[Federal Register Volume 66, Number 222 (Friday, November 16, 2001)]
[Rules and Regulations]
[Pages 57648-57650]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-28676]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM202; Special Conditions No. 25-191-SC]


Special Conditions: Gulfstream G-1159, G-1159A, G-1159B Series 
Airplanes; High-Intensity Radiated Fields (HIRF)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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

SUMMARY: These special conditions are issued for Gulfstream G-1159, G-
1159A, G-1159B series airplanes modified by Garrett Aviation Services. 
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 Honeywell Epic Control 
Display System for Retrofit (CDS-R). The system consists of dual 
Electronic Primary Flight Display Systems, which replace the existing 
Primary Flight Display System. The Electronic Primary Flight Display 
Systems 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 
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 November 6, 
2001.
    Comments must be received on or before December 17, 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. NM202, 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. NM202. 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, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-2976; facsimile (425) 227-1320.

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. The FAA therefore 
finds that good cause exists for making these 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. NM202.'' The 
postcard will be date stamped and returned to the commenter.

Background

    On January 9, 2001, Garrett Aviation Services, 1200 North Airport 
Drive, Capital Airport, Springfield, Illinois 62707, applied for a 
Supplemental Type Certificate (STC) for the Gulfstream G-1159, G-1159A, 
G-1159B series airplanes. The Gulfstream G-1159, G-1159A, G-1159B 
series airplanes are small transport category airplanes powered by two 
turbofan engines with a maximum takeoff weight of 69,700 pounds. The 
aircraft operate with a two pilot crew and can carry up to 19 
passengers. The modified airplanes incorporate the installation of a 
Honeywell Epic Control Display System for Retrofit (CDS-R). The system 
consists of dual Electronic Primary Flight Display systems that replace 
the existing Primary Flight Display systems. The Honeywell Epic DCS-R 
has 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, Garrett Aviation Services 
must show that the Gulfstream G-1159, G-1159A, G-1159B series 
airplanes, as changed, continue to meet the applicable provisions of 
the regulations incorporated by reference in Type Certificate No. 
A12EA, 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 Gulfstream G-1159, G-1159A, G-1159B series airplanes 
include 14 CFR part 25, as amended by Amendment 25-1 through Amendment 
25-41 except for special conditions and exceptions noted in Type 
Certificate Data Sheet (TCDS) A12EA.
    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 Gulfstream G-1159, G-1159A, G-
1159B 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 Gulfstream G-1159, G-1159A, G-1159B series airplanes 
must comply with the fuel vent and exhaust emission requirement of 14 
CFR part 34 and the noise certification requirement of 14 CFR part 36.
    Special conditions, as defined in Sec. 11.19, are issued in 
accordance with Sec. 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 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).

[[Page 57649]]

Novel or Unusual Design Features

    The Gulfstream G-1159, G-1159A, G-1159B series airplanes will 
incorporate dual Electronic Primary Flight Display Systems that will 
perform critical functions. The existing airworthiness standards (14 
CFR part 25) do not contain adequate or appropriate safety standards 
that address protecting this equipment from the adverse effects of 
HIRF. These instruments may be vulnerable to HIRF external to the 
airplane. Accordingly, these instruments are 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 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 Gulfstream G-1159, G-1159A, G-1159B 
series airplanes modified to incorporate dual Electronic Primary Flight 
Display Systems. These special conditions will require that these 
instruments, which 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 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.

------------------------------------------------------------------------
                                                         Field strength
                                                           (volts per
                       Frequency                             meter)
                                                       -----------------
                                                          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
------------------------------------------------------------------------
Note.--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 
Gulfstream G-1159, G-1159A, G-1159B series airplanes modified by 
Garrett Aviation Services to incorporate dual Electronic Primary Flight 
Display Systems. Should Garrett Aviation Services apply at a later date 
for a supplemental type certificate to modify any other model included 
on Type Certificate No. A12EA 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 the Gulfstream G-1159, G-1159A, G-1159B series airplanes modified by 
Garrett Aviation Services. 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 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. 
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 Gulfstream G-1159, G-
1159A, G-1159B series 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.
    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.


[[Page 57650]]


    Issued in Renton, Washington, on November 6, 2001.
Jeff Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-28676 Filed 11-15-01; 8:45 am]
BILLING CODE 4910-13-P