Special Conditions; Dual Innovative Solutions & Support Electronic Flight Instrument Systems (EFIS) Installation in Pilatus PC-12, PC-12/45, and PC-12/47; Protection of Systems for High Intensity Radiated Fields (HIRF), 28764-28766 [06-4624]
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28764
Federal Register / Vol. 71, No. 96 / Thursday, May 18, 2006 / Rules and Regulations
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. CE243, Special Condition 23–
183–SC]
Special Conditions; Dual Innovative
Solutions & Support Electronic Flight
Instrument Systems (EFIS) Installation
in Pilatus PC–12, PC–12/45, and PC–
12/47; Protection of Systems for High
Intensity Radiated Fields (HIRF)
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
rmajette on PROD1PC67 with RULES
AGENCY:
SUMMARY: These special conditions are
issued to Innovative Solutions &
Support (IS&S), 720 Pennsylvania Drive,
Exton, PA 19341–1129, for a
Supplemental Type Certificate for the
Pilatus PC–12, PC–12/45, and PC–12/47
airplanes. These airplanes will have
novel and unusual design features when
compared to the state of technology
envisaged in the applicable
airworthiness standards. These novel
and unusual design features include the
installation of two 12″ x 9″ Integrated
Flat Panel Display (IFPD) Electronic
Flight Instrument Systems (EFIS),
manufactured by IS&S, and components
associated with this display system. The
applicable regulations do not contain
adequate or appropriate airworthiness
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
the airworthiness standards applicable
to these airplanes.
DATES: The effective date of these
special conditions is May 10, 2006.
Comments must be received on or
before June 19, 2006.
ADDRESSES: Comments may be mailed
in duplicate to: Federal Aviation
Administration, Regional Counsel,
ACE–7, Attention: Rules Docket Clerk,
Docket No. CE243, Room 506, 901
Locust, Kansas City, Missouri 64106. All
comments must be marked: Docket No.
CE243. Comments may be inspected in
the Rules Docket weekdays, except
Federal holidays, between 7:30 a.m. and
4 p.m.
FOR FURTHER INFORMATION CONTACT: Wes
Ryan, Aerospace Engineer, Standards
Office (ACE–110), Small Airplane
Directorate, Aircraft Certification
Service, Federal Aviation
VerDate Aug<31>2005
15:00 May 17, 2006
Jkt 208001
Administration, 901 Locust, Room 301,
Kansas City, Missouri 64106; telephone
(816) 329–4123.
SUPPLEMENTARY INFORMATION: The FAA
has determined that notice and
opportunity for prior public comment
hereon are impracticable because 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
Interested persons are invited to
submit such written data, views, or
arguments, as they may desire.
Communications should identify the
regulatory docket or notice number and
be submitted in duplicate to the address
specified above. All communications
received on or before the closing date
for comments will be considered by the
Administrator. The special conditions
may be changed in light of the
comments received. All comments
received will be available in the Rules
Docket for examination by interested
persons, both before and after the
closing date for comments. A report
summarizing each substantive public
contact with FAA personnel concerning
this rulemaking will be filed in the
docket. Commenters wishing the FAA to
acknowledge receipt of their comments
submitted in response to this notice
must include a self-addressed, stamped
postcard on which the following
statement is made: ‘‘Comments to
Docket No. CE243.’’ The postcard will
be date stamped and returned to the
commenter.
Background
In early February 2006, IS&S made an
application to the FAA for a new
Supplemental Type Certificate (STC) for
the Pilatus PC–12, PC–12/45, and PC–
12/47 airplanes, which are currently
approved under TC No. A78EU. The
proposed modification incorporates
novel or unusual design features that are
vulnerable to HIRF external to the
airplane.
Type Certification Basis
Under the provisions of 14 CFR part
21, § 21.101, IS&S must show that the
Pilatus PC–12, PC–12/45, and PC–12/47
aircraft meet the provisions of the
original certification basis for each
model, as listed on the Type Data Sheet
A78EU, and the additional provisions &
applicable regulations in effect on the
date of application for this
Supplemental Type Change. The
additional systems related provisions
PO 00000
Frm 00006
Fmt 4700
Sfmt 4700
that cover the EFIS installation include:
§ 23.1301, § 23.1309, § 23.1311,
§ 23.1321, § 23.1322, § 23.1323,
§ 23.1331, § 23.1353, and § 23.1357 at
the amendment level appropriate for the
application date; exemptions, if any;
and the special conditions adopted by
this rulemaking action. Additional
information regarding the certification
basis for this STC is available from the
applicant.
