[Federal Register Volume 63, Number 251 (Thursday, December 31, 1998)]
[Rules and Regulations]
[Pages 72148-72154]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-34706]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-77-AD; Amendment 39-10975; AD 99-01-08]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT8D and JT3D Series 
Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to Pratt & Whitney (PW) JT8D and JT3D series turbofan 
engines. This action requires operators to remove and replace with 
serviceable parts, certain stage 7 through stage 15 high-pressure 
compressor (HPC) disks identified by part number and serial number. 
This amendment is prompted by a report of an uncontained failure of a 
stage 8 HPC disk during a takeoff roll that resulted in damage to the 
airplane. The actions specified in this AD are intended to prevent the 
failure of a high-pressure compressor disk due to Cadmium 
embrittlement, resulting in uncontained engine failure and damage to 
the airplane.

DATES: Effective January 5, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before March 1, 1999.

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-77-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain the 
docket number in the subject line.
    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 
FAA, New England Region, Office of the Regional Counsel, Burlington, 
MA.

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 (781) 238-7175, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The Federal Aviation Administration (FAA) 
has received a report of an uncontained failure of a stage 8 high-
pressure compressor (HPC) disk, part number (P/N) 787008, installed on 
a Pratt & Whitney (PW) JT8D-9 turbofan engine. The laboratory testing 
revealed that the disk failed as a result of Cadmium embrittlement. 
Nickel-Cadmium (NiCd) coatings are used on JT8D and JT3D steel disks to 
inhibit corrosion. The coating process consists of many steps, the most 
fundamental of which are the electrolytic deposition of a Nickel base 
layer followed eventually by the electrolytic deposition of a Cadmium 
layer. The part is then baked in an oven. During the bake cycle the 
Nickel layer diffuses into the Cadmium which creates an alloy with a 
higher melting temperature than pure Cadmium and immobilizes the 
Cadmium to prevent the liquid metal embrittlement of the steel part. 
The Cadmium rich outer layer acts as the corrosion inhibitor. The 
diffused Nickel acts to immobilize the Cadmium and prevent Cadmium 
embrittlement of the steel. If the Nickel plating is not applied with 
sufficient thickness during the NiCd plating process, the undiffused 
Cadmium can attack the grain boundaries of the base metal. Failure 
results when the disk is exposed to engine operating temperatures and 
stresses. Analysis of this and other Cadmium embrittlement failures 
indicates that a disk exposed to Cadmium embrittlement will likely fail 
within 500 hours time-in-service (TIS). Based on the risks associated 
with a process anomaly at the repair facility that plated the disk, the 
FAA has determined that action is required to remove a number of disks 
plated at that facility since February 1996. The disks most at risk are 
those disks which have accumulated less than 500 hours TIS since they 
were last plated. Disks which have accumulated more than 500 hours TIS 
since plating will not be recalled by this AD. The FAA has identified 
stage 7 through stage 15 HPC disks by P/N and serial number (S/N) that 
have been NiCd plated by the repair facility from February 1996 through 
October 1998. This condition, if not corrected, could result in the 
failure of a high-pressure compressor disk due to Cadmium 
embrittlement, resulting in uncontained engine failure and damage to 
the airplane.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of the same type design, this AD is 
being issued to prevent the failure of a high-pressure compressor disk 
due to Cadmium embrittlement, resulting in uncontained engine failure 
and damage to the airplane. This AD requires removal and replacement of 
certain part-numbered and serial-numbered stage 7 through stage 15 HPC 
disks with serviceable parts.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

[[Page 72149]]

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD 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-77-AD.'' The postcard will be date stamped and 
returned to the commenter.
    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.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, 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.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

99-01-08  Pratt & Whitney: Amendment 39-10975. Docket 98-ANE-77-AD.

    Applicability: Pratt & Whitney (PW) JT8D and JT3D series 
turbofan engines, with stage 7 through stage 15 high-pressure 
compressor (HPC) disks installed, identified by part number (P/N) 
and serial number (S/N) specified in Appendix 1. These engines are 
installed on but not limited to the following aircraft: Boeing 707, 
727, and 737 series airplanes and McDonnell Douglas DC-8, DC-9, and 
MD-80 series airplanes.

