Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-164-AD; Amendment 39-10122; AD 97-19-02]

RIN 2120-AA64

Airworthiness Directives; British Aerospace (Jetstream) Model

4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that

is applicable to all British Aerospace (Jetstream) Model 4101

airplanes. This action 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 amendment is

prompted by reports of flight crews and ground crews being unable to

open the main entrance door. The actions specified in this 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: Effective September 24, 1997.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of September 24, 1997.

Comments for inclusion in the Rules Docket must be received on or

before October 9, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

Attention: Rules Docket No. 97-NM-164-AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055-4056.

The service information referenced in this AD 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; or at the

Office of the Federal Register, 800 North Capitol Street, NW., suite

700, Washington, DC.

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 (425)

227-2148; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: The FAA has received several reports

indicating that flight crews and/or ground crews were unable to open

the main entrance door from either the inside or outside of British

Aerospace (Jetstream) Model 4101 airplanes. Investigation revealed

excessive friction in the main entrance door ``speed'' lock and ``G''

lock systems due to impurities (dirt) at mechanical linkage points of

movement in these locking systems. Additionally, excessive friction in

the ``speed'' lock and ``G'' lock systems has been attributed to the

use of a certain type of lubricant currently specified by the airplane

manufacturer. Such excessive friction, if not corrected, could result

in the main entrance door being ``stuck,'' and consequently, unable to

be opened from the inside or the outside of the airplane. The FAA has

reviewed the available information and has determined that the

inability to open the main entrance door during an emergency may cause

delay or impede passengers exiting the airplane, or rescue personnel

from entering the airplane during an emergency.

Explanation of Relevant Service Information

Jetstream has issued Service Bulletin J41-52-058, dated July 14,

1997, which describes procedures for performing repetitive functional

checks of the main entrance door, and cleaning and lubricating of

``speed'' lock and ``G'' lock systems.

Accomplishment of these actions will ensure that the ``speed'' lock

and ``G'' lock systems will not prevent the main entrance door from

being opened when the airplane is on the ground.

U.S. Type Certification of the Airplane

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.

Explanation of Requirements of 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, this AD is being issued to prevent excessive

friction in the main entrance door ``speed'' lock and ``G'' lock

systems, which could prohibit the door from being opened, and

consequently delay or impede passengers when exiting the airplane, or

rescue personnel from entering the airplane during an emergency. This

AD

[[Page 47363]]

requires initial functional testing of the main entrance door and

``speed'' lock system, cleaning, and lubrication of the ``speed'' lock

and ``G'' lock systems of the main entrance door, and repair, if

necessary. This AD also requires follow-on repetitive cleaning,

lubrication, and functional testing of the ``speed'' lock and ``G''

lock systems of the main entrance door. The initial functional test of

the main entrance door is required to be accomplished in accordance

with the Jetstream Model 4101 Airplane Maintenance Manual. Other

actions are required to be accomplished in accordance with the service

bulletin described previously.

Interim Action

This action is considered to be interim action until final action

is identified, at which time the FAA may consider further rulemaking.

Determination of Rule's Effective Date

Since a situation exists that requires the immediate adoption of

this regulation, it is found that notice and opportunity for prior

public comment hereon are impracticable, and that good cause exists for

making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves

requirements affecting flight safety and, thus, was not preceded by

notice and an opportunity for public comment, comments are invited on

this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All

communications received on or before the closing date for comments will

be considered, and this rule may be amended in light of the comments

received. Factual information that supports the commenter's ideas and

suggestions is extremely helpful in evaluating the effectiveness of the

AD action and determining whether additional rulemaking action would be

needed.

Comments are specifically invited on the overall regulatory,

economic, environmental, and energy aspects of the rule that might

suggest a need to modify the 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

AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments

submitted in response to this rule must submit a self-addressed,

stamped postcard on which the following statement is made: ``Comments

to Docket Number 97-NM-164-AD.'' The postcard will be date stamped and

returned to the commenter.

Regulatory Impact

The regulations adopted herein will 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 final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency

regulation that must be issued immediately to correct an unsafe

condition in aircraft, and that it is not a ``significant regulatory

action'' under Executive Order 12866. It has been determined further

that this action involves an emergency regulation under DOT Regulatory

Policies and Procedures (44 FR 11034, February 26, 1979). If it is

determined that this emergency regulation otherwise would be

significant under DOT Regulatory Policies and Procedures, a final

regulatory evaluation will be prepared and placed in the Rules Docket.

A copy of it, if filed, may be obtained from the Rules Docket at the

location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by

reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the

Administrator, the Federal Aviation Administration amends 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 adding the following new

airworthiness directive:

97-19-02 British Aerospace Regional Aircraft [Formerly Jetstream

Aircraft Limited, British Aerospace (Commercial Aircraft) Limited]:

Amendment 39-10122. Docket 97-NM-164-AD.

Applicability: All Model Jetstream 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 (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 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:

(a) Within 30 days after the effective date of this AD, 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 the effective date of the AD,

perform the actions specified in paragraphs (a)(1)(i) and (a)(1)(ii)

of this AD.

(i) Clean (remove existing contaminents 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, Standardization Branch, ANM-113, 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

[[Page 47364]]

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

(i) Clean (remove existing contaminents 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,

Standardization Branch, ANM-113.

(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 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 contaminents 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, Standardization

Branch, ANM-113.

(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, Standardization Branch, ANM-113.

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 2: Information concerning the existence of approved

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

obtained from the Standardization Branch, ANM-113.

(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.

(e) Certain actions shall be done in accordance with Jetstream

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

by reference was approved by the Director of the Federal Register in

accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be

obtained from AI(R) American Support, Inc., 13850 Mclearen Road,

Herndon, Virginia 20171. Copies may be inspected at the FAA,

Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,

Washington; or at the Office of the Federal Register, 800 North

Capitol Street, NW., suite 700, Washington, DC.

(f) This amendment becomes effective on September 24, 1997.

Issued in Renton, Washington, on September 3, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 97-23861 Filed 9-8-97; 8:45 am]

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