33018 Federal Register / Vol. 63, No. 116 /Wednesday, June 17, 1998 / Proposed Rules

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–CE–32–AD]

RIN 2120–AA64

Airworthiness Directives; British

Aerospace Jetstream Model 3101

Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes to

adopt a new airworthiness directive

(AD) that would apply to certain British

Aerospace Jetstream Model 3101

airplanes. The proposed AD would

require replacing the elevator trim servo

motor with a new motor of improved

design and inspecting the cable tension

and electrical operation of the elevator

and trim tab for proper operation and

making any necessary adjustments. The

proposed AD is the result of mandatory

continuing airworthiness information

(MCAI) issued by the airworthiness

authority for the United Kingdom. The

actions specified by the proposed AD

are intended to prevent the elevator trim

servo motor drive gear assembly from

remaining engaged when the autopilot

is disengaged, which could result in the

pilot having to manually overpower the

elevator trim control and possibly lose

directional control of the airplane

during critical phases of flight.

DATES: Comments must be received on

or before July 24, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Central Region,

Office of the Regional Counsel,

Attention: Rules Docket No. 98–CE–32–

AD, Room 1558, 601 E. 12th Street,

Kansas City, Missouri 64106. Comments

may be inspected at this location

between 8 a.m. and 4 p.m., Monday

through Friday, holidays excepted.

Service information that applies to the

proposed AD may be obtained from

British Aerospace Regional Aircraft,

Prestwick International Airport,

Ayrshire, KA9 2RW, Scotland;

telephone: (01292) 479888; facsimile:

(01292) 479703. This information also

may be examined at the Rules Docket at

the address above.

FOR FURTHER INFORMATION CONTACT: Mr.

S.M. Nagarajan, Aerospace Engineer,

FAA, Small Airplane Directorate,

Aircraft Certification Service, 1201

Walnut, suite 900, Kansas City, Missouri

64106; telephone: (816) 426–6932;

facsimile: (816) 426–2169.

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

should 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 that

summarizes 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 No. 98–CE–32–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, Central Region, Office of the

Regional Counsel, Attention: Rules

Docket No. 98–CE–32–AD, Room 1558,

601 E. 12th Street, Kansas City, Missouri

64106.

Discussion

The Civil Airworthiness Authority

(CAA), which is the airworthiness

authority for the United Kingdom,

notified the FAA that an unsafe

condition may exist on certain British

Aerospace Jetstream Model 3101

airplanes that are equipped with an

autopilot. The CAA reports that an

elevator trim servo motor in the

autopilot failed on a Jetstream Model

3101 airplane, causing the pilot to use

extreme force to manually rotate the

elevator trim control handwheel. The

investigation showed that the leaf spring

in the solenoid assembly of the elevator

trim servo motor fractured. This fracture

caused the servo motor drive gear

assembly to remain engaged, even with

the solenoid de-energized and the

autopilot disengaged. This condition

occurs from residual magnetism in the

solenoid core, which keeps the armature

depressed.

These conditions, if not corrected,

could result in loss of directional

control of the airplane during critical

phases of flight.

Relevant Service Information

British Aerospace has issued

Jetstream Service Bulletin 22–A–JA

860413, dated April 16, 1986, which

specifies procedures for replacing the

elevator trim servo motor; and Jetstream

Alert Service Bulletin 22–A–JA 851231,

dated April 9, 1986, which specifies

procedures for inspecting the cable

tension and electrical operation of the

elevator trim, along with testing and

adjusting, if necessary, the friction and

the electric trim manual override loads

after the installation of the new elevator

trim servo motor.

The CAA classified these service

bulletins as mandatory in order to

assure the continued airworthiness of

these airplanes in the United Kingdom.

The CAA classifying a service bulletin

as mandatory is the same in the United

Kingdom as the FAA issuing an AD in

the United States.

The FAA’s Determination

This airplane model is manufactured

in the United Kingdom 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. 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, including the service

information referenced above; and

determined that AD action is necessary

for products of this type design that are

certificated for operation in the United

States.