Appendix 1

     Disk Part Number and Serial Number (Sorted by Disk Part Number)
------------------------------------------------------------------------
              Stage                 Disk part No.     Disk serial No.
------------------------------------------------------------------------
7................................          701407  7A7271
7................................          701507  4Z2030
7................................          701507  4Z2122
7................................          701507  8Z6454
7................................          766007  8B5265
7................................          774407  B207AA0307
7................................          774407  B207AA0350
7................................          774407  B207AA0379
7................................          774407  B207AA0578
7................................          774407  B207AA0643
7................................          774407  BENCAH1353
7................................          774407  BENCAH2320
7................................          774407  BENCAH2327
7................................          774407  BENCAH2851
7................................          774407  BENCAH4091
7................................          774407  BENCAJ8414
7................................          774407  BENCAJ8440
7................................          774407  BENCAK1631
7................................          774407  BENCAK1684
7................................          774407  BENCAK5135
7................................          774407  BENCAK6623
7................................          774407  BENCAK6643
7................................          774407  BENCAK8115
7................................          774407  H19093
7................................          774407  H19026
7................................          774407  H29904
7................................          774407  J17128
7................................          774407  J17407
7................................          774407  J39120
7................................          774407  J72011
7................................          774407  J72132
7................................          774407  K20050
7................................          774407  K20167
7................................          774407  K78491
7................................          774407  L72139
7................................          774407  M15364
7................................          774407  M15368
7................................          774407  M77985
7................................          774407  M83784
7................................          774407  M93463
7................................          774407  N14127
7................................          774407  N14190
7................................          774407  N14213
7................................          774407  N24114
7................................          774407  N23978
7................................          774407  N24091
7................................          774407  N37879
7................................          774407  N37919
7................................          774407  N70390
7................................          774407  N88161
7................................          774407  N88195
7................................          774407  N88335
7................................          774407  N88342
7................................          774407  N94974
7................................          774407  N95036
7................................          774407  P14716
7................................          774407  P14741
7................................          774407  P35486
7................................          774407  P54563
7................................          774407  P60347
7................................          774407  P60394
7................................          774407  P60446
7................................          774407  P70328
7................................          774407  P81247
7................................          774407  P81253
7................................          774407  P81392
7................................          774407  P81399
7................................          774407  P86295
7................................          774407  P86311
7................................          774407  R03089
7................................          774407  R12413
7................................          774407  R12418
7................................          774407  R12549
7................................          774407  R12557
7................................          774407  R19365
7................................          774407  R31290
7................................          774407  R31411
7................................          774407  R37414
7................................          774407  R37520
7................................          774407  R37554
7................................          774407  R46834
7................................          774407  R46893
7................................          774407  R46918
7................................          774407  R46943
7................................          774407  R47019
7................................          774407  R72171

[[Page 72150]]

