21636 Federal Register / Vol. 65, No. 79 / Monday, April 24, 2000 / Rules and Regulations

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–ANE–41–AD; Amendment

39–11697; AD 2000–08–11]

RIN 2120–AA64

Airworthiness Directives; General

Electric Company CF6–6, CF6–45, and

CF6–50 Series Turbofan Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to General Electric Company

(GE) CF6–6, CF6–45, and CF6–50 series

turbofan engines, that requires revisions

to the Time Limits Section of the

manufacturer’s Instructions for

Continued Airworthiness (ICA) to

include required enhanced inspection of

selected critical life-limited parts at

each piece-part exposure. This action

would add additional eddy current

inspections (ECI) for the high pressure

turbine rotor (HPTR) Stage 1 and 2

disks. This action is prompted by

additional focused inspection

procedures that have been developed by

the manufacturer. The actions specified

by this AD are intended to prevent

critical life-limited rotating engine part

failure, which could result in an

uncontained engine failure and damage

to the airplane.

DATES: Effective date October 23, 2000.

ADDRESSES: The information referenced

in this AD may be examined at the

Federal Aviation Administration (FAA),

New England Region, Office of the

Regional Counsel, 12 New England

Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT:

Karen Curtis, Aerospace Engineer,

Engine Certification Office, FAA, Engine

and Propeller Directorate, 12 New

England Executive Park, Burlington, MA

01803–5299; telephone (781) 238–7192,

fax (781) 238–7199.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39)

by superseding AD 99–08–18,

Amendment 39–11124 (64 FR 17958,

April 13, 1999) which is applicable to

General Electric Company (GE) CF6–6,

CF6–45, and CF6–50 series turbofan

engines was published in the Federal

Register on October 7, 1999 (64 FR

54587). That action proposed to require

disk bore eddy current inspections (ECI)

for the high pressure turbine rotor

(HPTR) Stage 1 and 2 disks.

New Inspection Procedures

Since the issuance of that AD,

additional focused inspection

procedures for other critical life-limited

rotating engine parts have been

developed by GE. This AD will require

modification of the airworthiness

limitations section in the manufacturers

manual and an air carrier’s approved

continuous airworthiness maintenance

program to incorporate these inspection

procedures.

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

comments received.

Objection to the Term ‘‘Unsafe

Condition’’ in the Preamble of the

NPRM

Two commenters object to the

language in the preamble of the NPRM

supersedure for the second phase of

enhanced inspections which includes a

finding of an ‘‘unsafe condition.’’ The

commenters asks that the term ‘‘unsafe

condition’’ be deleted and replaced with

the justification language from the

original NPRM. The FAA does not

agree. The commenter does not disagree

with the proposed rule itself but rather

with the term ‘‘unsafe condition’’ that is

contained in the preamble to the NPRM.

It is not the intent of the FAA to

completely change the enhanced disk

inspection program established by the

current AD, which evolved as a

cooperative effort between the FAA and

industry. This intervention strategy was

designed to reduce the number of

uncontained engine failures by

mandating enhanced nondestructive

inspections of critical rotating

components that could most likely

result in a hazard to the airplane in the

event of a failure. Since the engine

maintenance manuals did not mandate

these enhanced inspections, the current

AD was necessary to establish the

inspection program as an airworthiness

limitation. Regardless of the fact that it

was not stated explicitly in the original

NPRM, the FAA determined that an

‘‘unsafe condition’’ existed because the

engine maintenance manuals did not

contain enhanced inspections as an

airworthiness limitation. There was no

intent to imply any defect in the actual

engine hardware, but simply to state

that the maintenance manuals, that form

part of the approved engine design,

must be revised to mandate the

enhanced inspections. The supersedure

repeats that finding with respect to the

additional parts being added to the

enhanced inspection program. Because

a finding of an ‘‘unsafe condition’’ is

required for the FAA to issue an AD,

future NPRM’s adding parts to the

program will also include that finding.

