[Federal Register: August 3, 2007 (Volume 72, Number 149)]
[Rules and Regulations]
[Page 43137-43139]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03au07-2]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. CE272; Special Conditions No. 23-212-SC]
Special Conditions: Centex Aerospace Inc., Cirrus Design
Corporation Model SR22; Installation of a Full Authority Digital Engine
Control (FADEC) Engine and the Protection of the System From the
Effects of 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 the Centex Aerospace
Inc. modified Cirrus Design Corporation Model SR22. This airplane as
modified by Centex Aerospace Inc. will have a novel or unusual design
feature(s) associated with the installation of a full authority digital
engine control (FADEC) engine. The applicable airworthiness regulations
do not contain adequate or appropriate safety standards for this design
feature. These special conditions contain the additional safety
standards that the Administrator considers necessary to establish a
level of safety equivalent to that established by the existing
airworthiness standards.
DATES: The effective date of these special conditions is July 26, 2007.
Comments must be received on or before September 4, 2007.
ADDRESSES: Comments may be mailed in duplicate to: Federal Aviation
Administration (FAA), Regional Counsel, ACE-7, Attention: Rules Docket,
Docket No. CE272, 901 Locust, Room 506, Kansas City, Missouri 64106, or
delivered in duplicate to the Regional Counsel at the above address.
Comments must be marked: Docket No. CE272. 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: Peter L. Rouse, Federal Aviation
Administration, Aircraft Certification Service, Small Airplane
Directorate, ACE-111, 901 Locust, Room 301, Kansas City, Missouri
64106; telephone: 816-329-4135, fax: 816-329-4090.
SUPPLEMENTARY INFORMATION: The FAA has determined that notice and
opportunity for prior public comment hereon are impracticable because
these procedures would significantly delay issuance of the design
approval 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.
Comments Invited
We invite interested people to take part in this rulemaking by
sending written comments, data, or views. The most helpful comments
reference a specific portion of the special conditions, explain the
reason for any recommended change, and include supporting data. We 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 can 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 by 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 us to let you know we received your comments on these
special conditions, send us 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 15, 2004, Centex Aerospace, Inc. applied for a
supplemental type certificate for the Cirrus Model SR22 to install a
full authority digital engine control in the Cirrus Model SR22. CenTex
Aerospace, Inc. plans to install a Teledyne Continental Motors model
IOF-550-N engine in the Cirrus Design Corporation Model SR-22 airplane.
This type certified engine, approved under FAA Type Certificate E3SO;
Revision 7, dated
[[Page 43138]]
February 4, 2002, incorporates Full Authority Digital Electronic
Controls (FADEC) fuel and ignition control system. Even though the
engine control system is certificated as part of the engine and does
not interface or share data with any of the airplane systems, the
installation of an engine with an electronic control system requires
evaluation due to critical environmental effects and possible effects
on or by other airplane systems. For example, indirect effects of
lightning, radio interference with other airplane electronic systems,
shared engine and airplane data and power sources.
The Cirrus Model SR22 is currently approved under Type Certificate
No. A00009CH. The Cirrus Model SR22 is a 3,400 pound single-engine,
four-place, fixed-gear airplane powered by a 310 hp reciprocating
engine. It has a conventional tractor configuration and uses composites
for the structure. Some unique features of the SR-22 include sidestick
controls and a ballistic recovery system, and a single combination
throttle/propeller control lever.
Type Certification Basis
Under the provisions of Sec. 21.101, Centex Aerospace, Inc. must
show that the Cirrus Model SR22, as changed, continues to meet the
applicable provisions of the regulations incorporated by reference in
Type Certificate No. A00009CH, 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 regulations incorporated by
reference in Type Certificate No. A00009CH are as follows:
Model SR22: Part 23 of the Federal Aviation Regulations effective
February 1, 1965, as amended by 23-1 through 23-53, except as follows:
23.301 through Amendment 47
23.855, 23.1326, 23.1359, not applicable
Federal Aviation Regulation 36, dated December 1, 1969, as amended
by current amendment as of the date of type Certification.
Equivalent Safety Items:
Equivalent Levels of Safety finding (ACE-96-5) made per the
provisions of 14 CFR part 23, Sec. 23.221; Refer to FAA ELOS letter
dated June 10, 1998 for models SR20, SR22.
Equivalent Levels of Safety finding (ACE-00-09) made per the
provisions of 14 CFR part 23, Sec. Sec. 23.1143(g) and 23.1147(b);
Refer to FAA ELOS letter dated September 11, 2000 for model SR22.
Special Conditions:
23-ACE-88 for ballistic parachute.
23-134-SC for protection of systems for High Intensity Radiated
Fields (HIRF).
23-163-SC for inflatable restraint system.
