[Federal Register Volume 67, Number 14 (Tuesday, January 22, 2002)]
[Proposed Rules]
[Pages 2827-2828]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-1506]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 67, No. 14 / Tuesday, January 22, 2002 / 
Proposed Rules  

[[Page 2827]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM207; Special Conditions No. 25-02-02-SC


Special Conditions: Fairchild Dornier GmbH, Model 728-100; High 
Intensity Radiated Fields (HIRF)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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

SUMMARY: This notice proposes special conditions for the Fairchild 
Dornier GmbH Model 728-100 airplane. This airplane will have novel or 
unusual design features when compared to the state of technology 
envisioned in the airworthiness standards for transport category 
airplanes. The airplane design will include an electronic flight 
control system as well as advanced avionics for the display and control 
of critical airplane functions. 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, in part, 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. Additional special conditions may 
also be defined.

DATES: Comments must be received on or before March 8, 2002.

ADDRESSES: Comments on this proposal may be mailed in duplicate to: 
Federal Aviation Administration, Transport Airplane Directorate, 
Attention: Rules Docket (ANM-113), Docket No. NM207, 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. NM207. 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: Tom Groves, FAA, International Branch, 
ANM-116, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-1503; facsimile (425) 227-1149.

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 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

    The FAA invites interested persons to participate in this 
rulemaking by submitting written comments, data, or views. The most 
helpful comments reference a specific portion of the proposal, 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 proposed 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 notice between 7:30 a.m. and 4:00 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 the 
proposal for special conditions in light of the comments we receive.
    If you want the FAA to acknowledge receipt of your comments on this 
proposal, 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 May 5, 1998, Fairchild Dornier GmbH, applied for a type 
certificate for their new Model 728-100 airplane. The Model 728-100 is 
a 70-85 passenger twin-engine regional jet with a maximum takeoff 
weight of 77,600 pounds.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Fairchild Dornier GmbH must 
show that the Model 728-100 airplane meets the applicable provisions of 
part 25, as amended by Amendments 25-1 through 25-96. Fairchild Dornier 
GmbH has also applied to extend the certification basis to include 
Amendments 25-97, 25-98, and 25-104.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the Model 728-100 airplane 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 728-100 airplane 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 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. 21.17(a)(2).
    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(a)(1).

Novel or Unusual Design Features

    As noted earlier, the Fairchild Dornier GmbH Model 728-100 will 
include an electronic flight control system as well as advanced 
avionics for the display and control of critical airplane functions.

[[Page 2828]]

These systems may be vulnerable to HIRF 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, these systems are considered 
to be novel or unusual design features.

Discussion

    There is no specific regulation that addresses protection 
requirements for electrical and electronic 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 that is equivalent to 
that intended by the regulations incorporated by reference, special 
conditions are needed for the Fairchild Dornier GmbH Model 728-100. 
These proposed 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, plus the advent of space and satellite communications 
coupled with electronic command and control of the airplane, the 
immunity of critical 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 with the HIRF protection special 
condition is shown in accordance with either 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 
indicated in Table 1 for the frequency ranges indicated. Both peak and 
average field strength components from Table 1 are to be demonstrated.

                                 Table 1
------------------------------------------------------------------------
                                                         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-30MHz..........................................     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 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 
Fairchild Dornier GmbH Model 728-100. Should Fairchild Dornier apply at 
a later date for a change to the type certificate to include another 
model incorporating the same novel or unusual design feature, these 
special conditions would apply to that model as well under the 
provisions of Sec. 21.101(a)(1). Fairchild Dornier has submitted 
applications for certification of both increased and reduced passenger 
capacity derivatives of the 728-100. These derivative models are 
designated the 928-100, and the 528-100, respectively. As currently 
proposed, these derivative models share the same design features of an 
electronic flight control system as well as advanced avionics for the 
display and control of critical airplane functions as the 728-100, and 
it is anticipated that they will be be included in the applicability of 
this proposed special condition.

Conclusion

    This action affects only certain novel or unusual design features 
on the Fairchild Dornier GmbH Model 728-100 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.

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 Proposed Special Conditions

    Accordingly, the Federal Aviation Administration (FAA) proposes the 
following special conditions as part of the type certification basis 
for Fairchild Dornier GmbH Model 728-100 airplanes.
    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 January 9, 2002.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-1506 Filed 1-18-02; 8:45 am]
BILLING CODE 4910-13-P