[Federal Register Volume 64, Number 194 (Thursday, October 7, 1999)]
[Proposed Rules]
[Pages 54596-54598]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-26213]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-ANE-48-AD]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney JT8D Series Turbofan
Engines
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 certain Pratt & Whitney
JT8D series turbofan engines, that currently requires revisions to the
Time Limits Section (TLS) of the JT8D Turbofan Engine Manuals 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 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 December 6, 1999.
ADDRESSES: Submit comments to the Federal Aviation Administration
(FAA), New England Region, Office of the Regional Counsel, Attention:
Rules Docket No. 98-ANE-48-AD, 12 New England Executive Park,
Burlington, MA 01803-5299. Comments may also be sent via the Internet
using the following address: 9-ane-adcomment@faa.gov''. 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
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 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-48-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-48-AD, 12 New England Executive
Park, Burlington, MA 01803-5299.
Discussion
On June 1, 1999, the Federal Aviation Administration (FAA) issued
airworthiness directive (AD) 99-12-03, Amendment 39-11187 (64 FR 30379,
June 8, 1999), to require revisions to the Time Limits Section (TLS) of
the Pratt & Whitney (PW) JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11,
-15, -15A, -17, -17A, -17R, and -17AR series Turbofan Engine Manuals to
include required enhanced inspection of selected critical
[[Page 54597]]
life-limited parts at each piece-part exposure. That AD was prompted by
a Federal Aviation Administration (FAA) study of in-service events
involving uncontained failures of critical rotating engine parts that
indicated the need for improved inspections. 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.
New Inspection Procedures
Since the issuance of that AD, PW has developed additional focused
inspection procedures. This proposal would add first stage high
pressure (HP) turbine disks and shafts that would require enhanced
inspection at each piece-part exposure.
Proposed Actions
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 99-12-03 to add additional critical
life-limited parts for enhanced inspection at each piece-part
opportunity.
Economic Analysis
The FAA estimates that 5,821 engines installed on airplanes of U.S.
registry would be affected by this proposed AD, that it would take
approximately 8 work hours per engine to perform the enhanced
inspection for the first stage HP turbine disks and shafts. The average
labor rate is $60 per work hour. The cost impact of the added
inspections per engine is approximately $480 per year, with the
approximate total cost for the U.S. fleet of $2,794,080 per year.
Regulatory Impact
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 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 39-11187 (64 FR
30379, June 8, 1999), and by adding a new airworthiness directive, to
read as follows:
Pratt & Whitney: Docket No. 98-ANE-48-AD. Supersedes AD 99-12-03,
Amendment 39-11187.
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 Manuals, 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
[[Page 54598]]
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 section 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 Manuals.
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 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.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the ECO.
Ferry Flights
(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.
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 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 TLS of the PW JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A,
-11, -15, -15A, -17, -17A, -17R, and -17AR series Turbofan Engine
Manuals, 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 PW JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11,
-15, -15A, -17, -17A, -17R, and -17AR series Turbofan Engine
Manuals.
Issued in Burlington, Massachusetts, on September 30, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 99-26213 Filed 10-6-99; 8:45 am]
BILLING CODE 4910-13-P
