72070 Federal Register / Vol. 70, No. 230 / Thursday, December 1, 2005 / Rules and Regulations 

the design and installation of these 

systems. The accepted maximum energy 

levels in which civilian airplane system 

installations must be capable of 

operating safely are based on surveys 

and analysis of existing radio frequency 

emitters. These special conditions 

require that the airplane be evaluated 

under these energy levels for the 

protection of the electronic system and 

its associated wiring harness. These 

external threat levels, which are lower 

than previous required values, are 

believed to represent the worst case to 

which an airplane would be exposed in 

the operating environment. 

These special conditions require 

qualification of systems that perform 

critical functions, as installed in aircraft, 

to the defined HIRF environment in 

paragraph 1 or, as an option, to a fixed 

value using laboratory tests in paragraph 

2, as follows: 

(1) The applicant may demonstrate 

that the operation and operational 

capability of the installed electrical and 

electronic systems that perform critical 

functions are not adversely affected 

when the aircraft is exposed to the HIRF 

environment defined below: 

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 root-mean-square (rms) values. 

or, 

(2) The applicant may demonstrate by 

a system test and analysis that the 

electrical and electronic systems that 

perform critical functions can withstand 

a minimum threat of 100 volts per 

meter, electrical field strength, from 10 

kHz to 18 GHz. When using this test to 

show compliance with the HIRF 

requirements, no credit is given for 

signal attenuation due to installation. 

A preliminary hazard analysis must 

be performed by the applicant, for 

approval by the FAA, to identify either 

electrical or electronic systems that 

perform critical functions. The term 

‘‘critical’’ means those functions, whose 

failure would contribute to, or cause, a 

failure condition that would prevent the 

continued safe flight and landing of the 

airplane. The systems identified by the 

hazard analysis that perform critical 

functions are candidates for the 

application of HIRF requirements. A 

system may perform both critical and 

non-critical functions. Primary 

electronic flight display systems, and 

their associated components, perform 

critical functions such as attitude, 

altitude, and airspeed indication. The 

HIRF requirements apply only to critical 

functions. 

Compliance with HIRF requirements 

may be demonstrated by tests, analysis, 

models, similarity with existing 

systems, or any combination of these. 

Service experience alone is not 

acceptable since normal flight 

operations may not include an exposure 

to the HIRF environment. Reliance on a 

system with similar design features for 

redundancy as a means of protection 

against the effects of external HIRF is 

generally insufficient since all elements 

of a redundant system are likely to be 

exposed to the fields concurrently. 

Applicability 

As discussed above, these special 

conditions are applicable to the Cessna 

Model 510 Mustang airplane. Should 

Cessna apply at a later date for a 

supplemental type certificate to modify 

any other model on the same type 

certificate to incorporate the same novel 

or unusual design feature, the special 

conditions would apply to that model as 

well under the provisions of § 21.101. 

Conclusion 

This action affects only certain novel 

or unusual design features on one model 

of airplane. 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 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. 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 23 

Aircraft, Aviation safety, Signs and 

symbols. 

Citation 

■ The authority citation for these 

special conditions is as follows: 

Authority: 49 U.S.C. 106(g), 40113 and 

44701; 14 CFR 21.16 and 21.101; and 14 CFR 

11.38 and 11.19. 

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 Cessna Model 510 Mustang 

airplane. 

1. Protection of Electrical and 

Electronic Systems from High Intensity 

Radiated Fields (HIRF). Each system 

that performs critical functions must be 

designed and installed to ensure that the 

operations, and operational capabilities 

of these systems to perform critical 

functions, are not adversely affected 

when the airplane is exposed to HIRF 

external to the airplane. 

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 Kansas City, Missouri on 

November 17, 2005. 

David R. Showers, 

Manager, Small Airplane Directorate, Aircraft 

Certification Service. 

[FR Doc. 05–23523 Filed 11–30–05; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 23 

[Docket No. CE235, Special Condition 23–

175–SC] 

Special Conditions; New Piper Aircraft, 

Inc.; PA–34; Protection of Systems for 

High Intensity Radiated Fields (HIRF) 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions; request 

for comments. 

SUMMARY: These special conditions are 

issued to the New Piper Aircraft, Inc., 

Vero Beach, Florida, for a type design 

Federal Register / Vol. 70, No. 230 / Thursday, December 1, 2005 / Rules and Regulations 72071 

change for the PA–34 model airplanes. 

These airplanes will have novel and 

unusual design features when compared 

to the state of technology envisaged in 

the applicable airworthiness standards. 

