Special Conditions: Learjet 25, 25A, 25B, 25C, 25D, and 25F Airplanes; High-Intensity Radiated Fields (HIRF), 70646-70648 [E6-20276]
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Federal Register / Vol. 71, No. 234 / Wednesday, December 6, 2006 / Rules and Regulations
partnership, association, or corporation,
service may similarly be made by
service on any member of the
partnership or any officer, employee, or
agent of the association or corporation.
Interpretive Rules
§ 33.50
Apples for processing.
The terms ‘‘apples for processing’’ as
used in § 33.12 of this part apply only
and is restricted to packages of apples
which were originally packaged for
processing and marked ‘‘Cannery’’ as
required by § 33.12(c) of this part.
Packages of apples not so originally
packaged and marked are not eligible for
certification as ‘‘apples for processing’’
for purposes of this part.
§ 33.60 OMB control number assigned
pursuant to the Paperwork Reduction Act.
The OMB control number assigned
pursuant to the Paperwork Reduction
Act for this part is OMB No. 0581–0143.
Dated: December 1, 2006.
Lloyd C. Day,
Administrator, Agricultural Marketing
Service.
[FR Doc. E6–20659 Filed 12–5–06; 8:45 am]
BILLING CODE 3410–02–P
DEPARTMENT OF AGRICULTURE
Agricultural Marketing Service
7 CFR Part 981
[Docket No. FV06–981–2 C]
Almonds Grown in California; Changes
to Incoming Quality Control
Requirements; Correction
Agricultural Marketing Service,
USDA.
ACTION: Final rule; correction.
AGENCY:
The Agricultural Marketing
Service (AMS) published in the Federal
Register on November 8, 2006, a
document concerning quality control
requirements under the California
almond marketing order. Language was
inadvertently omitted in the regulatory
text to specify that the changes apply to
all almonds received by handlers
beginning August 1, 2006.
DATES: Effective Date: December 6, 2006.
FOR FURTHER INFORMATION CONTACT:
Maureen T. Pello, Assistant Regional
Manager, or Kurt J. Kimmel, Regional
Manager, California Marketing Field
Office, Marketing Order Administration
Branch, Fruit and Vegetable Programs,
AMS, USDA, telephone: (559) 487–
5901, Fax: (559) 487–5906, or e-mail:
Maureen.Pello@usda.gov, or
Kurt.Kimmel@usda.gov.
mstockstill on PROD1PC61 with RULES
SUMMARY:
VerDate Aug<31>2005
15:34 Dec 05, 2006
Jkt 211001
The AMS
published a document in the Federal
Register on November 8, 2006 (71 FR
65373) that inadvertently omitted
language in the regulatory text to
indicate that the changes apply to all
almonds received by handlers beginning
August 1, 2006. This document corrects
the regulatory text.
SUPPLEMENTARY INFORMATION:
List of Subjects in 7 CFR Part 981
Almonds, Marketing agreements,
Nuts, Reporting and recordkeeping
requirements.
I Accordingly, 7 CFR part 981 is
corrected by making the following
correcting amendments:
PART 981—ALMONDS GROWN IN
CALIFORNIA
1. The authority citation for 7 CFR
part 981 continues to read as follows:
I
Authority: 7 U.S.C. 601–674
2. In § 981.442 revise the first
sentence of paragraph (a)(4)(i) and the
11th sentence in paragraph (a)(5) to read
as follows:
I
§ 981.442
Quality Control.
(a) * * *
(4) Disposition obligation. (i)
Beginning August 1, 2006, the weight of
inedible kernels in excess of 0.50
percent of kernel weight reported to the
Board of any variety received by a
handler shall constitute that handler’s
disposition obligation. * * *
(5) * * * Beginning August 1, 2006,
at least 50 percent of a handler’s total
crop year inedible disposition obligation
shall be satisfied with dispositions
consisting of inedible kernels as defined
in § 981.408: Provided, That this 50
percent requirement shall not apply to
handlers with total annual obligations of
less than 1,000 pounds. * * *
Dated: December 1, 2006.
Lloyd C. Day,
Administrator, Agricultural Marketing
Service.
[FR Doc. 06–9545 Filed 12–1–06; 2:50 pm]
BILLING CODE 3410–02–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM360; Special Conditions No.
25–337–SC]
Special Conditions: Learjet 25, 25A,
25B, 25C, 25D, and 25F Airplanes;
High-Intensity Radiated Fields (HIRF)
Federal Aviation
Administration (FAA), DOT.
AGENCY:
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Final special conditions; request
for comments.
