This section of the FEDERAL REGISTER

contains notices to the public of the proposed

issuance of rules and regulations. The

purpose of these notices is to give interested

persons an opportunity to participate in the

rule making prior to the adoption of the final

rules.

Proposed Rules Federal Register

25179

Vol. 63, No. 88

Thursday, May 7, 1998

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–ANE–21–AD]

RIN 2120–AA64

Airworthiness Directives; Pratt &

Whitney JT9D Series Turbofan Engines

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 Pratt & Whitney (PW) JT9D

series turbofan engines. This proposal

would require a one–time acid etch

inspection of the turbine exhaust case

(TEC) wall between and on either side

of the ‘‘R’’ and ‘‘S’’ rails in the engine

mount lug area (top quadrant of the

case) for the presence of weld material,

and if weld material is detected,

removal from service and replacement

with serviceable parts. This proposal is

prompted by reports of weld rework

performed in the outer case wall of the

TEC, in the mount lug fillet area, during

original production to address local

under minimum wall thickness

conditions which have left the TEC’s

structural capability compromised. The

actions specified by the proposed AD

are intended to prevent TEC structural

failure under abnormal operating

conditions, which could result in

reduced main mount load capability,

which could result in an engine

separating from the wing and

subsequent loss of control of the aircraft.

DATES: Comments must be received by

July 6, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), New England

Region, Office of the Regional Counsel,

Attention: Rules Docket No. 98–ANE–

21–AD, 12 New England Executive Park,

Burlington, MA 01803–5299. Comments

may also be sent via the Internet using

the following address: ‘‘9-adengineprop@faa.dot.gov’’. Comments

sent via the Internet must contain the

docket number in the subject line.

Comments may be inspected at this

location between 8:00 a.m. and 4:30

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Pratt & Whitney, 400 Main St., East

Hartford, CT 06108; telephone (860)

565–6600, fax (860) 565–4503. This

information may be examined at the

FAA, New England Region, Office of the

Regional Counsel, 12 New England

Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Tara

Goodman, Aerospace Engineer, Engine

Certification Office, FAA, Engine and

Propeller Directorate, 12 New England

Executive Park, Burlington, MA 01803–

5299; telephone (781) 238–7130, fax

(781) 238–7199.

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

should 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 98–ANE–21–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, New England Region, Office of the

Regional Counsel, Attention: Rules

Docket No. 98–ANE–21–AD, 12 New

England Executive Park, Burlington, MA

01803–5299.

Discussion

The Federal Aviation Administration

(FAA) has received reports of weld

rework performed in the outer case wall

of the turbine exhaust case (TEC), in the

mount lug fillet area, during original

production to address local under

minimum wall thickness conditions

which have left the TEC’s structural

capability compromised on certain Pratt

& Whitney (PW) Models JT9D–7, –7A,

–7H, –7AH, –7F, –7J, –20, –20J, –7Q,

–7Q3, –59A, –70A, and –7R4D turbofan

engines. The investigation identified 24

TECs as having a weld rework

performed to the case wall during

original production to address local

under minimum wall thickness

conditions. Rework procedure

authorization did not limit welding

locations on the circumference of the

case wall and permitted welding either

on the inner diameter or the outer

diameter of the part. A weld rework may

or may not have been performed in the

mount area on the 24 turbine exhaust

cases, only 11 of which have been

identified by serial number (S/N). The

FAA has determined that possibly other

TECs that had the welding rework

procedure have a quality review order

(QRO) number marked on it next to the

part. At this time one of the 24 turbine

exhaust cases (S/N JC4708) has been

located and removed from service.

Engine manual repair allowances were

never intended to authorize welding in

the vicinity of the engine mount lugs

due to structural concerns for engine

mount integrity under abnormal engine

operating conditions. The FAA believes

that the majority of these parts have

been installed in engines; however,

there may be some that are presently not

installed. The manufacturer regards

weld repairs in the turbine exhaust case

wall on either side of the ‘‘R’’ and ‘‘S’’

rails in the engine mount lug area

unacceptable and does not authorize or

accept case wall weld repairs in the
25180 Federal Register / Vol. 63, No. 88/Thursday, May 7, 1998 / Proposed Rules

engine mount lug area. This condition,

if not corrected, could result in TEC

structural failure under abnormal

operating conditions, which could

result in reduced main mount load

capability, which could result in an

engine separating from the wing and

subsequent loss of control of the aircraft.

