Airworthiness Directives; Pratt & Whitney JT8D-200 Series Turbofan Engines

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-ANE-08; Amendment 39-10106; AD 97-17-04]

RIN 2120-AA64

Airworthiness Directives; Pratt & Whitney JT8D-200 Series

Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive

(AD), applicable to Pratt & Whitney JT8D-200 series turbofan engines,

that currently requires cleaning of front compressor front hubs (fan

hubs); initial and repetitive eddy current (ECI) and fluorescent

penetrant inspections (FPI) of tierod and counterweight holes for

cracks; removal of bushings; the cleaning and ECI and FPI of bushed

holes for cracks; and, if necessary, replacement with serviceable

parts. In addition, the current AD requires reporting the findings of

cracked fan hubs. This amendment does not change the current AD's

inspection procedures, or the effectivity date that starts the cycle

count for the initial inspection schedules. This AD does, however, add

an additional inspection schedule that requires the initial inspection

of certain fan hubs with standard drilled holes and coolant channel

drilled (CCD) holes to occur earlier than the existing AD requires.

Also, this AD requires reporting the results of the initial fan hub

inspections. This amendment is prompted by additional investigation

since publication of the current AD that reveals that certain fan hubs

with standard drilled holes and CCD holes may be more susceptible to

cracking. The actions specified by this AD are intended to prevent fan

hub failure due to tierod, counterweight, or bushed hole cracking,

which could result in an uncontained engine failure and damage to the

aircraft.

DATES: Effective September 30, 1997.

The incorporation by reference of certain publications listed in

the regulations was previously approved by the Director of the Federal

Register as of March 5, 1997 62 FR 4902, February 3, 1997).

ADDRESSES: The service information referenced in this AD 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 Federal Aviation Administration (FAA), New England

Region, Office of the Assistant Chief Counsel, 12 New England Executive

Park, Burlington, MA 01803-5299; or at the Office of the Federal

Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Christopher Spinney, Aerospace

Engineer, Engine Certification Office, FAA, Engine and Propeller

Directorate, 12 New England Executive Park, Burlington, MA 01803-5299;

telephone (617) 238-7175, fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) by superseding AD 97-02-11,

Amendment 39-9896 (62 FR 4902, February 3, 1997), applicable to Pratt &

Whitney (PW) JT8D-200 series turbofan engines, was published in the

Federal Register on February 24, 1997 (62 FR 8198), and a correction to

a printing error in a table was published on March 31, 1997 (62 FR

15225). That action proposed to require cleaning, initial and

repetitive eddy current inspections (ECI) and fluorescent penetrant

inspections (FPI) for cracks of tierod and counterweight holes; removal

of bushings; the cleaning and initial and repetitive ECI and FPI of

bushed holes for cracks; and, if necessary, replacing with serviceable

parts.

Interested persons have been afforded an opportunity to participate

in the making of this amendment. Due consideration has been given to

the comments received.

Three commenters state that the March 5, 1997, date to begin

counting cycles is objectionable, as a retroactive date is

unenforceable. The FAA concurs in part. The March 5, 1997, date is

supported by a safety risk analysis, but basing the cyclic count on

this date

[[Page 45153]]

would require immediate removal of parts not in compliance at the

effective date of this AD. However, the FAA has reviewed a new risk

analysis that uses the effective date of this AD to begin the cyclic

count for fan hubs added to Table 2 of this AD. This final rule has

been revised by changing the compliance time to ``315 cycles from the

effective date of this AD''. This new date should prevent any fan hubs

from being out of compliance at the date of final rule publication. It

does not, however, extend the compliance time for those fan hubs that

were previously included in AD 97-02-11 and are now listed in Table 2

of this AD. Fan hubs previously included in AD 97-02-11 must perform

initial inspections to the more conservative compliance times.

One group of commenters object to the monthly reporting

requirements required in the proposed rule, as these requirements are

burdensome and do not contribute to safety. The FAA does not concur.

The reports received from these inspections are used to validate the

assumptions used in the safety risk analysis and are critical to the

safety assessment of the inspection program.

One commenter states that alternative methods of compliance (AMOCs)

approved in the current AD should be included in this superseded AD.

The FAA concurs and has added a statement to this final rule that

approves AMOCs from AD 97-02-11 as acceptable for this AD.

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.

