Special Conditions: Gulfstream Aerospace Corporation Model G-1159A Airplanes; High-Intensity Radiated Fields (HIRF), 1137-1139 [E7-197]
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Federal Register / Vol. 72, No. 6 / Wednesday, January 10, 2007 / Rules and Regulations
coating’s properties to result in
maintaining a clear area of vision.
In summary, the current regulations
identify speed and precipitation rate
requirements that represent limiting
conditions for windshield wipers and
blowers, but not for hydrophobic
coatings, so 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 it to be effective at low
speeds and precipitation rates as well as
the higher speeds and precipitation
rates identified in the current
regulation. These are the only new or
changed requirements relative to those
in § 25.773(b)(1) at Amendment 25–108.
Discussion of Comments
Notice of proposed special condition
No. 25–06–07 for the Dassault Aviation
Model Falcon 7X airplane was
published in the Federal Register on
July 12, 2006 (71 FR 39235). No
comments were received and this
special condition is adopted as
proposed.
The Special Condition
Accordingly, pursuant to the
authority delegated to me by the
Administrator, the following special
condition is issued as part of the type
certification basis for Dassault Aviation
Model Falcon 7X airplanes.
Pilot Compartment View—Hydrophobic
Coatings in Lieu of Windshield Wipers
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 crew, 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.
Issued in Renton, Washington, on
December 29, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. E7–200 Filed 1–9–07; 8:45 am]
BILLING CODE 4910–13–P
Applicability
As discussed above, this special
condition is applicable to the Model
Falcon 7X. Should Dassault Aviation
apply at a later date for a change to the
type certificate to include another
model on the same type certificate
incorporating the same novel or unusual
design feature, the special condition
would apply to that model as well.
Effective Upon Issuance
Under standard practice, the effective
date of final special conditions would
be 30 days after the date of publication
in the Federal Register; however, as the
certification date for the Dassault Model
Falcon 7X is imminent, the FAA finds
that good cause exists to make this
special condition effective upon
issuance.
Conclusion
This action affects only certain novel
or unusual design features on one model
of airplane. It is not a rule of general
applicability.
mstockstill on PROD1PC61 with RULES
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for this special
condition is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
VerDate Aug<31>2005
14:45 Jan 09, 2007
Jkt 211001
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM363; Special Conditions No.
25–344–SC]
Special Conditions: Gulfstream
Aerospace Corporation Model G–
1159A Airplanes; High-Intensity
Radiated Fields (HIRF)
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
SUMMARY: The FAA issues these special
conditions for a Gulfstream Aerospace
Corporation Model G–1159A airplane
modified by AeroMech Incorporated.
This modified 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. The modification
incorporates the installation of
Innovative Solutions and Support
integrated air data display units
(ADDU). These systems perform critical
functions. The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for the
PO 00000
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Fmt 4700
Sfmt 4700
1137
protection of these systems from the
effects of high-intensity radiated fields
(HIRF). 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 December 29,
2006. We must receive your comments
on or before February 9, 2007.
ADDRESSES: You may mail or deliver
comments on these special conditions
in duplicate to: Federal Aviation
Administration, Transport Airplane
Directorate, Attention: Rules Docket
(ANM–113), Docket No. NM363, 1601
Lind Avenue, SW., Renton, Washington
98057–3356. You must mark your
comments Docket No. NM363.
FOR FURTHER INFORMATION CONTACT: Greg
Dunn, FAA, Airplane and Flight Crew
Interface Branch, ANM–111, Transport
Airplane Directorate, Aircraft
Certification Service, 1601 Lind
Avenue, SW., Renton, Washington
98057–3356; telephone (425) 227–2799;
facsimile (425) 227–1320.
SUPPLEMENTARY INFORMATION:
Comments Invited
The FAA has determined that notice
and opportunity for prior public
comment for these special conditions is
impracticable because these procedures
would significantly delay certification
and delivery of the affected aircraft. 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. We therefore find that good
cause exists for making these special
conditions effective upon issuance.
However, we invite interested persons
to take part in this rulemaking by
submitting written comments. 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
about 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
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1138
Federal Register / Vol. 72, No. 6 / Wednesday, January 10, 2007 / Rules and Regulations
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
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.
mstockstill on PROD1PC61 with RULES
Background
On September 29, 2006, AeroMech
Incorporated, 1616 Hewitt Avenue,
Suite 312, Everett, Washington 98201,
applied for a supplemental type
certificate (STC) to modify a Gulfstream
Aerospace Corporation model G–1159A
airplane. The Gulfstream Aerospace
Corporation Model G–1159A airplane is
a small transport category airplane
powered by two turbine engines. It
operates with a 2-pilot crew and can
seat up to 15 passengers. The
modification incorporates the
installation of Innovative Solutions and
Support integrated air data display
units. These systems have a potential to
be vulnerable to high-intensity radiated
fields (HIRF) external to the airplane.