Discussion
If the Administrator finds that the
applicable airworthiness standards do
not contain adequate or appropriate
safety standards because of novel or
unusual design features of an airplane,
special conditions are prescribed under
the provisions of § 21.16.
Special conditions, as appropriate, as
defined in § 11.19, are issued in
accordance with § 11.38 after public
notice and become part of the type
certification basis in accordance with
§ 21.101(b)(2).
Special conditions are initially
applicable to the model for which they
are issued. Should the applicant apply
for a supplemental type certificate to
modify any other model already
included on the same type certificate to
incorporate the same novel or unusual
design feature, the special conditions
would also apply to the other model
under the provisions of § 21.101.
Novel or Unusual Design Features
IS&S plans to incorporate certain
novel and unusual design features into
an airplane for which the airworthiness
standards do not contain adequate or
appropriate safety standards for
protection from the effects of HIRF.
These features include dual EFIS
systems and associated components,
potentially susceptible to the HIRF
environment that were not envisaged by
the existing regulations for this type of
airplane.
Protection of Systems From High
Intensity Radiated Fields (HIRF)
Recent advances in technology have
given rise to the application in aircraft
designs of advanced electrical and
electronic systems that perform
functions required for continued safe
flight and landing. Due to the use of
sensitive solid-state advanced
components in analog and digital
electronics circuits, these advanced
systems are readily responsive to the
transient effects of induced electrical
current and voltage caused by the HIRF.
The HIRF can degrade electronic
systems performance by damaging
components or upsetting system
functions.
E:\FR\FM\18MYR1.SGM
18MYR1
Federal Register / Vol. 71, No. 96 / Thursday, May 18, 2006 / Rules and Regulations
Furthermore, the HIRF environment
has undergone a transformation that was
not foreseen when the current
requirements were developed. Higher
energy levels are radiated from
transmitters that are used for radar,
radio, and television. Also, the number
of transmitters has increased
significantly. There is also uncertainty
concerning the effectiveness of airframe
shielding for HIRF. Furthermore,
coupling to cockpit-installed equipment
through the cockpit window apertures is
undefined.
The combined effect of the
technological advances in airplane
design and the changing environment
has resulted in an increased level of
vulnerability of electrical and electronic
systems required for the continued safe
flight and landing of the airplane.
Effective measures against the effects of
exposure to HIRF must be provided by
the design and installation of these
systems. The accepted maximum energy
levels in which civilian airplane system
installations must be capable of
operating safely are based on surveys
and analysis of existing radio frequency
emitters. These special conditions
require that the airplane be evaluated
under these energy levels for the
protection of the electronic system and
its associated wiring harness. These
external threat levels, which are lower
than previous required values, are
28765
believed to represent the worst case to
which an airplane would be exposed in
the operating environment.
These special conditions require
qualification of systems that perform
critical functions, as installed in aircraft,
to the defined HIRF environment in
paragraph 1 or, as an option to a fixed
value using laboratory tests, in
paragraph 2, as follows:
(1) The applicant may demonstrate
that the operation and operational
capability of the installed electrical and
electronic systems that perform critical
functions are not adversely affected
when the aircraft is exposed to the HIRF
environment defined below:
Field strength (volts per meter)
Frequency
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 root-mean-square (rms) values.
rmajette on PROD1PC67 with RULES
or,
(2) The applicant may demonstrate by
a system test and analysis that the
electrical and electronic systems that
perform critical functions can withstand
a minimum threat of 100 volts per
meter, electrical field strength, from 10
kHz to 18 GHz. When using this test to
show compliance with the HIRF
requirements, no credit is given for
signal attenuation due to installation.
