed below VC/MC, with
power to maintain stabilized level flight
at this speed, the airplane is upset so as
to accelerate through VC/MC at a flight
path 15 degrees below the initial path
(or at the steepest nose-down attitude
that the system will permit with full
control authority if less than 15
degrees). The pilot’s controls may be in
the neutral position after reaching VC/
MC and before recovery is initiated.
Recovery may be initiated 3 seconds
after operation of the high-speed
warning system by application of a load
of 1.5g (0.5 acceleration increment), or
such greater load factor that is
automatically applied by the system
with the pilot’s pitch control neutral.
Power may be reduced simultaneously.
All other means of decelerating the
airplane, the use of which is authorized
up to the highest speed reached in the
maneuver, may be used. The interval
between successive pilot actions must
not be less than 1 second.
2. The applicant must also
demonstrate that the speed margin,
established as above, will not be
exceeded in inadvertent or gust-induced
upsets resulting in initiation of the dive
from non-symmetric attitudes, unless
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■
VerDate Sep<11>2014
16:55 Oct 02, 2015
Jkt 238001
the airplane is protected by the flightcontrol laws from getting into nonsymmetric upset conditions. The upset
maneuvers described in Advisory
Circular 25–7C, ‘‘Flight Test Guide for
Certification of Transport Category
Airplanes,’’ section 8, paragraph 32,
sub-paragraphs c(3)(a), (b), and (c), may
be used to comply with this
requirement.
3. The probability of any failure of the
high-speed protection system, which
would result in an airspeed exceeding
those determined by Special Conditions
1 and 2, must be less than 10¥5 per
flight hour.
4. Failures of the system must be
annunciated to the pilots. Flight manual
instructions must be provided that
reduce the maximum operating speeds,
VMO/MMO. With the system failed, the
operating speed must be reduced to a
value that maintains a speed margin
between VMO/MMO and VD/MD, and that
is consistent with showing compliance
with § 25.335(b) without the benefit of
the high-speed protection system.
5. The applicant may request that the
Master Minimum Equipment List relief
for the high-speed protection system be
considered by the FAA Flight
Operations Evaluation Board, provided
that the flight manual instructions
indicate reduced maximum operating
speeds as described in Special
Condition 4. In addition, the flightdeck
display of the reduced operating speeds,
as well as the overspeed warning for
exceeding those speeds, must be
equivalent to that of the normal airplane
with the high-speed protection system
operative. Also, the applicant must
show that no additional hazards are
introduced with the high-speed
protection system inoperative.
Issued in Renton, Washington, September
25, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 2015–25275 Filed 10–2–15; 8:45 am]
BILLING CODE 4910–13–P
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2015–3877; Directorate
Identifier 2015–SW–039–AD; Amendment
39–18284; AD 2015–18–51]
RIN 2120–AA64
Airworthiness Directives; Airbus
Helicopters
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule; request for
comments.
AGENCY:
We are publishing a new
airworthiness directive (AD) for Airbus
Helicopters Model AS332C, AS332C1,
AS332L, and AS332L1 helicopters,
which was sent previously to all known
U.S. owners and operators of these
helicopters. This AD requires inspecting
certain tail rotor (T/R) blades, replacing
the set of T/R blades if there is damage,
deactivating the rotor de-icing system,
revising the rotorcraft flight manual
(RFM), and installing a placard. This AD
is prompted by a report of a T/R deicing system power supply box stuck in
a ‘‘closed’’ position providing an
uncontrolled and un-annunciated power
supply to the system. These actions are
intended to detect and prevent
structural damage to the T/R blades
caused by overheating, and subsequent
loss of control of the helicopter.
DATES: This AD becomes effective
October 20, 2015 to all persons except
those persons to whom it was made
immediately effective by Emergency AD
2015–18–51, issued on September 11,
2015, which contains the requirements
of this AD.
We must receive comments on this
AD by December 4, 2015.
ADDRESSES: You may send comments by
any of the following methods:
• Federal eRulemaking Docket: Go to
https://www.regulations.gov. Follow the
online instructions for sending your
comments electronically.
• Fax: 202–493–2251.
