[Federal Register Volume 65, Number 205 (Monday, October 23, 2000)]
[Rules and Regulations]
[Pages 63196-63198]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-27181]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM177; Special Conditions No. 25-163-SC]


Special Conditions: Canadair Model CL-600-2B19 Series 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 Canadair Model CL-600-
2B19 series airplanes modified by Rockwell Collins Flight Dynamics. 
These modified airplanes will have a novel or unusual design feature 
when compared to the state of technology envisioned in the 
airworthiness standards for transport category airplanes. The 
modification incorporates the installation of a new Head-Up Guidance 
System (HGS). The HGS will utilize electrical and electronic systems 
that perform critical functions. The applicable airworthiness 
regulations do not contain adequate or appropriate safety standards for 
the protection of this system 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 October 17, 
2000. Comments must be received on or before November 22, 2000.

ADDRESSES: Comments on these special conditions may be mailed in 
duplicate to: Federal Aviation Administration, Transport Airplane 
Directorate, Attention: Rules Docket (ANM-114), Docket No. NM177, 1601 
Lind Avenue SW., Renton, Washington 98055-4056; or delivered in 
duplicate to the Transport Airplane Directorate at the above address. 
All comments must be marked: Docket No. NM177. Comments may be 
inspected in the Rules Docket weekdays, except Federal holidays, 
between 7:30 a.m. and 4:00 p.m.

FOR FURTHER INFORMATION CONTACT: Gerald Lakin, FAA, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-1187; facsimile (425) 227-1149.

SUPPLEMENTARY INFORMATION:   

Comments Invited

    The FAA has determined that good cause exists for making these 
special conditions effective upon issuance; however, interested persons 
are invited to submit such written data, views, or arguments, as they 
may desire. Communications should identify the regulatory docket 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. These 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 these special conditions must include a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. NM177.'' The postcard will be date stamped and returned 
to the commenter.

Background

    On June 26, 2000, Rockwell Collins Flight Dynamics, 16600 S.W. 72nd 
Avenue, Portland, OR 97224, applied for a Supplemental Type Certificate 
(STC) for Canadair Model CL-600-2B19 series airplanes. The Model CL-
600-2B19 is a Model Regional Jet Series 100 passsenger airplane with 
two AVCO Lycoming ALF-502L or ALF-502L-2 engines. These airplanes will 
incorporate a Head-Up Guidance System (HGS), manufactured by Rockwell 
Collins Flight Dynamics, which displays attitude and heading 
information.

[[Page 63197]]

    The HGS performs critical functions associated with the display of 
attitude and heading information to the pilot. These functions can be 
susceptible to disruption of both command and response signals as a 
result of electrical and magnetic interference caused by high-intensity 
radiated fields (HIRF) external to the airplane. This disruption of 
signals could result in loss of critical flight displays and 
annunciations, or could present misleading information to the pilot.

Type Certification Basis

    Under the provisions of 14 CFR 21.101, Rockwell Collins Flight 
Dynamics must show that the Model CL-600-2B19 series airplanes, as 
changed, continue to meet the applicable provisions of the regulations 
incorporated by reference in Type Certificate No. A21EA, 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 included in the certification 
basis for the Model CL-600-2B19 series airplanes include Title 14, Code 
of Federal Regulations (14 CFR) part 25, as amended by Amendments 25-1 
through 25-62, plus additional requirements listed in the type 
certificate data sheet 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 the Model CL-600-2B19 series 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 Model CL-600-2B19 series airplanes must comply with the 
fuel vent and exhaust emission requirements of part 34 and the noise 
certification requirements of part 36.
    Special conditions, as appropriate, are issued in accordance with 
Sec. 11.49, as required by Secs. 11.28 and 11.29, and become part of 
the airplane's 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 included on the same type 
certificate to incorporate the same novel or unusual design features, 
these special conditions would also apply to the other model under the 
provisions of Sec. 21.101(a)(1).

Novel or Unusual Design Features

    As stated earlier, the Model CL-600-2B19 series airplanes modified 
by Rockwell Collins Flight Dynamics will incorporate a HGS system, 
which performs critical functions. The HGS system contains electronic 
equipment for which 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. This system may be 
vulnerable to HIRF external to the airplane. Accordingly, this system 
is considered to be a novel or unusual design feature.

Discussion

    There is no specific regulation that addresses the requirements for 
protection of electrical and electronic systems from HIRF. Increased 
power levels from ground-based radio transmitters and the growing use 
of sensitive electrical and electronic systems to command and control 
airplanes have made it necessary to provide adequate protection.
    To ensure that a level of safety is achieved that is equivalent to 
that intended by the regulations incorporated by reference, special 
conditions are needed for the Model CL-600-2B19 airplanes modified to 
include the Rockwell Collins Flight Dynamics HGS system. These special 
conditions will require that this system, which performs 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, plus the advent of space and satellite communications 
coupled with electronic command and control of the airplane, the 
immunity of critical digital avionics 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 with the HIRF protection special 
condition is shown with either paragraph 1 or 2 below:
    1. A minimum threat of 100 volts rms 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 following field 
strengths 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-8 GHz.............................            1000             200
8 GHz-12 GHz............................            3000             300

[[Page 63198]]

 
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 
Canadair Model CL-600-2B19 series airplanes modified by Rockwell 
Collins Flight Dynamics to include the Rockwell Collins Flight Dynamics 
HGS system. Should Rockwell Collins Flight Dynamics apply at a later 
date for a supplemental type certificate to modify any other model 
included on Type Certificate A21EA to incorporate the same novel or 
unusual design features, these special conditions would apply to that 
model as well under the provisions of Sec. 21.101(a)(1).

Conclusion

    This action affects only certain novel or unusual design features 
on Canadair Model CL-600-2B19 series airplanes modified by Rockwell 
Collins Flight Dynamics. 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 airplanes.
    The substance of the 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 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 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Special Conditions

    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 Canadair Model CL-600-
2B19 series airplanes modified by Rockwell Collins Flight Dynamics.
    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 the 
continued safe flight and landing of the airplane.

    Issued in Renton, Washington, on October 17, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-27181 Filed 10-20-00; 8:45 am]
BILLING CODE 4910-13-U