Type Certification Basis
Under the provisions of 14 CFR
21.101, AeroMech Incorporated must
show that Gulfstream Aerospace
Corporation Model G–1159A airplane,
as changed, continues to meet the
applicable provisions of the regulations
incorporated by reference in Type
Certificate No. A12EA, 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 specific
regulations are 14 CFR part 25 as
amended by Amendments 25–1 through
25–8, 25–10, 25–12, 25–16 through 25–
22, 25–24, 25–26, 25–27, 25–29 through
25–34, 25–37, 25–40 (as applicable to a
new APU installation); § 25.1309 as
amended by Amendment 25–41, and
§ 25.1329 (as applied to a new autopilot
installation), § 25.994 (crashworthiness
fuel system components), and § 25.581
(lightning protection), as amended by
Amendment 25–23; and Special part 27,
as amended by Amendment 27–2 (fuel
venting emission). The special
conditions contained in the FAA’s letter
to Grumman dated September 27, 1965,
applicable to the Gulfstream Model G–
1159 airplane, are also applicable to the
Gulfstream Model G–1159A airplane,
except that reference to Civil Air
Regulations 4b.450 in the ‘‘Cooling
VerDate Aug<31>2005
14:45 Jan 09, 2007
Jkt 211001
Systems’’ special conditions is replaced
by § 25.1043, effective February 1, 1965.
In addition, the special conditions
pertaining to dynamic gust loads
contained in the FAA AEA–212 letter
dated July 22, 1980.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., part 25, as amended) do not
contain adequate or appropriate safety
standards for the Gulfstream Aerospace
Corporation Model G–1159A airplane
because of a novel or unusual design
feature, special conditions are
prescribed under § 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, Gulfstream Aerospace
Corporation Model G–1159A airplane
must comply with the fuel vent and
exhaust emission requirements of 14
CFR part 34 and the noise certification
requirements of 14 CFR part 36.
The FAA issues special conditions, as
defined in § 11.19, under § 11.38, and
they become part of the type
certification basis under the provisions
of § 21.101.
Novel or Unusual Design Features
As noted earlier, Gulfstream
Aerospace Corporation G–1159A
airplane modified by AeroMech
Incorporated will incorporate
Innovative Solutions and Support
integrated air data display units that
will perform critical functions. These
systems may be vulnerable to highintensity radiated fields external to the
airplane. Current airworthiness
standards of part 25 do not contain
adequate or appropriate safety standards
for protecting this equipment from
adverse effects of HIRF. So this system
is considered to be a novel or unusual
design feature.
Discussion
There is no specific regulation that
addresses protection requirements for
electrical and electronic systems from
HIRF. Increased power levels from
ground-based radio transmitters and the
growing use of sensitive avionics/
electronics and electrical systems to
command and control airplanes have
made it necessary to provide adequate
protection.
To ensure that a level of safety is
achieved equivalent to that intended by
the regulations incorporated by
reference, special conditions are needed
for the Gulfstream Aerospace
Corporation G–1159A airplane modified
by AeroMech Incorporated. These
special conditions require that new
avionics/electronics and electrical
systems that perform critical functions
be designed and installed to preclude
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component damage and interruption of
function because of HIRF.
High-Intensity Radiated Fields (HIRF)
High-power radio frequency
transmitters for radio, radar, television,
and satellite communications can
adversely affect operation of airplane
electric and electronic systems.
Therefore, the immunity of critical
avionics/electronics and electrical
systems to HIRF must be established.
Based on surveys and analysis of
existing HIRF emitters, an adequate
level of protection exists when airplane
system immunity is demonstrated when
exposed to the HIRF environments in
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. System elements and their
associated wiring harnesses must be
exposed to the environment without
benefit of airframe shielding.
b. Demonstration of this level of
protection is established through system
tests and analysis.
2. An environment external to the
airframe of the field strengths shown in
the table below for the frequency ranges
indicated. Immunity to both peak and
average field strength components from
the table must 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 .........
Average
50
50
50
100
50
50
100
100
700
700
2000
3000
3000
1000
3000
2000
600
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 environmental levels identified
above are the result of an FAA review
of existing studies on the subject of
HIRF and of the work of the
Electromagnetic Effects Harmonization
Working Group of the Aviation
Rulemaking Advisory Committee.