A preliminary hazard analysis must
be performed by the applicant, for
approval by the FAA, to identify either
electrical or electronic systems that
perform critical functions. The term
‘‘critical’’ refers to functions, whose
failure would contribute to, or cause, a
failure condition that would prevent the
continued safe flight and landing of the
airplane. The systems identified by the
hazard analysis that perform critical
functions are candidates for the
application of HIRF requirements. A
system may perform both critical and
non-critical functions. Primary
VerDate Aug<31>2005
15:00 May 17, 2006
Jkt 208001
electronic flight display systems, and
their associated components, perform
critical functions such as attitude,
altitude, and airspeed indication. The
HIRF requirements apply only to critical
functions.
Compliance with HIRF requirements
may be demonstrated by tests, analysis,
models, similarity with existing
systems, or any combination of these.
Service experience alone is not
acceptable since normal flight
operations may not include an exposure
to the HIRF environment. Reliance on a
system with similar design features for
redundancy as a means of protection
against the effects of external HIRF is
generally insufficient since all elements
of a redundant system are likely to be
exposed to the fields concurrently.
Applicability
As discussed above, these special
conditions are applicable to the Pilatus
PC–12, PC–12/45, and PC–12/47
airplanes. Should IS&S apply at a later
date for a supplemental type certificate
PO 00000
Frm 00007
Fmt 4700
Sfmt 4700
to modify any other model on the same
type certificate to incorporate the same
novel or unusual design feature, the
special conditions would apply to that
model as well under the provisions of
§ 21.101.
Conclusion
This action affects only certain novel
or unusual design features on one model
of airplane. 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.
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. For this reason, and
because a delay would significantly
affect the certification of the airplane,
which is imminent, the FAA has
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18MYR1
28766
Federal Register / Vol. 71, No. 96 / Thursday, May 18, 2006 / Rules and Regulations
determined that prior public notice and
comment are unnecessary and
impracticable, and good cause exists for
adopting these special conditions upon
issuance. 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.
Aircraft, Aviation safety, Signs and
symbols.
Authority: 49 U.S.C. 106(g), 40113 and
44701; 14 CFR 21.16 and 21.101; and 14 CFR
11.38 and 11.19.
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 Pilatus PC–12,
PC–12/45, and PC–12/47 airplanes
modified by IS&S to add dual EFIS
installations.
1. Protection of Electrical and
Electronic Systems From High Intensity
Radiated Fields (HIRF). Each system
that performs critical functions must be
designed and installed to ensure that the
operations, and operational capabilities
of these systems to perform critical
functions, are not adversely affected
when the airplane is exposed to high
intensity radiated electromagnetic fields
external to the airplane.
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 Kansas City, Missouri on May 10,
2006.
David R. Showers,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 06–4624 Filed 5–17–06; 8:45 am]
rmajette on PROD1PC67 with RULES
Jkt 208001
You may examine the airworthiness
directive (AD) docket on the Internet at
https://dms.dot.gov or in person at the
Docket Management Facility office
between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
The Docket Management Facility office
(telephone (800) 647–5227) is located on
the plaza level of the Nassif Building at
the street address stated in the
ADDRESSES section.
14 CFR Part 39
[Docket No. FAA–2005–21028; Directorate
Identifier 2004–NM–238–AD; Amendment
39–14601; AD 2006–10–17]
RIN 2120–AA64
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
The authority citation for these
special conditions is as follows:
15:00 May 17, 2006
Federal Aviation Administration
AGENCY:
Citation
VerDate Aug<31>2005
Examining the Docket
Airworthiness Directives; Boeing
Model 737–600, –700, –700C, –800, and
–900 Series Airplanes
List of Subjects in 14 CFR Part 23
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
SUMMARY: The FAA is adopting a new
airworthiness directive (AD) for certain
Boeing Model 737–600, –700, –700C,
–800, and –900 series airplanes. This
AD requires replacing brackets that hold
the P5 panel to the airplane structure,
the standby compass bracket assembly,
the generator drive and standby power
module, and the air conditioning
module. This AD also requires, among
other actions, inspecting for wire length
and for damage of the connectors and
the wire bundles, and doing applicable
corrective actions if necessary. This AD
results from an electrical burning smell
in the flight compartment. We are
issuing this AD to prevent wire bundles
from contacting the overhead dripshield
panel and modules in the P5 overhead
panel, which could result in electrical
arcing and shorting of the electrical
connector and consequent loss of
several critical systems essential for safe
flight.