ACTION:
SUMMARY: The FAA issues these special
conditions for Learjet 25, 25A, 25B, 25C,
25D, and 25F airplanes modified by
Envoy Aerospace, LLC. These modified
airplanes will have novel or unusual
design features when compared with the
state of technology envisioned in the
airworthiness standards for transport
category airplanes. The modification
consists of installing Universal Avionics
EFI–890 Electronic Flight Displays and
Rockwell Collins AHS–1000A Attitude
Heading Reference Systems. The
applicable airworthiness regulations do
not contain adequate or appropriate
safety standards for protecting these
systems from 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 for these
special conditions is November 13,
2006. We must receive your comments
on or before January 5, 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. NM360, 1601
Lind Avenue, SW., Renton, Washington
98057–3356. You must mark your
comments Docket No. NM360.
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,
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Federal Register / Vol. 71, No. 234 / Wednesday, December 6, 2006 / Rules and Regulations
airplanes includes 14 CFR Part 25, as
amended by 25–2 and 25–4, and FAA
Special Conditions as set forth in a letter
to Learjet dated March 1, 1967. For
further details refer to Type Certificate
No. A10CE.
If the Administrator finds that the
applicable airworthiness regulations
(part 25, as amended) do not contain
adequate or appropriate safety standards
for the Learjet 25, 25A, 25B, 25C, 25D,
and 25F airplanes because of a novel or
unusual design feature, special
conditions are prescribed under the
provisions of § 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, the Learjet 25, 25A, 25B,
25C, 25D, and 25F airplanes 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.
Background
On June 3, 2006, Envoy Aerospace,
LLC of Naperville, Illinois, applied to
the FAA Chicago Aircraft Certification
Office for a supplemental type
certificate to modify Learjet Model 25,
25A, 25B, 25C, 25D, and 25F airplanes
approved under Type Certificate No.
A10CE. These are transport category
airplanes powered by two turbofan
engines with maximum takeoff weights
of up to 15,000 pounds. The airplanes
operate with a 2-pilot crew and can seat
up to 8 passengers. The proposed
modification incorporates the
installation of Universal Avionics EFI–
890 Electronic Flight Displays and
Rockwell Collins AHS–1000A Attitude
Heading Reference Systems. These
systems have a potential to be
vulnerable to high-intensity radiated
fields (HIRF) external to the airplane.
mstockstill on PROD1PC61 with RULES
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
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.
Novel or Unusual Design Features
Type Certification Basis
Under provisions of 14 CFR 21.101,
Envoy Aerospace, LLC must show that
the Learjet 25, 25A, 25B, 25C, 25D, and
25F airplanes, as changed, continue to
meet the applicable provisions of the
regulations incorporated by reference in
Type Certificate No. A10CE 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 original type
certification basis for the modified
Learjet 25, 25A, 25B, 25C, 25D, and 25F
VerDate Aug<31>2005
15:34 Dec 05, 2006
Jkt 211001
As noted earlier, the Learjet 25, 25A,
25B, 25C, 25D, and 25F airplanes
modified by Envoy Aerospace, LLC will
incorporate digital flight display and
attitude reference systems 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 these system
are considered to be novel or unusual
design features.
Discussion
As previously stated, there is no
specific regulation that addresses
protection for electrical and electronic
systems from HIRF. Increased power
levels from radio frequency 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 Learjet 25, 25A, 25B, 25C, 25D,
and 25F airplanes modified by Envoy
Aerospace, LLC. These special
conditions require that new avionics/
electronics and electrical systems that
perform critical functions be designed
and installed to preclude component
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70647
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 an 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 environment 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 ...........
50
50
50
100
50
50
100
100
700
700
2000
3000
3000
1000
3000
2000
600
Average
50
50
50
100
50
50
100
100
50
100
200
200
200
200
300
200
200
The field strengths are expressed in terms
of peak of the root-mean-square (rms) over
the complete modulation period.
The environment 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.
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70648
Federal Register / Vol. 71, No. 234 / Wednesday, December 6, 2006 / Rules and Regulations
Applicability
DEPARTMENT OF TRANSPORTATION
These special conditions are
applicable to Learjet 25, 25A, 25B, 25C,
25D, and 25F airplanes modified by
Envoy Aerospace, LLC. Should Envoy
Aerospace, LLC apply at a later date for
a supplemental type certificate to
modify any other model included on
Type Certificate No. A10CE to
incorporate the same or similar novel or
unusual design feature, these special
conditions would apply to that model as
well under provisions of § 21.101.
