Federal Register / Vol. 65, No. 15 / Monday, January 24, 2000 / Proposed Rules 3617

Regulatory Guide 1.174, ‘‘An Approach

for Using PRA in Risk-Informed

Decisions on Plant-Specific Changes to

the Licensing Basis,’’ and the NRC’s

Strategic Plan. Consistent with the highlevel at which the guidance described

above has been articulated, specific

factors which need to be addressed in

each case (such as defense in depth and

treatment of uncertainties) would

depend on the particular regulatory

issues involved.

Additional Information

The staff’s proposed high-level

guidelines reflect a measure of

specificity designed to stimulate

reactions, concerns, and views on the

more detailed consideration or

underpinnings of a set of high-level

guidelines. In no way should this

specificity be construed as an indication

that the NRC has established any firm

position regarding these guidelines. The

NRC invites advice and

recommendations from all interested

persons on all aspects of its proposal. In

addition, comments and supporting

reasons are particularly requested in the

following areas:

(1) Clarity and specificity of the

guidelines;

a. Are the proposed guidelines

appropriate and clear?

b. Are there additional guidelines that

would improve clarity and specificity?

c. How does the ‘‘high-level’’ nature

of the guidelines affect the clarity and

specificity of the guidelines?

(2) Implementation of the guidelines;

a. What guidelines, if any, are

mandatory for an activity to qualify as

a performance-based initiative?

b. What is the best way to implement

these guidelines?

c. How should the Backfit Rule apply

to the implementation of performancebased approaches?

d. Should these guidelines be applied

to all types of activity, e.g., should they

be applied to petitions for rulemaking?

e. Should these guidelines only be

applied to new regulatory initiatives?

f. Will these guidelines be effective in

determining whether we can make a

regulatory initiative more performancebased? The staff proposes that these

guidelines be added to our Management

Directives such that whenever the NRC

is involved in a rulemaking, or changing

a regulatory guide or branch technical

position, etc., we will consider the

option of making it more performancebased.

(3) Establishment of objective

performance criteria;

a. In moving to performance-based

requirements, should the current level

of conservatism be maintained or

should introduction of more realism be

attempted?

b. What level of conservatism (safety

margin) needs to be built into a

performance criterion to avoid facing an

immediate safety concern if the criterion

is not met?

c. Recognizing that performance

criteria can be set at different levels in

a hierarchy (e.g., component, train,

system, release, dose), on what basis is

an appropriate level in the hierarchy

selected for setting performance-based

requirements, and what is the

appropriate level of conservatism for

each tier in the hierarchy?

d. Who would be responsible for

proposing and justifying the acceptance

limits and adequacy of objective

criteria?

e. What are examples of performancebased objectives that are not amenable

to risk analyses such as PRA or

Integrated Safety Assessment?

f. In the context of risk-informed

regulation, to what extent should

performance criteria account for

potential risk from beyond-design-basis

accidents (i.e., severe accidents)?

(4) Identification and use of

measurable (or calculable) parameters;

a. How and by whom are performance

parameters to be determined?

b. How do you decide what a relevant

performance parameter is?

c. How much uncertainty can be

tolerated in the measurable or

calculated parameters?

(5) Pilot projects;

a. Would undertaking pilot projects in

the reactor, materials, and waste arenas

provide beneficial experience before

finalizing the guidelines?

b. What should be the relationship

between any such pilot projects and

those being implemented to risk-inform

the regulations?

Dated at Rockville, Maryland, this 14th day

of January, 2000.

For the Nuclear Regulatory Commission.

Charles E. Rossi,

Director Division of Systems Analysis and

Regulatory Effectiveness, Office of Nuclear

Regulatory Research.

[FR Doc. 00–1572 Filed 1–21–00; 8:45 am]

BILLING CODE 7590–01–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–360–AD]

RIN 2120–AA64

Airworthiness Directives; Israel

Aircraft Industries, Ltd., Model 1125

Westwind Astra and Astra SPX Series

Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

adoption of a new airworthiness

directive (AD) that is applicable to all

Israel Aircraft Industries, Ltd., Model

1125 Westwind Astra and Astra SPX

series airplanes. This proposal would

require replacement of the existing

pneumatic de-icing boot pressure

indicator switch with a newly designed

switch. This proposal is prompted by an

occurrence on a similar airplane model

in which the pneumatic de-icing boot

indication light may have provided the

flightcrew with misleading information

as to the proper functioning of the deicing boots. The actions specified by the

proposed AD are intended to prevent ice

accumulation on the airplane leading

edges, which could result in reduced

controllability of the airplane.

DATES: Comments must be received by

February 23, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 99–NM–

360–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00

p.m., Monday through Friday, except

Federal holidays.

