Airworthiness Directives; Jetstream Model 4101 Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-40-AD]

Airworthiness Directives; Jetstream Model 4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness

directive (AD) that is applicable to certain Jetstream Model 4101

airplanes. This proposal would require installation of a placard near

the decouple control handle for the elevator control system to ensure

that the pilots are made aware that maintenance action is required to

reset the disconnect unit once the decouple control handle has been

pulled. This proposal is prompted by a report that if the decouple

control handle for the elevator control system is pulled, the lock

linkage will remain unlocked until it is reset during maintenance. The

actions specified by the proposed AD are intended to prevent reduced

controllability of the airplane due to loss of the mechanical linkage

between the pilots' elevator controls, and each pilot having control

authority over only one-half of the elevator control system.

DATES: Comments must be received by July 14, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-103,

Attention: Rules Docket No. 94-NM-40-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 Jetstream Aircraft, Inc., P.O. Box 16029, Dulles

International Airport, Washington, DC 20041-6029. This information may

be examined at the FAA, Transport Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: William Schroeder, Aerospace Engineer,

Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,

1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206)

227-2148; fax (206) 227-1320.

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 94-NM-40-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-103, Attention: Rules

Docket No. 94-NM-40-AD, 1601 Lind Avenue, SW., Renton, Washington

98055-4056.

Discussion

The Civil Aviation Authority (CAA), which is the airworthiness

authority for the United Kingdom, recently notified the FAA that an

unsafe condition may exist on certain Jetstream Model 4101 airplanes.

The CAA advises that if the decouple control handle for the elevator

control system is pulled, the lock linkage will remain unlocked until

it is reset during maintenance. If the lock linkage remains unlocked,

input given by each pilot into the elevator control will not be

mechanically linked. Therefore, each pilot will have only about one-

half the normal elevator control authority when moving the elevator

control. This condition, if not corrected, could result in reduced

controllability of the airplane.

Jetstream has issued Service Bulletin J41-11-004, Revision 1, dated

March 23, 1994, that describes procedures for installation of a placard

on the left forward trim panel of the center console in line with the

decouple control handle for the elevator control system. Installation

of the placard will ensure that the pilots are made aware that

maintenance action is required to reset the disconnect unit once the

decouple control handle for the elevator control system has been

pulled. The CAA classified this service bulletin as mandatory in order

to assure the continued airworthiness of these airplanes in the United

Kingdom.

This airplane model is manufactured in the United Kingdom and is

type certificated for operation in the United States under the

provisions of Sec. 21.29 of the Federal Aviation Regulations and the

applicable bilateral airworthiness agreement. Pursuant to this

bilateral airworthiness agreement, the CAA has kept the FAA informed of

the situation described above. The FAA has examined the findings of the

CAA, 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.

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 installation of a

placard on the left forward trim panel of the center console in line

with the decouple control handle of the elevator. The actions would be

required to be accomplished in accordance with the service bulletin

described previously.

The FAA estimates that 8 airplanes of U.S. registry would be

affected by this proposed AD, that it would take approximately 1 work

hour per airplane to accomplish the proposed actions, and that the

average labor rate is $55 per work hour. Based on these figures, the

total cost impact of the proposed AD on U.S. operators is estimated to

be $440, or $55 per airplane.

The total 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.

The regulations proposed herein would not have substantial direct

effects 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, in

accordance with Executive Order 12612, it is determined that this

proposal would not have sufficient federalism implications to warrant

the preparation of a Federalism Assessment.

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 14

CFR part 39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES-

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.

106(g); and 14 CFR 11.89.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

Jetstream Aircraft Limited: Docket 94-NM-40-AD.

Applicability: Model 4101 airplanes, constructors numbers 41004

through 41024 inclusive, certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

To prevent reduced controllability of the airplane, accomplish

the following:

(a) Within 450 hours time-in-service after the effective date of

this AD, install a placard on the left forward trim panel of the

center console in line with the decouple control handle for the

elevator control system in accordance with Jetstream Service

Bulletin J41-11-004, Revision 1, dated March 23, 1994.

(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, Standardization Branch, ANM-113,

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,

Standardization Branch, ANM-113.

Note: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the Standardization Branch, ANM-113.

(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 May 12, 1994.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-12122 Filed 5-17-94; 8:45 am]

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