Special Conditions: Dassault Aviation Model Falcon 5X Airplane, Pilot-Compartment View Through Hydrophobic Windshield Coatings in Lieu of Windshield Wipers, 55226-55228 [2015-23099]
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Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2014–1075; Special
Conditions No. 25–599–SC]
Special Conditions: Dassault Aviation
Model Falcon 5X Airplane, PilotCompartment View Through
Hydrophobic Windshield Coatings in
Lieu of Windshield Wipers
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comment.
AGENCY:
These special conditions are
issued for the Dassault Model Falcon 5X
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
hydrophobic windshield coatings in
lieu of windshield wipers. The
applicable airworthiness regulations do
not contain adequate or appropriate
safety standards for this design feature.
These special conditions contain the
additional safety standards that the
Administrator considers necessary to
establish a level of safety equivalent to
that established by the existing
airworthiness standards.
DATES: This action is effective on
Dassault Aviation on September 15,
2015. We must receive your comments
by October 30, 2015.
ADDRESSES: Send comments identified
by docket number FAA–2014–1075
using any of the following methods:
• Federal eRegulations Portal: Go to
https://www.regulations.gov/ and follow
the online instructions for sending your
comments electronically.
• Mail: Send comments to Docket
Operations, M–30, U.S. Department of
Transportation (DOT), 1200 New Jersey
Avenue SE., Room W12–140, West
Building Ground Floor, Washington, DC
20590–0001.
• Hand Delivery or Courier: Take
comments to Docket Operations in
Room W12–140 of the West Building
Ground Floor at 1200 New Jersey
Avenue SE., Washington, DC, between 9
a.m. and 5 p.m., Monday through
Friday, except Federal holidays.
• Fax: Fax comments to Docket
Operations at 202–493–2251.
Privacy: The FAA will post all
comments it receives, without change,
to https://www.regulations.gov/,
including any personal information the
commenter provides. Using the search
mstockstill on DSK4VPTVN1PROD with RULES
SUMMARY:
VerDate Sep<11>2014
19:08 Sep 14, 2015
Jkt 235001
function of the docket Web site, anyone
can find and read the electronic form of
all comments received into any FAA
docket, including the name of the
individual sending the comment (or
signing the comment for an association,
business, labor union, etc.). DOT’s
complete Privacy Act Statement can be
found in the Federal Register published
on April 11, 2000 (65 FR 19477–19478),
as well as at https://DocketsInfo.dot
.gov/.
Docket: Background documents or
comments received may be read at
https://www.regulations.gov/ at any time.
Follow the online instructions for
accessing the docket or go to Docket
Operations in Room W12–140 of the
West Building Ground Floor at 1200
New Jersey Avenue SE., Washington,
DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Bob
Hettman, ANM–112, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98057–3356;
telephone (425) 227–2683; facsimile
(425) 227–1149.
SUPPLEMENTARY INFORMATION: The FAA
has determined that notice of, and
opportunity for prior public comment
on, these special conditions is
impracticable because these procedures
would significantly delay issuance of
the design approval and thus delivery of
the affected airplane(s).
In addition, the substance of these
special conditions has been subject to
the public comment process in several
prior instances with no substantive
comments received. The FAA therefore
finds that good cause exists for making
these special conditions effective upon
publication in the Federal Register.
Comments Invited
We invite interested people to take
part in this rulemaking by sending
written comments, data, or views. The
most helpful comments reference a
specific portion of the special
conditions, explain the reason for any
recommended change, and include
supporting data.
We will consider all comments we
receive by the closing date for
comments. We may change these special
conditions based on the comments we
receive.
Background
On July 1, 2012, Dassault Aviation
applied for a type certificate for their
new Model Falcon 5X airplane.
The Model Falcon 5X airplane is a
large, transport-category airplane to be
operated in private/corporate
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Sfmt 4700
transportation with a maximum of 19
passengers. The airplane incorporates a
low, swept-wing design with winglets;
twin rear-fuselage-mounted engines;
and the newest generation of Dassault
Aviation’s EASy flightdeck.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.17,
Dassault Aviation must show that the
Model Falcon 5X airplane meets the
applicable provisions of part 25, as
amended by Amendments 25–1 through
25–136.
The certification basis includes
certain special conditions, exemptions,
or later amended sections of the
applicable part 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 the Model Falcon 5X airplane
because of a novel or unusual design
feature, special conditions are
prescribed under the provisions of
§ 21.16.
