[Federal Register: May 10, 2005 (Volume 70, Number 89)]
[Rules and Regulations]
[Page 24478-24480]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr10my05-2]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM306; Special Conditions No. 25-287-SC]
Special Conditions: Cessna Aircraft Company Model 650 Citation
III Airplanes; High Intensity Radiated Fields (HIRF)
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
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SUMMARY: These special conditions are issued for Cessna Aircraft
Company Model 650 Citation III airplanes modified by Pro Star Aviation,
LLC. These airplanes will have novel and unusual design features when
compared to the state of technology envisioned in the airworthiness
standards for transport category airplanes. The modification
incorporates the installation of Honeywell Primus Epic Control Display
System (CDS)/Retrofit Electronic Flight Instrument System (EFIS)
system, and a second air data computer. 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 April 27,
2005. Comments must be received on or before June 24, 2005.
ADDRESSES: Comments on these special conditions may be mailed in
duplicate to: Federal Aviation Administration, Transport Airplane
Directorate, Attn: Rules Docket (ANM-113), Docket No. NM306, 1601 Lind
Avenue, SW., Renton, Washington, 98055-4056; or delivered in duplicate
to the Transport Airplane Directorate at the above address. Comments
must be marked: Docket No. NM306.
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, 98055-4056; telephone (425) 227-2799; facsimile (425) 227-
1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
The FAA has determined that notice and opportunity for prior public
comment is impracticable because these procedures would significantly
delay certification of the airplanes and thus 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. The FAA therefore finds that
good cause exists for making these special conditions effective upon
issuance; however, we invite interested persons to participate in this
rulemaking by submitting written comments, data, or views. The most
helpful comments reference a specific portion of the special
conditions, explain the reason for any recommended change, and include
supporting data. We 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
concerning these special conditions. The docket is available for public
inspection 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 in light of the comments received.
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 March 18, 2005, Pro Star Aviation, LLC, Manchester Airport, 5
Industrial Drive, Londonderry, NH 03053, applied for a supplemental
type certificate (STC) to modify Cessna Aircraft Company Model 650
Citation III airplanes. These models are currently approved under Type
Certificate No. A9NM. These Cessna airplane models are small transport
category airplanes powered by two Garrett engines. The Cessna Model 650
airplanes carry a total of 15 people (a pilot, co-pilot, and 13
passengers), and have two wing tanks and a fuselage tank. The
modification incorporates the installation of the Honeywell Primus Epic
CDS/Retrofit EFIS system, EGPWS, and a second air data computer. The
avionics/electronics and electrical systems installed in these
airplanes have the potential to be vulnerable to high-intensity
radiated fields (HIRF) external to the airplanes.
Type Certification Basis
Under the provisions of 14 CFR 21.101, Pro Star Aviation, LLC must
show that the Cessna Aircraft Company Model 650 Citation III airplanes,
as changed, continue to meet the applicable provisions of the
regulations incorporated by reference in Type Certificate No. A9NM, 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 certification
[[Page 24479]]
basis for the Cessna Model 650 airplanes include part 25 of 14 CFR
effective February 1, 1965, as amended by amendments 25-1 through 25-
39; Sec. Sec. 25.901(c) and 25.1199 as amended by Amendments 25-1
through 25-40; Sec. Sec. 25.1309 and 25.1351(d) as amended by
Amendments 25-1 through 25-41; Sec. Sec. 25.177, 25.255, and 25.703 as
amended by Amendments 25-1 through 25-42; Sec. 25.1326 as amended by
Amendments 25-1 through 25-43; Sec. 25.1413 as amended by Amendments
25-1 through 25-44; Sec. Sec. 25.1305 and 25.1529 as amended by
Amendments 25-1 through 25-54. In addition, the certification basis
includes certain special conditions, exemptions, equivalent levels of
safety, or later amended sections of the applicable part 25 that are
not relevant to these special conditions.
If the Administrator finds that the applicable airworthiness
regulations (i.e., part 25, as amended) do not contain adequate or
appropriate safety standards for modified Cessna Aircraft Company Model
650 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 Cessna Model 650 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.