 
7................................          774407  R72257
7................................          774407  S05566
7................................          774407  S05610
7................................          774407  S05659
7................................          774407  S10014
7................................          774407  S10050
7................................          774407  S13885
7................................          774407  S13910
7................................          774407  S14048
7................................          774407  S14063
7................................          774407  S14088
7................................          774407  S14173
7................................          774407  S36633
7................................          774407  S36810
7................................          774407  S36857
7................................          774407  S37128
7................................          774407  S37149
7................................          774407  S37168
7................................          774407  S37187
7................................          774407  S37312
7................................          774407  S37367
7................................          774407  S37389
7................................          774407  S37420
7................................          774407  S37469
7................................          774407  S37498
7................................          774407  T04409
7................................          774407  T04526
7................................          774407  T04566
7................................          774407  T04615
7................................          774407  T04632
7................................          774407  T04898
7................................          774407  T04899
7................................          774407  T04988
7................................          774407  T05055
7................................          774407  T05106
7................................      5006007-01  B207AA0068
7................................      5006007-01  B207AA0693
7................................      5006007-01  BENCAH0061
7................................      5006007-01  BENCAH3134
7................................      5006007-01  BENCAJ8558
7................................      5006007-01  BENCAJ8594
7................................      5006007-01  BENCAL0749
7................................      5006007-01  BENCAL2650
7................................      5006007-01  R54586
7................................      5006007-01  R79450
7................................      5006007-01  S11202
7................................      5006007-01  S11206
7................................      5006007-01  S57118
7................................      5006007-01  S57216
7................................      5006007-01  S57519
7................................      5006007-02  BENCAK9643
7................................      5006007-02  BENCAK9690
7................................      5006007-02  BENCAK9697
7................................      5006007-02  BENCAK9705
7................................      5006007-02  BENCAK9723
7................................      5006007-02  BENCAL3657
7................................      5006007-02  BENCAL5478
7................................          774407  BENCAH0521
7................................          774407  BENCAJ8454
7................................          774407  R57626
7................................          774407  T04885
8................................          738308  9B1363
8................................          738308  H03990
8................................          748608  7A9608
8................................          748608  7B9489
8................................          748608  8B0397
8................................          748608  B208AA0030
8................................          748608  B208AA0045
8................................          748608  B208AA0070
8................................          748608  BENCAJ8185
8................................          748608  G30014
8................................          748608  G62624
8................................          748608  G63907
8................................          748608  H29599
8................................          748608  H35085
8................................          748608  H64390
8................................          748608  H84992
8................................          748608  H86520
8................................          748608  J29857
8................................          748608  J29958
8................................          748608  J57418
8................................          748608  J57426
8................................          748608  J57469
8................................          748608  J57532
8................................          748608  J57660
8................................          748608  J57663
8................................          748608  J94763
8................................          748608  J94815
8................................          748608  M54646
8................................          748608  M54770
8................................          748608  M54821
8................................          748608  M54843
8................................          748608  N14562
8................................          748608  N14765
8................................          748608  N84308
8................................          748608  N84314
8................................          748608  N84317
8................................          748608  N84319
8................................          748608  N84373
8................................          748608  N84418
8................................          748608  P26025
8................................          748608  P26136
8................................          748608  P26153
8................................          748608  P26171
8................................          748608  P28471
8................................          748608  P28530
8................................          748608  P28534
8................................          748608  P28564
8................................          748608  P28596
8................................          748608  P28607
8................................          748608  P83853
8................................          748608  P94736
8................................          748608  P98927
8................................          748608  R18995
8................................          748608  R46153
8................................          748608  R73850
8................................          748608  S01136
8................................          748608  S01153
8................................          748608  S01185
8................................          748608  S50692
8................................          748608  S50748
8................................          748608  S78016
8................................          748608  S78066
8................................          748608  S78128
8................................          787008  K51696
8................................          787008  K52389
8................................          787008  L61543
8................................          787008  M76852
8................................          787008  M77423
8................................          787008  M77749
8................................          787008  M77791
8................................          787008  N33354
8................................          787008  N33408
8................................          787008  N33702
8................................          787008  N33760
8................................          787008  N89060
8................................          787008  N89386
8................................          787008  N90133
8................................          787008  N90152
8................................         787008F  N89050
8................................          787208  B228AA0194
8................................          787208  B228AA0343
8................................          787208  B228AA0371
8................................          787208  B228AA0540
8................................          787208  B228AA0574
8................................          787208  B228AA0605
8................................          787208  BENCAH4505
8................................          787208  BENCAH5428
8................................          787208  BENCAH5435
8................................          787208  BENCAJ5724
8................................          787208  BENCAK0065
8................................          787208  BENCAK0066
8................................          787208  BENCAK6165
8................................          787208  BENCAK6359
8................................          787208  BENCAK8796
8................................          787208  BENCAK9253
8................................          787208  BENCAL1567
8................................          787208  BENCAL1571
8................................          787208  BENCAL1579
8................................          787208  BENCAL1887
8................................          787208  BENCAL3339
8................................          787208  BENCAL5283
8................................          787208  BENCAM0672
8................................          787208  J47026
8................................          787208  K12730
8................................          787208  N06609
8................................          787208  N89709
8................................          787208  P43644
8................................          787208  P43665
8................................          787208  P43897
8................................          787208  P43936
8................................          787208  P43950
8................................          787208  P43954
8................................          787208  P44141
8................................          787208  P44694
8................................          787208  P45378
8................................          787208  P45593
8................................          787208  R23192
8................................          787208  R23234
8................................          787208  R23450
8................................          787208  R23452
8................................          787208  R23569
8................................          787208  R23837
8................................          787208  R24172
8................................          787208  R24201
8................................          787208  R24205
8................................          787208  R24390
8................................          787208  R24599
8................................          787208  R24827
8................................          787208  R91709
8................................          787208  S07732
8................................          787208  S39110
8................................          787208  S39281
8................................          787208  S39337
8................................          787208  S39409
8................................          787208  S39410
8................................          787208  S39487
8................................          787208  S39509
8................................          787208  S39534
8................................          787208  S39633
8................................          787208  S39676
8................................          787208  S39721
8................................          787208  S39942
8................................          787208  S39963
8................................          787208  S39996
8................................          787208  S40033
8................................          787208  S40041

[[Page 72151]]

 
8................................          788608  H36177
8................................          788708  7A2254
8................................          789508  G51990
8................................          789608  J46995
8................................          792038  B228AA0331
8................................          792038  B228AA0511
8................................          792038  B228AA1005
8................................          792038  BENCAJ8854
8................................          792038  BENCAJ8871
8................................          796348  K53240
8................................          797938  BENCAL2605
8................................      5005808-01  B228AA0901
8................................      5005808-01  BENCAJ1138
8................................      5005808-01  BENCAJ8902
8................................      5005808-01  S70327
9................................          628209  5X8746
9................................          701509  8Z5256
9................................          701509  9A6145
9................................          701509  H86825
9................................          701509  J00245
9................................          701509  J25666
9................................          701509  J87515
9................................          701509  J89031
9................................          701509  K34309
9................................          701509  K35061
9................................          701509  K55559
9................................          701509  K85824
9................................          701509  L31209
9................................          701509  L31751
9................................          701509  L55770
9................................          701509  M10469
9................................          701509  M40027
9................................          701509  M49712
9................................          701509  M61566
9................................          701509  M84762
9................................          701509  M86342
9................................          701509  M86842
9................................          701509  M86844
9................................          701509  N02758
9................................          701509  N02994
9................................          701509  N209AA0006
9................................          701509  N209AA0080
9................................          701509  N209AA0091
9................................          701509  N209AA0094
9................................          701509  N209AA0255
9................................          701509  N209AA0339
9................................          701509  N209AA0352
9................................          701509  N209AA0561
9................................          701509  N21068
9................................          701509  N21507
9................................          701509  N21508
9................................          701509  N22475
9................................          701509  N22570
9................................          701509  N22591
9................................          701509  N41297
9................................          701509  N42662
9................................          701509  N57120
9................................          701509  N79874
9................................          701509  N79893
9................................          701509  N81317
9................................          701509  N97653
9................................          701509  NENCAH0017
9................................          701509  NENCAH0187
9................................          701509  NENCAH0192
9................................          701509  NENCAH0222
9................................          701509  NENCAH0269
9................................          701509  NENCAH0280
9................................          701509  NENCAH0337
9................................          701509  NENCAH0422
9................................          701509  NENCAH0445
9................................          701509  NENCAH0451
9................................          701509  NENCAH0593
9................................          701509  NENCAH0737
9................................          701509  NENCAH0757
9................................          701509  NENCAH0913
9................................          701509  NENCAH0920
9................................          701509  NENCAH1014
9................................          701509  NENCAH1227
9................................          701509  NENCAH1357
9................................          701509  NENCAH1430
9................................          701509  P11360
9................................          701509  P11370
9................................          701509  P11443
9................................          701509  P11450
9................................          701509  P12878
9................................          701509  P51572
9................................          701509  P52444
9................................          701509  P52971
9................................          701509  P53248
9................................          701509  P77028
9................................          701509  P77207
9................................          701509  P78457
9................................          701509  P97645
9................................          701509  P98143
9................................          701509  P98661
9................................          701509  P98961
9................................          701509  P98991
9................................          701509  R17442
9................................          701509  R18113
9................................          701509  R45676
9................................          701509  R46466
9................................          701509  R72941
9................................          701509  R73009
9................................          701509  R73013
9................................          701509  R73420
9................................          701509  R73464
9................................          701509  R73467
9................................          701509  R73804
9................................          701509  R73934
9................................          701509  S00689
9................................          701509  S00741
9................................          701509  S00777
9................................          701509  S00798
9................................          701509  S18975
9................................          701509  S19201
9................................          701509  S50490
9................................          701509  S77602
9................................          701509  S77616
9................................          701509  S77651
9................................          739509  G79836
9................................          772509  H49185
9................................          772509  K56788
9................................          772509  P97497
9................................          772509  R73983
9................................          772509  S01209
9................................          772509  S50832
9................................          798509  B209AA0539
9................................          798509  BENCAH3770
9................................          798509  BENCAJ9383
9................................          798509  BENCAK9880
9................................          798509  BENCAL0717
9................................          798509  BENCAL0703
9................................          798509  BENCAL2372
9................................          798509  BENCAL6305
9................................          701509  BENCAH0448
9................................         701509N  R18236
9................................          772509  K23767
9................................          798509  BENCAJ9360
9................................          798509  P53159
10...............................          701410  7Z0800
10...............................          701410  7Z0806
10...............................          701810  0A0377
10...............................          701810  3B8966
10...............................          701810  3B9144
10...............................          701810  9Z9847
10...............................          701810  A00862
10...............................          701810  H39339
10...............................          701810  H60642
10...............................          701810  R22292
10...............................         701810G  G82663
10...............................          770510  4B4921
10...............................          770510  G80187
10...............................          772510  B210AA0014
10...............................          772510  B210AA0202
10...............................          772510  B210AA0273
10...............................          772510  B210AA0637
10...............................          772510  B210AA0640
10...............................          772510  B210AA0749
10...............................          772510  B210AA0752
10...............................          772510  B210AA0429
10...............................          772510  BENCAH0251
10...............................          772510  BENCAH1404
10...............................          772510  BENCAJ9735
10...............................          772510  BENCAJ9784
10...............................          772510  BENCAJ9868
10...............................          772510  BENCAK5318
10...............................          772510  BENCAK5762
10...............................          772510  BENCAK5946
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------------------------------------------------------------------------

    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.

[[Page 72154]]

    To prevent the failure of a high-pressure compressor disk due to 
Cadmium embrittlement, resulting in uncontained engine failure and 
damage to the airplane, accomplish the following:
    (a) Remove from service stage 7 through stage 15 high-pressure 
compressor (HPC) disks identified in Appendix 1 of this AD as 
follows:
    (1) For disks with less than 250 hours time in service (TIS) 
since last NiCd plating, remove disk and replace with a serviceable 
part within 100 hours TIS after the effective date of this AD.
    (2) For disks with greater than or equal to 250 hours and less 
than 500 hours TIS since last NiCd plating, remove disk and replace 
with a serviceable part within 150 hours TIS after the effective 
date of this AD.
    (3) For disks with greater than or equal to 500 hours TIS since 
last NiCd plating no action is required.
    (4) Disks removed from service in accordance with this AD are 
not eligible for installation in any engine.
    (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 requests 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 record search requirements of this AD can be accomplished.
    (d) This amendment becomes effective on January 5, 1999.

    Issued in Burlington, Massachusetts, on December 23, 1998.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 98-34706 Filed 12-30-98; 8:45 am]
BILLING CODE 4910-13-P