Special conditions are initially
applicable to the model for which they
are issued. Should the type certificate
for that model be amended later to
include any other model that
incorporates the same novel or unusual
design feature, or should any other
model already included on the same
type certificate be modified to
incorporate the same novel or unusual
design feature, these special conditions
would also apply to the other model
under § 21.101.
In addition to the applicable
airworthiness regulations and special
conditions, the Model Falcon 5X
airplane must comply with the fuel-vent
and exhaust-emission requirements of
part 34, and the noise-certification
requirements of part 36.
The FAA issues special conditions, as
defined in 14 CFR 11.19, in accordance
with § 11.38, and they become part of
the type-certification basis under
§ 21.101.
Novel or Unusual Design Features
The Dassault Model Falcon 5X
airplane will incorporate the following
novel or unusual design feature:
The airplane flightdeck design
incorporates a hydrophobic windshield
coating that, during precipitation,
provides an adequate outside view from
the pilot compartment. Sole reliance on
such a coating, without windshield
wipers, constitutes a novel or unusual
design feature for which the applicable
airworthiness regulations do not contain
adequate or appropriate safety
E:\FR\FM\15SER1.SGM
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Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations
standards. Therefore, special conditions
are required to provide a level of safety
equivalent to that established by the
regulations.
mstockstill on DSK4VPTVN1PROD with RULES
Discussion
Section 25.773(b)(1) requires a means
to maintain a clear portion of the
windshield for both pilots operating a
transport-category airplane to have a
sufficiently extensive view along the
flight path during precipitation
conditions. The regulations require this
means to maintain such an area of clear
vision during heavy-rain precipitation at
airplane speeds up to 1.5 VSR1.
This requirement has existed in
principle since 1953 in part 4b of the
‘‘Civil Air Regulations’’ (CAR). Section
4b.351(b)(1) required that ‘‘Means shall
be provided for maintaining a sufficient
portion of the windshield clear so that
both pilots are afforded a sufficiently
extensive view along the flight path in
all normal flight attitudes of the
airplane. Such means shall be designed
to function under the following
conditions without continuous attention
on the part of the crew: (i) In heavy rain
at speeds up to 1.6 VS1, flaps retracted.’’
Effective December 26, 2002,
Amendment 25–108 changed the speed
for effectiveness of the means to
maintain an area of clear vision from up
to 1.6 VS1 to 1.5 VSR1 to accommodate
the redefinition of the reference stall
speed from the minimum speed in the
stall, VS1, to greater than or equal to the
1g stall speed, VSR1. As noted in the
preamble to the final rule for that
amendment, the reduced factor of 1.5 on
VSR1 is to maintain approximately the
same speed as the 1.6 factor on VS1.
The requirement that the means to
maintain a clear area of forward vision
must function at high speeds and high
precipitation rates is based on the use of
windshield wipers as the means to
maintain an adequate area of clear
vision in precipitation conditions. The
requirement in 14 CFR 121.313(b) and
125.213(b) to provide ‘‘. . . a
windshield wiper or equivalent for each
pilot station . . .’’ has remained
unchanged since at least 1953.
The effectiveness of windshield
wipers to maintain an area of clear
vision normally degrades as airspeed
and precipitation rates increase. It is
assumed that because high speeds and
high precipitation rates represent
limiting conditions for windshield
wipers, they will also be effective at
lower speeds and precipitation levels.
Accordingly, § 25.773(b)(1)(i) does not
require maintenance of a clear area of
forward vision at lower speeds or lower
precipitation rates.
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19:08 Sep 14, 2015
Jkt 235001
A forced airflow blown directly over
the windshield has also been used to
maintain an area of clear vision in
precipitation. The limiting conditions
for this technology are comparable to
those for windshield wipers.
Accordingly, introduction of this
technology did not present a need for
special conditions to maintain the level
of safety embodied in the existing
regulations.
Hydrophobic windshield coatings
may depend to some degree on airflow
to maintain a clear-vision area. The
heavy rain and high speed conditions
specified in the current rule do not
necessarily represent the limiting
condition for this new technology. For
example, airflow over the windshield,
which may be necessary to remove
moisture from the windshield, may not
be adequate to maintain a sufficiently
clear-vision area of the windshield in
low-speed flight or during surface
operations. Alternatively, airflow over
the windshield may be disturbed during
such critical times as the approach to
land, where the airplane is at a higherthan-normal pitch attitude. In these
cases, areas of airflow disturbance or
separation on the windshield could
cause failure to maintain a clear-vision
area on the windshield.