DATES: This AD becomes effective June
22, 2006.
The Director of the Federal Register
approved the incorporation by reference
of certain publications listed in the AD
as of June 22, 2006.
ADDRESSES: You may examine the AD
docket on the Internet at https://
dms.dot.gov or in person at the Docket
Management Facility, U.S. Department
of Transportation, 400 Seventh Street,
SW., Nassif Building, Room PL–401,
Washington, DC.
Contact Boeing Commercial
Airplanes, P.O. Box 3707, Seattle,
Washington 98124–2207, for service
information identified in this AD.
FOR FURTHER INFORMATION CONTACT:
Binh Tran, Aerospace Engineer, Systems
and Equipment Branch, ANM–130S,
FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton,
Washington 98055–4056; telephone
(425) 917–6485; fax (425) 917–6590.
SUPPLEMENTARY INFORMATION:
PO 00000
Frm 00008
Fmt 4700
Sfmt 4700
Discussion
The FAA issued a notice of proposed
rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would
apply to certain Boeing Model 737–600,
–700, –700C, –800, and –900 series
airplanes. That NPRM was published in
the Federal Register on April 27, 2005
(70 FR 21689). That NPRM proposed to
require replacing brackets that hold the
P5 panel to the airplane structure, the
standby compass bracket assembly, the
generator drive and standby power
module, and the air conditioning
module. That NPRM also proposed to
require, among other actions, inspecting
for wire length and for damage of the
connectors and the wire bundles, and
doing applicable corrective actions if
necessary.
New Relevant Service Information
Since the issuance of the NPRM, we
have reviewed Revision 2 of Boeing
Service Bulletin 737–24A1141, dated
December 1, 2005 (Revision 1 of the
service bulletin was referenced in the
NPRM as the appropriate source of
service information for doing certain
proposed actions). Revision 2 updates
multiple figures to correct typographical
errors in the graphics or in the task or
flag note tables. Revision 2 also moves
a certain group of airplanes from one
figure to another. The procedures in
Revision 2 are essentially identical to
those in Revision 1. No more work is
necessary on airplanes changed as
shown in Revision 1 of the service
bulletin. Therefore, we have revised
paragraph (f) of this AD to refer to
Revision 2 as the appropriate source of
service information for doing the
required inspection, replacements,
wiring changes, and corrective actions if
necessary. We also have revised the
applicability to refer to Revision 2 as the
appropriate source of service
information for determining the affected
airplanes. In addition, we have added a
new paragraph (g) to the AD (and
redesignated subsequent paragraphs) to
give operators credit for doing the
actions required by paragraph (f) before
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18MYR1
]]>Agencies
[Federal Register Volume 71, Number 96 (Thursday, May 18, 2006)]
[Rules and Regulations]
[Pages 28764-28766]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 06-4624]
[[Page 28764]]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. CE243, Special Condition 23-183-SC]
Special Conditions; Dual Innovative Solutions & Support
Electronic Flight Instrument Systems (EFIS) Installation in Pilatus PC-
12, PC-12/45, and PC-12/47; Protection of Systems for High Intensity
Radiated Fields (HIRF)
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued to Innovative Solutions &
Support (IS&S), 720 Pennsylvania Drive, Exton, PA 19341-1129, for a
Supplemental Type Certificate for the Pilatus PC-12, PC-12/45, and PC-
12/47 airplanes. These airplanes will have novel and unusual design
features when compared to the state of technology envisaged in the
applicable airworthiness standards. These novel and unusual design
features include the installation of two 12'' x 9'' Integrated Flat
Panel Display (IFPD) Electronic Flight Instrument Systems (EFIS),
manufactured by IS&S, and components associated with this display
system. The applicable regulations do not contain adequate or
appropriate airworthiness 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 the airworthiness standards applicable to these
airplanes.
DATES: The effective date of these special conditions is May 10, 2006.
Comments must be received on or before June 19, 2006.
ADDRESSES: Comments may be mailed in duplicate to: Federal Aviation
Administration, Regional Counsel, ACE-7, Attention: Rules Docket Clerk,
Docket No. CE243, Room 506, 901 Locust, Kansas City, Missouri 64106.
