10482 Federal Register / Vol. 60, No. 38 / Monday, February 27, 1995 / Rules and Regulations

submitted by July 27, 1995. The

geographic certification directorates are:

Federal Aviation Administration, New

England Region, Engine and Propeller

Directorate, 12 New England

Executive Park, Burlington, MA

01803, (617) 238–7100

Federal Aviation Administration,

Central Region, Small Airplane

Directorate, 601 East 12th Street,

Kansas City, MO 64106, (816) 426–

6937

Federal Aviation Administration,

Northwest Mountain Region,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, WA

98055–4056, (206) 227–2159

Federal Aviation Administration,

Southwest Region, Rotorcraft

Directorate, 2601 Meacham

Boulevard, Ft. Worth, TX 76137–

4298, (817) 222–5100

5. If the FAA is informed through a

source other than an application, as

discussed in paragraph 2, that an

applicant may be producing parts in

violation of § 21.303(a), the FAA will

investigate and take action as necessary

and appropriate to enforce and ensure

future compliance with the rule.

6. Nothing in this policy precludes

the FAA from taking action for

violations of regulations or laws other

than § 21.303(a), or referral to another

government agency for appropriate

action.

Issued in Washington, DC, on February 17,

1995.

Thomas E. McSweeny,

Director, Aircraft Certification Service.

[FR Doc. 95–4760 Filed 2–23–95; 8:45 am]

BILLING CODE 4910–13–M

14 CFR Part 25

[Docket No. NM–107; Special Conditions

No. 25–ANM–95]

Special Conditions; Modified Cessna

550 Series Airplanes; High Intensity

Radiated Fields (HIRF)

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final special conditions with

request for comments.

SUMMARY: These special conditions are

issued for Cessna 550 series airplanes

modified by Elliott Aviation Technical

Products Development, Inc. of Moline

Illinois. These airplanes are equipped

with digital head-up display (HUD)

systems that perform critical functions.

The applicable type certification

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

provide the additional safety standards

that the Administrator considers

necessary to ensure that the critical

functions that these systems perform are

maintained when the airplane is

exposed to HIRF.

DATES: The effective date of these

special conditions is February 13, 1995.

Comments must be received on or

before April 13, 1995.

ADDRESSES: Comments on these special

conditions may be mailed in duplicate

to: Federal Aviation Administration,

Transport Airplane Directorate (ANM–

100), Attn: Docket No. NM–107, 1601

Lind Avenue SW., Renton, WA 98055–

4056; or delivered in duplicate to the

Transport Airplane Directorate at the

above address. Comments must be

marked: Docket No. NM–107.

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:

Michael Zielinski, FAA,

Standardization Branch, ANM–113,

Transport Airplane Directorate, Aircraft

Certification Service, 1601 Lind Avenue

SW., Renton, WA 98055–4056;

telephone (206) 227–2279.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA has determined that good

cause exists for making these special

conditions effective upon issuance;

however, 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 submitted will be available in

the 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. Persons wishing the FAA to

acknowledge receipt of their comments

submitted in response to this request

must submit with those comments a

self-addressed, stamped postcard on

which the following statement is made:

‘‘Comments to docket No. NM–107.’’

The postcard will be date stamped and

returned to the commenter.

Background

On October 25, 1994, Elliott Aviation

Technical Products Development, Inc.

of Moline, Illinois, applied for a

supplemental type certificate to modify

Cessna 550 series airplanes. The Cessna

550 is a business jet with two aftmounted turbofan engines. The airplane

can carry two pilots and up to 11

passengers, depending on the exit and

interior configuration, and is capable of

operating to an altitude of 43,000 feet.

The proposed modification incorporates

the installation of digital avionics

consisting of a head-up display (HUD)

system that is potentially vulnerable to

HIRF external to the airplane.

Supplemental Type Certification Basis

Under the provisions of § 21.101 of

the FAR, Elliott Aviation Technical

Products Development, Inc. must show

that the modified Cessna 550 series

airplanes continue to meet the

applicable provisions of the regulations

incorporated by reference in Type

Certificate No. A22CE, 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. A22CE

include the following: Part 25 of the

Federal Aviation Regulations (FAR),

dated February 1, 1965, including

Amendments 25–1 through 25–17. In

addition the following sections of the

FAR apply to the HUD installation:

§§ 25.1303(b) and 25.1322, as amended

through Amendment 25–38; §§ 25.1309,

25.1321 (a), (b), (d), and (e), 25.1333,

and 25.1335, as amended by

Amendment 25–41. These special

conditions will form an additional part

of the supplemental type certification

basis.

