Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-339-AD]

RIN 2120-AA64

Airworthiness Directives; British Aerospace (Jetstream) Model

4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing

airworthiness directive (AD), applicable to all British Aerospace

(Jetstream) Model 4101 airplanes, that currently requires repetitive

functional testing of the main entrance door, cleaning and lubricating

of the ``speed'' lock and ``G'' lock systems, and repair, if necessary.

This action would add a requirement for replacement of the ``G'' lock

rollers with new, improved ``G'' lock rollers. 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 inability of the main entrance

door to open, which could delay or impede passengers exiting the

airplane, or rescue personnel from entering the airplane during an

emergency.

DATES: Comments must be received by August 31, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-114,

Attention: Rules Docket No. 97-NM-339-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 AI(R) American Support, Inc., 13850 Mclearen Road,

Herndon, Virginia 20171. 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 97-NM-339-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. 97-NM-339-AD, 1601 Lind Avenue, SW., Renton, Washington

98055-4056.

Discussion

On September 3, 1997, the FAA issued AD 97-19-02, amendment 39-

10122 (62 FR 47362, September 9, 1997), applicable to all British

Aerospace (Jetstream) Model 4101 airplanes, to require repetitive

functional testing of the main entrance door, cleaning and lubricating

of the ``speed'' lock and ``G'' lock systems, and repair, if necessary.

That action was prompted by reports of flightcrews and ground crews

being unable to open the main entrance door. The requirements of that

AD are intended to prevent inability of the main entrance door to open,

which could delay or impede passengers exiting the airplane, or rescue

personnel from entering the airplane during an emergency.

Actions Since Issuance of Previous Rule

In the preamble to AD 97-19-02, the FAA specified that the actions

required by that AD were considered ``interim action'' and that once a

modification is developed, approved, and available, the FAA may

consider additional rulemaking action. The manufacturer now has

developed such a modification, and the FAA has determined that further

rulemaking action is indeed necessary; this proposed AD follows from

that determination.

Explanation of Relevant Service Information

British Aerospace Regional Aircraft has issued Jetstream Alert

Service Bulletins J41-A-52-059, dated September 12, 1997, and Revision

2, dated January 23, 1998, which describe procedures for replacement of

the ``G'' lock rollers with rollers having increased diameters. The

installation of ``G'' lock rollers with increased diameters provides a

means to prevent jamming of the main entrance door by increasing the

mechanism clearance when the door handle is operated. The Civil

Aviation Authority (CAA), which is the airworthiness authority for the

United Kingdom, classified these alert service bulletins as mandatory

and issued British airworthiness directive 001-09-97 in order to assure

the continued airworthiness of these airplanes in the United Kingdom.

FAA's Conclusions

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, and determined

that AD action is necessary for products of this type design that are

certificated for operation in the United States.

[[Page 40857]]

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 supersede AD 97-19-02 to

continue to require repetitive functional testing of the main entrance

door, cleaning and lubricating of the ``speed'' lock and ``G'' lock

systems, and repair, if necessary. The proposed AD would add a

requirement for replacement of the ``G'' lock rollers with new,

improved ``G'' lock rollers. The actions would be required to be

accomplished in accordance with the alert service bulletins described

previously.

Cost Impact

There are approximately 57 airplanes of U.S. registry that would be

affected by this proposed AD.

The actions that are currently required by AD 97-19-02 take

approximately 1 work hour per airplane to accomplish, at an average

labor rate of $60 per work hour. Based on these figures, the cost

impact of the currently required actions on U.S. operators is estimated

to be $3,420, or $60 per airplane, per functional test cycle.

The new actions that are proposed in this AD action would take

approximately 3 work hours per airplane to accomplish, at an average

labor rate of $60 per work hour. Required parts would be provided by

the manufacturer at no cost to the operator. Based on these figures,

the cost impact of the proposed requirements of this AD on U.S.

operators is estimated to be $10,260, or $180 per airplane.

The cost impact figures discussed above are based on assumptions

that no operator has yet accomplished any of the current or 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 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

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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by removing amendment 39-10122 (62 FR

47362, September 9, 1997), and by adding a new airworthiness directive

(AD), to read as follows:

British Aerospace Regional Aircraft [Formerly Jetstream Aircraft

Limited; British Aerospace (Commercial Aircraft) Limited]: Docket

97-NM-339-AD. Supersedes AD 97-19-02, Amendment 39-10122.

Applicability: All Jetstream Model 4101 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 (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 as indicated, unless accomplished

previously.