There are approximately 2,624 engines of the affected design in the

worldwide fleet. The FAA estimates that 1,279 engines installed on

aircraft of U.S. registry will be affected by this AD, that it will

take 20 work hours per engine for 360 engines to disassemble, remove,

inspect, and reassemble engines, and 4 work hours per engine for 919

engines to inspect at piece-part exposure, and that the average labor

rate is $60 per work hour. Based on these figures, the total cost

impact of the AD on U.S. operators is estimated to be $862,560.

The regulations adopted herein will 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 final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

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, Incorporation by

reference, 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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by removing amendment 39-9896 (62 FR

4902, February 3, 1997) and by adding a new airworthiness directive to

read as follows:

97-17-04 Pratt & Whitney: Amendment 39-10106. Docket 97-ANE-08.

Supersedes AD 97-02-11, Amendment 39-9896.

Applicability: Pratt & Whitney JT8D-209, -217, -217C, and -219

series turbofan engines with front compressor front hub (fan hub),

Part Number (P/N) 5000501-01, installed. These engines are installed

on but not limited to McDonnell Douglas MD-80 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 (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 fan hub failure due to tierod, counterweight, or

bushed hole cracking, which could result in an uncontained engine

failure and damage to the aircraft, accomplish the following:

(a) Inspect fan hubs for cracks in accordance with the

Accomplishment Instructions, Paragraph A, Part 1, and, if

applicable, Paragraph B, of PW ASB No. A6272, dated September 24,

1996, as follows:

(1) For fan hubs identified by Serial Numbers (S/Ns) in Table 2

of this AD, after the fan hub has accumulated more than 4,000 cycles

since new (CSN), as follows:

(i) Initially inspect within 315 cycles in service (CIS) from

the effective date of this AD, or 4,315 CSN, whichever occurs later.

(ii) Thereafter, reinspect after accumulating 2,500 CIS since

last inspection, but not to exceed 10,000 CIS since last inspection.

(2) For fan hubs identified by S/Ns in Appendix A of PW ASB No.

A6272, dated September 24, 1996, after the fan hub has accumulated

more than 4,000 CSN, as follows:

(i) Select an initial inspection interval from Table 1 of this

AD, and inspect accordingly.

Table 1

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Initial inspection Reinspection

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1. Within 1,050 cycles in service (CIS) After accumulating 2,500 CIS

after the effective date of AD 97-02- since last inspection, but not

11, March 5, 1997, or prior to to exceed 6,000 CIS since last

accumulating 5,050 CSN, whichever inspection.

occurs later;

OR

2. Within 990 CIS after the effective After accumulating 2,500 CIS

date of AD 97-02-11, March 5, 1997, or since last inspection, but not

prior to accumulating 4,990 CSN, to exceed 8,000 CIS since last

whichever occurs later; inspection.

[[Page 45154]]

OR

3. Within 965 CIS after the effective After accumulating 2,500 CIS

date of AD 97-02-11, March 5, 1997, or since last inspection, but not

prior to accumulating 4,965 CSN, to exceed 10,000 CIS since

whichever occurs later. last inspection.

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Table 2.--Hubs With Traveler Notations

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Non CCD Non CCD Non CCD Non CCD CCD Hub CCD Hub CCD Hub

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M67663 M67802 P66880 S25545 P66747 R33099 S25292

