[Federal Register Volume 66, Number 188 (Thursday, September 27, 2001)]
[Rules and Regulations]
[Pages 49271-49273]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-24219]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM196; Special Conditions No. 25-185-SC]


Special Conditions: Dassault Aviation Mystere-Falcon 50; 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 Dassault Aviation 
Mystere-Falcon 50 airplanes modified by ElectroSonics. 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 dual Electronic Primary Flight Display systems that 
perform critical 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 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 7, 
2001. Comments must be received on or before October 29, 2001.

ADDRESSES: Comments on these special conditions may be mailed in 
duplicate to: Federal Aviation Administration, Transport Airplane 
Directorate, Attention: Rules Docket (ANM-113), Docket No. NM196, 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. NM196. 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: Meghan Gordon, FAA, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-2138; 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 certification of the 
airplane 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

[[Page 49272]]

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 
rules docket number and be submitted in duplicate to the address 
specified above. The Administrator will consider all communications 
received on or before the closing date for comments. 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. 
Persons wishing the FAA to acknowledge receipt of their comments 
submitted in response to these special conditions must include with 
those comments a self-addressed, stamped postcard on which the 
following statement is made: ``Comments to Docket No. NM196.'' The 
postcard will be date stamped and returned to the commenter.

Background

    On July 3, 2001, ElectroSonics, 4391 International Gateway, 
Columbus, Ohio, applied for a Supplemental Type Certificate (STC) to 
modify Dassault Aviation Mystere-Falcon 50 airplanes. The Dassault 
Aviation Mystere-Falcon 50 is a small transport category airplane. The 
Dassault Aviation Mystere-Falcon 50 airplanes are powered by three 
AlliedSignal Model TFE 731-3-1C Turbofan Engines with a maximum takeoff 
weight of 38,800 pounds. This aircraft operates with a 2-pilot crew and 
can hold up to 19 passengers. The modification incorporates the 
installation of a Rockwell Collins FDS-2000 Flight Display System. The 
FDS-2000 is a replacement for the existing Analog Flight 
Instrumentation, while also providing additional functional capability 
and redundancy in the system. The avionics/electronics and electrical 
systems installed in this airplane have the potential to be vulnerable 
to high-intensity radiated fields (HIRF) external to the airplane.

Type Certification Basis

    Under the provisions of 14 CFR 21.101, ElectroSonics must show that 
the Dassault Aviation Mystere-Falcon 50 airplanes, as changed, continue 
to meet the applicable provisions of the regulations incorporated by 
reference in Type Certificate No. A46EU, 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 Dassault Aviation Mystere-
Falcon 50 airplanes include 14 CFR part 25, dated February 1, 1965, as 
amended by amendment 25-1 through amendment 25-34; Sec. 25.255, as 
amended by amendment 25-42; Secs. 25.979(d) and (e), as amended by 
amendment 25-38; 25.1013(b)(1) as amended by amendment 25-36; 
Sec. 25.1351(d), as amended by amendment 25-41; 25.1353(c)(6), as 
amended by amendment 25-42; Special Conditions No. 25-86-EU-24 dated 
March 6, 1979.
    If the Administrator finds that the applicable airworthiness 
regulations (that is, part 25, as amended) do not contain adequate or 
appropriate safety standards for the Dassault Aviation Mystere-Falcon 
50 airplanes modified by ElectroSonics 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, these Dassault Aviation Mystere-Falcon 50 airplanes must 
comply with the fuel vent and exhaust emission requirements of 14 CFR 
part 34, and the noise certification requirements of part 36.
    Special conditions, as defined in Sec. 11.19, are issued in 
accordance with 11.38 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 ElectroSonics 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 also apply to the other model 
under the provisions of Sec. 21.101(a)(1).

Novel or Unusual Design Features

    As noted earlier, the Dassault Aviation Mystere-Falcon 50 airplanes 
modified by ElectroSonics will incorporate dual Electronic Primary 
Flight Display systems that will perform critical functions. These 
systems may be vulnerable to high-intensity radiated fields 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, this 
system is considered to be a novel or unusual design feature.

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 Dassault Aviation Mystere-Falcon 50 
airplanes modified by ElectroSonics. These 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 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.

[[Page 49273]]



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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 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 
Dassault Aviation Mystere-Falcon 50 airplanes modified by 
ElectroSonics. Should ElectroSonics 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).

Conclusion

    This action affects only certain design features on the Dassault 
Aviation Mystere-Falcon 50 airplanes modified by ElectroSonics. 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. 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 the Dassault Aviation 
Mystere-Falcon 50 airplanes modified by ElectroSonics.
    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 September 7, 2001.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-24219 Filed 9-26-01; 8:45 am]
BILLING CODE 4910-13-P