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 Cessna 550 series

airplanes because of a novel or unusual

design feature, 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, as appropriate, are

issued in accordance with § 11.49 of the

FAR after public notice, as required by

§§ 11.28 and 11.29, 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
Federal Register / Vol. 60, No. 38 / Monday, February 27, 1995 / Rules and Regulations 10483

are issued. Should the applicant apply

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,

the special conditions would also apply

to the other model under the provisions

of § 21.101(a)(1).

Discussion

There is no specific regulation that

address 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 Cessna 550 series airplanes that

would require that new technology

electrical and electronic systems, such

as the HUD, 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, such as the

HUD, 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 paragraphs 1 or 2 below:

1. A minimum threat of 100 volts per

meter peak 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 following field strengths for the

frequency ranges indicated.

Frequency Peak

(V/M)

Average

(V/M)

10 KHz–100 KHz .......... 50 50

100 KHz–500 KHz ........ 60 60

500 KHz– 2 MHz .......... 70 70

2 MHz–30 MHz ............ 200 200

30 MHz–70 MHz .......... 30 30

70 MHz–100 MHz ........ 30 30

100 MHz–200 MHz ...... 150 33

200 MHz–400 MHz ...... 70 70

400 MHz–700 MHz ...... 4,020 935

700 MHz–1 GHz ........... 1,700 170

1 GHz–2 GHz ............... 5,000 990

2 GHz–4 GHz ............... 6,680 840

4 GHz–6 GHz ............... 6,850 310

6 GHz–8 GHz ............... 3,600 670

8 GHz–12 GHz ............. 3,500 1,270

12 GHz–18 GHz ........... 3,500 360

18 GHz–40 GHz ........... 2,100 750

As discussed above, these special

conditions are applicable to Cessna 550

series airplanes, modified by Elliott

Aviation Technical Products

Development, Inc. Should Elliott

Aviation Technical Products

Development, Inc. apply at a later date

for a supplemental type certificate to

modify any other model included on

Type Certificate No. A22CE 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(a)(1).

Conclusion

This action affects only certain

unusual or novel design features on

Cessna 550 series airplanes modified by

Elliott Aviation Technical Products

Development, Inc. of Moline, Illinois. It

is not a rule of general applicability and

affects only the applicant who applied

to the FAA for approval of these features

on modified Cessna 550 series airplanes.

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. 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 immediately.

Therefore, these special conditions are

being made effective upon issuance. The

FAA is requesting comments to allow

interested persons to submit views that

may have not 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. app. 1344, 1348(c),

1352, 1354(a), 1355, 1421 through 1431,

1502, 1651(b)(2), 42 U.S.C. 1857f–10, 4321 et

seq.; E.O. 11514; and 49 U.S.C. 106(g).

The Special Conditions

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the following special

condition is issued as part of the

supplemental type certification basis for

Cessna 550 series airplanes modified by

Elliott Aviation Technical Products

Development, 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

external to the airplane.

2. The following definition applies

with respect to this special condition:

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 February

13, 1995.

Darrell M. Pederson,

Assistant Manager, Transport Airplane

Directorate, Aircraft Certification Service,

ANM–101.

[FR Doc. 95–4772 Filed 2–24–95; 8:45 am]

BILLING CODE 4910–13–M

14 CFR Part 25

[Docket No. NM–103; Special Conditions

No. 25–ANM–94]

Special Conditions: Dassault Aviation

Model Falcon 2000 Airplane; Automatic

Takeoff Thrust Control System

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final special conditions.

SUMMARY: These special conditions are

issued for the Dassault Aviation Model

Falcon 2000 airplane. This new airplane

will have an unusual design feature

associated with an Automatic Takeoff

Thrust Control System (ATTCS), for

which the applicable airworthiness

regulations do not contain appropriate

safety standards for approach climb