Airworthiness Directives; British Aerospace Model ATP Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-16-AD; Amendment 39-8841; AD 94-05-03]

Airworthiness Directives; British Aerospace Model ATP 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 certain British Aerospace Model ATP airplanes. This

action requires inspections to detect damaged main landing gear (MLG)

wheel bearings and replacement of discrepant parts. This amendment is

prompted by reports of failure of the MLG wheel bearings. The actions

specified in this AD are intended to prevent detachment of a MLG wheel

from the airplane.

DATES: Effective March 15, 1994.

The incorporation by reference of certain publications listed in

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

of March 15, 1994.

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

before April 29, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

Attention: Rules Docket No. 94-NM-16-AD, 1601 Lind Avenue, SW., Renton,

Washington 98055-4056.

The service information referenced in this AD 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; 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 (206)

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

SUPPLEMENTARY INFORMATION: 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 British Aerospace

Model ATP airplanes. The CAA advises that reports have been received of

failure of the main landing gear (MLG) wheel bearings on Model ATP

airplanes. Investigations are under way to determine the cause of these

failures. This condition, if not corrected, could result in detachment

of a MLG wheel from the airplane.

Jetstream has issued Service Bulletin ATP-32-48, Revision 1, dated

January 28, 1994, that describes procedures for performing daily and

pre-flight detailed visual inspections to detect damage or

discoloration of the main wheel hub caps and of the outer side of the

inflation valve side hubs on the MLG wheels. (This service bulletin

references Dunlop Service Bulletin AHA 1663-32-1088, Revision 1, dated

January 13, 1994, as the appropriate source of service information.)

The CAA classified this service bulletin as mandatory and issued CAA

Airworthiness Directive 007-12-93, dated December 22, 1993, 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 (FAR) (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.

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 failure of the

MLG wheel bearings, which could result in detachment of the MLG wheel

from the airplane. This AD requires daily and pre-flight detailed

visual inspections to detect damage or discoloration of the main wheel

hub caps and of the outer side of the inflation valve side hubs on the

MLG wheels. The actions are required to be accomplished in accordance

with the Jetstream service bulletin described previously.

This AD also requires replacement of the entire MLG wheel assembly

and bearings with a serviceable wheel assembly and bearings, if any

damage or discoloration is detected during any inspection. The

replacement is required to be accomplished in accordance with the

airplane maintenance manual.

Operators should note that, although Jetstream Service Bulletin

ATP-32-48, Revision 1, dated January 28, 1994, specifies that certain

pilots may perform both the daily and pre-flight inspections, it is the

FAA's determination that both inspections must be performed by

appropriately certificated maintenance personnel, as specified in

Sec. 43.3 of the FAR (14 CFR 43.3).

This is considered to be interim action until final action is

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

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 notice must submit a self-addressed,

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

to Docket Number 94-NM-16-AD.'' The postcard will be date stamped and

returned to the commenter.

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 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 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:

94-05-03 British Aerospace (Commercial Aircraft), Limited:

Amendment 39-8841. Docket 94-NM-16-AD.

Applicability: Model ATP series airplanes; constructor's numbers

2001 through 2063 inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

To prevent failure of the main landing gear (MLG) wheel

bearings, which could result in detachment of a MLG wheel from the

airplane, accomplish the following:

(a) Within 24 hours after the effective date of this AD, perform

cleaning and a detailed visual inspection to detect damage or

discoloration of the wheel hub caps and of the outer side of the

inflation valve side hubs on the MLG wheels, in accordance with

paragraph 2.A.(1) of the Accomplishment Instructions of Jetstream

Service Bulletin ATP-32-48, Revision 1, dated January 28, 1994.

Thereafter, prior to the first flight of each day, repeat this

cleaning and inspection. The cleaning and inspection must be

performed by appropriately certificated maintenance personnel as

specified in Sec. 43.3 of the Federal Aviation Regulations (FAR). If

any damage or discoloration is found during any inspection required

by this paragraph, prior to further flight, replace the existing MLG

wheel assembly and bearings with a serviceable wheel assembly and

bearings in accordance with the airplane maintenance manual. -

(b) Following accomplishment of the initial inspection required

by paragraph (a) of this AD, prior to each flight, with the

exception of the first flight of each day, perform a pre-flight

detailed visual inspection to detect damage or heat discoloration of

the wheel hub cap and the outer side of each inflation valve side

hub on the MLG wheels, in accordance with paragraph 2.A.(2) of the

Accomplishment Instructions in Jetstream Service Bulletin ATP-32-48,

Revision 1, dated January 28, 1994. The pre-flight inspections must

be performed by appropriately certificated maintenance personnel, as

specified in Sec. 43.3 of the FAR. If any damage or discoloration is

found during any inspection required by this paragraph, prior to

further flight, replace the existing MLG wheel assembly and bearings

with a serviceable wheel assembly and bearings in accordance with

the airplane maintenance manual.

(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,

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.

(d) Special flight permits may be issued in accordance with

Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the

airplane to a location where the requirements of this AD can be

accomplished.

(e) The cleaning and inspections shall be done in accordance

with Jetstream Service Bulletin ATP-32-48, Revision 1, dated January

28, 1994. 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 Jetstream Aircraft,

Inc., P.O. Box 16029, Dulles International Airport, Washington, DC

20041-6029. 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 March 15, 1994.

Issued in Renton, Washington, on February 18, 1994.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-4275 Filed 2-24-94; 8:45 am]

BILLING CODE 4910-13-U