[Federal Register Volume 64, Number 155 (Thursday, August 12, 1999)]
[Proposed Rules]
[Pages 43946-43948]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-20859]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR part 25

[Docket No. NM160, Notice No. 25-99-07-SC]


Special Conditions: Dassault Aviation Falcon Model 20-C5/-D5/-E5/
-F5 Airplanes; High Intensity Radiated Fields (HIRF)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This notice proposes special conditions for the Dassault 
Aviation Falcon Model 20-C5/-D5/-E5/-F5 airplanes as modified by 
Garrett Aviation Services. The Model 20-C5/-D5/-E5/-F5 airplanes are 
equipped with a high-technology digital avionics system that performs 
critical functions. The applicable type certification 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 provide the additional safety 
standards that the Administrator considers necessary to ensure that the 
critical functions that this system performs are maintained when the 
airplane is exposed to HIRF.

DATES: Comments must be received on or before September 13, 1999.

ADDRESSES: Comments on this proposal may be mailed in duplicate to: 
Federal Aviation Administration, Transport Airplane Directorate, 
Attention: Rules Docket (ANM-114), Docket No. NM160, 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. NM160. 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: Connie Beane, FAA, Transport Airplane 
Directorate, Aircraft Certification Service, Standardization Branch, 
ANM-113, 1601 Lind Avenue SW., Renton, Washington, 98055-4056; 
telephone (425) 227-2796; facsimile (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of 
these proposed special conditions by submitting such written data, 
views, or arguments, as they may desire. Communications should identify 
the regulatory docket or notice 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 proposals described in this notice 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. Persons wishing the FAA to acknowledge receipt of their 
comments submitted in response to this notice must include with those 
comments a self-addressed, stamped postcard on which the following 
statement is made: ``Comments to Docket No. NM160.'' The postcard will 
be date stamped and returned to the commenter.

Background

    On November 8, 1998, Garrett Aviation Services applied for a 
supplemental type certificate (STC) to modify Dassault Aviation Falcon 
Model 20-C5/-D5/-E5/-F5 airplanes listed on Type Certificate A7EU.
    The Model 20-C5/-D5/-E5/-F5 series of low wing airplanes are 
pressurized

[[Page 43947]]

airplanes with twin, Garrett TRE731-5AR turbofans that are configured 
for 8-10 passengers and a crew of 2. The airplane has a maximum takeoff 
weight of 29,000 pounds, a maximum landing weight of 27,734 pounds, and 
a range of 1600 nautical miles. The overall length of the Falcon Model 
20-C5/-D5/-E5/-F5 airplanes is 56 feet 3 inches, and the wing span is 
53 feet, 6 inches.
    The modification incorporates the installation of flat panel 
displays for display of critical flight parameters (altitude, airspeed, 
and attitude) to the crew. These displays can be susceptible to 
disruption to both command/response signals as a result of electrical 
and magnetic interference. This disruption of signals could result in 
loss of all critical flight displays and annunciations or present 
misleading information to the pilot.

Type Certification Basis

    Under the provisions of 14 CFR 21.101, Garrett Aviation Services 
must show that the Dassault Aviation Falcon Model 20-C5/-D5/-E5/-F5 
airplanes, as changed, continue to meet the applicable provisions of 
the regulations incorporated by reference in Type Certificate No. A7EU, 
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. A7EU are as follows:
    The certification basis for the modified Dassault Aviation Falcon 
Model 20-C5/-D5/-E5/-F5 airplanes include CAR 4b effective December 
1953, through Amendment 4b-12 and SR422B, as amended by type 
certificate data sheet.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., CAR 4b, as amended) do not contain adequate or 
appropriate safety standards for the Dassault Aviation Falcon Model 20-
C5/-D5/-E5/-F5 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 20-C5/-D5/-E5/-F5 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 appropriate, are issued in accordance with 
14 CFR 11.49, as required by Secs. 11.28 and 11.29(b), and become part 
of the 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 Garrett Aviation Services 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 
under the provisions of Sec. 21.101(a)(1).

Novel or Unusual Design Features

    The modified Dassault Aviation Falcon Model 20-C5/-D5/-E5/-F5 
airplanes will incorporate the following new design feature: a new 
electronic flat panel display system, which was not available at the 
time of certification of these airplanes, that performs critical 
functions. This system may be vulnerable to HIRF external to the 
airplane.

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 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 equivalent to that 
intended by the regulations incorporated by reference, special 
conditions are needed for the Dassault Aviation Falcon Model 20-C5/-D5/
-E5/-F5 airplanes, which require that new electrical and electronic 
systems, such as the flat panel displays for display of critical flight 
parameters (altitude, airspeed, and attitude) to the crew, 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 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 per meter peak 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.

------------------------------------------------------------------------
                                                            Frequency
           Field Strength (volts per meter)            -----------------
                                                          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.
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    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. In general, these standards are 
less critical than the threat level that was previously used as the 
basis for some earlier special conditions.

Applicability

    As discussed above, these special conditions are applicable to 
Dassault Aviation Falcon Model 20-C5/-D5/-E5/-F5 airplanes modified by 
Garrett Aviation Services. Should Garrett Aviation Services apply at a 
later date 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, these special conditions would apply 
to that model as well under the provisions of Sec. 21.101(a)(1).

[[Page 43948]]

Conclusion

    This action affects only certain novel or unusual design features 
on Dassault Aviation Falcon Model 20-C5/-D5/-E5/-F5 airplanes modified 
by Garrett Aviation Services. 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.

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 Dassault Aviation Falcon Model 20-C5/-D5/-E5/-F5 airplanes modified 
by Garrett Aviation Services.
    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.
    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 July 29, 1999.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service, ANM-100.
[FR Doc. 99-20859 Filed 8-11-99; 8:45 am]
BILLING CODE 4910-13-P