Information concerning this proposal

may be examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Norman B. Martenson, Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2110;

fax (425) 227–1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to

participate in the making of the

proposed rule by submitting such

3618 Federal Register / Vol. 65, No. 15 / Monday, January 24, 2000 / Proposed Rules

written data, views, or arguments as

they may desire. Communications shall

identify the Rules Docket number and

be submitted in triplicate to the address

specified above. All communications

received on or before the closing date

for comments, specified above, will be

considered before taking action on the

proposed rule. The proposals contained

in this notice may be changed in light

of the comments received.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the proposed rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report

summarizing each FAA-public contact

concerned with the substance of this

proposal will be filed in the Rules

Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 99–NM–360–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this

NPRM by submitting a request to the

FAA, Transport Airplane Directorate,

ANM–114, Attention: Rules Docket No.

99–NM–360–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

On December 26, 1989, a British

Aerospace Jetstream Model BA–3101

series airplane impacted the ground

approximately 400 feet short of the

runway while executing an instrument

landing system (ILS) approach. The

accident occurred at the Tri-Cities

Airport, Pasco, Washington. The

National Transportation Safety Board

(NTSB) determined that the probable

cause of the accident was the

flightcrew’s decision to continue an

unstabilized ILS approach that led to a

stall, most likely of the horizontal

stabilizer, and loss of control at low

altitude. Contributing to the stall and

loss of control was the accumulation of

ice on the leading edge of the wing and

the horizontal stabilizer, which

degraded the aerodynamic performance

of the airplane.

One result of the NTSB investigation

was the determination that a flight deck

wing de-icing light illuminated at a

lower pressure than the pressure

required to fully inflate the de-icing

boots.

Based on an NTSB Safety

Recommendation, the FAA reviewed

the pneumatic de-icing boot system

designs for airplanes operated under

parts 121 and 135 of the Federal

Aviation Regulations to ensure that the

pneumatic pressure threshold at which

each de-icing boot indication light is

designed to illuminate is sufficient

pressure for effective operation of the

pneumatic de-icing boots. The FAA has

determined that the pneumatic de-icing

boot pressure indicator switch located

on the flight deck of Model 1125

Westwind Astra and Astra SPX series

airplanes may allow the flight deck

indication light to illuminate at a lower

pressure [13 pounds per square inch

gage (psig)] than the pressure required

to fully inflate the de-icing boots (15

psig). This condition, if not corrected,

could result in ice accumulation on the

airplane leading edges, which could

result in reduced controllability of the

airplane.

U.S. Type Certification of the Airplane

This airplane model is manufactured

in Israel and is type certificated for

operation in the United States under the

provisions of section 21.29 of the

Federal Aviation Regulations (14 CFR

21.29) and the applicable bilateral

airworthiness agreement. The FAA has

determined that AD action is necessary

for products of this type design that are

certificated for operation in the United

States.

Explanation of Requirements of

Proposed Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other airplanes of the same

type design registered in the United

States, the proposed AD would require

that the existing pneumatic de-icing

boot pressure indicator switch be

replaced with a switch that activates the

indicator light at 15 psig. The action

would be required to be accomplished

in accordance with a method approved

by the FAA.

Cost Impact

The FAA estimates that 59 airplanes

of U.S. registry would be affected by this

proposed AD. Since the manufacturer

has not yet developed a specific

modification commensurate with the

requirements of this proposal, the FAA

is unable at this time to provide specific

information as to the number of work

hours or cost of parts that would be

required to accomplish the proposed

modification. As indicated earlier in

this preamble, the FAA specifically

invites the submission of comments and

other data regarding the economic

aspect of this proposal.

Regulatory Impact

The regulations proposed herein

would not have a substantial direct

effect on the States, on the relationship

between the national Government and

the States, or on the distribution of

power and responsibilities among the

various levels of government. Therefore,

it is determined that this proposal

would not have federalism implications

under Executive Order 13132.

For the reasons discussed above, I

certify that this proposed regulation (1)

is not a ‘‘significant regulatory action’’

under Executive Order 12866; (2) is not

a ‘‘significant rule’’ under the DOT

Regulatory Policies and Procedures (44

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

promulgated, will not have a significant

economic impact, positive or negative,

on a substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A copy of the draft

regulatory evaluation prepared for this

action is contained in the Rules Docket.

A copy of it may be obtained by

contacting the Rules Docket at the

location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration proposes to amend part

39 of the Federal Aviation Regulations

(14 CFR part 39) as follows:

PART 39—AIRWORTHINESS

DIRECTIVES

1. The authority citation for part 39

continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

Israel Aircraft Industries, LTD.: Docket 99–

NM–360–AD.