In addition to potentially depending
on airflow to function effectively,
hydrophobic coatings may also be
dependent on water-droplet size for
effective precipitation removal. For
example, precipitation in the form of a
light mist may not be sufficient for the
coating’s properties to result in
maintaining a clear area of vision.
The current regulations identify speed
and precipitation rate requirements that
represent limiting conditions for
windshield wipers and blowers, but not
for hydrophobic coatings. Likewise, it is
necessary to issue special conditions to
maintain the level of safety represented
by the current regulations.
These special conditions provide an
appropriate safety standard for the
hydrophobic-coating technology as the
means to maintain a clear area of vision
by requiring the coating to be effective
at low speeds and low precipitation
rates, as well as at the higher speeds and
precipitation rates identified in the
current regulation. These special
conditions are the only new or changed
requirements relative to those in
§ 25.773(b)(1) at Amendment 25–108.
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.
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55227
Applicability
As discussed above, these special
conditions are applicable to the Dassault
Falcon 5X airplane. Should Dassault
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 the
Dassault Falcon 5X airplane. It is not a
rule of general applicability.
The substance of these special
conditions has been subjected to the
notice and comment period in several
prior instances and has been derived
without substantive change from those
previously issued. It is unlikely that
prior public comment would result in a
significant change from the substance
contained herein. Therefore, because a
delay would significantly affect the
certification of the airplane, which is
imminent, the FAA has determined that
prior public notice and comment are
unnecessary and impracticable, and
good cause exists for adopting these
special conditions upon publication in
the Federal Register. The FAA is
requesting comments to allow interested
persons to submit views that may not
have been submitted in response to the
prior opportunities for comment
described above.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for these
special conditions is as follows:
Authority: 49106(g), 40113, 44701, 44702,
44704.
The Special Conditions
Accordingly, pursuant to the
authority delegated to me by the
Administrator, the following special
conditions are issued as part of the typecertification basis for Dassault Falcon
5X airplanes.
The airplane must have a means to
maintain a clear portion of the
windshield, during precipitation
conditions, enough for both pilots to
have a sufficiently extensive view along
the ground or flight path in normal taxi
and flight attitudes of the airplane. This
means must be designed to function,
without continuous attention on the
part of the flightcrew, in conditions
from light misting precipitation to heavy
rain, at speeds from fully stopped in
still air, to 1.5 VSR1 with lift and drag
devices retracted.
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55228
Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations
Issued in Renton, Washington, on
September 9, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 2015–23099 Filed 9–14–15; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2015–1483; Special
Conditions No. 25–598–SC]
Special Conditions: Gulfstream
Aerospace Corporation Model GVII–
G500 Airplanes; Limit Engine Torque
Loads
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Gulfstream Model GVII–
G500 airplane. These airplanes have a
novel or unusual design feature as
compared to the state of technology
envisioned in the airworthiness
standards for transport category
airplanes. This design feature includes
engine size and the potential torque
loads imposed by sudden engine
stoppage. 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: The effective date of these
special conditions is September 15,
2015. We must receive your comments
by October 30, 2015.
ADDRESSES: Send comments identified
by docket number FAA–2015–1483
using any of the following methods:
• Federal eRegulations Portal: Go to
https://www.regulations.gov/ and follow
the online instructions for sending your
comments electronically.
• Mail: Send comments to Docket
Operations, M–30, U.S. Department of
Transportation (DOT), 1200 New Jersey
Avenue SE., Room W12–140, West
Building Ground Floor, Washington, DC
20590–0001.
• Hand Delivery or Courier: Take
comments to Docket Operations in
Room W12–140 of the West Building
Ground Floor at 1200 New Jersey
Avenue SE., Washington, DC, between 9
mstockstill on DSK4VPTVN1PROD with RULES
SUMMARY:
VerDate Sep<11>2014
19:08 Sep 14, 2015
Jkt 235001
a.m. and 5 p.m., Monday through
Friday, except Federal holidays.
• Fax: Fax comments to Docket
Operations at 202–493–2251.
Privacy: The FAA will post all
comments it receives, without change,
to https://www.regulations.gov/,
including any personal information the
commenter provides. Using the search
function of the docket Web site, anyone
can find and read the electronic form of
all comments received into any FAA
docket, including the name of the
individual sending the comment (or
signing the comment for an association,
business, labor union, etc.). DOT’s
complete Privacy Act Statement can be
found in the Federal Register published
on April 11, 2000 (65 FR 19477–19478),
as well as at https://DocketsInfo.dot
.gov/.
