Federal Register / Vol. 65, No. 25 / Monday, February 7, 2000 / Rules and Regulations 5759

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NE–49–AD; Amendment 39–

11560; AD 2000–03–03]

RIN 2120–AA64

Airworthiness Directives; General

Electric Company CF34 Series

Turbofan Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD), that

requires revisions to the Engine

Maintenance Program specified in the

manufacturer’s Instructions for

Continued Airworthiness (ICA) for

General Electric Company (GE) CF34

series turbofan engines to include

required enhanced inspection of

selected critical life-limited parts at

each piece-part exposure. This AD also

requires that an air carrier’s approved

continuous airworthiness maintenance

program incorporate these inspection

procedures. This amendment is

prompted by a Federal Aviation

Administration (FAA) study of inservice events involving uncontained

failures of critical rotating engine parts

that indicated the need for improved

inspections. The improved inspections

are needed to identify those critical

rotating parts with conditions, which if

allowed to continue in service, could

result in uncontained failures. 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 March 13, 2000.

FOR FURTHER INFORMATION CONTACT:

Kevin Donovan, Aerospace Engineer

Engine Certification Office, FAA, Engine

and Propeller Directorate, 12 New

England Executive Park, Burlington, MA

01803–5299; telephone (781) 238–7743,

fax (238) 238–7199.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to

include an airworthiness directive (AD)

that is applicable to General Electric

Company CF34 series turbofan engines

was published in the Federal Register

on October 7, 1999 (64 FR 54584). That

action proposed to require, within the

next 30 days after the effective date of

this AD, revisions to the CF34 Engine

Maintenance Program specified in the

manufacturer’s Instructions for

Continued Airworthiness (ICA), and, for

air carriers, their approved continuous

airworthiness maintenance program.

General Electric Company, the

manufacturer of CF34–3A1 and –3B1

series turbofan engines, has provided

the FAA with a detailed proposal that

identifies and prioritizes the critical

rotating engine parts with the highest

potential to hazard the airplane in the

event of failure, along with instructions

for enhanced, focused inspection

methods. These enhanced inspections

will be conducted at piece-part

opportunity, as defined in this AD,

rather than at specific inspection

intervals.

Comments Received

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

comments received.

Change Name of Manual Section

One commenter (the manufacturer)

states that the proposal should reference

the Airworthiness Limitations Section

instead of the Time Limits Section. The

FAA concurs in part. The reference to

the Time Limits Section will be

removed and changed to the CF34

Engine Maintenance Program in this

final rule.

Part Numbers (P/Ns)

One commenter notes that in Table

804 of the proposal, the Stage 2 High

Pressure Turbine (HPT) Rotor Disk, P/N

5079T53 is incorrect. The correct P/N is

5079T73. The FAA concurs. To make

this AD consistent with other enhanced

inspection ADs, and in response to

comments received on the other ADs,

the P/Ns have been removed from Table

804 and the word ‘‘all’’ has been

substituted for P/Ns.

Concurs With Proposal

One commenter concurs with the rule

as proposed.

Conclusion

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.

Economic Analysis

The FAA estimates that 352 engines

installed on aircraft of US registry will

be affected by this AD, that it will take

approximately 2 work hours per engine

to accomplish the required actions, and

that the average labor rate is $60 per

work hour. The total cost of the new

inspections per engine will be

approximately $120 per year. Using

average shop visit rates, 275 engines are

expected to be affected per year. The

annual cost impact of the AD on US

operators is therefore estimated to be

$33,000.

Regulatory Impact

The regulations adopted herein will

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 final rule does not

have federalism implications under

Executive Order (EO) 13132.

For the reasons discussed above, I

certify that this action (1) is not a

‘‘significant regulatory action’’ under EO

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

adding the following new airworthiness

directive:

2000–03–03 General Electric Company:

Amendment 39–11560. Docket 99–NE–

49–AD.

Applicability: General Electric Company

(GE) CF34–3A1 and –3B1 series turbofan

5760 Federal Register / Vol. 65, No. 25 / Monday, February 7, 2000 / Rules and Regulations

engines, installed on but not limited to

Bombardier Canadair CL601R (RJ) 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 (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 CF34

Engine Maintenance Program, Chapter 5–21–

00, of the GE CF34 Series Turbofan Engine

Manual, SEI–756, and for air carrier

operations revise the approved continuous

airworthiness maintenance program, by

adding the following:

‘‘9. CF34–3A1 and CF34–3B1 Engine

Maintenance Program—Shop Level

Mandatory Inspection Requirements.

A. This procedure is used to identify

specific piece-parts that require mandatory

inspections that must be accomplished at

each piece-part exposure using the applicable

Chapters referenced in Table 804 for the

inspection requirements.

B. Piece-part exposure is defined as

follows:

(1) For engines that utilize the ‘‘On

Condition’’ maintenance requirements:

The part is considered completely

disassembled when done in accordance with

the disassembly instructions in the GEAE

engine authorized overhaul Engine Manual,

and 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.

(2) For engines that utilize the ‘‘Hard

Time’’ maintenance requirements: The part is

considered completely disassembled when

done in accordance with the disassembly

instructions used in the ‘‘Minor

Maintenance’’ or ‘‘Overhaul’’ instructions in

the GEAE engine authorized Engine Manual,

and 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.

C. Refer to Table 804 below for the

mandatory inspection requirements.

TABLE 804.—MANDATORY INSPECTION REQUIREMENTS

Part nomenclature Manual chapter/section/subject Mandatory inspection

Fan Disk (all) ........................................................................... 72–21–00, Inspection ............................................................ All areas (FPI) 1

Bores (ECI) 2

Stage 1 high pressure turbine (HPT) Rotor Disk (all) ............ 72–46–00, Inspection ............................................................ All areas (FPI) 1

Bores (ECI) 2

Boltholes (ECI) 2

Air Holes (ECI) 2

Stage 2 HPT Rotor Disk (all) .................................................. 72–46–00, Inspection ............................................................ All areas (FPI) 1

Bores (ECI) 2

Boltholes (ECI) 2

Air Holes (ECI) 2

HPT Rotor Outer Torque Coupling (all) .................................. 72–46–00, Inspection ............................................................ All areas (FPI)1

Bore (ECI) 1

1FPI = Fluorescent Penetrant Inspection Method.

2ECI = Eddy Current Inspection.

(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 CF34 Engine

Maintenance Program, Chapter 5–21–00, of

the General Electric Company, CF34 Series

Turbofan Engine Manual, SEI–756.

(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. Operators shall submit their requests

through an appropriate FAA Principal

Maintenance Inspector (PMI), who may add

comments and then send it to the 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.

(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.

(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 CF34 Engine Maintenance

Program 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 manual changes

are made and air carriers have modified their

continuous airworthiness maintenance plans

to reflect the Engine Maintenance Program

requirements specified in the GE CF34 Series

Turbofan Engine Manual.

(f) This amendment becomes effective on

March 13, 2000.

Issued in Burlington, Massachusetts, on

February 1, 2000.

David A. Downey,

Assistant Manager, Engine and Propeller

Directorate, Aircraft Certification Service.

[FR Doc. 00–2687 Filed 2–4–00; 8:45 am]

BILLING CODE 4910–13–P