M67671 M67812 P66885 S25558 P66756 R33107 S25299

M67675 M67826 R32732 S25564 P66800 R33113 S25301

M67681 M67829 R32733 S25598 P66814 R33124 S25302

M67685 M67830 R32735 S25618 P66819 R33131 S25308

M67686 M67831 R32740 S25621 P66831 R33132 S25312

M67687 M67832 R32741 S25637 R32767 R33133 S25316

M67697 M67834 R32810 S25640 R32787 R33136 S25323

M67700 M67843 R32849 T50693 R32792 R33152 S25334

M67706 M67849 R32850 T50752 R32795 R33157 S25335

M67710 M67858 S25222 T50785 R32796 R33163 S25337

M67712 M67866 S25464 T50791 R32800 R33165 S25344

M67713 M67868 S25481 T50792 R32807 R33168 S25369

M67714 M67869 S25483 T50819 R32856 R33171 S25377

M67715 M67872 S25484 T50823 R32860 R33173 S25378

M67716 M67888 S25486 T50827 R32870 R33180 S25381

M67717 N71771 S25488 T50874 R32883 R33181 S25394

M67722 N71804 S25489 T50875 R32905 R33189 S25399

M67723 N71806 S25490 T51058 R32926 R33194 S25402

M67725 N71810 S25491 T51104 R32930 R33198 S25406

M67726 N71811 S25492 .............. R32952 R33201 S25411

M67730 N71875 S25494 .............. R32964 R33202 S25413

M67731 N71876 S25495 .............. R32966 R33207 S25414

M67746 N71921 S25497 .............. R32971 S25193 S25415

M67751 N71965 S25498 .............. R32976 S25195 S25418

M67753 N72062 S25499 .............. R32981 S25207 S25419

M67764 N72126 S25500 .............. R32990 S25208 S25421

M67765 N72152 S25501 .............. R32994 S25221 S25422

M67784 N72162 S25502 .............. R33000 S25229 S25430

M67791 N72207 S25505 .............. R33004 S25238 S25437

M67792 N72216 S25506 .............. R33040 S25246 S25439

M67793 N72219 S25507 .............. R33055 S25248 S25449

M67794 N72242 S25508 .............. R33059 S25250 R33186

M67795 P66693 S25509 .............. R33077 S25256 S25528

M67796 P66695 S25514 .............. R33080 S25262 ..............

M67797 P66696 S25529 .............. R33082 S25268 ..............

M67798 P66698 S25532 .............. R33086 S25278 ..............

M67799 P66699 S25541 .............. R33087 S25287 ..............

M67800 P66737 S25543 .............. R33089 S25288 ..............

M67801 P66753 S25544 .............. R33090 .............. ..............

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(ii) Thereafter, reinspect at intervals that correspond to the

selected inspection interval.

(3) If a fan hub is identified in both Table 2 of this AD and

Appendix A of PW ASB No. A6272, dated September 24, 1996, inspect in

accordance with paragraph (a)(1) or (a)(2) of this AD, whichever

occurs first.

(4) For fan hubs with S/Ns not listed in Table 2 of this AD or

in Appendix A of PW ASB No. A6272, dated September 24, 1996, after

the fan hub has accumulated more than 4,000 CSN, inspect the next

time the fan hub is in the shop at piece-part level, but not to

exceed 10,000 CIS after March 5, 1997.

(5) Prior to further flight, remove from service fan hubs found

cracked or that exceed the bushed hole acceptance criteria described

in PW ASB No. A6272, dated September 24, 1996.

(b) Report the number of completed inspections on a monthly

basis and report findings of cracked fan hubs in accordance with

Accomplishment Instructions, Paragraph F, of Attachment 1 to PW ASB

No. A6272, dated September 24, 1996, within 48 hours after

inspection to Robert Guyotte, Manager, Engine Certification Branch,

Engine Certification Office, FAA, Engine and Propeller Directorate,

12 New England Executive Park, Burlington, MA 01803-5299; telephone

(617) 238-7142, fax (617) 238-7199; Internet:

Robert.G[email protected]. Reporting requirements have been

approved by the Office of Management and Budget and assigned OMB

control number 2120-0056.

(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, Engine Certification Office.

Operators shall forward their requests through an appropriate FAA

Principal Maintenance Inspector, who may add comments and then send

it to the Manager, Engine Certification Office. Alternative methods

of compliance approved for AD 97-02-11 are also considered approved

for this AD.

Note 2: Information concerning the existence of approved

alternative methods of compliance with this AD, 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 aircraft to a location where

the requirements of this AD can be accomplished.

[[Page 45155]]

(e) The actions required by this AD shall be done in accordance

with the following PW ASB:

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Document No. Pages Date

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A6272........................... 1-21 Original.... September 24,

1996.

NDIP-892........................ 1-30 A........... September 15,

1996.

Attachment I.................... AI-1-AI-4 A....... September 15,

1996.

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Total Pages: 55.

This incorporation by reference was previously approved by the

Director of the Federal Register in accordance with 5 U.S.C. 552(a)

and 1 CFR part 51 as of March 5, 1997 (62 FR 4902, February 3,

1997). Copies may be obtained from Pratt & Whitney, 400 Main St.,

East Hartford, CT 06108; telephone (860) 565-6600, fax (860) 565-

4503. Copies may be inspected at the FAA, New England Region, Office

of the Assistant Chief Counsel, 12 New England Executive Park,

Burlington, MA; or at the Office of the Federal Register, 800 North

Capitol Street, NW., suite 700, Washington, DC.

(f) This amendment becomes effective on September 30, 1997.

Issued in Burlington, Massachusetts, on August 12, 1997.

Jay J. Pardee,

Manager, Engine and Propeller Directorate, Aircraft Certification

Service.

[FR Doc. 97-22307 Filed 8-25-97; 8:45 am]

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