Requests To Add an Explanation to the

Preamble of This AD, of When the

Inspections Are Not Required

Several commenters request that the

FAA change the preamble that was

published in the NPRM to state when

the enhanced inspections are not

required. The commenters note that the

preamble to this NPRM does not contain

an explanation as to when the enhanced

disk inspections are not required and

express concern that the inspection

program has been changed from the

current AD. The FAA does not agree.

The inspection program established by

the current AD has not been changed.

The NPRM adds additional parts to the

list of parts that must be inspected, and

does not change how air carriers must

manage the inspection program. Future

AD’s may be issued to introduce

additional intervention strategies in

order to further reduce uncontained

engine failures.These may include AD’s

to add new parts to the list of parts to

be inspected. The inspection program

established by the current AD will

remain unchanged unless specifically

changed in a future proposal.

Request to Change All References From

‘‘Time Limits Section’’ to

‘‘Airworthiness Limitations Section’’

One commenter, the engine

manufacturer, asks that we change

references to the ‘‘Time Limits Section’’

to read instead the ‘‘revision to the

Airworthiness Limitations Section.’’

The commenter feels that it is more

accurate to refer to the Airworthiness

Limitation Section since this section,

Chapter 5, now contains two subsets;

05–11 for Time Limits and 05–21 for the

mandatory inspections. The FAA does

not agree. The manufacturer’s current

engine manual does not include the

heading ‘‘Airworthiness Limitations’’

for Chapter 05–00–00 for these engine

models, and the AD directs that changes

be made to the current manual. Should

the manufacturer revise the section

headings in the manual, any future AD’s

could then reference the revised section

headings.

Request for Clarification of When FAA

Approval or AMOC Is Required

One commenter requests clarification

be added to this AD on when equivalent

substitutes for tools, equipment, or

procedures used for performing the

mandatory enhanced inspections

require FAA approval or an approved

alternate method of compliance

(AMOC).

Federal Register / Vol. 65, No. 79 / Monday, April 24, 2000 / Rules and Regulations 21637

The FAA does not agree that further

clarification is necessary in the AD.

When allowed for in an AD, an AMOC

provides a method by which an operator

may secure FAA approval for complying

with the requirements of that AD in a

manner or at a time other than specified

by the AD. This AD, and other similar

AD’s issued as part of the so-called Disk

Inspection Initiative of the Safer Skies

Program, are intended to address the

need to include mandatory detail

inspections in the FAA approved

portion of the engine maintenance

manual. This portion of the engine

maintenance manual is sometimes

referred to as the Airworthiness

Limitations Sections (ALS) of the

Instructions for Continued

Airworthiness. The FAA does not

intend that this AD specify the exact

method or tools with which to conduct

the inspection. Rather, the AD requires

only that the ALS be revised to include

a mandatory opportunistic inspection.

The FAA also does not intend that this

AD change the manner in which

operators seek approval to use tools or

methods of inspections other than those

provided for in the engine

manufacturer’s manual. Operators,

particularly air carriers, should follow

the procedures already in place to

secure FAA review and approval to use

such substitutes, if needed, and to

document that approval if necessary.

Therefore, the AMOC paragraph in the

AD will remain as proposed.

Request To Extend the Comment Period

One commenter requests that the

NPRM comment period be extended

until after the proposed inspections are

published to allow time for the

operators to review the specific

inspections that will be required. The

FAA does not agree. The FAA believes

that the nature and scope of the added

inspections will not be significantly

different from existing inspections. In

addition, the effective date of this AD

has been extended to 180 days after

publication to allow time for the

specific procedures to be published.

Operators may submit comments on the

specific procedures once they are

published and the FAA will consider

extending the effective date further or

additional rulemaking, as necessary.

The FAA does not believe, however,

that this final rule need be delayed

pending the publication of the

inspection procedures.