Special conditions, as defined in 14 CFR 11.19, are issued in
accordance with Sec. 11.38, and become part of the type certification
basis in accordance with Sec. 21.101.
Special conditions are initially applicable to the model for which
they are issued. Should Pro Star Aviation LLC apply at a later date for
a supplemental type certificate to modify any other model included on
Type Certificate No. A9NM to incorporate the same novel or unusual
design feature, these special conditions would also apply to the other
model under the provisions of Sec. 21.101.
Novel or Unusual Design Features
As noted earlier, the Cessna Aircraft Company Model 650 airplanes
modified by Pro Star Aviation will incorporate electrical and
electronic systems that will perform critical functions. These systems
may be vulnerable to high-intensity radiated fields external to the
airplane. The current airworthiness standards of part 25 do not contain
adequate or appropriate safety standards for the protection of this
equipment from the adverse effects of HIRF. Accordingly, this system is
considered to be a novel or unusual design feature.
Discussion
There is no specific regulation that addresses protection
requirements for electronic and electrical 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 Cessna Model 650 airplanes modified by
Pro Star Aviation. 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 due to both the direct and indirect effects of HIRF.
High-Intensity Radiated Fields (HIRF)
With the trend toward increased power levels from ground-based
transmitters, and the advent of space and satellite communications,
coupled with electronic command and control of the airplane, the
immunity of critical digital avionics/electronics and electrical
systems to HIRF must be established.
It is not possible to precisely define the HIRF to which the
airplane will be exposed in service. There is also uncertainty
concerning the effectiveness of airframe shielding for HIRF.
Furthermore, coupling of electromagnetic energy to cockpit-installed
equipment through the cockpit window apertures is undefined. Based on
surveys and analysis of existing HIRF emitters, an adequate level of
protection exists when compliance is shown with either HIRF protection
special condition 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. The threat must be applied to the system elements and their
associated wiring harnesses without the benefit of airframe shielding.
b. Demonstration of this level of protection is established through
system tests and analysis.
2. A threat external to the airframe of the field strengths
identified in the table below for the frequency ranges indicated. Both
peak and average field strength components from the table are to be
demonstrated.
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Field strength
(volts per meter)
Frequency -------------------
Peak Average
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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-8GHz.......................................... 1000 200
8 GHz-12 GHz........................................ 3000 300
12 GHz-18 GHz....................................... 2000 200
18 GHz-40 GHz....................................... 600 200
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The field strengths are expressed in terms of peak of the root-mean-
square (rms) over the complete modulation period.
The threat levels identified above are the result of an FAA review
of existing studies on the subject of HIRF, in light of the ongoing
work of the Electromagnetic Effects Harmonization Working Group of the
Aviation Rulemaking Advisory Committee.
Applicability
As discussed above, these special conditions are applicable to the
Cessna Aircraft Company Model 650 airplanes. Should Pro Star Aviation
LLC apply at a later date for a supplemental type certificate to modify
any other model included on Type Certificate No. A9NM to incorporate
the same or similar novel or unusual design feature, these 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 the Cessna Model 650 airplanes modified by Pro Star Aviation LLC. 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 the special conditions for these airplanes has
been subjected to the notice and comment procedure in several prior
instances and has been derived without substantive change from those
previously issued. Because a delay would significantly affect the
certification of the airplane, which is imminent, the FAA has
determined that prior public notice and comment are unnecessary and
impracticable, and good cause exists for adopting these special
conditions upon issuance. The FAA is requesting comments to allow
interested persons to submit views that may not have been
[[Page 24480]]
submitted in response to the prior opportunities for comment described
above.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
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
Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the supplemental type certification basis for the Cessna Aircraft
Company Model 650 Citation III airplanes modified by Pro Star Aviation
LLC.
1. Protection from Unwanted Effects of High-Intensity Radiated
Fields (HIRF). Each electronic and electrical 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 April 27, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-9306 Filed 5-9-05; 8:45 am]
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