Airworthiness Directives; British Aerospace Model BAe 146 and BAe Avro 146-RJ Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-70-AD]

RIN 2120-AA64

Airworthiness Directives; British Aerospace Model BAe 146 and BAe

Avro 146-RJ Series 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 British Aerospace Model

BAe 146 and BAe Avro 146-RJ series airplanes. This proposal would

require repetitive inspections to detect signs of chafing to the fuel

feed pipe, and repair or replacement of the fuel feed pipe with a

serviceable part, if necessary; and ensuring that responder units,

electrical connector backshells, and associated wiring are undamaged

and are positioned correctly to provide maximum clearance with the fuel

pipe. 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 damage

to the fuel feed pipe, which could result in fuel leaks and an

increased potential for fire on the airplane.

DATES: Comments must be received by September 13, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

Attention: Rules Docket No. 99-NM-70-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

[[Page 43956]]

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 99-NM-70-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. 99-NM-70-AD, 1601 Lind Avenue, SW., Renton, Washington

98055-4056.

Discussion

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

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

condition may exist on certain British Aerospace Model BAe 146 and BAe

Avro 146-RJ series airplanes. The CAA advises that it has received

service reports of damage to the fuel feed pipe that supplies secondary

fuel flow from the fuel flow divider to the right side fuel manifold.

The CAA attributes the damage to movement of the firewall responder

unit within its restraining clamps, leading to contact between the

backshell clamps of the responder connector and the adjacent fuel pipe.

This condition, if not corrected, could result in damage to the fuel

feed pipe, which could result in fuel leaks and an increased potential

for fire on the airplane.

Explanation of Relevant Service Information

British Aerospace has issued Service Bulletin SB.26-44, dated

February 25, 1999, which describes procedures for repetitive detailed

inspections to detect signs of chafing of the fuel feed pipe, and

repair or replacement of the fuel feed pipe with a serviceable part, if

necessary; and procedures for ensuring that responder units, electrical

backshell connectors, and associated wiring are undamaged and are

positioned correctly to provide maximum clearance with the fuel pipe.

Accomplishment of the actions specified in the service bulletin is

intended to adequately address the identified unsafe condition. The CAA

classified this service bulletin as mandatory and issued British

airworthiness directive 009-02-99 in order to assure the continued

airworthiness of these airplanes in the United Kingdom.

British Aerospace has also issued Service Bulletin SB.26-44-01638A,

dated February 25, 1999, which describes procedures for modifying the

airplane to improve the responder unit clamping arrangement to prevent

chafing against the fuel pipe. This modification would eliminate the

need for the repetitive inspections.

FAA's Conclusions

These airplane models are manufactured in the United Kingdom and

are 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.

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 require accomplishment of

the actions specified in the service bulletin described previously.

This proposed AD also would provide for optional terminating action for

the repetitive inspections.

Operators should note that, in consonance with the findings of the

CAA, the FAA has determined that the repetitive inspections proposed by

this AD can be allowed to continue in lieu of accomplishment of a

terminating action. In making this determination, the FAA considers

that, in this case, long-term continued operational safety will be

adequately assured by accomplishing the repetitive inspections to

detect signs of chafing of the fuel feed pipes before it represents a

hazard to the airplane.

Cost Impact

The FAA estimates that 20 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 $60 per work hour. Based on these figures, the

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

$1200, or $60 per airplane, per inspection cycle.

The 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.

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.

[[Page 43957]]

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 adding the following new

airworthiness directive:

British Aerospace Regional Aircraft (Formerly British Aerospace

Regional Aircraft Limited, Avro International Aerospace Division;

British Aerospace, PLC; British Aerospace Commercial Aircraft

Limited): Docket 99-NM-70-AD.

Applicability: Model BAe 146 and Avro 146-RJ series airplanes,

except those on which Modification HCMO1638A (British Aerospace

Service Bulletin SB.26-44-01638A, dated February 25, 1999) has been

accomplished; certificated in any category.

Note 1: This AD applies to each airplane identified in the

preceding applicability provision, regardless of whether it has been

otherwise 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 damage to the fuel feed pipe, which could result in

fuel leaks and an increased potential for fire on the airplane,

accomplish the following:

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

a detailed visual inspection of the fuel feed pipe for signs of

chafing, and ensure that responder units are undamaged and

positioned correctly in relation to clamps and that electrical

connector backshells and associated wiring are undamaged and are

oriented to provide maximum clearance with the fuel pipe; in

accordance with British Aerospace Service Bulletin SB.26-44, dated

February 25, 1999.

(1) If no chafing is detected, repeat the inspection thereafter

at intervals not to exceed 3,000 flight hours, until accomplishment

of paragraph (b) of this AD.

(2) If any sign of chafing is detected, prior to further flight,

accomplish paragraph (a)(2)(i) or (a)(2)(ii) of this AD, as

applicable, in accordance with British Aerospace Service Bulletin

SB.26-44, dated February 25, 1999. Repeat the inspection thereafter

at intervals not to exceed 3,000 flight hours, until accomplishment

of paragraph (b) of this AD.

(i) If the damage does not exceed one-half the thickness of the

fuel feed pipe wall, prior to further flight, repair the pipe.

(ii) If the damage exceeds one-half the thickness of the fuel

feed pipe wall, prior to further flight, replace the pipe with a

serviceable part.

Note 2: For the purposes of this AD, a detailed inspection is

defined as: ``An intensive visual examination of a specific

structural area, system, installation, or assembly to detect damage,

failure, or irregularity. Available lighting is normally

supplemented with a direct source of good lighting at intensity

deemed appropriate by the inspector. Inspection aids such as mirror,

magnifying lenses, etc., may be used. Surface cleaning and elaborate

access procedures may be required.''

(b) Modification of the clamping arrangement for the firewall

responder units in accordance with British Aerospace Service

Bulletin SB.26-44-01638A, dated February 25, 1999, constitutes

terminating action for the requirements of this AD.

Alternative Methods of Compliance

(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, International Branch, ANM-116, 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, International

Branch, ANM-116, FAA, Transport Airplane Directorate.

Note 3: Information concerning the existence of approved

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

obtained from the International Branch, ANM-116.

Special Flight Permits

(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.

Note 4: The subject of this AD is addressed in British

airworthiness directive 009-02-99.

Issued in Renton, Washington, on August 6, 1999.

D. L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 99-20894 Filed 8-11-99; 8:45 am]

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