Request To Allow a Later Effective Date

Several commenters request that the

effective date of the AD be set to allow

sufficient time for publication of the

procedures, equipment procurement

and training necessary to perform the

mandatory inspection. The FAA agrees.

The effective date for the Final rule has

been extended to 180 days after

publication to allow sufficient time for

the publication of the inspection

procedures and for operators to prepare.

Request to Remove ‘‘of This Chapter’’

From Paragraph (e) of the Compliance

Section

One commenter requests that the FAA

remove the statement ‘‘of this chapter’’

from the first sentence of paragraph (e)

of this AD. The commenter feels that

removing the statement will improve

the clarity of the paragraph. The FAA

agrees. The statement ‘‘of this chapter’’

has been removed from the first

sentence of paragraph (e).

Economic Analysis

No comments were received on the

economic analysis contained in the

proposed rules. The FAA has

determined that the annual cost of

complying with this AD does not create

a significant economic impact on small

entities.

Adoption of the Proposed Rule

After careful review of the available

data, including the comments noted

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule with the changes

described previously. The FAA has

determined that these changes will

neither increase the economic burden

on any operator nor increase the scope

of the AD.

Regulatory Impact

This final rule does not have

federalism implications, as defined in

Executive Order 13132, because it does

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. Accordingly, the

FAA has not consulted with state

authorities prior to publication of this

final rule.

For the reasons discussed above, I

certify that this action (1) Is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under DOT

Regulatory Policies and Procedures (44

FR 11034, February 26, 1979); and (3)

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 final evaluation has

been prepared for this action and it is

contained in the Rules Docket. A copy

of it 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, 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.

§ 39.13 [Amended]

2. Section 39.13 is amended by

removing Amendment 39–11124 (64 FR

17958, April 13, 1999), and by adding

a new airworthiness directive,

Amendment 39–11697, to read as

follows:

AD 2000–08–11 General Electric Company:

Amendment 39–11697. Docket No. 98–

ANE–41–AD. Supersedes AD 99–08–18,

Amendment 39–11124.

Applicable Engines

General Electric Company (GE) CF6–6,

CF6–45, and CF6–50 series turbofan engines,

installed on but not limited to Airbus

Industrie A300 series, Boeing 747 series, and

McDonnell Douglas DC–10 series airplanes.

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 (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 critical life-limited rotating

engine part failure, which could result in an

uncontained engine failure and damage to

the airplane, accomplish the following:

Inspections

(a) Within the next 30 days after the

effective date of this AD, revise the

manufacturer’s Time Limitations Section of

the Instructions for Continued Airworthiness

21638 Federal Register / Vol. 65, No. 79 / Monday, April 24, 2000 / Rules and Regulations

(ICA), and for air carrier operations revise the

approved continuous airworthiness

maintenance program, by adding the

following:

‘‘MANDATORY INSPECTIONS

(1) Perform inspections of the following

parts at each piece-part opportunity in

accordance with the instructions provided in

the applicable manual provisions:

Part nomenclature Part No.

(P/N) Inspect per engine shop manual chapter

For CF6–6 Engines:

Disk, Fan Rotor Stage One .................................................. All ................. 72–21–03 Paragraph 2.F. or Paragraph 2.A.B. FluorescentPenetrant Inspect, and 72–21–03 Paragraph 3 or 3.A. Eddy

Current Inspection.

Disk, HPT Rotor Stage One ................................................. All ................. 72–53–03 Paragraph 1. Fluorescent-Penetrant Inspect, and

72–53–03 Paragraph 4. Eddy Current Inspection of the

HPTR Disk Rim Boltholes and 72–53–03 Paragraph 5. Disk

Bore Area Eddy Current Inspection.

