57728 Federal Register / Vol. 70, No. 191 / Tuesday, October 4, 2005 / Rules and Regulations 

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 cockpitinstalled 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 indicated in the 

following table for the frequency ranges 

indicated. Both peak and average field 

strength components from the table are 

to be demonstrated. 

Frequency 

Field strength 

(volts per 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 

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 Boeing 

Model 720B airplane, modified by 

Flight Test Associates, Inc. Should 

Flight Test Associates, Inc., 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 as 

under the provisions of 14 CFR 21.101. 

Conclusion 

This action affects only certain design 

features on the Boeing Model 720B 

airplane modified by Flight Test 

Associates, Inc. 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 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 record keeping 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 Boeing Model 720B airplane, 

modified by Flight Test Associates, Inc: 

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. 

Kalene C. Yanamura, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 05–19858 Filed 10–3–05; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. NM328, Special Conditions No. 

25–298–SC] 

Special Conditions: Raytheon Model 

BH125 Series 400A and 600A 

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 Raytheon Model BH125 

Series 400A and 600A 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. The modification 

incorporates the installation of dual 

Honeywell Model AM–250 digital 

altimeters. 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 September 12, 

2005. Comments must be received on or 

before November 3, 2005. 

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. 

NM328, 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. NM328. Comments may be 

inspected in the Rules Docket 

weekdays, except Federal holidays, 

between 7:30 a.m. and 4 p.m. 

Federal Register / Vol. 70, No. 191 / Tuesday, October 4, 2005 / Rules and Regulations 57729 

FOR FURTHER INFORMATION CONTACT: Mr. 

Greg Dunn, FAA, Airplane & Flight 

Crew Interface Branch, ANM–111, 

Transport Airplane Directorate, Aircraft 

Certification Service, 1601 Lind Avenue 

SW., Renton, Washington, 98055–4056; 

telephone (425) 227–2799; facsimile 

(425) 227–1320. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

The FAA has determined that notice 

and opportunity for prior public 

comment hereon is unnecessary, as 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 in 

light of the comments received. 

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 February 17, 2005, Flight Test 

Associates, Inc., of Mojave, California, 

applied to the FAA, Los Angeles 

Aircraft Certification Office for a 

supplemental type certificate (STC) to 

modify Raytheon Model BH125 Series 

400A and 600A airplanes. The proposed 

modification incorporates the 

installation of dual Honeywell Model 

AM–250 digital altimeters as primary 

instruments. The information presented 

is flight critical. The altimeters installed 

in the airplanes have the potential to be 

vulnerable to high-intensity radiated 

fields (HIRF) external to the airplanes. 

Type Certification Basis 

Under the provisions of 14 CFR 

21.101, Flight Test Associates, Inc., 

must show that the airplanes as 

changed, continues 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. A3EU 

include Civil Aeronautics Manual 4b, as 

amended by Amendments 4b–1 through 

4b–11. 

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 Raytheon 

Model BH125 Series 400A and 600A 

airplanes, because of a novel or unusual 

design feature, special conditions are 

prescribed under the provisions of 

§ 21.16. 

In addition to the applicable 

airworthiness regulations and special 

conditions, the Raytheon Model BH125 

Series 400A and 600A airplanes must 

comply with the fuel vent and exhaust 

emission requirements of 14 CFR part 

24 and the noise certification 

requirements of 14 CFR part 36. 

Special conditions, as defined in 14 

CFR 11.19, are issued in accordance 

with § 11.38 and become part of the type 

certification basis in accordance with 

§ 21.101. 

Special conditions are initially 

applicable to the model for which they 

are issued. Should Flight Test 

Associates, Inc., apply at a later date for 

an STC 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 § 21.101. 

Novel or Unusual Design Features 

As noted earlier, the Raytheon Model 

BH125 Series 400A and 600A airplanes 

modified by Flight Test Associates, Inc., 

will incorporate new dual primary 

altimeters that will perform critical 

functions. These systems may be 

vulnerable to 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, 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 equivalent to that intended by 

the regulations incorporated by 

reference, special conditions are needed 

for the Raytheon Model BH125 Series 

400A and 600A airplanes. These special 

conditions require that new primary 

altimeters 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/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 cockpitinstalled 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 indicated in the 

following table for the frequency ranges 

indicated. Both peak and average field 

57730 Federal Register / Vol. 70, No. 191 / Tuesday, October 4, 2005 / Rules and Regulations 

strength components from the table are 

to be demonstrated. 

Frequency 

Field strength 

(volts per 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 

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 Raytheon 

Model BH125 Series 400A and 600A 

airplanes, modified by Flight Test 

Associates, Inc. Should Flight Test 

Associates, Inc., 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 as under the 

provisions of 14 CFR 21.101. 

Conclusion 

This action affects only certain design 

features on the Raytheon Model BH125 

Series 400A and 600A airplanes 

modified by Flight Test Associates, Inc. 

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 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 record keeping 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 modified Raytheon Model BH125 

Series 400A and 600A airplanes, 

modified by Flight Test Associates, Inc.: 

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. 

Kalene C. Yanamura, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 05–19859 Filed 10–3–05; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. NM329; Special Conditions No. 

25–300–SC] 

Special Conditions: Dassault-Aviation 

Mystere-Falcon 50 Airplanes; HighIntensity Radiated Fields (HIRF) 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions; request 

for comments. 

SUMMARY: These special conditions are 

issued for Dassault-Aviation MystereFalcon 50 airplanes modified by 

Premier Air Center. 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 

Universal Avionics EFI–890 Electronic 

Flight Displays and Rockwell Collins 

AHS–3000A Attitude Heading 

Reference Systems (AHRS) 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 23, 

2005. Comments must be received on or 

before November 3, 2005. 

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. NM329, 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. NM329. 

FOR FURTHER INFORMATION CONTACT: Greg 

Dunn, FAA, Airplane and Flight Crew 

Interface Branch, ANM–111, Transport 

Airplane Directorate, Aircraft 

Certification Service, 1601 Lind Avenue 

SW., Renton, Washington 98055–4056; 

telephone (425) 227–2799; facsimile 

(425) 227–1320. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

The FAA has determined that notice 

and opportunity for prior public 

comment is 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