Applicability
These special conditions are
applicable to a Gulfstream Aerospace
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Federal Register / Vol. 72, No. 6 / Wednesday, January 10, 2007 / Rules and Regulations
Corporation Model G–1159A airplane
modified by AeroMech Incorporated.
Should AeroMech Incorporated apply at
a later date for a supplemental type
certificate to modify any other similar
model included on Type Certificate No.
A12EA to incorporate the same or
similar novel or unusual design feature,
these special conditions would apply to
that model as well under § 21.101.
Conclusion
This action affects only certain novel
or unusual design features on a
Gulfstream Aerospace Corporation
Model G–1159A airplane modified by
AeroMech Incorporated. It is not a rule
of general applicability and affects only
the applicant who 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 Special Conditions
mstockstill on PROD1PC61 with RULES
Therefore, under the authority
delegated to me by the Administrator,
the following special conditions are
issued as part of the supplemental type
certification basis for the Gulfstream
Aerospace Corporation Model G–1159A
airplane modified by AeroMech
Incorporated.
1. Protection from Unwanted Effects
of High-Intensity Radiated Fields
(HIRF). Each electrical and electronic
system that performs critical functions
must be designed and installed to
ensure that the operation and
operational capability of these systems
to perform critical functions are not
adversely affected when the airplane is
exposed to high-intensity radiated
fields.
2. For the purpose of these special
conditions, 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
December 29, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. E7–197 Filed 1–9–07; 8:45 am]
BILLING CODE 4910–13–P
VerDate Aug<31>2005
14:45 Jan 09, 2007
Jkt 211001
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2006–25824; Directorate
Identifier 2004–SW–23–AD; Amendment 39–
14876; AD 2007–01–05]
RIN 2120–AA64
Airworthiness Directives; Sikorsky
Aircraft Corporation Model S–61L, N,
R, and NM Helicopters
Federal Aviation
Administration, DOT.
ACTION: Final rule.
AGENCY:
SUMMARY: This amendment adopts a
new airworthiness directive (AD) for the
specified Sikorsky Aircraft Corporation
(Sikorsky) model helicopters that
requires, within a specified time,
creating a component history card or
equivalent record. The AD also requires
recording the hours time-in-service
(TIS) and the external lift cycles (lift
cycles) for each main gearbox input left
and right freewheel unit (IFWU)
assembly. Also, the AD requires
calculating a moving average of lift
cycles per hour TIS at specified
intervals on each IFWU assembly. The
moving average is used to determine if
an IFWU assembly is used in repetitive
external lift (REL) or non-REL helicopter
operations. If an IFWU assembly is used
in REL operations, this AD requires a
visual and dimensional inspection of
the IFWU assembly at specified
intervals. This AD also requires
recording certain information and
replacing each part that is beyond the
wear limits or that exhibits visual
surface distress with an airworthy part.
In addition, this AD requires
permanently marking the REL IFWU
camshafts and gear housings with the
letters ‘‘REL’’ on the surface of these
parts. This amendment is prompted by
an accident in which the left and right
IFWU assembly on a helicopter slipped
or disengaged resulting in both engines
over speeding, engine shutdowns, and
loss of engine power to the
transmissions. The actions specified by
this AD are intended to prevent slipping
in the IFWU assembly, loss of engine
power to the transmissions, and
subsequent loss of control of the
helicopter.
Effective February 14, 2007.
The incorporation by reference of
certain publications listed in the
regulations is approved by the Director
of the Federal Register as of February
14, 2007.
DATES:
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1139
You may get the service
information identified in this AD from
Sikorsky Aircraft Corporation, Attn:
Manager, Commercial Tech Support,
6900 Main Street, Stratford, Connecticut
06614, phone (203) 386–3001, fax (203)
386–5983.
ADDRESSES:
Examining the Docket
You may examine the docket that
contains this AD, any comments, and
other information on the Internet at
https://dms.dot.gov, or at the Docket
Management System (DMS), U.S.
Department of Transportation, 400
Seventh Street, SW., Room PL–401, on
the plaza level of the Nassif Building,
Washington, DC.
FOR FURTHER INFORMATION CONTACT: Kirk
Gustafson, Aviation Safety Engineer,
Boston Aircraft Certification Office,
Engine and Propeller Directorate, FAA,
12 New England Executive Park,
Burlington, MA 01803, telephone (781)
238–7190, fax (781) 238–7170.