• Mail: Send comments to the U.S.
Department of Transportation, Docket
Operations, M–30, West Building
Ground Floor, Room W12–140, 1200
New Jersey Avenue SE., Washington,
DC 20590–0001.
• Hand Delivery: Deliver to the
‘‘Mail’’ address between 9 a.m. and
5 p.m., Monday through Friday, except
Federal holidays.
SUMMARY:
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]]>Agencies
[Federal Register Volume 80, Number 192 (Monday, October 5, 2015)]
[Rules and Regulations]
[Pages 60028-60030]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-25275]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2015-1482; Special Conditions No. 25-600-SC]
Special Conditions: Gulfstream Model GVII-G500 Airplanes,
Automatic Speed Protection for Design Dive Speed
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Gulfstream Model
GVII-G500 airplane. This airplane will have a novel or unusual design
feature when compared to the state of technology envisioned in the
airworthiness standards for transport-category airplanes.
This design feature is associated with a reduced margin between
design cruising speed, VC/MC, and design diving
speed, VD/MD, based on the incorporation of a
high-speed protection system that limits nose-down pilot authority at
speeds above VC/MC. The applicable airworthiness
regulations do not contain adequate or appropriate safety standards for
this design feature. These special conditions contain the additional
safety standards that the Administrator considers necessary to
establish a level of safety equivalent to that established by the
existing airworthiness standards.
DATES: Effective November 4, 2015.
FOR FURTHER INFORMATION CONTACT: Walt Sippel, FAA, Airframe and Cabin
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-2774; facsimile 425-227-1232.
SUPPLEMENTARY INFORMATION:
Background
On March 29, 2012, Gulfstream Aerospace Corporation applied for a
type certificate for their new Model GVII-G500 airplane. The Model
GVII-G500 airplane will be a large-cabin business jet with seating for
19 passengers. It will incorporate a low, swept-wing design with
winglets and a T-tail. The powerplant will consist of two aft-fuselage-
mounted Pratt & Whitney turbofan engines.
The Model GVII-G500 will have a wingspan of approximately 87 feet
and a length of just over 91 feet. Maximum takeoff weight will be
approximately 76,850 pounds and maximum takeoff thrust will be
approximately 15,135 pounds. Maximum range will be approximately 5,000
nautical miles, and maximum operating altitude will be 51,000 feet.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.17, Gulfstream must show that the Model GVII-G500 airplane
meets the applicable provisions of part 25 as amended by Amendments 25-
1 through 25-137.
In addition, the certification basis includes other regulations,
special conditions, and exemptions that are not relevant to these
special conditions.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 25) do not contain adequate or
appropriate safety standards for Model GVII-G500 airplanes because of a
novel or unusual design feature, special conditions are prescribed
under the provisions of Sec. 21.16.
Special conditions are initially applicable to the model for which
they are issued. Should the type certificate for that model be amended
later to include any other model that incorporates the same novel or
unusual design feature, 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 Model GVII-G500 airplane must comply with the fuel-vent
and exhaust-emission requirements of 14 CFR part 34, and the noise-
certification requirements of 14 CFR part 36; and the FAA must issue a
finding of regulatory adequacy under
[[Page 60029]]
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 Gulfstream Model GVII-G500 airplane will incorporate the
following novel or unusual design feature:
For this airplane, Gulfstream will reduce the margin between
VC/MC and VD/MD, required
by 14 CFR 25.335(b), based on the incorporation of a high-speed
protection system in the airplane's flight-control laws. The high-speed
protection system limits nose-down pilot authority at speeds above
VC/MC, and prevents the airplane from performing
the maneuver required under Sec. 25.335(b)(1).
