Federal Register / Vol. 66, No. 80 / Wednesday, April 25, 2001 / Proposed Rules 20763

standards and procedures used must be

acceptable to the Administrator in

accordance with FAR Section 43.13.

(1) Accomplish corrosion tasks C–55–320–

05 and C–55–330–05, per Revision D of the

Document. Thereafter, accomplish these

corrosion tasks at intervals not to exceed 5

years.

(2) Accomplish corrosion task C–57–540–

02, per Revision D of the Document.

Thereafter, accomplish this corrosion task at

intervals not to exceed 5 years.

(3) Accomplish corrosion task C–57–530–

04, per Revision D of the Document.

Thereafter, accomplish this corrosion task at

intervals not to exceed 5 years.

(4) Accomplish corrosion task C–53–310–

03, per Revision D of the Document.

Thereafter, accomplish this corrosion task at

intervals not to exceed 10 years.

Inspection of the Horizontal Stabilizer

(d) Within 15 years time-in-service or 5

years after the effective date of this AD,

whichever occurs later: Conduct a free-play

inspection of the horizontal stabilizer pivot

bearing, disassemble ALL horizontal

stabilizer pivot bearing assemblies, and

perform a detailed visual inspection of the

pivot bearing assembly components to detect

corrosion, in accordance with the procedures

specified in Task C–55–350–01 of Revision D

of the Document. Thereafter, repeat this

inspection at intervals not to exceed 5 years.

Note 12: This paragraph does not require

inspection of any area that has not exceeded

the IA for that area.

Note 13: For the purposes of this AD, a

detailed visual 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.’’

Acceptable Alternative Compliance With

Certain Requirements

(e) As an alternative to the requirements of

paragraph (c) and (d) of this AD: Within 90

days after the effective date of this AD, revise

the FAA-approved maintenance program to

incorporate and implement Revision D of

Lockheed Document Number LR 31889,

‘‘Corrosion and Protection Control Program,

TriStar L–1011’’, dated August 15, 1999.

Accommodating Scheduling Requirements

(f) To accommodate unanticipated

scheduling requirements of paragraph (c) or

(d) of this AD, it is acceptable for an R

interval to be increased by up to 10%, but not

to exceed 6 months. The FAA must be

informed, in writing, of any such extension

within 30 days after such adjustment of the

schedule.

(g)(1) If, during any inspection conducted

in accordance with this AD, Level 3

corrosion is determined to exist in any

airplane area, accomplish the actions

specified in either paragraph (g)(1)(i) or

(g)(1)(ii) of this AD within 7 days after such

determination. Information collection

requirements contained in this regulation

have been approved by the Office of

Management and Budget (OMB) under the

provisions of the Paperwork Reduction Act of

1980 (44 U.S.C. 3501 et seq.) and have been

assigned OMB Control Number 2120–0056.

(i) Submit a report of that determination to

the FAA and complete the corrosion task in

the affected areas on all Model L–1011 series

airplanes in the operator’s fleet; or

(ii) Submit to the FAA for approval one of

the following:

(A) A proposed schedule for performing

the corrosion tasks in the affected areas on

the remaining Model L–1011 series airplanes

in the operator’s fleet, which is adequate to

ensure that any other Level 3 corrosion is

detected in a timely manner, along with

substantiating data for that schedule; or

(B) Data substantiating that the Level 3

corrosion found is an isolated occurrence.

Note 14: Notwithstanding the provisions of

Section 1 of the Document, which would

permit corrosion that otherwise meets the

definition of Level 3 corrosion (i.e., which is

determined to be a potentially urgent

airworthiness concern requiring expeditious

action) to be treated as Level 1 if the operator

finds that it ‘‘can be attributed to an event not

typical of the operator’s usage of other

airplanes in the same fleet,’’ this paragraph

requires that data substantiating any such

finding be submitted to the FAA for

approval.

(2) The FAA may impose schedules other

than those proposed, upon finding that such

changes are necessary to ensure that any

other Level 3 corrosion is detected in a

timely manner.

(3) Within the time schedule approved

under paragraph (g)(1) or (g)(2) of this AD,

accomplish the corrosion tasks in the affected

areas of the remaining Model L–1011 series

airplanes in the operators’ fleet.