SUPPLEMENTARY INFORMATION: A
proposal to amend 14 CFR part 39 to
include an AD for the specified model
helicopters was published in the
Federal Register on September 15, 2006
(71 FR 54443). That action proposed to
require, within a specified time, creating
a component history card or equivalent
record and counting and recording the
hours TIS and the lift cycles for each
IFWU assembly. A lift cycle is defined
as an external load lift and subsequent
release of that load. Also, the AD
proposed calculating a moving average
of lift cycles per hour TIS at specified
intervals on the IFWU assembly. The
moving average would determine if an
IFWU assembly is designated as an REL
or non-REL IFWU assembly. Once an
IFWU assembly is designated as an REL
IFWU assembly, the moving average
would no longer need to be calculated
for that IFWU assembly. For an IFWU
assembly designated as an REL IFWU
assembly, the AD proposed a repetitive
visual and dimensional inspection of
the IFWU assembly at 500 hours TIS or
7500 lift cycles whichever occurs first.
The AD proposed recording inspection
information, providing a copy of the
information to the FAA, and replacing
each part that is beyond the wear or
surface distress limits with an airworthy
part. In addition, the AD proposed
permanently marking the IFWU
camshaft and gear housing with the
letters ‘‘REL’’ on the surface of these
parts.
Sikorsky has issued Alert Service
Bulletin No. 61B35–67B, Revision B,
dated August 11, 2003 (ASB). The ASB
specifies implementing a moving
average procedure for determining REL
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]]>Agencies
[Federal Register Volume 72, Number 6 (Wednesday, January 10, 2007)]
[Rules and Regulations]
[Pages 1137-1139]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-197]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM363; Special Conditions No. 25-344-SC]
Special Conditions: Gulfstream Aerospace Corporation Model G-
1159A Airplanes; High-Intensity Radiated Fields (HIRF)
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: The FAA issues these special conditions for a Gulfstream
Aerospace Corporation Model G-1159A airplane modified by AeroMech
Incorporated. This modified 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. The
modification incorporates the installation of Innovative Solutions and
Support integrated air data display units (ADDU). These systems perform
critical functions. The applicable airworthiness regulations do not
contain adequate or appropriate safety standards for the protection of
these systems from the effects of high-intensity radiated fields
(HIRF). 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 December 29,
2006. We must receive your comments on or before February 9, 2007.
ADDRESSES: You may mail or deliver comments on these special conditions
in duplicate to: Federal Aviation Administration, Transport Airplane
Directorate, Attention: Rules Docket (ANM-113), Docket No. NM363, 1601
Lind Avenue, SW., Renton, Washington 98057-3356. You must mark your
comments Docket No. NM363.
FOR FURTHER INFORMATION CONTACT: Greg Dunn, FAA, Airplane and Flight
Crew Interface Branch, ANM-111, Transport Airplane Directorate,
Aircraft Certification Service, 1601 Lind Avenue, SW., Renton,
Washington 98057-3356; telephone (425) 227-2799; facsimile (425) 227-
1320.
SUPPLEMENTARY INFORMATION:
Comments Invited
The FAA has determined that notice and opportunity for prior public
comment for these special conditions is impracticable because these
procedures would significantly delay certification and delivery of the
affected aircraft. 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. We therefore
find that good cause exists for making these special conditions
effective upon issuance. However, we invite interested persons to take
part in this rulemaking by submitting written comments. 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
about 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
[[Page 1138]]
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 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 September 29, 2006, AeroMech Incorporated, 1616 Hewitt Avenue,
Suite 312, Everett, Washington 98201, applied for a supplemental type
certificate (STC) to modify a Gulfstream Aerospace Corporation model G-
1159A airplane. The Gulfstream Aerospace Corporation Model G-1159A
airplane is a small transport category airplane powered by two turbine
engines. It operates with a 2-pilot crew and can seat up to 15
passengers. The modification incorporates the installation of
Innovative Solutions and Support integrated air data display units.
These systems have a potential to be vulnerable to high-intensity
radiated fields (HIRF) external to the airplane.
Type Certification Basis
Under the provisions of 14 CFR 21.101, AeroMech Incorporated must
show that Gulfstream Aerospace Corporation Model G-1159A airplane, as
changed, continues to meet the applicable provisions of the regulations
incorporated by reference in Type Certificate No. A12EA, 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 specific regulations are 14 CFR part 25 as
amended by Amendments 25-1 through 25-8, 25-10, 25-12, 25-16 through
25-22, 25-24, 25-26, 25-27, 25-29 through 25-34, 25-37, 25-40 (as
applicable to a new APU installation); Sec. 25.1309 as amended by
Amendment 25-41, and Sec. 25.1329 (as applied to a new autopilot
installation), Sec. 25.994 (crashworthiness fuel system components),
and Sec. 25.581 (lightning protection), as amended by Amendment 25-23;
and Special part 27, as amended by Amendment 27-2 (fuel venting
emission). The special conditions contained in the FAA's letter to
Grumman dated September 27, 1965, applicable to the Gulfstream Model G-
1159 airplane, are also applicable to the Gulfstream Model G-1159A
airplane, except that reference to Civil Air Regulations 4b.450 in the
``Cooling Systems'' special conditions is replaced by Sec. 25.1043,
effective February 1, 1965. In addition, the special conditions
pertaining to dynamic gust loads contained in the FAA AEA-212 letter
dated July 22, 1980.