All comments must be marked: Docket No. CE243. Comments may be
inspected in the Rules Docket weekdays, except Federal holidays,
between 7:30 a.m. and 4 p.m.
FOR FURTHER INFORMATION CONTACT: Wes Ryan, Aerospace Engineer,
Standards Office (ACE-110), Small Airplane Directorate, Aircraft
Certification Service, Federal Aviation Administration, 901 Locust,
Room 301, Kansas City, Missouri 64106; telephone (816) 329-4123.
SUPPLEMENTARY INFORMATION: The FAA has determined that notice and
opportunity for prior public comment hereon are impracticable because
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
Interested persons are invited to submit such written data, views,
or arguments, as they may desire. Communications should identify the
regulatory docket or notice number and be submitted in duplicate to the
address specified above. All communications received on or before the
closing date for comments will be considered by the Administrator. The
special conditions may be changed in light of the comments received.
All comments received will be available in the Rules Docket for
examination by interested persons, both before and after the closing
date for comments. A report summarizing each substantive public contact
with FAA personnel concerning this rulemaking will be filed in the
docket. Commenters wishing the FAA to acknowledge receipt of their
comments submitted in response to this notice must include a self-
addressed, stamped postcard on which the following statement is made:
``Comments to Docket No. CE243.'' The postcard will be date stamped and
returned to the commenter.
Background
In early February 2006, IS&S made an application to the FAA for a
new Supplemental Type Certificate (STC) for the Pilatus PC-12, PC-12/
45, and PC-12/47 airplanes, which are currently approved under TC No.
A78EU. The proposed modification incorporates novel or unusual design
features that are vulnerable to HIRF external to the airplane.
Type Certification Basis
Under the provisions of 14 CFR part 21, Sec. 21.101, IS&S must
show that the Pilatus PC-12, PC-12/45, and PC-12/47 aircraft meet the
provisions of the original certification basis for each model, as
listed on the Type Data Sheet A78EU, and the additional provisions &
applicable regulations in effect on the date of application for this
Supplemental Type Change. The additional systems related provisions
that cover the EFIS installation include: Sec. 23.1301, Sec. 23.1309,
Sec. 23.1311, Sec. 23.1321, Sec. 23.1322, Sec. 23.1323, Sec.
23.1331, Sec. 23.1353, and Sec. 23.1357 at the amendment level
appropriate for the application date; exemptions, if any; and the
special conditions adopted by this rulemaking action. Additional
information regarding the certification basis for this STC is available
from the applicant.
Discussion
If the Administrator finds that the applicable airworthiness
standards do not contain adequate or appropriate safety standards
because of novel or unusual design features of an airplane, special
conditions are prescribed under the provisions of Sec. 21.16.
Special conditions, as appropriate, as defined in Sec. 11.19, are
issued in accordance with Sec. 11.38 after public notice and become
part of the type certification basis in accordance with Sec.
21.101(b)(2).
Special conditions are initially applicable to the model for which
they are issued. Should the applicant apply for a supplemental type
certificate to modify any other model already included on the same type
certificate to incorporate the same novel or unusual design feature,
the special conditions would also apply to the other model under the
provisions of Sec. 21.101.
Novel or Unusual Design Features
IS&S plans to incorporate certain novel and unusual design features
into an airplane for which the airworthiness standards do not contain
adequate or appropriate safety standards for protection from the
effects of HIRF. These features include dual EFIS systems and
associated components, potentially susceptible to the HIRF environment
that were not envisaged by the existing regulations for this type of
airplane.
Protection of Systems From High Intensity Radiated Fields (HIRF)
Recent advances in technology have given rise to the application in
aircraft designs of advanced electrical and electronic systems that
perform functions required for continued safe flight and landing. Due
to the use of sensitive solid-state advanced components in analog and
digital electronics circuits, these advanced systems are readily
responsive to the transient effects of induced electrical current and
voltage caused by the HIRF. The HIRF can degrade electronic systems
performance by damaging components or upsetting system functions.
[[Page 28765]]
Furthermore, the HIRF environment has undergone a transformation
that was not foreseen when the current requirements were developed.
