Document ID: FAA-2007-27023-0041
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Pratt&Whitney JT9D Series Turbofan Engines
Posted Date: 2011-11-22T05:00Z

[Federal Register Volume 76, Number 225 (Tuesday, November 22, 2011)]
[Proposed Rules]
[Pages 72130-72132]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-30062]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27023; Directorate Identifier 98-ANE-47-AD]
RIN 2120-AA64

Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede an existing airworthiness directive 
(AD) that applies to all Pratt & Whitney (PW) JT9D series turbofan 
engines. The existing AD 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 opportunity. Since we issued that AD, PW has added mandatory 
inspections for certain critical life-limited parts. This proposed AD 
would require additional revisions to the JT9D series engines ALS 
sections of the manufacturer's ICA. This proposed AD results from the 
need to require enhanced inspection of selected critical life-limited 
parts of JT9D series engines. We are proposing this AD to prevent 
critical life-limited rotating engine part failure, which could result 
in an uncontained engine failure and damage to the airplane.

DATES: We must receive comments on this proposed AD by January 23, 
2012.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Stephen Sheely, Aerospace Engineer, 
Engine & Propeller Directorate, FAA, 12 New England Executive Park, 
Burlington, MA 01803; phone: (781) 238-7750; fax: (781) 238-7199; 
email: stephen.k.sheely@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2007-
27023; Directorate Identifier 98-ANE-47-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    On March 1, 2007, we issued AD 2007-05-17, Amendment 39-14978 (72 
FR 10350, March 8, 2007), for all PW JT9D series turbofan engines. That 
AD requires revisions to the ALS of the manufacturer's ICA to include 
required enhanced inspection of selected critical life-limited parts at 
each piece-part opportunity. We issued that AD to prevent critical 
life-limited rotating engine part failure, which could result in an 
uncontained engine failure and damage to the airplane.

Actions Since Existing AD (72 FR 10350, March 8, 2007) Was Issued

    Since we issued AD 2007-05-17, an FAA study of in-service events 
involving uncontained failures of critical rotating engine parts has 
indicated the need for additional mandatory inspections. The mandatory 
inspections are needed to identify those critical rotating parts with 
conditions which, if allowed to continue in service, could result in 
uncontained engine failures. This proposal would require revisions to 
the JT9D series engines ALS sections of the manufacturer's manuals and 
an air carrier's approved continuous airworthiness maintenance program 
to incorporate additional inspection requirements.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would retain all of the requirements of AD 2007-
05-17 (72 FR 10350, March 8, 2007). This proposed AD would supersede AD 
2007-05-17 to require the following additional inspections:
     Adding eddy current inspections (ECIs) for web cooling 
holes in high-pressure turbine (HPT) stage 1 disks installed in engine 
models JT9D-3A, -7, -7A, -7AH, -7F, -7H, -7J, -20, and -20J engines;
     Adding ECIs for web cooling holes and tierod holes in HPT 
stage 2 disks installed in JT9D-59A and -70A engines;
     Adding ECIs for web cooling holes and tierod holes in HPT 
stage 2 disks installed in JT9D-7Q and -7Q3 engines;
     Adding ECIs for web cooling holes in HPT stage 2 disks, 
and for fan hub

[[Page 72131]]

slots, installed in JT9D-7R4 engines; and
     Adding ECIs for web cooling holes and tierod holes in HPT 
stage 2 disks installed in JT9D-7R4D, -7R4D1, -7R4E, and -7R4E1 
engines.
    This proposed AD would also add the Engine Manual Inspection Task 
and Sub Task Number references for these inspections.

Identifying the Part Nomenclatures and Inspections Added

    For reference, the part nomenclatures and inspections added to the 
table in the compliance section of this proposed AD are identified by 
two asterisks (**) that precede the part nomenclature.