(h) If, as a result of any inspection after an

initial inspection conducted in accordance

with the requirements of this AD, it is

determined that corrosion findings exceed

Level 1 in any area, within 60 days after such

determination, implement a means, approved

by the FAA, to reduce future findings of

corrosion in that area to Level 1 or better.

(i) Before any operator places into service

any airplane subject to the requirements of

this AD, a schedule for the accomplishment

of corrosion tasks required by this AD must

be established in accordance with paragraph

(i)(1) or (i)(2) of this AD, as applicable:

(1) For airplanes previously maintained in

accordance with this AD, the first corrosion

task in each airplane area to be performed by

the new operator must be accomplished in

accordance with the previous operator’s

schedule or with the new operator’s

schedule, whichever would result in the

earlier accomplishment date for that task.

After each corrosion task has been performed

once, each subsequent task must be

performed in accordance with the new

operator’s schedule.

(2) For airplanes that have not been

previously maintained in accordance with

this AD, the first corrosion task for each

airplane area to be performed by the new

operator must be accomplished prior to

further flight or in accordance with a

schedule approved by the FAA.

(j) Reports of Level 2 and Level 3 corrosion

must be submitted at least quarterly to

Lockheed Aeronautical Systems in

accordance with Section 5 of Revision 4 of

the Document.

Note 15: Reporting of Level 2 and Level 3

corrosion found as a result of any

opportunity inspections is highly desirable.

Alternative Methods of Compliance

(k) 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, Atlanta

Aircraft Certification Office (ACO), FAA.

Operators shall submit their requests through

an appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Atlanta ACO.

Note 16: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Atlanta ACO.

Special Flight Permits

(l) 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.

Issued in Renton, Washington, on April 18,

2001.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 01–10181 Filed 4–24–01; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000–NM–294–AD]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 747 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to certain

Boeing Model 747 series airplanes, that

currently requires inspection of the aft

trunnion of the wing landing gear for

cracks and corrosion, and corrective

action, if necessary. This action would

require new repetitive inspections for

cracks or corrosion of the aft trunnion

outer cylinders of the wing landing gear,

follow-on actions, and repetitive

20764 Federal Register / Vol. 66, No. 80 / Wednesday, April 25, 2001 / Proposed Rules

overhaul of the wing landing gear. The

new actions would also apply to

airplanes not included in the

applicability of the existing AD. The

actions specified by the proposed AD

are intended to find and fix cracking or

corrosion of the aft trunnion of the wing

landing gear, which could result in

collapse of the wing landing gear and

consequent reduced controllability of

the airplane.

DATES: Comments must be received by

June 11, 2001.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 2000–NM–

294–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. Comments may be

submitted via fax to (425) 227–1232.

Comments may also be sent via the

Internet using the following address: 9–

anm-nprmcomment@faa.gov. Comments

sent via fax or the Internet must contain

‘‘Docket No. 2000–NM–294–AD’’ in the

subject line and need not be submitted

in triplicate. Comments sent via the

Internet as attached electronic files must

be formatted in Microsoft Word 97 for

Windows or ASCII text.

The service information referenced in

the proposed rule may be obtained from

Boeing Commercial Airplane Group,

P.O. Box 3707, Seattle, Washington

98124–2207. This information may be

examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Tamara Anderson, Aerospace Engineer,

Airframe Branch, ANM–120S, FAA,

Seattle Aircraft Certification Office,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(425) 227–2771; fax (425) 227–1181.

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 action may be changed in light

of the comments received.

Submit comments using the following

format:

• Organize comments issue-by-issue.

For example, discuss a request to

change the compliance time and a

request to change the service bulletin

reference as two separate issues.

• For each issue, state what specific

change to the proposed AD is being

requested.

• Include justification (e.g., reasons or

data) for each request.

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 action

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 2000–NM–294–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.

2000–NM–294–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

On August 7, 1990, the FAA issued

AD 90–06–18 R1, amendment 39–6706

(55 FR 33650, August 17, 1990),

applicable to certain Boeing Model 747

series airplanes, to require repetitive

inspections of the aft trunnion of the

wing landing gear for cracks and

corrosion, and corrective action, if

necessary. That AD also provides an

optional modification which terminates

the repetitive inspections. That action

was prompted by reports of several

incidents of landing gear collapse due to

corrosion and fatigue cracks. The

requirements of that AD are intended to

prevent such landing gear collapse,

which could result in the inability of the

pilot to safely control the airplane.

