[Federal Register Volume 69, Number 94 (Friday, May 14, 2004)]
[Rules and Regulations]
[Pages 26764-26766]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-10999]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. 278, Special Conditions No. 25-262-SC]


Special Conditions: Gulfstream Model GV-SP and GIV-X; 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 
Corporation Model GV-SP and GIV-X airplanes. These airplanes will have 
novel and unusual design features when compared to the state of 
technology envisioned in the airworthiness standards for transport 
category airplanes. Specifically, these airplanes will use the 
Honeywell EPIC System which includes the Electronic Display System 
(EDS), Air Data System, Inertial Reference System, and Automatic Flight 
Control System. 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 provided by the existing airworthiness standards.

DATES: The effective date of these special conditions is May 14, 2004. 
Comments must be received on or before June 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. NM278, 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. NM278.

FOR FURTHER INFORMATION CONTACT: Joseph Jacobsen, FAA, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-2011; facsimile (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA has determined that notice and opportunity for prior public 
comment 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 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 to 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 
date on the postcard and mail it back to you.

Background

    On August 22, 2000, Gulfstream applied for an amendment to Type 
Certificate No. A12EA to include an updated version of the model GIV 
airplane, called the GIV-X. On October 24, 2000, Gulfstream applied for 
a second amendment to Type Certificate No. A12EA to include an updated 
version of the model GV airplane, called the GV-SP.
    The GIV-X and GV-SP airplanes are both pressurized, low-wing, ``T-
tail'' transport category airplanes with a tricycle landing gear. Both 
carry a maximum of 19 passengers. The GIV-X is powered by two Rolls-
Royce model Tay 611-8C engines; the GV-SP is powered by two BMW-Rolls 
Royce Deutschland model BR700-710C4-11 engines.
    The primary difference between the existing GV and the new GV-SP is 
the installation of an advanced avionics and flight deck display 
suite--the new Honeywell EPIC System--in the GV-SP. The EPIC System 
includes an Electronic Display System, Air Data System, Inertial 
Reference System, and Automatic Flight Control System.
    The primary differences between the existing GIV and the new GIV-X 
are the following features of the GIV-X:
     An advanced avionics and flight deck display suite--the 
EPIC System,
     Airframe aerodynamic changes to increase performance, 
range and economics,
     Derivative Tay 611-8C engines with GV nacelles and thrust 
reversers,
     A new Full Authority Digital Engine Control (FADEC), and
     A modified yaw damper and a new hard-over prevention 
system (HOPS).
    Both the Gulfstream model GIV-X and GV-SP airplanes will utilize 
electrical and electronic systems that perform critical functions. The 
existing airworthiness regulations do not contain adequate or 
appropriate safety standards for protection of these systems from the 
effects of high intensity radiated fields (HIRF) external to the 
airplane. Therefore, these special conditions are proposed.

Type Certification Basis

    Under the provisions of 14 CFR 21.101, Gulfstream must show that 
the model GIV-X and GV-SP airplanes meet the applicable provisions of 
the regulations incorporated by reference in Type Certificate 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 certification basis for the Gulfstream GIV-X airplanes includes 
14 CFR part 25, effective February 1, 1965, including Amendments 25-1 
through 25-101 with the exceptions listed below:

[[Page 26765]]