Costs of Compliance

    We estimate that 438 JT9D series engines are installed on airplanes 
of U.S. registry and would be affected by this proposed AD. We also 
estimate that about 4 work hours per engine are needed to perform the 
proposed actions, and that the average labor rate is $85 per work hour. 
Since this is an added inspection requirement that will be part of the 
normal maintenance cycle, no additional parts costs are involved. Based 
on these figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $148,920.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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.
    For the reasons discussed above, I certify that the 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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The FAA amends Sec.  39.13 by removing airworthiness directive 
(AD) 2007-05-17, Amendment 39-14978 (72 FR 10350, March 8, 2007), and 
adding the following new AD:

Pratt & Whitney: Docket No. FAA-2007-27023; Directorate Identifier 
98-ANE-47-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by January 23, 
2012.

(b) Affected ADs

    This AD supersedes AD 2007-05-17, Amendment 39-14978 (72 FR 
10350, March 8, 2007).

(c) Applicability

    This AD applies to Pratt & Whitney (PW) JT9D-3A, -7, -7A, -7H, -
7AH, -7F, -7J, -20J, -59A, -70A, -7Q, -7Q3, -7R4D, -7R4D1, -7R4E, -
7R4E1, -7R4E4, -7R4G2, and -7R4H1 series turbofan engines.

(d) Unsafe Condition

    This AD results from the need to require enhanced inspection of 
selected critical life-limited parts of JT9D series turbofan 
engines. We are issuing this AD to prevent critical life-limited 
rotating engine part failure, which could result in an uncontained 
engine failure and damage to the airplane.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(f) Inspections

    Within the next 30 days after the effective date of this AD, add 
the following section to the Airworthiness Limitations Section (ALS) 
of your copy of the manufacturer's Instructions for Continued 
Airworthiness (ICA) and, for air carrier operations, to your 
continuous airworthiness air carrier maintenance program:

``MANDATORY INSPECTIONS''

    (1) Inspect the following life-limited parts at each piece-part 
opportunity in accordance with the instructions provided in the 
applicable manual provisions:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                        Engine manual part No. (P/                                    Inspect per
             Engine model                           N)                    Part nomenclature         manual section             Inspection/check
--------------------------------------------------------------------------------------------------------------------------------------------------------
3A/7/7A/7AH/7F/7H/7J/20/20J...........  *646028 (or the            All Fan Hubs..................          72-31-04  Inspection-02.
                                         equivalent customized
                                         versions, 770407 and
                                         770408).
                                                                   All HPC Stage 5-15 Disks and            72-35-00  Inspection-03.
                                                                    Rear Compressor Drive Turbine
                                                                    Shafts.
                                                                   All HPT Stage 1-2 Disks and             72-51-00  Inspection-03.
                                                                    Hubs.
                                                                   **All HPT Stage 1 Disk Web              72-51-02  Inspection-06.
                                                                    Cooling Holes.
                                                                   All HPT Stage 2 Disk Web                72-51-02  Inspection-05.
                                                                    Tierod Holes.
                                                                   All LPT Stage 3-6 Disks and             72-52-00  Inspection-03.
                                                                    Hubs.
--------------------------------------------------------------------------------------------------------------------------------------------------------
59A/70A...............................  754459...................  All Fan Hubs..................          72-31-00  Check-00.
                                                                   All HPC Stage 5-15 Disks and            72-35-00  Check-00.
                                                                    Rear Compressor Drive Turbine
                                                                    Shafts.
                                                                   All HPT Stage 1-2 Disks and             72-51-00  Check-03.
                                                                    Hubs.

[[Page 72132]]