Docket: Background documents or
comments received may be read at
https://www.regulations.gov/ at any time.
Follow the online instructions for
accessing the docket or go to Docket
Operations in Room W12–140 of the
West Building Ground Floor at 1200
New Jersey Avenue SE., Washington,
DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: 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: The FAA
has determined that notice of, and
opportunity for, prior public comment
on these special conditions are
impracticable because these procedures
would significantly delay issuance of
the design approval and thus delivery of
the affected airplane.
In addition, the substance of these
special conditions has been subject to
the public-comment process in several
prior instances with no substantive
comments received. The FAA therefore
finds that good cause exists for making
these special conditions effective upon
issuance.
Comments Invited
We invite interested people to take
part in this rulemaking by sending
written comments, data, or views. The
most helpful comments reference a
specific portion of the special
conditions, explain the reason for any
recommended change, and include
supporting data.
We will consider all comments we
receive on or before the closing date for
comments. We may change these special
PO 00000
Frm 00008
Fmt 4700
Sfmt 4700
conditions based on the comments we
receive.
Background
On March 29, 2012, Gulfstream
Aerospace Corporation applied for a
type certificate for their new Model
GVII–G500 airplane.
The GVII airplane is a large-cabin
business jet with seating for 19
passengers. It incorporates a low, sweptwing design with winglets and a T-tail.
The Model GVII–G500 airplane is
powered by two aft-fuselage-mounted
Pratt & Whitney turbofan engines.
Avionics will include four primary
display units and multiple touchscreen
controllers. The flight-control system is
a three-axis fly-by-wire system
controlled by active control/coupled
side sticks.
The Model GVII–G500 airplane
wingspan is approximately 87 ft with a
length of just over 91 ft. Maximum
takeoff weight will be approximately
76,850 lbs and maximum takeoff thrust
will be approximately 15,135 lbs.
Maximum range will be approximately
5,000 nm and maximum operating
altitude will be 51,000 ft.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.17,
Gulfstream Aerospace Corporation must
show that the Model GVII–500 airplane
meets the applicable provisions of part
25, as amended by Amendments 25–1
through 25–137 thereto.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 25) do not contain
adequate or appropriate safety standards
for the Model GVII–G500 airplane
because of a novel or unusual design
feature, special conditions are
prescribed under the provisions of
§ 21.16.
Special conditions are initially
applicable to the model for which they
are issued. Should the type certificate
for that model be amended later to
include any other model that
incorporates the same or similar novel
or unusual design feature, the special
conditions would also apply to the other
model under § 21.101.
In addition to the applicable
airworthiness regulations and special
conditions, the 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.
The FAA issues special conditions, as
defined in 14 CFR 11.19, in accordance
with § 11.38, and they become part of
E:\FR\FM\15SER1.SGM
15SER1
]]>Agencies
[Federal Register Volume 80, Number 178 (Tuesday, September 15, 2015)]
[Rules and Regulations]
[Pages 55226-55228]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-23099]
[[Page 55226]]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2014-1075; Special Conditions No. 25-599-SC]
Special Conditions: Dassault Aviation Model Falcon 5X Airplane,
Pilot-Compartment View Through Hydrophobic Windshield Coatings in Lieu
of Windshield Wipers
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comment.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Dassault Model
Falcon 5X 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 hydrophobic windshield coatings in lieu of windshield
wipers. The applicable airworthiness regulations do not contain
adequate or appropriate safety standards for this design feature. These
special conditions contain the additional safety standards that the
Administrator considers necessary to establish a level of safety
equivalent to that established by the existing airworthiness standards.
DATES: This action is effective on Dassault Aviation on September 15,
2015. We must receive your comments by October 30, 2015.
ADDRESSES: Send comments identified by docket number FAA-2014-1075
using any of the following methods:
Federal eRegulations Portal: Go to https://www.regulations.gov/ and follow the online instructions for sending
your comments electronically.
Mail: Send comments to Docket Operations, M-30, U.S.
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
Hand Delivery or Courier: Take comments to Docket
Operations in Room W12-140 of the West Building Ground Floor at 1200
New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: The FAA will post all comments it receives, without
change, to https://www.regulations.gov/, including any personal
information the commenter provides. Using the search function of the
docket Web site, anyone can find and read the electronic form of all
comments received into any FAA docket, including the name of the
individual sending the comment (or signing the comment for an
association, business, labor union, etc.). DOT's complete Privacy Act
Statement can be found in the Federal Register published on April 11,
2000 (65 FR 19477-19478), as well as at https://DocketsInfo.dot.gov/.
