[Federal Register Volume 64, Number 157 (Monday, August 16, 1999)]
[Proposed Rules]
[Pages 44446-44448]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-21178]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-47-AD]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan 
Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Pratt & Whitney 
JT9D series turbofan engines, that currently requires revisions to the 
Airworthiness Limitations Section (ALS) of the manufacturer's 
Instructions for Continued Airworthiness (ICA) to include required 
enhanced inspection of selected critical life-limited parts at each 
piece-part exposure. This action would add additional critical life-
limited parts for enhanced inspection. This proposal is prompted by 
additional focused inspection procedures for other critical life-
limited rotating engine parts that have been developed by the 
manufacturer. The actions specified by this proposed 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: Comments must be received by September 15, 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-47-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ane-
[email protected]''. Comments sent via the Internet must contain the 
docket number in the subject line. Comments may be inspected at this 
location between 8:00 a.m. and 4:30 p.m., Monday through Friday, except 
Federal holidays.

FOR FURTHER INFORMATION CONTACT: Wego Wang, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7134, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal 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-47-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, New England Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 98-ANE-47-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.

Discussion

    On April 13, 1999, the Federal Aviation Administration (FAA) issued 
airworthiness directive (AD) 99-08-12, Amendment 39-11118 (64 FR 17954, 
April 13, 1999), to require revisions to the Time Limits section in the 
Engine Manual (EM) for certain Pratt & Whitney (PW) JT9D series 
turbofan engines 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.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 99-508-512 to require the additional 
critical life-limited rotating engine parts to be subject to focused 
inspection at each piece-part opportunity.
    The FAA estimates that 1,372 engines installed on airplanes of US 
registry would be affected by this proposed AD, that it would take 
approximately 1 work hour per engine to accomplish the proposed 
actions. The average labor rate is $60 per work hour. Based on these 
figures the total cost impact of the proposed AD on U.S. operators is 
estimated to be $82,320.
    The regulations proposed herein would not have substantial direct 
effects

[[Page 44447]]

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 proposal would not 
have sufficient federalism implications to warrant the preparation of a 
Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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 39-11118 (63 FR 
40220, April 13, 1999), and by adding a new airworthiness directive, to 
read as follows:

Pratt & Whitney: Docket No. 98-ANE-47-AD. Supersedes AD 99-08-12, 
Amendment 39-11118.

    Applicability: Pratt & Whitney (PW) JT9D-7, -7A, -7H, -7AH, -7F, 
-7J, -20, -20J, -59A, -70A, -7Q, -7Q3, -7R4D, -7R4D1, -7R4E, -7R4E1, 
-7R4E4, -7R4G2, and -7R4H1 series turbofan engines, installed on but 
not limited to Boeing 747 and 767 series, McDonnell Douglas DC-10 
series, and Airbus Industrie A300 and A310 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:
    (a) Within the next 30 days after the effective date of this AD, 
revise the manufacturer's Airworthiness Limitations Section (ALS) of 
the Instructions for Continued Airworthiness (ICA), and for air 
carrier operations revise the approved continuous airworthiness 
maintenance program, by adding the following:

``Mandatory Inspections''

    (1) Perform inspections of the following parts at each piecepart 
opportunity in accordance with the instructions provided in the 
applicable manual provisions:

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     Engine model (manual P/N)        Part description       Part No.               FPI per inspection
----------------------------------------------------------------------------------------------------------------
7/7A/7AH/7F, 7H/7J/20/20J           Fan Hub (Assy. P/N            648501  72-31-04, Inspection -02.
 (646028*).                          648621 and 665321).
7/7A/7AH/7F, 7H/7J/20/20J           Fan Hub (Assy. P/N            666101  72-31-04, Inspection -02.
 (646028*).                          665321, 719127, and
                                     778621).
7/7A/7AH/7F, 7H/7J/20/20J           Fan Hub (Assy. P/N            690501  72-31-04, Inspection -02.
 (646028*).                          678541,726641, and
                                     778631).
7/7A/7AH/7F, 7H/7J/20/20J           Fan Hub (Assy. P/N            734901  72-31-04, Inspection -02.
 (646028*).                          726941).
59A/70A (754459)..................  Fan Hub (Assy. P/N            745401  72-31-00, Heavy Maintenance Check.
                                     732721, and 804221).
7Q/7Q3 (777210)...................  Fan Hub (Assy. P/N            745401  72-31-00, Inspection -03.
                                     732721, and 804221).
7R4's (785059, 785058, 789328)....  Fan Hub (Assy. P/N        5001701-01  72-31-00, Inspection -03.
                                     5001331-01).
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*P/N 770407 and 770408 are customized versions of P/N 646028 engine manual.


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          Engine model              Part description    FPI per Inspection              FPI per SPOP
----------------------------------------------------------------------------------------------------------------
59A/70A (754459)................  All HPT, 1st disks.  72-51-02, HMC-01...  72-51-00, HMC-03.
                                  All HPT, 2nd Disks.  72-51-02, HCM-02...  72-51-00 HMC-03.
7Q/7Q3 (777210).................  All HPT, 1st Disks.  72-51-06, Insp-01..  72-51-00, Insp-03.
                                  All HPT, 2nd Disks.  72-51-07, Insp-01..  72-51-00, Insp-03.
7/7A/7AH/7F 7H/7J/20/20J          All HPT, 1st Disks.  72-51-02, Insp-01..  72-51-00, Insp-03.
 (646028*).                       All HPT, 2nd Disks.  72-51-02, Insp-03..  72-51-00, Insp-03.
7R4's (785058, 785059, and        All HPT, 1st Disks.  72-51-06, Insp/Chk-  72-51-00, Insp/Chk-03.
 789328).                         All HPT, 2nd Disks.   01.                 72-51-00, Insp/Chk-03.
                                                       72-51-07, Insp/Chk-
                                                        01.
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*P/N 770407 and 770408 are customized versions of P/N 646028 engine manual.

    (2) For the purposes of these mandatory inspections, piece-part 
opportunity means:
    (i) The part is considered completely disassembled when 
accomplished in accordance with the disassembly instructions in the 
manufacturer's engine manual to either part number listed in the 
table above; and
    (ii) The part has accumulated more than 100 cycles in service 
since the last piece-part opportunity inspection, provided that the 
part was not damaged or related to the cause for its removal from 
the engine.''
    (b) Except as provided in paragraph (c) of this AD, and 
notwithstanding contrary provisions in section 43.16 of the Federal 
Aviation Regulations (14 CFR 43.16), these mandatory inspections 
shall be performed only in accordance with the ALS of the 
manufacturer's ICA.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Engine Certification Office (ECO). Operators 
shall submit their requests through an appropriate FAA Principal 
Maintenance Inspector (PMI), who may add comments and then send it 
to the ECO.


[[Page 44448]]


    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the ECO.

    (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 Sec. 121.369 (c) of the Federal 
Aviation Regulations [14 CFR 121.369 (c)] of this chapter must 
maintain records of the mandatory inspections that result from 
revising the Time Limits section of the Instructions for Continuous 
Airworthiness (ICA) and the air carrier's continuous airworthiness 
program. Alternately, certificated air carriers may establish an 
approved system of record retention that provides a method for 
preservation and retrieval of the maintenance records that include 
the inspections resulting from this AD, and include the policy and 
procedures for implementing this alternate method in the air 
carrier's maintenance manual required by Sec. 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 Sec. 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 Engine Manuals.

    Issued in Burlington, Massachusetts, on August 9, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 99-21178 Filed 8-13-99; 8:45 am]
BILLING CODE 4910-13-U