These novel and unusual design 

features include the installation of 

electronic flight instrument system 

(EFIS) displays Model 700–00006–

XXX(), manufactured by Avidyne 

Corporation, Inc. for which the 

applicable regulations do not contain 

adequate or appropriate airworthiness 

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 

the airworthiness standards applicable 

to these airplanes. 

DATES: The effective date of these 

special conditions is November 17, 

2005. Comments must be received on or 

before January 3, 2006. 

ADDRESSES: Comments may be mailed 

in duplicate to: Federal Aviation 

Administration, Regional Counsel, 

ACE–7, Attention: Rules Docket Clerk, 

Docket No. CE235, Room 506, 901 

Locust, Kansas City, Missouri 64106. All 

comments must be marked: Docket No. 

CE235. 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: Wes 

Ryan, Aerospace Engineer, Standards 

Office (ACE–110), Small Airplane 

Directorate, Aircraft Certification 

Service, Federal Aviation 

Administration, 901 Locust, Room 301, 

Kansas City, Missouri 64106; telephone 

(816) 329–4127. 

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 notice 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. 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. Commenters wishing the FAA to 

acknowledge receipt of their comments 

submitted in response to this notice 

must include a self-addressed, stamped 

postcard on which the following 

statement is made: ‘‘Comments to 

Docket No. CE235.’’ The postcard will 

be date stamped and returned to the 

commenter. 

Background 

The New Piper Aircraft, Inc., Vero 

Beach, Florida, has made application to 

revise the type design of the PA–34 

model airplanes. The model is currently 

approved under the type certification 

basis listed on Type Certificate Data 

Sheet (TCDS) A7SO. The proposed 

modification incorporates a novel or 

unusual design feature, such as digital 

avionics consisting of an EFIS that is 

vulnerable to HIRF external to the 

airplane. 

Type Certification Basis 

Under the provisions of 14 CFR part 

21, § 21.101, New Piper Aircraft, Inc, 

must show that affected airplane 

models, as changed, continue to meet 

the applicable provisions of the 

regulations identified on the appropriate 

TCDS. In addition, the type certification 

basis of the airplanes embodying this 

modification will include the additional 

certification basis for installation of the 

Avidyne Entegra EFIS: 14 CFR part 23 

regulations FAR 23.301, 23.337, 23.341, 

23.473, 23.561, 23.607, 23.611, as 

amended by Amdt. 23–48; FAR 23.305, 

23.613, 23.773, 23.1525, 23.1549 as 

amended by Amdt. 23–45; FAR 23.777, 

23.1191, 23.1337 as amended by Amdt. 

23–51; FAR 23.867, 23.1303, 23.1307, 

23.1309, 23.1311, 23.1321, 23.1323, 

23.1329, 23.1351, 23.1353, 23.1359, 

23.1361, 23.1365, 23.1431 as amended 

by Amdt. 23–49; FAR 23.1305 as 

amended by Amdt. 23–52; FAR 23.1322, 

23.1331, 23.1357 as amended by Amdt. 

23–43; FAR 23.1325, 23.1543, 23.1545, 

23.1555, 23.1563, 23.1581, 23.1583, 

23.1585 as amended by Amdt. 23–50; 

FAR 23.1523 as amended by Amdt. 23–

34; FAR 23.1529 as amended by Amdt. 

23–26; and the special conditions 

adopted by this rulemaking action. 

Discussion 

If the Administrator finds that the 

applicable airworthiness standards do 

not contain adequate or appropriate 

safety standards because of novel or 

unusual design features of an airplane, 

special conditions are prescribed under 

the provisions of § 21.16. 

Special conditions, as appropriate, as 

defined in § 11.19, are issued in 

accordance with § 11.38 after public 

notice and become part of the type 

certification basis in accordance with 

§ 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 already 

included on the same type certificate to 

incorporate the same novel or unusual 

design feature, the special conditions 

would also apply to the other model 

under the provisions of § 21.101. 

Novel or Unusual Design Features 

The New Piper Aircraft, Inc plans to 

incorporate certain novel and unusual 

design features into an airplane for 

which the airworthiness standards do 

not contain adequate or appropriate 

safety standards for protection from the 

effects of HIRF. These features include 

EFIS, which are susceptible to the HIRF 

environment, that were not envisaged 

by the existing regulations for this type 

of airplane. 

Protection of Systems From High 

Intensity Radiated Fields (HIRF) 

Recent advances in technology have 

given rise to the application in aircraft 

designs of advanced electrical and 

electronic systems that perform 

functions required for continued safe 

flight and landing. Due to the use of 

sensitive solid-state advanced 

components in analog and digital 

electronics circuits, these advanced 

systems are readily responsive to the 

transient effects of induced electrical 

current and voltage caused by the HIRF. 