Docket: Background documents or comments received may be read at
https://www.regulations.gov/ at any time. Follow the online instructions
for accessing the docket or go to Docket Operations in Room W12-140 of
the West Building Ground Floor at 1200 New Jersey Avenue SE.,
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Bob Hettman, ANM-112, Transport
Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue
SW., Renton, Washington 98057-3356; telephone (425) 227-2683; facsimile
(425) 227-1149.
SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and
opportunity for prior public comment on, these special conditions is
impracticable because these procedures would significantly delay
issuance of the design approval and thus delivery of the affected
airplane(s).
In addition, the substance of these special conditions has been
subject to the public comment process in several prior instances with
no substantive comments received. The FAA therefore finds that good
cause exists for making these special conditions effective upon
publication in the Federal Register.
Comments Invited
We invite interested people to take part in this rulemaking by
sending written comments, data, or views. The most helpful comments
reference a specific portion of the special conditions, explain the
reason for any recommended change, and include supporting data.
We will consider all comments we receive by the closing date for
comments. We may change these special conditions based on the comments
we receive.
Background
On July 1, 2012, Dassault Aviation applied for a type certificate
for their new Model Falcon 5X airplane.
The Model Falcon 5X airplane is a large, transport-category
airplane to be operated in private/corporate transportation with a
maximum of 19 passengers. The airplane incorporates a low, swept-wing
design with winglets; twin rear-fuselage-mounted engines; and the
newest generation of Dassault Aviation's EASy flightdeck.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.17, Dassault Aviation must show that the Model Falcon 5X
airplane meets the applicable provisions of part 25, as amended by
Amendments 25-1 through 25-136.
The certification basis includes certain special conditions,
exemptions, or later amended sections of the applicable part 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 the Model Falcon 5X airplane because
of a novel or unusual design feature, special conditions are prescribed
under the provisions of Sec. 21.16.
Special conditions are initially applicable to the model for which
they are issued. Should the type certificate for that model be amended
later to include any other model that incorporates the same novel or
unusual design feature, or should any other model already included on
the same type certificate be modified to incorporate the same novel or
unusual design feature, these special conditions would also apply to
the other model under Sec. 21.101.
In addition to the applicable airworthiness regulations and special
conditions, the Model Falcon 5X airplane must comply with the fuel-vent
and exhaust-emission requirements of part 34, and the noise-
certification requirements of part 36.
The FAA issues special conditions, as defined in 14 CFR 11.19, in
accordance with Sec. 11.38, and they become part of the type-
certification basis under Sec. 21.101.
Novel or Unusual Design Features
The Dassault Model Falcon 5X airplane will incorporate the
following novel or unusual design feature:
The airplane flightdeck design incorporates a hydrophobic
windshield coating that, during precipitation, provides an adequate
outside view from the pilot compartment. Sole reliance on such a
coating, without windshield wipers, constitutes a novel or unusual
design feature for which the applicable airworthiness regulations do
not contain adequate or appropriate safety
[[Page 55227]]
standards. Therefore, special conditions are required to provide a
level of safety equivalent to that established by the regulations.
Discussion
Section 25.773(b)(1) requires a means to maintain a clear portion
of the windshield for both pilots operating a transport-category
airplane to have a sufficiently extensive view along the flight path
during precipitation conditions. The regulations require this means to
maintain such an area of clear vision during heavy-rain precipitation
at airplane speeds up to 1.5 VSR1.
This requirement has existed in principle since 1953 in part 4b of
the ``Civil Air Regulations'' (CAR). Section 4b.351(b)(1) required that
``Means shall be provided for maintaining a sufficient portion of the
windshield clear so that both pilots are afforded a sufficiently
extensive view along the flight path in all normal flight attitudes of
the airplane. Such means shall be designed to function under the
following conditions without continuous attention on the part of the
crew: (i) In heavy rain at speeds up to 1.6 VS1, flaps
retracted.''
Effective December 26, 2002, Amendment 25-108 changed the speed for
effectiveness of the means to maintain an area of clear vision from up
to 1.6 VS1 to 1.5 VSR1 to accommodate the
redefinition of the reference stall speed from the minimum speed in the
stall, VS1, to greater than or equal to the 1g stall speed,
VSR1. As noted in the preamble to the final rule for that
amendment, the reduced factor of 1.5 on VSR1 is to maintain
approximately the same speed as the 1.6 factor on VS1.