Federal Aviation Administration
Conclusion
This action affects only certain novel
or unusual design features on Learjet 25,
25A, 25B, 25C, 25D, and 25F airplanes
modified by Envoy Aerospace, LLC. It is
not a rule of general applicability and
affects only the applicant which applied
to the FAA for approval of these design
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:
I
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 Learjet 25,
25A, 25B, 25C, 25D, and 25F airplanes
modified by Envoy Aerospace, LLC.
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
continued safe flight and landing of the
airplane.
mstockstill on PROD1PC61 with RULES
I
Issued in Renton, Washington, on
November 13, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. E6–20276 Filed 12–5–06; 8:45 am]
BILLING CODE 4910–13–P
VerDate Aug<31>2005
15:34 Dec 05, 2006
Jkt 211001
14 CFR Part 39
[Docket No. FAA–2006–24696; Directorate
Identifier 2006–NM–038–AD]
RIN 2120–AA64
Airworthiness Directives; Empresa
Brasileira de Aeronautica S.A.
(EMBRAER) Model EMB–145, –145ER,
–145MR, –145LR, –145XR, –145MP, and
–145EP Airplanes; and Model EMB–
135BJ, –135ER, –135KE, –135KL, and
–135LR Airplanes
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Supplemental notice of
proposed rulemaking (NPRM);
reopening of comment period.
AGENCY:
SUMMARY: The FAA is revising an earlier
NPRM for an airworthiness directive
(AD) that applies to certain EMBRAER
Model EMB–145, –145ER, –145MR,
–145LR, –145XR, –145MP, and –145EP
airplanes. The original NPRM would
have required replacing the electrical
bonding clamps inside the fuel tanks
and adjacent areas. The original NPRM
resulted from a report of the failure of
a fitting clamp of an electrical bonding
cable for the fuel tubing. This action
revises the original NPRM by adding
airplanes to the applicability. We are
proposing this supplemental NPRM to
prevent loss of bonding protection in
the interior of the fuel tanks or adjacent
areas, and a consequent potential source
of ignition in a fuel tank and possible
fire or explosion.
DATES: We must receive comments on
this supplemental NPRM by January 2,
2007.
ADDRESSES: Use one of the following
addresses to submit comments on this
supplemental NPRM.
• DOT Docket Web site: Go to
https://dms.dot.gov and follow the
instructions for sending your comments
electronically.
• Government-wide rulemaking Web
site: Go to https://www.regulations.gov
and follow the instructions for sending
your comments electronically.
• Mail: Docket Management Facility;
U.S. Department of Transportation, 400
Seventh Street, SW., Nassif Building,
Room PL–401, Washington, DC 20590.
• Fax: (202) 493–2251.
• Hand Delivery: Room PL–401 on
the plaza level of the Nassif Building,
400 Seventh Street SW., Washington,
DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
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Contact Empresa Brasileira de
Aeronautica S.A. (EMBRAER), P.O. Box
343—CEP 12.225, Sao Jose dos
Campos—SP, Brazil, for service
information identified in this proposed
AD.
FOR FURTHER INFORMATION CONTACT: Dan
Rodina, Aerospace Engineer,
International Branch, ANM–116,
Transport Airplane Directorate, FAA,
1601 Lind Avenue, SW., Renton,
Washington 98057–3356; telephone
(425) 227–2125; fax (425) 227–1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any relevant
written data, views, or arguments
regarding this supplemental NPRM.
Send your comments to an address
listed in the ADDRESSES section. Include
the docket number ‘‘Docket No. FAA–
2006–24696; Directorate Identifier
2006–NM–038–AD’’ at the beginning of
your comments. We specifically invite
comments on the overall regulatory,
economic, environmental, and energy
aspects of this supplemental NPRM. We
will consider all comments received by
the closing date and may amend this
supplemental NPRM in light of those
comments.
We will post all comments submitted,
without change, to https://dms.dot.gov,
including any personal information you
provide. We will also post a report
summarizing each substantive verbal
contact with FAA personnel concerning
this supplemental NPRM. Using the
search function of that Web site, anyone
can find and read the comments in any
of our dockets, including the name of
the individual who sent the comment
(or signed the comment on behalf of an
association, business, labor union, etc.).
You may review the DOT’s complete
Privacy Act Statement in the Federal
Register published on April 11, 2000
(65 FR 19477–78), or you may visit
https://dms.dot.gov.
Examining the Docket
You may examine the 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 in the Nassif Building at the DOT
street address stated in ADDRESSES.
Comments will be available in the AD
docket shortly after the Docket
Management System receives them.
