Federal Register / Vol. 65, No. 3 / Wednesday, January 5, 2000 / Proposed Rules 399

provides an acceptable level of safety may be

used if approved by the Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate. 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

(e) 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.

Note 3: The subject of this AD is addressed

in French airworthiness directive 1999–013–

276(B), dated January 13, 1999.

Issued in Renton, Washington, on

December 29, 1999.

D.L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–137 Filed 1–4–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–261–AD]

RIN 2120–AA64

Airworthiness Directives;

Construcciones Aeronauticas, S.A.

(CASA) Model CN–235–100 and CN–

235–200 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

CASA Model CN–235–100 and CN–

235–200 series airplanes. This proposal

would require replacement of existing

anti-icing distributor valves with new,

improved valves. This proposal is

prompted by issuance of mandatory

continuing airworthiness information by

a foreign civil airworthiness authority.

The actions specified by the proposed

AD are intended to prevent ice

accumulation on the wings or tail of the

airplane, which could result in reduced

controllability of the airplane.

DATES: Comments must be received by

February 4, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 99–NM–

261–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9 a.m. and 3 p.m.,

Monday through Friday, except Federal

holidays.

The service information referenced in

the proposed rule may be obtained from

Construcciones Aeronauticas, S.A.,

Getafe, Madrid, Spain. This information

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

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–261–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–261–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

leading edge ice, which degraded the

aerodynamic performance of the

airplane.

One result of the NTSB investigation

was the determination that the flight

deck wing de-icing light illuminated at

a lower pressure than the pressure

required to fully inflate the de-icing

boots. The premature illumination of

the wing de-icing light was due to a

failure within the wing de-icing boot

system, which allowed sufficient air

pressure to give the appearance of

normal operation based on the de-icing

light, without actually inflating the

boots sufficiently to remove ice.

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 existing design of

the flight deck pneumatic de-icing boot

pressure indicator switch on CASA

Model CN–235–100 and CN–235–200

series airplanes may allow the flight

deck indicator light to illuminate at a

lower pressure than the pressure

required to fully inflate the de-icing

boots [15 pounds per square inch gage

(psig)]. Illumination of the light at a

lower pressure would indicate to the

flightcrew that the pneumatic ice boots

are operating normally, though the boots

may not be sufficiently inflated to shed

ice. This condition, if not corrected,

could result in ice accumulation on the

wings or tail of the airplane, which

could result in reduced controllability

of the airplane.

400 Federal Register / Vol. 65, No. 3 / Wednesday, January 5, 2000 / Proposed Rules

Explanation of Relevant Service

Information

CASA has issued Service Bulletin SB–

235–30–14, dated August 13, 1999,

which describes procedures for

replacement of existing anti-icing

distributor valves in the wing and tail

areas of the airplane with new,

improved valves. The new, improved

valves increase the weak pressure of the

anti-icing distributor valves pressure

sensor to 15.5 psig (±0/5 psig).

Accomplishment of the actions

specified in the service bulletin is

intended to adequately address the

identified unsafe condition. The

Direccio ́n General de Aviacio ́n Civil

(DGAC), which is the airworthiness

authority for Spain, classified this

service bulletin as mandatory and

issued Spanish airworthiness directive

04/99, dated July 30, 1999, in order to

assure the continued airworthiness of

these airplanes in Spain.

FAA’s Conclusions

These airplane models are

manufactured in Spain and are 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. Pursuant to this bilateral

airworthiness agreement, the DGAC has

kept the FAA informed of the situation

described above. The FAA has

examined the findings of the DGAC,

reviewed all available information, and

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

accomplishment of the actions specified

in the service bulletin described

previously.

Cost Impact

The FAA estimates that 2 airplanes of

U.S. registry would be affected by this

proposed AD, that it would take

approximately 30 work hours per

airplane to accomplish the proposed

replacement, and that the average labor

rate is $60 per work hour. Required

parts would cost approximately $4,671

per airplane. Based on these figures, the

cost impact of the proposed AD on U.S.

operators is estimated to be $12,942, or

$6,471 per airplane.

The cost impact figure discussed

above is based on assumptions that no

operator has yet accomplished any of

the proposed requirements of this AD

action, and that no operator would

accomplish those actions in the future if

this AD were not adopted.

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:

Construcciones Aeronauticas, S.A. (CASA):

Docket 99–NM–261–AD.

Applicability: All Model CN–235–100 and

CN–235–200 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

alternative method of compliance in

accordance with paragraph (c) 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 wings

or tail of the airplane, which could result in

reduced controllability of the airplane,

accomplish the following:

Replacement

(a) Within 4 months after the effective date

of this AD, replace the existing anti-icing

distributor valves, having part number (P/N)

AC960013, in the wing and tail areas of the

airplane, with new, improved valves, having

P/N AC911016, in accordance with CASA

Service Bulletin SB–235–30–14, dated

August 13, 1999.

(b) As of the effective date of this AD, no

person shall install a distributor valve having

P/N AC960013 on any airplane.

Alternative Methods of Compliance

(c) 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, FAA,

Transport Airplane Directorate. 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

(d) 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.

Note 3: The subject of this AD is addressed

in Spanish airworthiness directive 04/99,

dated July 30, 1999.

Issued in Renton, Washington, on

December 29, 1999.

D.L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–136 Filed 1–4–00; 8:45 am]

BILLING CODE 4910–13–U