This section of the FEDERAL REGISTER

contains regulatory documents having general

applicability and legal effect, most of which

are keyed to and codified in the Code of

Federal Regulations, which is published under

50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by

the Superintendent of Documents. Prices of

new books are listed in the first FEDERAL

REGISTER issue of each week.

Rules and Regulations Federal Register

18939

Vol. 61, No. 84

Tuesday, April 30, 1996

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 23

[Docket No. 131CE, Special Condition 23–

ACE–86]

Special Conditions; Cessna Model 425

Airplanes

AGENCY: Federal Aviation

Administration (FAA), DOT.

ACTION: Final special conditions; request

for comments.

SUMMARY: These special conditions are

issued for the Cessna Model 425

airplanes modified by Modern Avionics,

Inc., Eden Prairie, Minnesota. 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 displays 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.

EFFECTIVE DATE: The effective date of

these special conditions is on

publication in the Federal Register.

Comments must be received on or

before May 30, 1996.

ADDRESSES: Comments may be mailed

in duplicate to: Federal Aviation

Administration, Office of the Assistant

Chief Counsel, ACE–7, Attention: Rules

Docket Clerk, Docket No. 131CE, Room

1558, 601 East 12th Street, Kansas City,

Missouri 64106. All comments must be

marked: Docket No. 131CE. 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:

Ervin Dvorak, Aerospace Engineer,

Standards Office (ACE–110), Small

Airplane Directorate, Aircraft

Certification Service, Federal Aviation

Administration, 601 East 12th Street,

Kansas City, Missouri 64106; telephone

(816) 426–6941.

SUPPLEMENTARY INFORMATION:

Comments Invited

Although this action is in the form of

a final rule that involves requirements

affecting flight safety, and, thus, was not

preceded by notice and an opportunity

for public comment, comments are

invited on these special conditions.

Interested persons are invited to

submit such written data, views, or

arguments as they may desire.

Communications should identify the

regulatory docket and 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 submitted will be available in

the rules docket for examination by

interested parties, 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 this request,

must include a self-addressed and

stamped postcard on which the

following statement is made:

‘‘Comments to Docket No. 131CE.’’ The

postcard will be date stamped and

returned to the commenter.

Background

On March 8, 1996, Modern Avionics,

Inc., 10000 Flying Cloud Drive, Eden

Prairie, Minnesota 55347, made an

application to the FAA for a

supplemental type certificate (STC) for

the Cessna Model 425 airplanes. The

proposed modification incorporates a

novel or unusual design feature, such as

digital avionics consisting of an

electronic flight instrument system

(EFIS), that is vulnerable to HIRF

external to the airplane.

Type Certification Basis

The type certification basis for the

Cessna Model 425 Airplanes is given in

Type Certification Data Sheet No. A7CE

plus the following:

§ 23.1301 of Amendment 23–20;

§§ 23.1309, 23.1311, and 23.1321 of

Amendment 23–41; and § 23.1322 of

Amendment 23–43; exemptions, if any;

and the special conditions adopted by

this rulemaking action.

Discussion

The FAA may issue and amend

special conditions, as necessary, as part

of the type certification basis if the

Administrator finds that the

airworthiness standards, designed

according to § 21.101(b), 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 to establish a level

of safety equivalent to that established

in the regulations. Special conditions

are normally issued according to

§ 11.49, effective October 25, 1989, after

public notice, as required by §§ 11.28

and 11.29(b), and become a part of the

type certification basis in accordance

with § 21.101(b)(2).