The requirement that the means to maintain a clear area of forward
vision must function at high speeds and high precipitation rates is
based on the use of windshield wipers as the means to maintain an
adequate area of clear vision in precipitation conditions. The
requirement in 14 CFR 121.313(b) and 125.213(b) to provide ``. . . a
windshield wiper or equivalent for each pilot station . . .'' has
remained unchanged since at least 1953.
The effectiveness of windshield wipers to maintain an area of clear
vision normally degrades as airspeed and precipitation rates increase.
It is assumed that because high speeds and high precipitation rates
represent limiting conditions for windshield wipers, they will also be
effective at lower speeds and precipitation levels. Accordingly, Sec.
25.773(b)(1)(i) does not require maintenance of a clear area of forward
vision at lower speeds or lower precipitation rates.
A forced airflow blown directly over the windshield has also been
used to maintain an area of clear vision in precipitation. The limiting
conditions for this technology are comparable to those for windshield
wipers. Accordingly, introduction of this technology did not present a
need for special conditions to maintain the level of safety embodied in
the existing regulations.
Hydrophobic windshield coatings may depend to some degree on
airflow to maintain a clear-vision area. The heavy rain and high speed
conditions specified in the current rule do not necessarily represent
the limiting condition for this new technology. For example, airflow
over the windshield, which may be necessary to remove moisture from the
windshield, may not be adequate to maintain a sufficiently clear-vision
area of the windshield in low-speed flight or during surface
operations. Alternatively, airflow over the windshield may be disturbed
during such critical times as the approach to land, where the airplane
is at a higher-than-normal pitch attitude. In these cases, areas of
airflow disturbance or separation on the windshield could cause failure
to maintain a clear-vision area on the windshield.
In addition to potentially depending on airflow to function
effectively, hydrophobic coatings may also be dependent on water-
droplet size for effective precipitation removal. For example,
precipitation in the form of a light mist may not be sufficient for the
coating's properties to result in maintaining a clear area of vision.
The current regulations identify speed and precipitation rate
requirements that represent limiting conditions for windshield wipers
and blowers, but not for hydrophobic coatings. Likewise, it is
necessary to issue special conditions to maintain the level of safety
represented by the current regulations.
These special conditions provide an appropriate safety standard for
the hydrophobic-coating technology as the means to maintain a clear
area of vision by requiring the coating to be effective at low speeds
and low precipitation rates, as well as at the higher speeds and
precipitation rates identified in the current regulation. These special
conditions are the only new or changed requirements relative to those
in Sec. 25.773(b)(1) at Amendment 25-108.
These special conditions contain the additional safety standards
that the Administrator considers necessary to establish a level of
safety equivalent to that established by the existing airworthiness
standards.
Applicability
As discussed above, these special conditions are applicable to the
Dassault Falcon 5X airplane. Should Dassault 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 the Dassault Falcon 5X airplane. It is not a rule of general
applicability.
The substance of these special conditions has been subjected to the
notice and comment period in several prior instances and has been
derived without substantive change from those previously issued. It is
unlikely that prior public comment would result in a significant change
from the substance contained herein. Therefore, because a delay would
significantly affect the certification of the airplane, which is
imminent, the FAA has determined that prior public notice and comment
are unnecessary and impracticable, and good cause exists for adopting
these special conditions upon publication in the Federal Register. The
FAA is requesting comments to allow interested persons to submit views
that may not have been submitted in response to the prior opportunities
for comment described above.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
The authority citation for these special conditions is as follows:
Authority: 49106(g), 40113, 44701, 44702, 44704.
The Special Conditions
Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type-certification basis for Dassault Falcon 5X airplanes.
The airplane must have a means to maintain a clear portion of the
windshield, during precipitation conditions, enough for both pilots to
have a sufficiently extensive view along the ground or flight path in
normal taxi and flight attitudes of the airplane. This means must be
designed to function, without continuous attention on the part of the
flightcrew, in conditions from light misting precipitation to heavy
rain, at speeds from fully stopped in still air, to 1.5 VSR1
with lift and drag devices retracted.
[[Page 55228]]
Issued in Renton, Washington, on September 9, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2015-23099 Filed 9-14-15; 8:45 am]
BILLING CODE 4910-13-P