Disk, HPT Rotor Stage Two ................................................. All ................. 72–53–04 Paragraph 1. Fluorescent-Penetrant Inspect, and

Paragraph 4. Eddy Current Inspection of the Stage 2 HPTR

Disk Rim Boltholes and 72–53–04 Paragraph 5. Eddy Current Inspection of the Stage 2 Disk Inner Boltholes and 72-

53–04 Paragraph 6. Disk Bore Area Eddy Current Inspection

For CF6–45, CF6–50 Engines:

Disk, Fan Rotor Stage One .................................................. All ................. Task 72–21–03–230–051 Fluorescent Penetrant Inspection,

and Task 72–21–03–250–002–052 Manual Eddy Current Inspection or 72–21–03–250–003–053 Automated Eddy Current Inspection.

Disk, HPT Rotor Stage One ................................................. All ................. Task 72–53–03–230–001–059 Fluorescent-Penetrant Inspect

Disk, and Task 72–53–03–250–052 Eddy Current Inspection

of the HPTR Stage 1 Rim Boltholes, and Task 72–53–03–

250–060, Disk Bore Area Eddy Current Inspection.

Disk, HPT Rotor Stage Two ................................................. All ................. Task 72–53–04–230–001–057 Fluorescent-Penetrant Inspect

Disk, and Task 72–53–04–250–053 Eddy Current Inspection

of the HPTR Stage 2 Rim and/or Inner Boltholes, and Task

72–53–04–250–060, Disk Bore Area Eddy Current Inspection.

(2) For the purposes of these mandatory

inspections, piece-part opportunity means:

(i) The part is considered completely

disassembled when accomplished in

accordance with the disassembly instructions

in the manufacturer’s engine manual; and

(ii) The part has accumulated more than

100 cycles in service since the last piece-part

opportunity inspection, provided that the

part was not damaged or related to the cause

for its removal from the engine.’’

(b) Except as provided in paragraph (c) of

this AD, and notwithstanding contrary

provisions in section 43.16 of the Federal

Aviation Regulations (14 CFR 43.16), these

mandatory inspections shall be performed

only in accordance with the Time Limits

Section of the manufacturer’s ICA.

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 Engine Certification

Office (ECO). Operators shall submit their

requests through an appropriate FAA

Principal Maintenance Inspector, who may

add comments and then send it to the ECO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the ECO.

Ferry Flights

(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.

Continuous Airworthiness Maintenance

Program

(e) FAA-certificated air carriers that have

an approved continuous airworthiness

maintenance program in accordance with the

record keeping requirement of § 121.369 (c)

of the Federal Aviation Regulations (14 CFR

121.369 (c)) must maintain records of the

mandatory inspections that result from

revising the Time Limits Section of the ICA

and the air carrier’s continuous airworthiness

program. Alternately, certificated air carriers

may establish an approved system of record

retention that provides a method for

preservation and retrieval of the maintenance

records that include the inspections resulting

from this AD, and include the policy and

procedures for implementing this alternate

method in the air carrier’s maintenance

manual required by § 121.369 (c) of the

Federal Aviation Regulations (14 CFR

121.369 (c)); however, the alternate system

must be accepted by the appropriate PMI and

require the maintenance records be

maintained either indefinitely or until the

work is repeated. Records of the piece-part

inspections are not required under § 121.380

(a) (2) (vi) of the Federal Aviation

Regulations (14 CFR 121.380 (a) (2) (vi)). All

other Operators must maintain the records of

mandatory inspections required by the

applicable regulations governing their

operations.

Note 3: The requirements of this AD have

been met when the engine shop manual

changes are made and air carriers have

modified their continuous airworthiness

maintenance plans to reflect the

requirements in the engine shop manuals.

(f) This amendment becomes effective on

October 23, 2000.

Issued in Burlington, Massachusetts, on

April 14, 2000.

Jay J. Pardee,

Manager, Engine and Propeller Directorate,

Aircraft Certification Service.

[FR Doc. 00–10158 Filed 4–21–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–ANE–49–AD; Amendment

39–11698; AD 2000–08–12]

RIN 2120–AA64

Airworthiness Directives; General

Electric Company CF6–80A, CF6-80C2,

and CF6–80E1 Series Turbofan

Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain General Electric