Actions Since Issuance of Previous Rule

Since the issuance of AD 90–06–18

R1, the FAA has received several reports

that operators have found cracked or

fractured aft trunnion outer cylinders of

the wing landing gear on airplanes

modified per the optional terminating

action provided in that AD. Cracked or

fractured aft trunnion outer cylinders

could result in collapse of the wing

landing gear and consequent reduced

controllability of the airplane. The FAA

has also determined that this unsafe

condition could occur on all Boeing

Model 747 series airplanes, not just the

airplanes included in the applicability

of the existing AD.

Explanation of Relevant Service

Information

The FAA has reviewed and approved

Boeing Alert Service Bulletin 747–

32A2465, Revision 1, dated July 20,

2000, which describes procedures for

new repetitive detailed visual

inspections using a borescope to find

cracking or corrosion of the aft trunnion

outer cylinders of the wing landing gear,

and follow-on actions. If no cracking or

corrosion is found, the follow-on action

is application of corrosion preventative

compound to the aft trunnion. If any

cracking or corrosion is found, the

service bulletin specifies to contact

Boeing for repair instructions. Flag note

2 of Figure 1 of the service bulletin also

references specific sections of the

Boeing Overhaul Manual for procedures

for repetitive overhaul of the wing

landing gear. Accomplishment of the

actions specified in the service bulletin

is intended to adequately address the

identified unsafe condition.

Explanation of Requirements of

Proposed Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other products of this same

type design, the proposed AD would

supersede AD 90–06–18 R1 to continue

to require, for certain airplanes,

inspection of the aft trunnion of the

wing landing gear for cracks and

corrosion, and corrective action, if

necessary. For all affected airplanes, this

proposed AD would add requirements

for new repetitive inspections for cracks

or corrosion of the aft trunnion outer

cylinders of the wing landing gear,

follow-on actions, and repetitive

overhaul of the wing landing gear. The

actions would be required to be

accomplished in accordance with the

service bulletin described previously,

except as discussed below.

Differences Between Service Bulletin

and Proposed AD

Operators should note that, although

the service bulletin specifies that the

manufacturer may be contacted for

disposition of certain repair conditions,

this proposed AD would require the

repair of those conditions to be

accomplished per a method approved

Federal Register / Vol. 66, No. 80 / Wednesday, April 25, 2001 / Proposed Rules 20765

by the FAA, or per data meeting the

type certification basis of the airplane

approved by a Boeing Company

Designated Engineering Representative

who has been authorized by the FAA to

make such findings.

Cost Impact

There are approximately 1,132

airplanes of the affected design in the

worldwide fleet.

In AD 90–06–18 R1, the FAA

estimated that the actions in that AD

would affect 163 airplanes of U.S.

registry. The actions that are currently

required by AD 90–06–18 R1 take

approximately 45 work hours per

airplane to accomplish, at an average

labor rate of $60 per work hour. Based

on these figures, the FAA estimates the

cost impact of the currently required

actions on U.S. operators to be

$440,100, or $2,700 per airplane, per

inspection cycle.

The FAA estimates that this proposed

AD would affect 233 airplanes of U.S.

registry. The new inspections proposed

in this AD action would take

approximately 8 work hours per

airplane to accomplish, at an average

labor rate of $60 per work hour. Based

on these figures, the FAA estimates the

cost impact of the proposed inspection

on U.S. operators to be $111,840, or

$480 per airplane, per inspection cycle.

The new overhaul proposed in this

AD action would take approximately

320 work hours per airplane to

accomplish, at an average labor rate of

$60 per work hour. Based on these

figures, the FAA estimates the cost

impact of the proposed overhaul on U.S.

operators to be $4,473,600, or $19,200

per airplane, per overhaul.

The cost impact figures discussed

above are 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 proposed AD were not adopted. The

cost impact figures discussed in AD

rulemaking actions represent only the

time necessary to perform the specific

actions actually required by the AD.

