[Federal Register Volume 64, Number 195 (Friday, October 8, 1999)]
[Proposed Rules]
[Pages 54799-54801]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-26207]



Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-61-AD]
RIN 2120-AA64

Airworthiness Directives; Pratt & Whitney PW2000 Series Turbofan 

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).


SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to Pratt & Whitney (PW) PW2000 
series turbofan engines, that currently requires revisions to the 
engine manufacturers time limits section (TLS) to include 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 in the 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 December 7, 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-61-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: 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.


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-61-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRM's

    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-61-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.


    On April 2, 1999, the Federal Aviation Administration (FAA) issued 
airworthiness directive (AD) 99-08-14, Amendment 39-11120 (64 FR 17949, 
April 14, 1999), to require within the next 30 days after the effective 
date of this AD, revisions to the Time Limits Section (TLS) of the 
Engine Manuals (EM's), and for air carriers the approved continuous 
airworthiness maintenance program, to include required enhanced 
inspection of selected critical life-limited parts at each piece-part 
exposure. That amendment was prompted by a Federal Aviation 
Administration (FAA) study of in-service events involving uncontained 
failures of critical rotating engine parts which indicated the need for 
improved inspections. The improved inspections are needed to identify 
those critical rotating parts with conditions, that if allowed to 
continue in service, could result in uncontained failures. That 
condition, if not corrected, could result in critical life-limited 
rotating engine part failure, which could result in an uncontained 
engine failure and damage to the airplane.

Reason for This Supersedure

    Since the issuance of that AD, additional focused inspection 
procedures for the high pressure turbine (HPT) 1st stage disk and the 
HPT 2nd stage disk have been developed by PW.

Proposed Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Pratt & Whitney (PW) PW2000 series turbofan 
engines of the same type design, this AD supersedes AD 99-08-14 to 
require the additional critical life-limited rotating engine parts to 
be subject to focused inspection at each piece-part opportunity.

Economic Analysis

    There are approximately 812 engines of the affected design in the 
worldwide fleet. The FAA estimates that 677 engines installed on 
aircraft of U.S. registry would be affected by this proposed AD, that 
it would take approximately 8 work hours per engine to accomplish the 
proposed inspections, and that 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 $324,960 ($480 per engine).
    The regulations proposed herein would 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

[[Page 54800]]

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 


    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 39-11120, (64 FR 
17949, April 13, 1999), and by adding a new airworthiness directive.

Pratt & Whitney: Docket No. 98-ANE-61-AD.

    Applicability: Pratt & Whitney (PW) PW2037, PW2040, PW2037M, 
PW2240, PW2337, PW2043, PW2643, and PW2143, series turbofan engines, 
installed on but not limited to Boeing 757 series and Ilyushin IL-
96T 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 
    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 Time Limits section (TLS) of the 
manufacturer's engine manual, Part Numbers (P/N's) 1A6231 and 
1B2412, as appropriate for the PW PW2037, PW2040, PW2037M, PW2240, 
PW2337, PW2043, PW2643, and PW2143 series turbofan engines, and for 
air carriers revise the approved continuous airworthiness 
maintenance program, by adding the following:


    (1) Perform inspections of the following parts at each piece-
part opportunity in accordance with the instructions provided in the 
PW2000 series Engine Manuals:

          Part nomenclature                  Part No. (P/N)        section                Inspection
Hub, 1st Stg Comp....................  1A9001 (Assy P/N 1A9021)    72-31-04  Inspection--06
Disk--HPT 1st Stg....................  1A5301 (Assy. P/N           72-52-00  Inspection/Check--02
Disk--HPT 1st Stg                      1A5301-001 (Assy P/N        72-52-02  Inspection/Check--02
Disk--HPT 1st Stg....................  1B2601 (Assy. P/N           72-52-02  Inspection/Check--02
Disk--HPT 1st Stg....................  1B2601-001 (Assy. P/N       72-52-02  Inspection/Check--02
Disk--HPT 1st Stg....................  1B3601 (Assy. P/N           72-52-02  Inspection/Check--02
Disk--HPT 1st Stg....................  1B3601-001 (Assy. P/N       72-52-02  Inspection/Check--02
Disk--HPT 1st Stg....................  1B7801 (Assy. P/N           72-52-02  Inspection/Check--02
                                        1B7621) Post SB 72-608.
Disk--HPT 2nd Stg....................  1A8302 (Assy. P/N           72-52-02  Inspection/Check--02
Disk--HPT 2nd Stg....................  1B1002 (Assy. P/N           72-52-02  Inspection/Check--02
Hub--HPT 2nd Stg.....................  1B1202 (Assy. P/N 1B1710    72-52-02  Inspection/Check--02
                                        or 1B1172).
Hub--HPT 2nd Stg.....................  1B4902 (Assy. P/N           72-52-02  Inspection/Check--02
Hub--HPT 2nd Stg.....................  1B6602 (Assy. P/N 1B6232    72-52-02  Inspection/Check--02
                                        or 1B7572).
Hub--HPT 2nd Stg.....................  1B8002 (Assy. P/N           72-52-02  Inspection/Check--02

    (2) For the purposes of these mandatory inspections, piece-part 
opportunity means:
    (i) The part is considered completely disassembled when done in 
accordance with the disassembly instructions in the manufacturer's 
engine manual to either part number level listed in the table above, 
    (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 Sec. 43.16 of Federal 
Aviation Regulations (14 CFR 43.16), these enhanced inspections 
shall be performed only in accordance with the TLS of the 
appropriate PW2000 series engine manuals.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Engine Certification Office. 
Operators shall 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.

    (d) Special flight permits may be issued in accordance with 
Secs. 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.
    (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

[[Page 54801]]

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 September 30, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 99-26207 Filed 10-7-99; 8:45 am]