Discussion
Title 14, Code of Federal Regulations (14 CFR) 25.335(b)(1) is an
analytical envelope condition which was originally adopted in Part 4b
of the Civil Air Regulations to provide an acceptable speed margin
between design cruise speed and design dive speed. Flutter clearance
design speeds and airframe design loads are impacted by the design dive
speed. While the initial condition for the upset specified in the rule
is 1g level flight, protection is afforded for other inadvertent
overspeed conditions as well. Section 25.335(b)(1) is intended as a
conservative enveloping condition for potential overspeed conditions,
including non-symmetric ones. To establish that potential overspeed
conditions are enveloped, Gulfstream must demonstrate that any reduced
speed margin based on the high-speed protection system in the Model
GVII-G500 airplane will not be exceeded in inadvertent or gust-induced
upsets resulting in initiation of the dive from non-symmetric
attitudes; or that the airplane is protected by the flight-control laws
from getting into non-symmetric upset conditions. Gulfstream must
conduct a demonstration that includes a comprehensive set of conditions
as described below.
These special conditions are in lieu of Sec. 25.335(b)(1). Section
25.335(b)(2), which also addresses the design dive speed, is applied
separately (Advisory Circular (AC) 25.335-1A provides an acceptable
means of compliance to Sec. 25.335(b)(2)).
Special conditions are necessary to address the Model GVII-G500
airplane high-speed protection system. These special conditions
identify various symmetric and non-symmetric maneuvers that will ensure
that an appropriate design dive speed, VD/MD, is
established.
Special Condition 2 of these special conditions references AC 25-
7C, section 8, paragraph 32, ``Gust Upset,'' included here for
reference:
In the following three upset tests, the values of displacement
should be appropriate to the airplane type and should depend upon
airplane stability and inertia characteristics. The lower and upper
limits should be used for airplanes with low and high maneuverability,
respectively.
(i) With the airplane trimmed in wings-level flight, simulate a
transient gust by rapidly rolling to the maximum bank angle appropriate
for the airplane, but not less than 45 degrees nor more than 60
degrees. The rudder and longitudinal control should be held fixed
during the time that the required bank is being attained. The rolling
velocity should be arrested at this bank angle. Following this, the
controls should be abandoned for a minimum of 3 seconds after
VMO/MMO, or after 10 seconds, whichever occurs
first.
(ii) Perform a longitudinal upset from normal cruise. Airplane trim
is determined at VMO/MMO using power and thrust
required for level flight, but with not more than maximum continuous
power and thrust. This is followed by a decrease in speed, after which
an attitude of 6 to l2 degrees nose down, as appropriate for the
airplane type, is attained with the power, thrust, and trim initially
required for VMO/MMO in level flight. The
airplane is permitted to accelerate until 3 seconds after
VMO/MMO. The force limits of Sec. 25.143(d) for
short term application apply.
(iii) Perform a two-axis upset, consisting of combined longitudinal
and lateral upsets. Perform the longitudinal upset, as in paragraph
(ii) above, and when the pitch attitude is set, but before reaching
VMO/MMO, roll the airplane to between 15 and 25
degrees. The established attitude should be maintained until 3 seconds
after VMO/MMO.
Special Conditions 3 and 4 of these special conditions indicate
that failures of the high-speed protection system must be improbable
and must be annunciated to the pilots. If these two criteria are not
met, then the probability that the established dive speed will be
exceeded, and the resulting risk to the airplane, are too great. On the
other hand, if the high-speed protection system is known to be
inoperative, then dispatch of the airplane may be acceptable as allowed
by Special Condition 5 of these special conditions. Dispatch would only
be acceptable if appropriate reduced operating speeds, VMO/
MMO, as well as the overspeed warning for exceeding those
speeds, are provided in both the airplane flight manual and on the
flightdeck display, and are equivalent to that of the normal airplane
with the high-speed protection system operative.
We do not believe that application of the ``Interaction of Systems
and Structures'' Special Conditions (reference GVI Issue Paper A-2), or
EASA Certification Specification 25.302, are appropriate in this case,
because design dive speed is, in and of itself, part of the design
criteria. Stability and control, flight loads, and flutter evaluations
all depend on the design dive speed. Therefore, a single design dive
speed should be established that will not be exceeded, taking into
account the performance of the high-speed protection system as well as
its failure modes, failure indications, and accompanying flight-manual
instructions.
These special conditions contain the additional safety standards
that the Administrator considers necessary to establish a level of
safety equivalent to that established by the existing airworthiness
standards.