Explanation of the Provisions of the

Proposed AD

Since an unsafe condition has been

identified that is likely to exist or

develop in other British Aerospace

Jetstream Model 3101 airplanes of the

same type design registered in the

United States, the FAA is proposing AD

action. The proposed AD would require

replacing the elevator trim servo motor

with one of improved design, inspecting

the cable tension and electrical

operation, testing the friction and the
Federal Register / Vol. 63, No. 116 /Wednesday, June 17, 1998 / Proposed Rules 33019

electric trim manual override loads after

the new motor is installed, and making

any necessary adjustments.

Accomplishment of the proposed

modification would be in accordance

with the service bulletins previously

referenced.

Cost Impact

The FAA estimates that 25 airplanes

in the U.S. registry would be affected by

the proposed AD, that it would take

approximately 6 workhours per airplane

to accomplish the proposed action, and

that the average labor rate is

approximately $60 an hour. The

manufacturer will provide parts at no

cost to the owner/operator. Based on

these figures, the total cost impact of the

proposed AD on U.S. operators is

estimated to be $9,000, or $360 per

airplane.

Regulatory Impact

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 action (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) 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 has been placed 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 a new airworthiness directive

(AD) to read as follows:

British Aerospace: Docket No. 98-CE–32-AD.

Applicability: Jetstream Model 3101

airplanes, certificated in any category, with

the following serial numbers, that are

equipped with an autopilot:

Serial Numbers

601 603 604 606 607 609

610 612 614 616 620 621

622 626 629 634 637 641

645 648 649 655 665 686

690

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 (d) 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 within the next 100

hours time-in-service (TIS) after the effective

date of this AD, unless already accomplished.

To prevent the elevator trim servo motor

drive gear assembly from remaining engaged

when the autopilot is disengaged, which

could result in the pilot having to manually

overpower the elevator trim control, and

possibly lose directional control of the

airplane during critical phases of flight,

accomplish the following:

(a) Replace the elevator trim servo motor

with a new elevator trim servo motor of

improved design at fuselage station (F.S.)

421, aft of the rear bulkhead, in accordance

with the ACCOMPLISHMENT

INSTRUCTIONS section in JETSTREAM

Alert Service Bulletin (SB) 22-A-JA 860413,

ORIGINAL ISSUE: April 16, 1986.

(b) Inspect the cable tension, system

friction, and electric trim manual override

and make any necessary adjustments in

accordance with the ACCOMPLISHMENT

INSTRUCTIONS section in JETSTREAM SB

No. 22-A-JA 851231, ORIGINAL ISSUE: April

9, 1986.

(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.

(d) An alternative method of compliance or

adjustment of the compliance time that

provides an equivalent level of safety may be

approved by the Manager, Small Airplane

Directorate, Aircraft Certification Service,

1201 Walnut, suite 900, Kansas City,

Missouri 64106. The request shall be

forwarded through an appropriate FAA

Maintenance Inspector, who may add

comments and then send it to the Manager,

Small Airplane Directorate.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Small Airplane

Directorate.

(e) Questions or technical information

related to British Aerospace Jetstream Service

Bulletin 22-A-JA 851231, dated April 9, 1986,

and Jetstream Alert Service Bulletin 22-A-JA

860413, dated April 16, 1986, should be

directed to British Aerospace Regional

Aircraft, Prestwick International Airport,

Ayrshire, KA9 2RW, Scotland; telephone:

(01292) 479888; facsimile: (01292) 479703.

This service information may be examined at

the FAA, Central Region, Office of the

Regional Counsel, Room 1558, 601 E. 12th

Street, Kansas City, Missouri 64106.

Note 3: The subject of this AD is addressed

in British Aerospace Jetstream Service

Bulletin 22-A-JA 851231, dated April 9, 1986,

and British Aerospace Jetstream Service

Bulletin 22-A-JA 860413, dated April 16,

1998. These service bulletins are classified as

mandatory by the United Kingdom Civil

Aviation Authority (CAA).

Issued in Kansas City, Missouri, on June 9,

1998.

Michael Gallagher,

Manager, Small Airplane Directorate, Aircraft

Certification Service.

[FR Doc. 98–16024 Filed 6–16–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–36–AD]

RIN 2120–AA64

Airworthiness Directives; Lockheed

Model L–1011–385 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

certain Lockheed Model L–1011–385

series airplanes. This proposal would

require the replacement of the flap

position indicator with an improved

flap position indicator. This proposal is

prompted by a report indicating that an

airplane landed at an excessive sink rate

and sustained substantial structural