 
                                        .........................  All HPT Stage 1 Disk Web                72-51-02  Check-03.
                                                                    Cooling Holes.
                                                                   **All HPT Stage 2 Disk Tierod           72-51-02  Check-04.
                                                                    and Web Cooling Holes.
                                                                   All LPT Stage 3-6 Disks and             72-52-00  Check-03.
                                                                    Hubs.
--------------------------------------------------------------------------------------------------------------------------------------------------------
7Q/7Q3................................  777210...................  All Fan Hubs..................          72-31-00  Inspection-03.
                                                                   All HPC Stage 5-15 Disks and            72-35-00  Inspection-03.
                                                                    Rear Compressor Drive Turbine
                                                                    Shafts.
                                                                   All HPT Stage 1-2 Disks and             72-51-00  Inspection-03.
                                                                    Hubs All HPT Stage 1 Disk Web          72-51-06  Inspection-03.
                                                                    Cooling Holes.
                                                                   **All HPT Stage 2 Disk Tierod           72-51-07  Inspection-03.
                                                                    and Web Cooling Holes.
                                                                   All LPT Stage 3-6 Disks and             72-52-00  Inspection-03.
                                                                    Hubs.
--------------------------------------------------------------------------------------------------------------------------------------------------------
7R4 ALL...............................  785058, 785059, and        All Fan Hubs..................          72-31-00  Inspection/Check-03.
                                         789328.
                                                                   **All Fan Hub Slots...........          72-31-01  Inspection/Check-02.
                                                                   All HPC Stage 5-15 Disks and            72-35-00  Inspection/Check 03.
                                                                    Rear Compressor Drive Turbine
                                                                    Shafts.
                                                                   All HPT Stage 1-2 Disks and             72-51-00  Inspection/Check 03.
                                                                    Hubs.
                                                                   All LPT Stage 3-6 Disks and             72-52-00  Inspection/Check 03
                                                                    Hubs.
                                                                   **All HPT Stage 2 Disk Tierod           72-51-07  Inspection/Check-02.
                                                                    and Web Cooling Holes.
--------------------------------------------------------------------------------------------------------------------------------------------------------
7R4D/D1/E/E1..........................  785058 and 785059........  All HPT Stage 1 Disk Web                72-51-06  Inspection/Check-02.
                                                                    Cooling Holes.
                                                                   **All HPT Stage 2 Disk Tierod           72-51-07  Inspection/Check-02.
                                                                    and Web Cooling Holes.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* P/N 770407 and 770408 are customized versions of P/N 646028 engine manual.
** Two asterisks identify the part nomenclatures and inspections added to the table.

    (2) For the purposes of these mandatory inspections, piece-part 
opportunity means:
    (i) The part is considered completely disassembled when 
disassembly is in accordance with the disassembly instructions in 
the manufacturer's engine shop manual; 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.''
    (g) Except as provided in paragraph (h) 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.

(g) Alternative Methods of Compliance (AMOC)

    (1) You must perform these mandatory inspections using the ALS 
of the ICA and the applicable Engine Manual, unless you receive 
approval to use an AMOC under paragraph (h)(2) of this AD. Section 
43.16 of the Federal Aviation Regulations (14 CFR 43.16) may not be 
used to approve alternative methods of compliance or adjustments to 
the times in which these inspections must be performed.
    (2) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD, if 
requested using the procedures found in 14 CFR 39.19.

(h) Maintaining Records of the Mandatory Inspections

    (1) You have met the requirements of this AD when you revise 
your copy of the ALS of the manufacturer's ICA as specified in 
paragraph (f) of this AD. For air carriers operating under part 121 
of the Federal Aviation Regulations (14 CFR part 121), you have met 
the requirements of this AD when you modify your continuous 
airworthiness air carrier maintenance program as specified in 
paragraph (f) of this AD. You do not need to record each piece-part 
inspection as compliance to this AD, but you must maintain records 
of those inspections according to the regulations governing your 
operation. For air carriers operating under part 121, you may use 
either the system established to comply with section 121.369 or an 
alternative accepted by your principal maintenance inspector if that 
alternative:
    (i) Includes a method for preserving and retrieving the records 
of the inspections resulting from this AD;
    (ii) Meets the requirements of section 121.369(c); and
    (iii) Maintains the records either indefinitely or until the 
work is repeated.
    (2) These record keeping requirements apply only to the records 
used to document the mandatory inspections required as a result of 
revising the ALS of the manufacturer's ICA as specified in paragraph 
(f) of this AD. These record keeping requirements do not alter or 
amend the record keeping requirements for any other AD or regulatory 
requirement.

(i) Related Information

    For more information about this AD, contact Stephen Sheely, 
Aerospace Engineer, Engine & Propeller Directorate, FAA, 12 New 
England Executive Park, Burlington, MA 01803; phone: (781) 238-7750; 
fax: (781) 238-7199; email: stephen.k.sheely@faa.gov.

    Issued in Burlington, Massachusetts, on November 15, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-30062 Filed 11-21-11; 8:45 am]
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