[Federal Register Volume 69, Number 113 (Monday, June 14, 2004)]
[Rules and Regulations]
[Pages 32851-32853]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-13308]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM279; Special Conditions No. 25-263-SC]


Special Conditions: Gulfstream Aerospace LP Model Gulfstream 200 
(Galaxy) 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 Gulfstream Aerospace 
LP Model Gulfstream 200 (Galaxy) airplanes modified by Gulfstream 
Aerospace Corporation of Dallas, Texas. 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 electronic laser inertial reference system that performs 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 June 3, 2004. 
Comments must be received on or before July 14, 2004.

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. NM279, 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. NM279.

FOR FURTHER INFORMATION CONTACT: Connie Beane, FAA, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-2796; facsimile (425) 227-1232.

SUPPLEMENTARY INFORMATION:

[[Page 32852]]

Comments Invited

    The FAA has determined that 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. However, 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 special conditions, 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 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 the address in the ADDRESSES section of 
this preamble between 7:30 a.m., and 4 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 
these special conditions based on the comments we receive.
    If you want the FAA to acknowledge receipt of your comments on 
these special conditions, include with your comments a pre-addressed, 
stamped postcard on which the docket number appears. We will stamp the 
postcard and mail it back to you.

Background

    On March 23, 2004, Gulfstream Aerospace Corporation of Dallas, 
Texas, applied for a Supplemental Type Certificate (STC) to modify 
Model Gulfstream 200 (Galaxy) airplanes. These airplanes are low-wing, 
pressurized transport category airplanes with two fuselage-mounted jet 
engines. They are capable of seating up to 19 passengers, depending 
upon the configuration. The modification incorporates the installation 
of a new electronic laser inertial reference system, which interfaces 
with the Automatic Flight Control System (AFCS), Flight Management 
System (FMS), and Electronic Flight Instrumentation (EFIS), providing 
attitude, heading and position data. This system has a potential to be 
vulnerable to high-intensity radiated fields (HIRF) external to the 
airplane.

Type Certification Basis

    Under the provisions of Title 14, Code of Federal Regulations (CFR) 
21.101, Gulfstream Aerospace Corporation must show that the Model 
Gulfstream 200 (Galaxy) airplanes, as changed, continue to meet the 
applicable provisions of the regulations incorporated by reference in 
Type Certificate No. A53NM, 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. 
A53NM include 14 CFR part 25, as amended by Amendments 25-1 through 25-
82.
    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 modified Model Gulfstream 200 
(Galaxy) 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 Gulfstream 200 (Galaxy) airplanes 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 defined in 14 CFR 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 Gulfstream Aerospace Corporation 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.

Novel or Unusual Design Features

    The modified Model Gulfstream 200 (Galaxy) airplanes will 
incorporate a new electronic laser inertial reference system that will 
perform critical functions. This system may be vulnerable to high-
intensity radiated fields external to the airplane.

Discussion

    There is no specific regulation that addresses 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 equivalent to that 
intended by the regulations incorporated by reference, special 
conditions are needed for Model Gulfstream 200 (Galaxy) airplanes. 
These special conditions require that installation of a new electronic 
laser inertial reference system that 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 (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 is 
identified in the following table for the frequency ranges indicated. 
Both peak and average field strength components from the Table are to 
be demonstrated.

[[Page 32853]]



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                                                 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 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 
Model Gulfstream 200 (Galaxy) airplanes. Should Gulfstream Aerospace 
Corporation 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.

Conclusion

    This action affects only certain novel or unusual design features 
on the Model Gulfstream 200 (Galaxy) airplanes modified by Gulfstream 
Aerospace Corporation. 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 for these airplanes has 
been subjected to the notice and comment procedure in several prior 
instances and has been derived without substantive change from those 
previously issued. 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 immediately. 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.


0
The authority citation for these special conditions is as follows:

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

The Special Conditions

0
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 Model Gulfstream 200 
(Galaxy) airplanes modified by Gulfstream Aerospace Corporation.
    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 June 3, 2004.
Franklin Tiangsing,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-13308 Filed 6-10-04; 8:45 am]
BILLING CODE 4910-13-P