The HIRF can degrade electronic 

systems performance by damaging 

components or upsetting system 

functions. 

Furthermore, the HIRF environment 

has undergone a transformation that was 

not foreseen when the current 

requirements were developed. Higher 

energy levels are radiated from 

transmitters that are used for radar, 

radio, and television. Also, the number 

of transmitters has increased 

significantly. There is also uncertainty 

concerning the effectiveness of airframe 

shielding for HIRF. Furthermore, 

coupling to cockpit-installed equipment 

72072 Federal Register / Vol. 70, No. 230 / Thursday, December 1, 2005 / Rules and Regulations 

through the cockpit window apertures is 

undefined. 

The combined effect of the 

technological advances in airplane 

design and the changing environment 

has resulted in an increased level of 

vulnerability of electrical and electronic 

systems required for the continued safe 

flight and landing of the airplane. 

Effective measures against the effects of 

exposure to HIRF must be provided by 

the design and installation of these 

systems. The accepted maximum energy 

levels in which civilian airplane system 

installations must be capable of 

operating safely are based on surveys 

and analysis of existing radio frequency 

emitters. These special conditions 

require that the airplane be evaluated 

under these energy levels for the 

protection of the electronic system and 

its associated wiring harness. These 

external threat levels, which are lower 

than previous required values, are 

believed to represent the worst case to 

which an airplane would be exposed in 

the operating environment. 

These special conditions require 

qualification of systems that perform 

critical functions, as installed in aircraft, 

to the defined HIRF environment in 

paragraph 1 or, as an option to a fixed 

value using laboratory tests, in 

paragraph 2, as follows: 

(1) The applicant may demonstrate 

that the operation and operational 

capability of the installed electrical and 

electronic systems that perform critical 

functions are not adversely affected 

when the aircraft is exposed to the HIRF 

environment defined below: 

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 root-mean-square (rms) values. 

or, 

(2) The applicant may demonstrate by 

a system test and analysis that the 

electrical and electronic systems that 

perform critical functions can withstand 

a minimum threat of 100 volts per 

meter, electrical field strength, from 10 

kHz to 18 GHz. When using this test to 

show compliance with the HIRF 

requirements, no credit is given for 

signal attenuation due to installation. 

A preliminary hazard analysis must 

be performed by the applicant, for 

approval by the FAA, to identify either 

electrical or electronic systems that 

perform critical functions. The term 

‘‘critical’’ means those functions whose 

failure would contribute to, or cause, a 

failure condition that would prevent the 

continued safe flight and landing of the 

airplane. The systems identified by the 

hazard analysis that perform critical 

functions are candidates for the 

application of HIRF requirements. A 

system may perform both critical and 

non-critical functions. Primary 

electronic flight display systems, and 

their associated components, perform 

critical functions such as attitude, 

altitude, and airspeed indication. The 

HIRF requirements apply only to critical 

functions. 

Compliance with HIRF requirements 

may be demonstrated by tests, analysis, 

models, similarity with existing 

systems, or any combination of these. 

Service experience alone is not 

acceptable since normal flight 

operations may not include an exposure 

to the HIRF environment. Reliance on a 

system with similar design features for 

redundancy as a means of protection 

against the effects of external HIRF is 

generally insufficient since all elements 

of a redundant system are likely to be 

exposed to the fields concurrently. 

Applicability 

As discussed above, these special 

conditions are applicable to New Piper 

PA–34 model airplanes. 

Conclusion 

This action affects only certain novel 

or unusual design features on one model 

of airplane. 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 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. 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 23 

Aircraft, Aviation safety, Signs and 

symbols. 

Citation 

■ The authority citation for these 

special conditions is as follows: 

Authority: 49 U.S.C. 106(g), 40113 and 

44701; 14 CFR 21.16 and 21.101; and 14 CFR 

11.38 and 11.19. 

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 New Piper PA–34 model 

airplanes modified by installation of the 

factory optional Avidyne Entegra EFIS 

system. 

1. Protection of Electrical and 

Electronic Systems from High Intensity 

Radiated Fields (HIRF). Each system 

that performs critical functions must be 

designed and installed to ensure that the 

operations, and operational capabilities 

of these systems to perform critical 

functions, are not adversely affected 

when the airplane is exposed to high 

intensity radiated electromagnetic fields 

external to the airplane. 

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 Kansas City, Missouri on 

November 17, 2005. 

David R. Showers, 

Manager, Small Airplane Directorate, Aircraft 

Certification Service. 

[FR Doc. 05–23524 Filed 11–30–05; 8:45 am] 

BILLING CODE 4910–13–P