In addition, if the regulations incorporated by reference do not
provide adequate standards regarding the change, the applicant must
comply with certain regulations in effect on the date of application
for the change.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 23, Sec. 23.1309) do not contain
adequate or appropriate safety standards for the Model SR22 because of
a novel or unusual design feature, special conditions are prescribed
under the provisions of Sec. 21.16.
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
Sec. 21.101.
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 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.
Novel or Unusual Design Features
The Centex Aerospace Inc. modified Cirrus Model SR22 will
incorporate the following novel or unusual design features:
An engine that includes an electronic control system with Full
Authority Digital Engine control (FADEC) capability.
Many advanced electronic systems are prone to either upsets or
damage, or both, at energy levels lower than analog systems. The
increasing use of high power radio frequency emitters mandates
requirements for improved high intensity radiated fields (HIRF)
protection for electrical and electronic equipment. Since the
electronic engine control system used on the Centex Aerospace, Inc.
modified Cirrus Design Corporation Model SR22 will perform critical
functions, provisions for protection from the effects of HIRF should be
considered and, if necessary, incorporated into the airplane design
data. The FAA policy contained in Notice 8110.71, dated April 2, 1998,
establishes the HIRF energy levels that airplanes will be exposed to in
service. The guidelines set forth in this notice are the result of an
Aircraft Certification Service review of existing policy on HIRF, in
light of the ongoing work of the Aviation Rulemaking Advisory Committee
(ARAC) Electromagnetic Effects Harmonization Working Group (EEHWG). The
EEHWG adopted a set of HIRF environment levels in November 1997 that
were agreed upon by the FAA, the Joint Aviation Authorities (JAA), and
industry participants. As a result, the HIRF environments in this
notice reflect the environment levels recommended by this working
group. This notice states that a FADEC is an example of a system that
should address the HIRF environments.
Even though the control system will be certificated as part of the
engine, the installation of an engine with an electronic control system
requires evaluation due to the possible effects on or by other airplane
systems (e.g., radio interference with other airplane electronic
systems, shared engine and airplane power sources). The regulatory
requirements in 14 CFR part 23 for evaluating the installation of
complex systems, including electronic systems, are contained in Sec.
23.1309. However, when Sec. 23.1309 was developed, the use of
electronic control systems for engines was not envisioned; therefore,
the Sec. 23.1309 requirements were not applicable to systems
certificated as part of the engine (reference Sec. 23.1309(f)(1)).
Also, electronic control systems often require inputs from airplane
data and power sources and outputs to other airplane systems (e.g.,
automated cockpit powerplant controls such as mixture setting).
Although the parts of the system that are not certificated with the
engine could be evaluated using the criteria of Sec. 23.1309, the
integral nature of systems such as these makes it unfeasible to
evaluate the airplane portion of the system without including the
engine portion of the system. However, Sec. 23.1309(f)(1) again
prevents complete evaluation of the installed airplane system since
evaluation of the engine system's effects is not required.
Therefore, special conditions are issued for the Centex Aerospace,
Inc. modified Cirrus Design Corporation Model SR22 to provide HIRF
protection.
Applicability
As discussed above, these special conditions are applicable to the
Centex Aerospace, Inc. modified Cirrus Design Corporation Model SR22.
Should Centex Aerospace, Inc. apply at a later date for a supplemental
type certificate to modify any other model included on Type Certificate
No. A00009CH, to incorporate the same novel or unusual
[[Page 43139]]
design feature, the special conditions would apply to that model as
well.
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. Therefore, because a delay would
significantly affect the certification of the airplane, which is
imminent, the FAA has determined that prior public notice and comment
are unnecessary and impracticable, and good cause exists for adopting
these special conditions upon 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
0
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 Centex Aerospace, Inc. modified
Cirrus Design Corporation Model SR22.
1. High Intensity Radiated Fields (HIRF) Protection. In showing
compliance with 14 CFR part 21 and the airworthiness requirements of 14
CFR part 23, protection against hazards caused by exposure to HIRF
fields for the full authority digital engine control system, which
performs critical functions, must be considered. To prevent this
occurrence, the electronic engine control system must be designed and
installed to ensure that the operation and operational capabilities of
this critical system are not adversely affected when the airplane is
exposed to high energy radio fields.
At this time, the FAA and other airworthiness authorities are
unable to precisely define or control the HIRF energy level to which
the airplane will be exposed in service; therefore, the FAA hereby
defines two acceptable interim methods for complying with the
requirement for protection of systems that perform critical functions.
(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 external HIRF threat environment defined
in the following table:
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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-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 peak
electrical strength, without the benefit of airplane structural
shielding, in the frequency range of 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. Data used for engine
certification may be used, when appropriate, for airplane
certification.
Issued in Kansas City, Missouri on July 26, 2007.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-14935 Filed 8-2-07; 8:45 am]
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