These figures typically do not include

incidental costs, such as the time

required to gain access and close up,

planning time, or time necessitated by

other administrative actions.

Regulatory Impact

The regulations proposed herein

would not have a substantial direct

effect 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,

it is determined that this proposal

would not have federalism implications

under Executive Order 13132.

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.

§ 39.13 [Amended]

2. Section 39.13 is amended by

removing amendment 39–6706 (55 FR

33650, August 17, 1990), and by adding

a new airworthiness directive (AD), to

read as follows:

Boeing: Docket 2000–NM–294–AD.

Supersedes AD 90–06–18 R1,

Amendment 39–6706.

Applicability: All Model 747 series

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 (e) 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 find and fix cracking or corrosion of the

aft trunnion of the wing landing gear, which

could result in collapse of the wing landing

gear and consequent reduced controllability

of the airplane, accomplish the following:

Restatement of Requirements of AD

90–06–18 R1

Repetitive Inspections and Corrective Actions

(Certain Airplanes)

(a) For airplanes listed in Groups 1, 2, and

3 in Boeing Service Bulletin 747–32–2190,

Revision 4, dated October 26, 1989, inspect

as follows:

(1) Within the next 120 days after August

17, 1990 (the effective date of AD 90–06–18

R1, amendment 39–6706), perform a visual

inspection, or a visual-plus-eddy-current

inspection, of the wing landing gear at the

trunnion, for cracks and corrosion, in

accordance with Boeing Service Bulletin

747–32–2190, Revision 4, dated October 26,

1989.

(2) If no cracks or corrosion are found,

repeat the inspection described in paragraph

(a)(1) of this AD at intervals not to exceed 6

months if the visual inspection option was

selected for the previous inspection, or at

intervals not to exceed 18 months if the

visual-plus-eddy-current inspection option

was selected for the previous inspection.

Doing paragraph (b), (c), or (d) of this AD

ends the repetitive inspections required by

this paragraph.

(3) Except as provided by paragraph (a)(4)

of this AD, if cracks or corrosion are found,

prior to further flight, remove and rework or

replace cracked/corroded parts in accordance

with Boeing Service Bulletin 747–32–2190,

Revision 4, dated October 26, 1989.

(4) If only corrosion is found, as an

alternative to paragraph (a)(3) of this AD,

accomplish the terminating action described

in Boeing Service Bulletin 747–32–2190,

Revision 4, dated October 26, 1989, within 12

months after detection of corrosion, but no

later than 36 months after August 17, 1990;

and high-frequency-eddy-current inspect the

wing landing gear trunnion at intervals not

to exceed 6 months, until the terminating

action is accomplished. Doing paragraph (b),

(c), or (d) of this AD ends the repetitive

inspections required by this paragraph.

Optional Terminating Action for

Requirements of Paragraph (a)

(b) For airplanes listed in Groups 1, 2, and

3 in Boeing Service Bulletin 747–32–2190,

Revision 4, dated October 26, 1989:

Modification in accordance with Boeing

Service Bulletin 747–32–2190, Revision 4,

dated October 26, 1989, constitutes

terminating action for the reinspection

requirements of paragraph (a) of this AD.

New Requirements of This AD

Repetitive Detailed Visual Inspections and

Follow-On Actions (All Airplanes)

(c) Within 180 days after the effective date

of this AD, do a detailed visual inspection

using a borescope to find cracking and

corrosion of the aft trunnion outer cylinders

of the wing landing gear. Do the inspection

per Figure 2 of Boeing Alert Service Bulletin

747–32A2465, Revision 1, dated July 20,

20766 Federal Register / Vol. 66, No. 80 / Wednesday, April 25, 2001 / Proposed Rules

2000. The detailed visual inspection is

contained in Part 1 of the service bulletin.

Thereafter, repeat the inspection at intervals

not to exceed 6 months.

(1) If no corrosion or cracking is found

during any inspection per paragraph (c) of

this AD, before further flight, apply corrosion

preventative compound, per the service

bulletin. Repeat the application of corrosion

preventative compound after each inspection

per paragraph (c) of this AD.

