[Federal Register Volume 66, Number 138 (Wednesday, July 18, 2001)]
[Rules and Regulations]
[Pages 37408-37410]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-17961]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM192, Special Conditions No. 25-181-SC]


Special Conditions: Raytheon Model Hawker 800XP Airplane; High-
Intensity Radiated Fields

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for Raytheon Aircraft 
Company Model Hawker 800XP airplanes modified to incorporate the 
Collins Proline 21 avionics system. These modified airplanes will have 
novel and unusual design features when compared to the state of 
technology envisioned in the airworthiness standards for transport 
category airplanes. The modification incorporates the installation of a 
four tube active matrix liquid crystal display Electronic Flight 
Information System (EFIS) with an Engine Indicating System (EIS), 
autopilot with integral mach trim capability, new air data computers, 
and new Attitude and Heading Reference System (AHRS) with solid state 
sensors. The applicable airworthiness standards 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 July 6, 2001. 
Comments must be received on or before August 17, 2001.

ADDRESSES: Comments on these special conditions may be mailed in 
duplicate to: Federal Aviation Administration, Transport Airplane 
Directorate, Attn: Rules Docket (ANM-113), Docket No. NM192, 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. NM192. Comments may be inspected in the 
Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 
4:00 p.m.

FOR FURTHER INFORMATION CONTACT: Mark Quam, FAA, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington, 98055-4056; 
telephone (425) 227-2145; 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 issuance of the approval 
design 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.

Comments Invited

    Interested persons are invited to submit such written data, views, 
or arguments as they may desire. Communications should identify the 
regulatory docket or special conditions 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. These 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. Commenters wishing the FAA to acknowledge receipt of their 
comments submitted in response to these special conditions must include 
a self-addressed, stamped postcard on which the following statement is 
made: ``Comments to Docket No. NM192.'' The postcard will be date 
stamped and returned to the commenter.

Background

    On August 4, 1998, Raytheon Aircraft Company, PO Box 85, Wichita, 
Kansas 67201-0085, applied for a supplemental type certificate to 
modify Raytheon Aircraft Company Model Hawker 800XP airplanes listed on 
Type Certificate No. A21EA. The Model Hawker 800XP is a twin engine 
transport airplane. It has an executive interior and is capable of 
carrying two flight crewmembers and up to fifteen passengers. This 
model is powered by two aft mounted Allied Signal TFE 731-5BR engines. 
The modification incorporates the installation of the Rockwell Collins 
Proline 21 avionics system which includes a four tube active matrix 
liquid crystal display Electronic Flight Information System (EFIS) with 
an Engine Indicating System (EIS) that display critical flight 
parameters to the flightcrew. These systems can be susceptible to 
disruption to command and/or 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, Raytheon must show that the 
Raytheon Model Hawker 800XP airplanes, as changed, continue to meet the 
applicable provisions of the regulations incorporated by reference in 
Type Certificate No. A3EU, 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. A21EA are as follows: the 
certification basis for the modified Raytheon Model Hawker 800XP 
airplane includes the British Civil Airworthiness Requirements (CAR) 
10, and specific additional requirements of 14 CFR part 25, as listed 
in the Type Certificate Data Sheet (TCDS) No. A3EU.
    If the Administrator finds that the applicable airworthiness 
regulations

[[Page 37409]]

(i.e., part 25) do not contain adequate or appropriate safety standards 
for the Raytheon Model Hawker 800XP airplane 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 Raytheon Model Hawker 800XP airplane 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 Sec. 11.19, are issued in 
accordance with Sec. 11.38 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 Raytheon apply for approval 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

    The Raytheon Model Hawker 800XP airplane will incorporate the 
following novel or unusual design features: the Rockwell Collins 
Proline 21 avionics system which includes a four tube active matrix 
liquid crystal display Electronic Flight Information System (EFIS) with 
an Engine Indicating System (EIS) that display critical flight 
parameters to the flightcrew. These systems can be susceptible to 
disruption to command and/or 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.

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 avionic/electronic 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 equivalent to that 
intended by the regulations incorporated by reference, special 
conditions are needed for the Raytheon Model Hawker 800XP as modified 
by Raytheon. These special conditions require that new avionic/
electronic and electrical systems, such as the AHRS and EFIS 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 paragraph 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.
    1. 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 meter)
                   Frequency                   -------------------------
                                                    Peak       Average
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10 kHz-100kHz.................................           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.
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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.

Applicability

    As discussed above, these special conditions are applicable to 
Raytheon Model Hawker 800XP airplane modified

[[Page 37410]]

by the Raytheon Aircraft Company. Should Raytheon apply at a later date 
for approval of a design change 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 novel or unusual design features 
on Raytheon Model Hawker 800XP airplane modified by the Raytheon 
Aircraft Company. 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 the special conditions for this airplane 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 type certification basis for Raytheon Model Hawker 800XP airplanes 
modified by:
    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 July 6, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-17961 Filed 7-17-01; 8:45 am]
BILLING CODE 4910-13-P