Modern Avionics, 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

electronic systems, 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
18940 Federal Register / Vol. 61, No. 84 / Tuesday, April 30, 1996 / Rules and Regulations

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

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:

FIELD STRENGTH VOLTS/METER

Frequency Peak Average

10–100 KHz ...................... 50 50

100–500 ............................ 60 60

500–2000 .......................... 70 70

2–30 MHz .......................... 200 200

30–70 ................................ 30 30

70–100 .............................. 30 30

100–200 ............................ 150 33

200–400 ............................ 70 70

400–700 ............................ 4020 935

700–1000 .......................... 1700 170

1–2 GHz ............................ 5000 990

2–4 .................................... 6680 840

4–6 .................................... 6850 310

FIELD STRENGTH VOLTS/METER—

Continued

Frequency Peak Average

6–8 .................................... 3600 670

8–12 .................................. 3500 1270

12–18 ................................ 3500 360

18–40 ................................ 2100 750

or,

(2) The applicant may demonstrate by

a system test and analysis that the

electrical electronic systems that

perform critical functions can withstand

a minimum threat of 100 volts per

meter, peak 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

electrical and/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.

Conclusion

In view of the design features

discussed for the Cessna Model 425

Airplanes, the following special

conditions are issued. This action is not

a rule of general applicability and

affects only those applicants who apply

to the FAA for approval of these features

on these airplanes.

The substance of these special

conditions has been subject to the notice

and public comment procedure in

several prior rulemaking actions. For

example, the Dornier 228–200 (53 FR

14782, April 26, 1988), the Cessna

Model 525 (56 FR 49396, September 30,

1991), and the Beech Models 200, A200,

and B200 airplanes (57 FR 1220, January

13, 1992). It is unlikely that additional

public comment would result in any

significant change from those special

conditions already issued and

commented on. For these reasons, and

because a delay would significantly

affect the applicant’s installation of the

system and 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

without notice. Therefore, these special

conditions are being made effective

upon publication in the Federal

Register. However, as previously

indicated, interested persons are invited

to comment on these special conditions

if they so desire

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, 44701,

44702, and 44704; 14 CFR 21.16 and 21.101;

and 14 CFR 11.28 and 11.49.

Adoption of 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 the modified

Cessna Model 425 Airplanes:

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.
Federal Register / Vol. 61, No. 84 / Tuesday, April 30, 1996 / Rules and Regulations 18941

Issued in Kansas City, Missouri on April

15, 1996.

Henry A. Armstrong,

Acting Manager, Small Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 96–10673 Filed 4–29–96; 8:45 am]

BILLING CODE 4910–13–M

14 CFR Part 97

[Docket No. 28549; Amdt. No. 1725]

Standard Instrument Approach

Procedures; Miscellaneous

Amendments

AGENCY: Federal Aviation

Administration (FAA), DOT.

ACTION: Final rule.

SUMMARY: This amendment establishes,

amends, suspends, or revokes Standard

Instrument Approach Procedures

(SIAPs) for operations at certain

airports. These regulatory actions are

needed because of changes occurring in

the National Airspace System, such as

the commissioning of new navigational

facilities, addition of new obstacles, or

changes in air traffic requirements.

These changes are designed to provide

safe and efficient use of the navigable

airspace and to promote safe flight

operations under instrument flight rules

at the affected airports.

DATES: An effective date for each SIAP

is specified in the amendatory

provisions.

Incorporation by reference-approved

by the Director of the Federal Register

on December 31, 1980, and reapproved

as of January 1, 1982.

ADDRESSES: Availability of matter

incorporated by reference in the

amendment is as follows:

For Examination—1. FAA Rules

Docket, FAA Headquarters Building,

800 Independence Avenue, SW.,

Washington, DC 20591;

2. The FAA Regional Office of the

region in which affected airport is

located; or

3. The Flight Inspection Area Office

which originated the SIAP.

For Purchase—Individual SIAP

copies may be obtained from:

1. FAA Public Inquiry Center (APA–

200), FAA Headquarters Building, 800

Independence Avenue, SW.,

Washington, DC 20591; or

2. The FAA Regional Office of the

region in which the affected airport is

located.

By Subscription—Copies of all SIAPs,

mailed once every 2 weeks, are for sale

by the Superintendent of Documents,

US Government Printing Office,

Washington, DC 20402.

FOR FURTHER INFORMATION CONTACT:

Paul J. Best, Flight Procedures

Standards Branch (AFS–420), Technical

Programs Division, Flight Standards

Service, Federal Aviation

Administration, 800 Independence

Avenue, SW., Washington, DC 20591;

telephone (202) 267–8277.