The FAA has reviewed and approved

the technical contents PW Alert Service

Bulletin (ASB) No. JT9D–A6322,

Revision 1, dated March 19, 1998, and

ASB No. JT9D–7R4–A72–546, Revision

1, dated March 19, 1998, that describe

procedures for acid etch inspections of

the TEC wall between and on either side

of the ‘‘R’’ and ‘‘S’’ rails in the engine

mount lug area (top quadrant of the

case) for the presence of weld material,

and if that material is detected, removal

from service and replacement with

serviceable parts.

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

require, at the next removal of the TEC

from the low pressure turbine case ‘‘P’’

flange for maintenance after the

effective date of this AD, a one-time acid

etch inspection of TEC wall between

and on either side of the ‘‘R’’ and ‘‘S’’

rails in the engine mount lug area (top

quadrant of the case) for the presence of

weld material, and if that material is

detected, removal from service and

replacement with serviceable parts. The

actions would be required to be

accomplished in accordance with the

ASBs described previously.

There are approximately 2,720

engines of the affected design in the

worldwide fleet. The FAA estimates that

1,125 engines installed on aircraft of

U.S. registry would be affected by this

proposed AD, that it would take

approximately 1.4 work hours per

engine to accomplish the proposed

actions, and that the average labor rate

is $60 per work hour. Based on these

figures, the total cost impact of the

proposed AD on U.S. operators is

estimated to be $94,500.

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.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

Pratt & Whitney: Docket No. 98–ANE–21–

AD.

Applicability: Pratt & Whitney (PW)

Models JT9D–7, –7A, –7H, –7AH, –7F, –7J,

–20, –20J, –7Q, –7Q3, –59A, –70A, and

–7R4D turbofan engines. These engines are

installed on but not limited to Boeing 747

and 767 series, McDonnell Douglas DC–10

series, and Airbus Industrie A300 and A310

series aircraft.

Note 1: This airworthiness directive (AD)

applies to each engine 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 engines 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 (b)

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 turbine exhaust case (TEC)

structural failure under abnormal operating

conditions, which could result in reduced

main mount load capability, which could

result in an engine separating from the wing

and subsequent loss of control of the aircraft,

accomplish the following:

(a) At the next removal of the TEC from the

low pressure turbine case ‘‘P’’ flange for

maintenance after the effective date of this

AD, accomplish the following in accordance

with PW Alert Service Bulletin (ASB) No.

JT9D–A6322, Revision 1, dated March 19,

1998, or ASB No. JT9D–7R4–A72–546,

Revision 1, dated March 19, 1998, as

applicable:

(1) Perform a one-time acid etch inspection

of TEC wall between and on either side of the

‘‘R’’ and ‘‘S’’ rails in the engine mount lug

area (top quadrant of the case) for the

presence of weld material.

(2) If weld material is found, remove from

service the TEC and replace with a

serviceable part.

(b) 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, Engine

Certification Office. Operators shall submit

their request through an appropriate FAA

Principal Maintenance Inspector, who may

add comments and then send it to the

Manager, Engine Certification Office.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the Engine

Certification Office.

(c) 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 aircraft to

a location where the inspection requirements

of this AD can be accomplished.

Issued in Burlington, Massachusetts, on

April 29, 1998.

Thomas A. Boudreau,

Acting Manager, Engine and Propeller

Directorate, Aircraft Certification Service.

[FR Doc. 98–12062 Filed 5–6–98; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–SW–43–AD]

Airworthiness Directives; Eurocopter

France SA 330F, G, and J Helicopters

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

Eurocopter France Model SA 330F, G,

and J helicopters. This proposal would

require removal and replacement of

each tail rotor electrical bonding braid

(bonding braid). This proposal is

prompted by one in-service report of