Applicability: All Model 1125 Westwind

Astra and Astra SPX series airplanes,

certificated in any category.

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

modified, altered, or repaired in the area

subject to the requirements of this AD. For

airplanes that have been modified, altered, or

repaired so that the performance of the

requirements of this AD is affected, the

owner/operator must request approval for an

Federal Register / Vol. 65, No. 15 / Monday, January 24, 2000 / Proposed Rules 3619

alternative method of compliance in

accordance with paragraph (b) of this AD.

The request should include an assessment of

the effect of the modification, alteration, or

repair on the unsafe condition addressed by

this AD; and, if the unsafe condition has not

been eliminated, the request should include

specific proposed actions to address it.

Compliance: Required as indicated, unless

accomplished previously.

To prevent ice accumulation on the

airplane leading edges, which could result in

reduced controllability of the airplane,

accomplish the following:

Modification

(a) Within 1 year after the effective date of

this AD, replace the pneumatic de-icing boot

pressure indicator switch with a switch that

activates the flight deck indicator light at 15

pounds per square inch gage, in accordance

with a method approved by the Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate.

Alternative Methods of Compliance

(b) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager,

International Branch, ANM–116. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, International Branch,

ANM–116.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the International Branch,

ANM–116.

Special Flight Permits

(c) Special flight permits may be issued in

accordance with sections 21.197 and 21.199

of the Federal Aviation Regulations (14 CFR

21.197 and 21.199) to operate the airplane to

a location where the requirements of this AD

can be accomplished.

Issued in Renton, Washington, on January 18,

2000.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–1598 Filed 1–21–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–13–AD]

RIN 2120–AA64

Airworthiness Directives; Raytheon

Model BAe 125–800A and BAe 125–

800B, Model Hawker 800, and Model

Hawker 800XP Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to certain

Raytheon Model BAe 125–800A, Model

Hawker 800, and Model Hawker 800XP

series airplanes, that currently requires

the filling of two tooling holes on the

firewalls of the left and right engine

pylons with firewall sealant. This action

would require the sealing of all unused

(open) tooling holes on the firewalls of

the left and right engine pylons, and

would expand the applicability to

include additional airplanes. This

proposal is prompted by reports of

additional unused (open) tooling holes,

found at locations other than those

currently addressed. The actions

specified by the proposed AD are

intended to prevent an engine fire from

moving to the fuselage and to the lines

that carry flammable fluid that are

located inboard of the firewall.

DATES: Comments must be received by

February 23, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 99–NM–

13–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Raytheon Aircraft Company, Manager

Service Engineering, Hawker Customer

Support Department, P.O. Box 85,

Wichita, Kansas, 67201–0085. This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington; or at the FAA, Small

Airplane Directorate, Wichita Aircraft

Certification Office, 1801 Airport Road,

Room 100, Mid-Continent Airport,

Wichita, Kansas.

FOR FURTHER INFORMATION CONTACT:

Jeffrey A. Pretz, Aerospace Engineer,

Systems and Propulsion Branch, ACE–

116W, FAA, Small Airplane Directorate,

Wichita Aircraft Certification Office,

1801 Airport Road, Room 100, MidContinent Airport, Wichita, Kansas

67209; telephone (316) 946–4153; fax

(316) 946–4407.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to

participate in the making of the

proposed rule by submitting such

written data, views, or arguments as

they may desire. Communications shall

identify the Rules Docket number and

be submitted in triplicate to the address

specified above. All communications

received on or before the closing date

for comments, specified above, will be

considered before taking action on the

proposed rule. The proposals contained

in this notice may be changed in light

of the comments received.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the proposed rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report

summarizing each FAA-public contact

concerned with the substance of this

proposal will be filed in the Rules

Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 99–NM–13–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this

NPRM by submitting a request to the

FAA, Transport Airplane Directorate,

ANM–114, Attention: Rules Docket No.

99–NM–13–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

On November 22, 1996, the FAA

issued AD 96–24–16, amendment 39–

9840 (61 FR 66878, December 19, 1996),

applicable to certain Raytheon Model

BAe 125–800A, Model Hawker 800, and

Model Hawker 800XP series airplanes,

to require the filling of two tooling holes

on the firewalls of the left and right

engine pylons with firewall sealant.

That action was prompted by

notification from the manufacturer that

these holes were not sealed during

production. The requirements of that

AD are intended to prevent an engine

fire from moving to the fuselage and to

the lines that carry flammable fluid that

are located inboard of the firewall.

Actions Since Issuance of Previous Rule

Since the issuance of that AD, reports

have been received of airplanes with

additional unused tooling holes, at

locations other than those addressed in

AD 96–24–16, on the left and right

engine pylon firewalls, which may

permit the passage of flames to the