(2) If any corrosion or cracking is found

during any inspection per paragraph (c) of

this AD, before further flight, repair per a

method approved by the Manager, Seattle

Aircraft Certification Office (ACO), FAA; or

per data meeting the type certification basis

of the airplane approved by a Boeing

Company Designated Engineering

Representative (DER) who has been

authorized by the Manager, Seattle ACO, to

make such findings. For a repair method to

be approved by the Manager, Seattle ACO, as

required by this paragraph, the approval

letter must specifically reference this AD.

Note 2: For the purposes of this AD, a

detailed visual 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.’’

Overhaul (All Airplanes)

(d) At the applicable compliance time

stated in paragraph (d)(1) or (d)(2) of this AD,

and thereafter at intervals not to exceed 10

years, overhaul the wing landing gear per

Flag Note 2 of Figure 1 of Boeing Alert

Service Bulletin 747–32A2465, Revision 1,

dated July 20, 2000. If any cracking or

corrosion outside the overhaul limits is

found during this overhaul, before further

flight, repair per a method approved by the

Manager, Seattle ACO; or per data meeting

the type certification basis of the airplane

approved by a Boeing Company DER who has

been authorized by the Manager, Seattle

ACO, to make such findings. For a repair

method to be approved by the Manager,

Seattle ACO, as required by this paragraph,

the approval letter must specifically

reference this AD. For affected airplanes,

doing this overhaul ends the repetitive

inspections required by paragraph (a) of this

AD.

(1) For Group 1 airplanes listed in Boeing

Alert Service Bulletin 747–32A2465,

Revision 1, on which the wing landing gear

has NOT been modified per Flag Note 1 of

Figure 1 of the service bulletin: Overhaul the

wing landing gear within 48 months after the

effective date of this AD.

(2) For Group 1 airplanes listed in Boeing

Alert Service Bulletin 747–32A2465,

Revision 1, on which the wing landing gear

HAS been modified per Flag Note 1 of Figure

1 of the service bulletin; OR for Groups 2 and

3 airplanes listed in Boeing Alert Service

Bulletin 747–32A2465, Revision 1: Overhaul

the wing landing gear within 10 years since

delivery of the airplane or last overhaul, or

within 180 days after the effective date of this

AD, whichever comes later.

Alternative Methods of Compliance

(e)(1) 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, Seattle

ACO. Operators shall submit their requests

through an appropriate FAA Principal

Maintenance Inspector, who may add

comments and then send it to the Manager,

Seattle ACO.

(2) Alternative methods of compliance,

approved previously in accordance with AD

90–06–18 R1, amendment 39–6706, are

approved as alternative methods of

compliance for paragraphs (a) and (b) of this

AD.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Seattle ACO.

Special Flight Permits

(f) 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.

Issued in Renton, Washington, on April 18,

2001.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 01–10180 Filed 4–24–01; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000–NM–371–AD]

RIN 2120–AA64

Airworthiness Directives; BAE

Systems (Operations) Limited Model

Avro 146–RJ 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 BAE Systems (Operations)

Limited Model Avro 146–RJ series

airplanes. This proposal would require

inspection to detect incorrect wiring of

the fire extinguisher bottles located on

the engines and on the auxiliary power

unit (APU), and corrective action, as

necessary. It would also require

modification of the wiring of the fire

extinguisher bottles located on the

engines and on the APU. This action is

prompted by reports of incorrect wiring

of the fire extinguisher bottles on the

engines and the APU discovered during

routine maintenance. This action is

necessary to prevent the failure of the

fire extinguisher bottles to discharge,

which could result in the inability to

extinguish a fire in the engines or in the

APU.

DATES: Comments must be received by

May 25, 2001.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 2000–NM–

371–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. Comments may be

submitted via fax to (425) 227–1232.

Comments may also be sent via the

Internet using the following address: 9-

anm-nprmcomment@faa.gov. Comments

sent via fax or the Internet must contain

‘‘Docket No. 2000–NM–371–AD’’ in the

subject line and need not be submitted

in triplicate. Comments sent via the

Internet as attached electronic files must

be formatted in Microsoft Word 97 for

Windows or ASCII text.

The service information referenced in

the proposed rule may be obtained from

British Aerospace Regional Aircraft

American Support, 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:

Todd Thompson, Aerospace Engineer,

ANM–116, International Branch, FAA,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–1175;

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 action may be changed in light

of the comments received.