If the Administrator finds that the applicable airworthiness
regulations (i.e., part 25, as amended) do not contain adequate or
appropriate safety standards for the Gulfstream Aerospace Corporation
Model G-1159A airplane because of a novel or unusual design feature,
special conditions are prescribed under Sec. 21.16.
In addition to the applicable airworthiness regulations and special
conditions, Gulfstream Aerospace Corporation Model G-1159A airplane
must comply with the fuel vent and exhaust emission requirements of 14
CFR part 34 and the noise certification requirements of 14 CFR part 36.
The FAA issues special conditions, as defined in Sec. 11.19, under
Sec. 11.38, and they become part of the type certification basis under
the provisions of Sec. 21.101.
Novel or Unusual Design Features
As noted earlier, Gulfstream Aerospace Corporation G-1159A airplane
modified by AeroMech Incorporated will incorporate Innovative Solutions
and Support integrated air data display units that will perform
critical functions. These systems may be vulnerable to high-intensity
radiated fields external to the airplane. Current airworthiness
standards of part 25 do not contain adequate or appropriate safety
standards for protecting this equipment from adverse effects of HIRF.
So this system is considered to be a novel or unusual design feature.
Discussion
There is no specific regulation that addresses protection
requirements for electrical and electronic systems from HIRF. Increased
power levels from ground-based radio transmitters and the growing use
of sensitive avionics/electronics and electrical systems to command and
control airplanes have made it necessary to provide adequate
protection.
To ensure that a level of safety is achieved equivalent to that
intended by the regulations incorporated by reference, special
conditions are needed for the Gulfstream Aerospace Corporation G-1159A
airplane modified by AeroMech Incorporated. These special conditions
require that new avionics/electronics and electrical systems that
perform critical functions be designed and installed to preclude
component damage and interruption of function because of HIRF.
High-Intensity Radiated Fields (HIRF)
High-power radio frequency transmitters for radio, radar,
television, and satellite communications can adversely affect operation
of airplane electric and electronic systems. Therefore, the immunity of
critical avionics/electronics and electrical systems to HIRF must be
established.
Based on surveys and analysis of existing HIRF emitters, an
adequate level of protection exists when airplane system immunity is
demonstrated when exposed to the HIRF environments in 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. System elements and their associated wiring harnesses must be
exposed to the environment without benefit of airframe shielding.
b. Demonstration of this level of protection is established through
system tests and analysis.
2. An environment external to the airframe of the field strengths
shown in the table below for the frequency ranges indicated. Immunity
to both peak and average field strength components from the table must
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 environmental levels identified above are the result of an FAA
review of existing studies on the subject of HIRF and of the work of
the Electromagnetic Effects Harmonization Working Group of the Aviation
Rulemaking Advisory Committee.
Applicability
These special conditions are applicable to a Gulfstream Aerospace
[[Page 1139]]
Corporation Model G-1159A airplane modified by AeroMech Incorporated.
Should AeroMech Incorporated apply at a later date for a supplemental
type certificate to modify any other similar model included on Type
Certificate No. A12EA to incorporate the same or similar novel or
unusual design feature, these special conditions would apply to that
model as well under Sec. 21.101.
Conclusion
This action affects only certain novel or unusual design features
on a Gulfstream Aerospace Corporation Model G-1159A airplane modified
by AeroMech Incorporated. It is not a rule of general applicability and
affects only the applicant who 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 Special Conditions
Therefore, under the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the supplemental type certification basis for the Gulfstream Aerospace
Corporation Model G-1159A airplane modified by AeroMech Incorporated.
1. Protection from Unwanted Effects of High-Intensity Radiated
Fields (HIRF). Each electrical and electronic system that performs
critical functions must be designed and installed to ensure that the
operation and operational capability of these systems to perform
critical functions are not adversely affected when the airplane is
exposed to high-intensity radiated fields.
2. For the purpose of these special conditions, 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 December 29, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-197 Filed 1-9-07; 8:45 am]
BILLING CODE 4910-13-P
