[Federal Register Volume 67, Number 188 (Friday, September 27, 2002)]
[Rules and Regulations]
[Pages 60855-60857]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-24667]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 23

[Docket No. CE190; Special Conditions No. 23-130-SC]


Special Conditions: CenTex Aerospace, Inc.; Beech Model A36 
airplane, Installation of Full Authority Digital Engine Control (FADEC) 
System 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.

-----------------------------------------------------------------------

SUMMARY: These special conditions are issued to CenTex Aerospace, Inc.; 
7805 Karl May Drive; Waco, Texas 76708 for the Beech Model A36 
airplane. This airplane will have a novel or unusual design feature(s) 
associated with the installation of an engine that uses an electronic 
engine control system in place of the engine's mechanical system. 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 September 18, 
2002. Comments must be received on or before October 28, 2002.

ADDRESSES: Comments may be mailed in duplicate to: Federal Aviation 
Administration, Regional Counsel, ACE-7, Attention: Rules Docket Clerk, 
Docket No. CE190, Room 506, 901 Locust, Kansas City, Missouri 64106. 
All comments must be marked: Docket No. CE190. 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, Federal Aviation 
Administration, Aircraft Certification Service, Small Airplane 
Directorate, ACE-111, 901 Locust, Room 301, Kansas City, Missouri 
64106; 816-329-4127 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 approval 
design and thus delivery of the affected aircraft. In

[[Page 60856]]

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

    Interested persons are invited to submit such written data, views, 
or arguments as they may desire. Communications should identify the 
regulatory docket or special condition 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 CE190.'' The postcard will be date stamped and returned 
to the commenter.

Background

    On February 11, 2002, CenTex Aerospace, Inc. applied for a 
supplemental type certificate for their Beech Model A36 airplane. The 
Beech Model A36 is powered by a Teledyne Continental Motors model IOF-
550-B engine. This engine incorporates Full Authority Digital 
Electronic Controls.

Type Certification Basis

    Under the provisions of 14 CFR Sec.  21.101, CenTex Aerospace, Inc. 
must show that the Beech Model A36 meets the applicable provisions of 
14 CFR part 23, as amended by Amendments 23-1 through 23-53 thereto.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 23) do not contain adequate or 
appropriate safety standards for the Beech Model A36 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 Beech Model A36 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, and the FAA must issue a 
finding of regulatory adequacy pursuant to section 611 of Public Law 
92-574, the ``Noise Control Act of 1972.''
    Special conditions, as appropriate, as defined in Sec.  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 the type certificate for that model be amended 
later to include any other model that incorporates 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

    The Beech Model A36 will incorporate the following novel or unusual 
design features:
    The CenTex Aerospace, Inc. Beech Model A36 airplane will use an 
engine that includes an electronic control system with full engine 
authority 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. 
Beech Model A36 will perform critical functions, provisions for 
protection from the effects of HIRF fields 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 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, 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 full authority digital engine control 
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 proposed for the CenTex 
Aerospace, Inc., Beech Model A36 to provide HIRF protection and to 
evaluate the installation of the electronic engine control system for 
compliance with the requirements of Sec.  23.1309(a) through (e) at 
Amendment 23-46.

Applicability

    As discussed above, these special conditions are applicable to the 
Beech Model A36. Should CenTex Aerospace, Inc. apply at a later date 
for a change to the type certificate to include another model 
incorporating 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 Beech model A36 airplane. It is not a rule of general 
applicability, and it 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

[[Page 60857]]

contained herein. For this reason, and 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

    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., Beech 
Model A36 airplane.
    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:

------------------------------------------------------------------------
                                                        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 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.

    2. Electronic Engine Control System. The installation of the 
electronic engine control system must comply with the requirements of 
Sec.  23.1309(a) through (e) at Amendment 23-46. The intent of this 
requirement is not to re-evaluate the inherent hardware reliability of 
the control itself, but rather determine the effects, including 
environmental effects addressed in Sec.  23.1309(e), on the airplane 
systems and engine control system when installing the control on the 
airplane. When appropriate, engine certification data may be used when 
showing compliance with this requirement.

    Issued in Kansas City, Missouri on September 18, 2002.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 02-24667 Filed 9-26-02; 8:45 am]
BILLING CODE 4910-13-P