SUPPLEMENTARY INFORMATION: This

amendment to part 97 of the Federal

Aviation Regulations (14 CFR part 97)

establishes, amends, suspends, or

revokes Standard Instrument Approach

Procedures (SIAPs). The complete

regulatory description on each SIAP is

contained in the appropriate FAA Form

8260 and the National Flight Data

Center (FDC)/Permanent (P) Notices to

Airmen (NOTAM) which are

incorporated by reference in the

amendment under 5 U.S.C. 552(a), 1

CFR part 51, and § 97.20 of the Federal

Aviation Regulations (FAR). Materials

incorporated by reference are available

for examination or purchase as stated

above.

The large number of SIAPs, their

complex nature, and the need for a

special format make their verbatim

publication in the Federal Register

expensive and impractical. Further,

airmen do not use the regulatory text of

the SIAPs, but refer to their graphic

depiction of charts printed by

publishers of aeronautical materials.

Thus, the advantages of incorporation

by reference are realized and

publication of the complete description

of each SIAP contained in FAA form

documents is unnecessary. The

provisions of this amendment state the

affected CFR (and FAR) sections, with

the types and effective dates of the

SIAPs. This amendment also identifies

the airport, its location, the procedure

identification and the amendment

number.

The Rule

This amendment to part 97 of the

Federal Aviation Regulations (14 CFR

part 97) establishes, amends, suspends,

or revokes SIAPs. For safety and

timeliness of change considerations, this

amendment incorporates only specific

changes contained in the content of the

following FDC/P NOTAM for each

SIAP. The SIAP information in some

previously designated FDC/Temporary

(FDC/T) NOTAMs is of such duration as

to be permanent.With conversion to

FDC/P NOTAMs, the respective FDC/T

NOTAMs have been cancelled.

The FDC/P NOTAMs for the SIAPs

contained in this amendment are based

on the criteria contained in the U.S.

Standard for Terminal Instrument

Approach Procedures (TERPS). In

developing these chart changes to SIAPs

by FDC/P NOTAMs, the TERPS criteria

were applied to only these specific

conditions existing at the affecting

airports. All SIAP amendments in this

rule have been previously issued by the

FAA in a National Flight Data Center

(FDC) Notice to Airmen (NOTAM) as an

emergency action of immediate flight

safety relating directly to published

aeronautical charts. The circumstances

which created the need for all these

SIAP amendments requires making

them effective in less than 30 days.

Further, the SIAPs contained in this

amendment are based on the criteria

contained in the TERPS. Because of the

close and immediate relationship

between these SIAPs and safety in air

commerce, I find that notice and public

procedure before adopting these SIAPs

are impracticable and contrary to the

public interest and, where applicable,

that good cause exists for making these

SIAPs effective in less than 30 days.

Conclusion

The FAA has determined that this

regulation only involves an established

body of technical regulations for which

frequent and routine amendments are

necessary to keep them operationally

current. It, therefore—(1) is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under DOT

Regulatory Policies and Procedures (44

FR 11034; February 26, 1979); and (3)

does not warrant preparation of a

regulatory evaluation as the anticipated

impact is so minimal. For the same

reason, the FAA certifies that this

amendment will not have a significant

economic impact on a substantial

number of small entities under the

criteria of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 97

Air Traffic Control, Airports,

Navigation (Air).

Issued in Washington, DC on April 19,

1996.

Thomas C. Accardi,

Director, Flight Standards Service.

Adoption of the Amendment

Accordingly, pursuant to the

authority delegated to me, part 97 of the

Federal Aviation Regulations (14 (CFR

part 97) is amended by establishing,

amending, suspending, or revoking

Standard Instrument Approach

Procedures, effective at 0901 UTC on

the dates specified, as follows:

PART 97—STANDARD INSTRUMENT

APPROACH PROCEDURES

1. The authority citation for part 97 is

revised to read as follows: