AD 2000-21-08

[Federal Register Volume 65, Number 206 (Tuesday, October 24, 2000)]
[Rules and Regulations]
[Pages 63537-63540]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 00-26971]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-48-AD; Amendment 39-11940; AD 2000-21-08]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT8D 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 certain Pratt & Whitney JT8D series turbofan 
engines, that

[[Page 63538]]

currently requires revisions to the Time Limits Section (TLS) of the 
JT8D Turbofan Engine Manual to include required enhanced inspection of 
selected critical life-limited parts at each piece-part exposure. This 
action adds additional critical life-limited parts for enhanced 
inspection. This amendment is prompted by focused inspection procedures 
that have been developed by the manufacturer for additional critical 
life-limited parts. 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 April 23, 2001.

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 
01803; or at the Office of the Federal Register, 800 North Capitol 
Street, NW, suite 700, Washington, DC 20001.

FOR FURTHER INFORMATION CONTACT: Christopher Spinney, Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803; 
telephone: 781-238-7175, fax: 781-238-7199.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 99-12-03, 
Amendment 39-11187 (64 FR 30379, June 8, 1999), which is applicable to 
Pratt & Whitney (PW) JT8D turbofan engines, was published in the 
Federal Register on June 8, 1999 (64 FR 30379). That action proposed to 
require revisions to the Time Limits Section (TLS) of the PW JT8D-1, -
1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -
17AR series Turbofan Engine Manual to include required enhanced 
inspection of selected critical life-limited parts at each piece-part 
exposure.
    Since the issuance of that AD, additional focused inspection 
procedures for other critical life-limited rotating engine parts have 
been developed by PW.

Comments Received

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the four comments received.

Request To Extend the Comment Period

    One commenter requests that the FAA extend the NPRM comment period 
because the required procedures had not been published in the engine 
manual (EM). 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. The extra time until the AD 
becomes effective should also allow the manufacturer to issue a manual 
revision. Operators may submit comments to the docket file 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, or the 
initial compliance time extended to accommodate the manufacturer's 
manual revision cycle.

Request To Remove Part Numbers

    One commenter requests that the FAA remove the part numbers from 
the proposed AD. The commenter feels that the part numbers are 
unnecessary and that eliminating them will minimize the administrative 
burden on the operators. The FAA does not agree. The current structure 
of the JT8D engine manual does not lend itself to reference ``all'' 
part numbers, as does the structure of other engine lines. However, the 
FAA will discuss with Pratt and Whitney the possibility of converting 
the engine manual to incorporate the simpler approach in future 
supersedures of the JT8D enhanced inspection AD.

Request To Remove ``of this chapter'' From Paragraph (e)

    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).

Request To Revise the Definition of Piece-Part Level

    One commenter requests that the FAA revise the definition of piece-
part level to include a debladed high pressure disk (HPT) disk that is 
still attached to the HPT shaft. The commenter incorporates an HPT 
blade management program that does not require unbolting the disk from 
the shaft. The FAA does not agree. The engine manual inspections 
required for an HPT disk at piece-part level do not apply to the disk 
and shaft assembly. The FAA recognizes the need to include the disk and 
shaft assembly to the critical inspection section and are working with 
the manufacturer to develop new inspection criteria. The HPT disk and 
shaft assembly will be considered in a future revision of this enhanced 
inspection initiative.

Economic Analysis

    No comments were received on the economic analysis contained in the 
proposed rules. Based on that analysis, the FAA has determined that the 
annual per engine cost of $60 does not create a significant economic 
impact on small entities.

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.

Regulatory Impact

    This 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 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

[[Page 63539]]

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 39-11187 (64 FR 
30379, June 8, 1999) and by adding a new airworthiness directive, 
Amendment 39-11940, to read as follows:

AD 2000-21-08 Pratt & Whitney: Amendment 39-11940. Docket 98-ANE-48-
AD.

    Applicability: Pratt & Whitney (PW) JT8D-1, -1A, -1B, -7, -7A, -
7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series 
turbofan engines, installed on but not limited to Boeing 727 and 737 
series, and McDonnell Douglas DC-9 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 Time Limits Section (TLS) of the JT8D-1, -1A, -1B, -7, -
7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series 
Turbofan Engine Manual, and for air carrier operations revise the 
approved continuous airworthiness maintenance program, by adding the 
following Critical Life Limited Part Inspection:

    ``A. Inspection Requirements:
    (1) This section has the definitions for individual engine 
piece-parts and the inspection procedures which are necessary when 
these parts are removed from the engine.
    (2) It is necessary to do the inspection procedures of the 
piece-parts in Paragraph B when:
    (a) The part is removed from the engine and disassembled to the 
level specified in paragraph B; and
    (b) The part has accumulated more than 100 cycles since the last 
piece part inspection, provided that the part is not damaged or 
related to the cause of its removal from the engine.
    (3) The inspections specified in this section do not replace or 
make unnecessary other recommended inspections for these parts or 
other parts.
    B. Parts Requiring Inspection:

    Note: Piece-part is defined as any of the listed parts with all 
the blades removed.


------------------------------------------------------------------------
                                                   Engine manual
               Description               -------------------------------
                                              Section       Inspection
------------------------------------------------------------------------
                    Hub (Disk), 1st Stage Compressor
------------------------------------------------------------------------
491201..................................        72-33-31   -02, -03, -04
496501..................................        72-33-31   -02, -03, -04
504101..................................        72-33-31   -02, -03, -04
515201..................................        72-33-31   -02, -03, -04
594301..................................        72-33-31   -02, -03, -04
640501..................................        72-33-31   -02, -03, -04
640601..................................        72-33-31   -02, -03, -04
743301..................................        72-33-31   -02, -03, -04
749701..................................        72-33-31   -02, -03, -04
749801..................................        72-33-31   -02, -03, -04
750001..................................        72-33-31   -02, -03, -04
750101..................................        72-33-31   -02, -03, -04
778901..................................        72-33-31   -02, -03, -04
791401..................................        72-33-31   -02, -03, -04
791501..................................        72-33-31   -02, -03, -04
791601..................................        72-33-31   -02, -03, -04
791701..................................        72-33-31   -02, -03, -04
791801..................................        72-33-31   -02, -03, -04
806001..................................        72-33-31   -02, -03, -04
806101..................................        72-33-31   -02, -03, -04
817401..................................        72-33-31   -02, -03, -04
844401..................................        72-33-31   -02, -03, -04
845401..................................        72-33-31   -02, -03, -04
848001..................................        72-33-31   -02, -03, -04
848101..................................        72-33-31   -02, -03, -04
------------------------------------------------------------------------
                       Disk, 2nd Stage Compressor
------------------------------------------------------------------------
482502..................................        72-33-33             -02
502502..................................        72-33-33             -02
520602..................................        72-33-33             -02
570302..................................        72-33-33             -02
570402..................................        72-33-33             -02
678202..................................        72-33-33             -02
730202..................................        72-33-33             -02
730302..................................        72-33-33             -02
730402..................................        72-33-33             -02
740502..................................        72-33-33             -02
745702..................................        72-33-33             -02
745902..................................        72-33-33             -02
746002..................................        72-33-33             -02
746802..................................        72-33-33             -02
760402..................................        72-33-33             -02
760502..................................        72-33-33             -02
807502..................................        72-33-33             -02
500240201...............................        72-33-33             -02
790832 (Disk assembly)..................        72-33-33             -02
------------------------------------------------------------------------
              Turbine Disk, First Stage With Integral Shaft
------------------------------------------------------------------------
481135..................................        72-52-04             -03
494211..................................        72-52-04             -03
500701..................................        72-52-04             -03
516101..................................        72-52-04             -03
529115..................................        72-52-04             -03
538901..................................        72-52-04             -03
544501..................................        72-52-04             -03
544601..................................        72-52-04             -03
544701..................................        72-52-04             -03
553201..................................        72-52-04             -03
558401..................................        72-52-04             -03
565101..................................        72-52-04             -03
565201..................................        72-52-04             -03
565301..................................        72-52-04             -03
578201..................................        72-52-04             -03
579001..................................        72-52-04             -03
------------------------------------------------------------------------
                 HP Turbine Disk, First Stage, Separable
------------------------------------------------------------------------
587501..................................        72-52-02             -03
5006101-01..............................        72-52-02             -03
578001..................................        72-52-02             -03
5005201-01..............................        72-52-02             -03
696801..................................        72-52-02             -03
742501..................................        72-52-02             -03
752401..................................        72-52-02             -03
767601..................................        72-52-02             -03
792801..................................        72-52-02             -03
856501..................................        72-52-02             -03
832201..................................        72-52-02             -03
855701..................................        72-52-02             -03
856401..................................        72-52-02             -03
5003601-01..............................        72-52-02             -03
5003601-021.............................        72-52-02             -03
5004301-01..............................        72-52-02             -03
------------------------------------------------------------------------

    (b) Except as provided in paragraph (c) of this AD, and 
notwithstanding contrary provisions in 43.16 of the Federal Aviation 
Regulations (14 CFR 43.16), these mandatory inspections shall be 
performed only in accordance with the TLS of the PW JT8D-1, -1A, -
1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -
17AR series Turbofan Engine Manual.

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 Manager, 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 Manager, 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.

Special Flight Permits

    (d) Special flight permits may be issued in accordance with 
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 63540]]

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 TLS of the PW 
JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, 
-17R, and -17AR series Turbofan Engine Manual, 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 
requirements in the PW JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, 
-15, -15A, -17, -17A, -17R, and -17AR series Turbofan Engine Manual.

    (f) This amendment becomes effective on April 23, 2001.

    Issued in Burlington, Massachusetts, on October 16, 2000.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 00-26971 Filed 10-23-00; 8:45 am]
BILLING CODE 4910-13-P