Discussion
We proposed to amend 14 CFR part
39 with a notice of proposed rulemaking
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]]>Agencies
[Federal Register Volume 71, Number 234 (Wednesday, December 6, 2006)]
[Rules and Regulations]
[Pages 70646-70648]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E6-20276]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM360; Special Conditions No. 25-337-SC]
Special Conditions: Learjet 25, 25A, 25B, 25C, 25D, and 25F
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 Learjet 25, 25A,
25B, 25C, 25D, and 25F airplanes modified by Envoy Aerospace, LLC.
These modified airplanes will have novel or unusual design features
when compared with the state of technology envisioned in the
airworthiness standards for transport category airplanes. The
modification consists of installing Universal Avionics EFI-890
Electronic Flight Displays and Rockwell Collins AHS-1000A Attitude
Heading Reference Systems. The applicable airworthiness regulations do
not contain adequate or appropriate safety standards for protecting
these systems from 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 for these special conditions is November 13,
2006. We must receive your comments on or before January 5, 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. NM360, 1601
Lind Avenue, SW., Renton, Washington 98057-3356. You must mark your
comments Docket No. NM360.
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,
[[Page 70647]]
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 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 June 3, 2006, Envoy Aerospace, LLC of Naperville, Illinois,
applied to the FAA Chicago Aircraft Certification Office for a
supplemental type certificate to modify Learjet Model 25, 25A, 25B,
25C, 25D, and 25F airplanes approved under Type Certificate No. A10CE.
These are transport category airplanes powered by two turbofan engines
with maximum takeoff weights of up to 15,000 pounds. The airplanes
operate with a 2-pilot crew and can seat up to 8 passengers. The
proposed modification incorporates the installation of Universal
Avionics EFI-890 Electronic Flight Displays and Rockwell Collins AHS-
1000A Attitude Heading Reference Systems. These systems have a
potential to be vulnerable to high-intensity radiated fields (HIRF)
external to the airplane.
Type Certification Basis
Under provisions of 14 CFR 21.101, Envoy Aerospace, LLC must show
that the Learjet 25, 25A, 25B, 25C, 25D, and 25F airplanes, as changed,
continue to meet the applicable provisions of the regulations
incorporated by reference in Type Certificate No. A10CE 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 original type certification basis for the
modified Learjet 25, 25A, 25B, 25C, 25D, and 25F airplanes includes 14
CFR Part 25, as amended by 25-2 and 25-4, and FAA Special Conditions as
set forth in a letter to Learjet dated March 1, 1967. For further
details refer to Type Certificate No. A10CE.
If the Administrator finds that the applicable airworthiness
regulations (part 25, as amended) do not contain adequate or
appropriate safety standards for the Learjet 25, 25A, 25B, 25C, 25D,
and 25F airplanes because of a novel or unusual design feature, special
conditions are prescribed under the provisions of Sec. 21.16.
In addition to the applicable airworthiness regulations and special
conditions, the Learjet 25, 25A, 25B, 25C, 25D, and 25F airplanes 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, the Learjet 25, 25A, 25B, 25C, 25D, and 25F
airplanes modified by Envoy Aerospace, LLC will incorporate digital
flight display and attitude reference systems 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 these system are considered to be novel or unusual design features.
Discussion
As previously stated, there is no specific regulation that
addresses protection for electrical and electronic systems from HIRF.
Increased power levels from radio frequency 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 Learjet 25, 25A, 25B, 25C, 25D, and 25F
airplanes modified by Envoy Aerospace, LLC. 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 an 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 environment 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 environment 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.
[[Page 70648]]
Applicability
These special conditions are applicable to Learjet 25, 25A, 25B,
25C, 25D, and 25F airplanes modified by Envoy Aerospace, LLC. Should
Envoy Aerospace, LLC apply at a later date for a supplemental type
certificate to modify any other model included on Type Certificate No.
A10CE to incorporate the same or similar novel or unusual design
feature, these special conditions would apply to that model as well
under provisions of Sec. 21.101.
Conclusion
This action affects only certain novel or unusual design features
on Learjet 25, 25A, 25B, 25C, 25D, and 25F airplanes modified by Envoy
Aerospace, LLC. It is not a rule of general applicability and affects
only the applicant which applied to the FAA for approval of these
design features on the airplane.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
0
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
The Special Conditions
0
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 Learjet 25, 25A, 25B, 25C, 25D, and
25F airplanes modified by Envoy Aerospace, LLC.
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 continued safe flight and
landing of the airplane.
Issued in Renton, Washington, on November 13, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-20276 Filed 12-5-06; 8:45 am]
BILLING CODE 4910-13-P