Discussion of Comments
Notice of proposed special conditions no. 25-15-08-SC for the
Gulfstream Model GVII-G500 airplane was published in the Federal
Register on August 18, 2015 [80 FR 49936]. No comments were received,
and the special conditions are adopted as proposed.
Applicability
As discussed above, these special conditions are applicable to the
Gulfstream Model GVII-G500 airplane. Should Gulfstream apply at a later
date for a change to the type certificate to include another model
incorporating the same novel or unusual design feature, the special
conditions would apply to that model as well.
Conclusion
This action affects only certain novel or unusual design features
on one model of airplane. It is not a rule of general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
0
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
[[Page 60030]]
The Special Conditions
0
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 Gulfstream Model GVII-G500 airplanes.
1. In lieu of compliance with Sec. 25.335(b)(1), if the flight-
control system includes functions that act automatically to initiate
recovery before the end of the 20-second period specified in Sec.
25.335(b)(1), VD/MD must be determined from the
greater of the speeds resulting from conditions (a) and (b) of these
special conditions. The speed increase occurring in these maneuvers may
be calculated if reliable or conservative aerodynamic data are used.
(a) From an initial condition of stabilized flight at
VC/MC, the airplane is upset so as to take up a
new flight path 7.5 degrees below the initial path. Control
application, up to full authority, is made to try to maintain this new
flight path. Twenty seconds after initiating the upset, manual recovery
is made at a load factor of 1.5g (0.5 acceleration increment), or such
greater load factor that is automatically applied by the system with
the pilot's pitch control neutral. Power, as specified in Sec.
25.175(b)(1)(iv), is assumed until recovery is initiated, at which time
power reduction, and the use of pilot-controlled drag devices, may be
used.
(b) From a speed below VC/MC, with power to
maintain stabilized level flight at this speed, the airplane is upset
so as to accelerate through VC/MC at a flight
path 15 degrees below the initial path (or at the steepest nose-down
attitude that the system will permit with full control authority if
less than 15 degrees). The pilot's controls may be in the neutral
position after reaching VC/MC and before recovery
is initiated. Recovery may be initiated 3 seconds after operation of
the high-speed warning system by application of a load of 1.5g (0.5
acceleration increment), or such greater load factor that is
automatically applied by the system with the pilot's pitch control
neutral. Power may be reduced simultaneously. All other means of
decelerating the airplane, the use of which is authorized up to the
highest speed reached in the maneuver, may be used. The interval
between successive pilot actions must not be less than 1 second.
2. The applicant must also demonstrate that the speed margin,
established as above, will not be exceeded in inadvertent or gust-
induced upsets resulting in initiation of the dive from non-symmetric
attitudes, unless the airplane is protected by the flight-control laws
from getting into non-symmetric upset conditions. The upset maneuvers
described in Advisory Circular 25-7C, ``Flight Test Guide for
Certification of Transport Category Airplanes,'' section 8, paragraph
32, sub-paragraphs c(3)(a), (b), and (c), may be used to comply with
this requirement.
3. The probability of any failure of the high-speed protection
system, which would result in an airspeed exceeding those determined by
Special Conditions 1 and 2, must be less than 10-\5\ per
flight hour.
4. Failures of the system must be annunciated to the pilots. Flight
manual instructions must be provided that reduce the maximum operating
speeds, VMO/MMO. With the system failed, the
operating speed must be reduced to a value that maintains a speed
margin between VMO/MMO and VD/
MD, and that is consistent with showing compliance with
Sec. 25.335(b) without the benefit of the high-speed protection
system.
5. The applicant may request that the Master Minimum Equipment List
relief for the high-speed protection system be considered by the FAA
Flight Operations Evaluation Board, provided that the flight manual
instructions indicate reduced maximum operating speeds as described in
Special Condition 4. In addition, the flightdeck display of the reduced
operating speeds, as well as the overspeed warning for exceeding those
speeds, must be equivalent to that of the normal airplane with the
high-speed protection system operative. Also, the applicant must show
that no additional hazards are introduced with the high-speed
protection system inoperative.
Issued in Renton, Washington, September 25, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2015-25275 Filed 10-2-15; 8:45 am]
BILLING CODE 4910-13-P