----------------------------------------------------------------------------------------------------------------
                     Section                                   Title                         Amendment
----------------------------------------------------------------------------------------------------------------
25.21(e)........................................  Proof of compliance............  25-7
25.305..........................................  Strength and deformation.......  25-54, 25-86 **
25.321..........................................  Flight loads--General..........  25-23, 25-86 **
25.333..........................................  Flight maneuvering envelope....  25-0, 25-86 **
25.335(b).......................................  Design airspeeds (speed margin)  25-23
25.341..........................................  Gust and turbulence loads......  25-0, 25-86 **
25.343..........................................  Design fuel and oil loads......  25-18, 25-86 **
25.365..........................................  Pressurized compartment loads..  25-54, 25-87 **
25.373..........................................  Speed control devices..........  25-0, 25-86 **
25.391..........................................  Control surface loads--General.  25-0, 25-86 **
25.427..........................................  Unsymmetrical loads............  25-0, 25-86 **
25.445..........................................  Auxiliary aerodynamic surfaces.  25-0, 25-86 **
25.459..........................................  Special devices................  25-0 *
25.491..........................................  Takeoff run....................  25-0, 25-91 **
25.561..........................................  Emergency landing conditions...  25-23, 25-64 (seats), 25-91
                                                                                    (new structure) **
25.571..........................................  Damage tolerance and fatigue     25-54 (wing and empennage),
                                                   evaluation of structure.         25-96 (fuselage changes) **
25.671..........................................  Control systems--General.......  25-0
25.677(c).......................................  Trim systems...................  25-0
25.693..........................................  Joints.........................  25-0 *
25.695..........................................  Power-boost and power-operated   25-0
                                                   control system.
25.807..........................................  Emergency exits................  25-55 *
25.807(c)(2) and (d)(4).........................  Emergency exits................  25-15 *
25.813(a), (b), (c), (d), and (f)...............  Emergency exit access..........  25-46 *
25.841..........................................  Pressurized cabins.............  25-38, 25-87 **
25.857..........................................  Cargo compartment                25-32 *
                                                   classification.
25.858..........................................  Cargo or baggage compartment     25-54 *
                                                   smoke or fire detection
                                                   systems.
25.963..........................................  Fuel tanks.....................  25-40
25.973..........................................  Fuel tank filler connection....  25-40
25.1013.........................................  Oil tanks......................  25-36
25.1447.........................................  Equipment standards for oxygen   25-41, 25-87 **
                                                   dispensing units.
25.1517.........................................  Rough air speed, VRA...........  25-86 (new paragraph--NA) *
25.1557.........................................  Miscellaneous markings and       25-38 *
                                                   placards.
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* These systems have no changes from the basic GIV model; therefore, the paragraphs remain at the original GIV
  certification basis and the later amendment was not adopted. Amendment 25-0 is the original published version
  of Part 25, February 1, 1965.
** Unmodified structure remains in compliance with the earlier amendment listed. New or modified structure is in
  compliance with the later amendment level listed.

    The certification basis for the Gulfstream GV-SP airplanes includes 
14 CFR part 25, effective February 1, 125-38965, including Amendments 
25-1 through 25-98, with the exceptions and limitations specified in 
Type Certificate A12EA. In addition, the GIV-X and GV-SP certification 
bases include certain special conditions, exemptions, and equivalent 
safety findings that are not relevant to these special conditions.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25, as amended) do not contain adequate 
or appropriate safety standards because of novel or unusual design 
features, special conditions are prescribed under the provisions of 
Sec.  21.16.
    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 models for which 
they are issued. Should the applicant apply for a type certificate to 
modify any other model included on Type Certificate A12EA to 
incorporate the same novel or unusual design feature, the special 
conditions would also apply to the other models under the provisions of 
Sec.  21.101.

Novel or Unusual Design Features

    The Gulfstream Model GV-SP and GIV-X airplanes will incorporate a 
Honeywell EPIC System which will perform certain critical functions. 
The EPIC System includes the Electronic Display System (EDS), Air Data 
System, Inertial Reference System, and Automatic Flight Control System. 
The GIV-X also incorporates a new Full Authority Digital Engine Control 
(FADEC), a modified yaw damper and a new hard-over prevention system 
(HOPS). These systems may be vulnerable to high-intensity radiated 
fields (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 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 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 Gulfstream Model GV-SP and GIV-X 
airplanes. These special conditions require that new electrical and 
electronic systems that perform critical functions, such as the EPIC 
System, 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 and the advent of space and satellite communications, 
coupled with electronic command and control of the

[[Page 26766]]

airplane, the immunity of critical digital avionic/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 the table below for the frequency ranges indicated. Both 
peak and average field strength components from the table below are to 
be demonstrated.

------------------------------------------------------------------------
                                                        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 
Gulfstream GV-SP and GIV-X airplanes. Should Gulfstream apply at a 
later date for design change approval to modify any other model 
included on the same type certificate to incorporate the same or 
similar 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 Gulfstream GV-SP and GIV-X airplanes. It is not a rule of general 
applicability and affects only the applicant which applied to the FAA 
for approval of these features on these airplanes.
    The substance of the special conditions for this airplane 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 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.

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type certification basis for Gulfstream Model GV-SP and GIV-X 
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 May 3, 2004.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-10999 Filed 5-13-04; 8:45 am]
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