To prevent inability of the main entrance door to open, which

could delay or impede passengers exiting the airplane, or rescue

personnel from entering the airplane during an emergency, accomplish

the following:

Restatement of Requirements of AD 97-19-02, Amendment 39-10122:

(a) Within 30 days after September 24, 1997 (the effective date

of AD 97-19-02, amendment 39-10122), perform a functional test to

verify proper operation of the main entrance door (including the

``G'' lock system) and the ``speed'' lock system of the main

entrance door, in accordance with Section 52-10-05 of BAe Jetstream

Series 4101 Maintenance Manual (MM).

(1) If the ``speed'' lock and the ``G'' lock function

satisfactorily: Within 60 days after September 24, 1997, perform the

actions specified in paragraphs (a)(1)(i) and (a)(1)(ii) of this AD.

(i) Clean (remove existing contaminants and lubricant) and re-

lubricate (with a dry lubricant) the ``speed'' lock and main

entrance door ``G'' lock systems in accordance with Jetstream

Service Bulletin J41-52-058, dated July 14, 1997. And,

(ii) Following accomplishment of paragraph (a)(1)(i) of this AD,

and prior to further flight, repeat the functional test specified in

paragraph (a) of this AD.

(A) If the ``G'' lock and the ``speed'' lock function

satisfactorily in the functional test required by paragraph

(a)(1)(ii) of this AD, accomplish the requirements of paragraph (b)

of this AD.

(B) If the ``G'' lock and the ``speed'' lock do not function

satisfactorily in the functional test required by paragraph

(a)(1)(ii) of this AD: Prior to further flight, repair the ``G''

lock and the ``speed'' lock in accordance with a method approved by

the Manager, International Branch, ANM-116, FAA, Transport Airplane

Directorate.

(2) If either the ``speed'' lock and/or the ``G'' lock do not

function correctly: Prior to further flight, perform the actions

specified in paragraphs (a)(2)(i) and (a)(2)(ii) of this AD.

(i) Clean (remove existing contaminants and lubricant) and re-

lubricate (with a dry lubricant) the main entrance door ``speed''

lock and ``G'' lock systems in accordance with Jetstream Service

Bulletin J41-52-058, dated July 14, 1997. And,

(ii) Following accomplishment of paragraph (a)(2)(i) of this AD,

and prior to further flight, repeat the functional test of the main

entrance door (including the ``G'' lock system) and the ``speed''

lock system, in accordance with the MM.

(A) If the ``G'' lock and ``speed'' lock function satisfactorily

in the functional test required by paragraph (a)(2) of this AD,

accomplish the requirements of paragraph (b) of this AD.

(B) If the ``G'' lock and ``speed'' lock do not function

satisfactorily in the functional tests required by paragraph (a)(2)

of this AD: Prior to further flight, repair the ``G'' lock and

``speed'' lock in accordance with a method approved by the Manager,

International Branch, ANM-116.

(b) Perform the actions specified in paragraphs (b)(1) and

(b)(2) of this AD within 1,500 hours time-in-service following

accomplishment of the initial functional test

[[Page 40858]]

of the main entrance door required by paragraph (a) of this AD.

Repeat the actions specified in paragraphs (b)(1) and (b)(2) of this

AD, thereafter, at intervals not to exceed 1,500 hours time-in-

service.

(1) Clean (remove contaminants and dry lubricant) and re-

lubricate (with dry lubricant) the main entrance door ``speed'' lock

and ``G'' lock systems in accordance with Jetstream Service Bulletin

J41-52-058, dated July 14, 1997.

(2) Following accomplishment of paragraph (b)(1) of this AD and

prior to further flight, perform a functional test of the main

entrance door (including the ``G'' lock system) and the ``speed''

lock system, in accordance with the MM. If the ``G'' lock or

``speed'' lock system do not perform satisfactorily: Prior to

further flight, repair the ``G'' lock or ``speed'' lock system in

accordance with a method approved by the Manager, International

Branch, ANM-116.

New Requirements of This AD:

(c) Within 60 days after the effective date of this AD, replace

the ``G'' lock rollers on the main entrance door with new, improved

``G'' lock rollers in accordance with Jetstream Alert Service

Bulletin J41-A-52-059, dated September 12, 1997, or Revision 2,

dated January 23, 1998.

(d) 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.

(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 British

airworthiness directive 001-09-97.

Issued in Renton, Washington, on July 24, 1998.

S. R. Miller,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 98-20430 Filed 7-30-98; 8:45 am]

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