Higher energy levels are radiated from transmitters that are used for
radar, radio, and television. Also, the number of transmitters has
increased significantly. There is also uncertainty concerning the
effectiveness of airframe shielding for HIRF. Furthermore, coupling to
cockpit-installed equipment through the cockpit window apertures is
undefined.
The combined effect of the technological advances in airplane
design and the changing environment has resulted in an increased level
of vulnerability of electrical and electronic systems required for the
continued safe flight and landing of the airplane. Effective measures
against the effects of exposure to HIRF must be provided by the design
and installation of these systems. The accepted maximum energy levels
in which civilian airplane system installations must be capable of
operating safely are based on surveys and analysis of existing radio
frequency emitters. These special conditions require that the airplane
be evaluated under these energy levels for the protection of the
electronic system and its associated wiring harness. These external
threat levels, which are lower than previous required values, are
believed to represent the worst case to which an airplane would be
exposed in the operating environment.
These special conditions require qualification of systems that
perform critical functions, as installed in aircraft, to the defined
HIRF environment in paragraph 1 or, as an option to a fixed value using
laboratory tests, in paragraph 2, as follows:
(1) The applicant may demonstrate that the operation and
operational capability of the installed electrical and electronic
systems that perform critical functions are not adversely affected when
the aircraft is exposed to the HIRF environment defined below:
------------------------------------------------------------------------
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 root-mean-square
(rms) values.
------------------------------------------------------------------------
or,
(2) The applicant may demonstrate by a system test and analysis
that the electrical and electronic systems that perform critical
functions can withstand a minimum threat of 100 volts per meter,
electrical field strength, from 10 kHz to 18 GHz. When using this test
to show compliance with the HIRF requirements, no credit is given for
signal attenuation due to installation.
A preliminary hazard analysis must be performed by the applicant,
for approval by the FAA, to identify either electrical or electronic
systems that perform critical functions. The term ``critical'' refers
to functions, whose failure would contribute to, or cause, a failure
condition that would prevent the continued safe flight and landing of
the airplane. The systems identified by the hazard analysis that
perform critical functions are candidates for the application of HIRF
requirements. A system may perform both critical and non-critical
functions. Primary electronic flight display systems, and their
associated components, perform critical functions such as attitude,
altitude, and airspeed indication. The HIRF requirements apply only to
critical functions.
Compliance with HIRF requirements may be demonstrated by tests,
analysis, models, similarity with existing systems, or any combination
of these. Service experience alone is not acceptable since normal
flight operations may not include an exposure to the HIRF environment.
Reliance on a system with similar design features for redundancy as a
means of protection against the effects of external HIRF is generally
insufficient since all elements of a redundant system are likely to be
exposed to the fields concurrently.
Applicability
As discussed above, these special conditions are applicable to the
Pilatus PC-12, PC-12/45, and PC-12/47 airplanes. Should IS&S apply at a
later date for a supplemental type certificate to modify any other
model on the same type certificate to incorporate the same novel or
unusual design feature, the special conditions would apply to that
model as well under the provisions of Sec. 21.101.
Conclusion
This action affects only certain novel or unusual design features
on one model of airplane. 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.
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. For this reason, and because a
delay would significantly affect the certification of the airplane,
which is imminent, the FAA has
[[Page 28766]]
determined that prior public notice and comment are unnecessary and
impracticable, and good cause exists for adopting these special
conditions upon issuance. 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 23
Aircraft, Aviation safety, Signs and symbols.
Citation
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113 and 44701; 14 CFR 21.16 and
21.101; and 14 CFR 11.38 and 11.19.
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 Pilatus PC-12, PC-12/45, and PC-
12/47 airplanes modified by IS&S to add dual EFIS installations.
1. Protection of Electrical and Electronic Systems From High
Intensity Radiated Fields (HIRF). Each system that performs critical
functions must be designed and installed to ensure that the operations,
and operational capabilities of these systems to perform critical
functions, are not adversely affected when the airplane is exposed to
high intensity radiated electromagnetic fields external to the
airplane.
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 Kansas City, Missouri on May 10, 2006.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 06-4624 Filed 5-17-06; 8:45 am]
BILLING CODE 4910-13-P
