[Federal Register Volume 64, Number 184 (Thursday, September 23, 1999)]
[Proposed Rules]
[Pages 51483-51484]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-24788]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NE-32-AD]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney JT8D-200 Series
Turbofan Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to Pratt & Whitney JT8D-200 series
turbofan engines. This proposal would require initial and repetitive
fluorescent magnetic particle inspections or fluorescent penetrant
inspections of the combustion chamber outer case (CCOC) for cracks,
and, if necessary, replacement with serviceable parts. Also, this AD
would require a one-time boss material verification, and, if necessary,
replacement with serviceable parts. Finally, this AD would require
replacement of CCOCs with welded-on bosses with improved, one-piece
CCOCs. Installation of the one-piece CCOC would constitute terminating
action to the inspection requirements of this AD. This proposal is
prompted by reports of fatigue cracks originating at the weld joining
the drain boss to the CCOC. The actions specified by the proposed AD
are intended to prevent CCOC cracks, which could result in an
uncontained engine failure and damage to the airplane.
DATES: Comments must be received by November 22, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), New England Region, Office of the Regional
Counsel, Attention: Rules Docket No. 99-NE-32-AD, 12 New England
Executive Park, Burlington, MA 01803-5299. Comments may also be sent
via the Internet using the following address:
``[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.
The service information referenced in the proposed rule may be
obtained from Pratt & Whitney, 400 Main St., East Hartford, CT 06108;
telephone (860) 565-6600, fax (860) 565-4503. This information may be
examined at the FAA, New England Region, Office of the Regional
Counsel, 12 New England Executive Park, Burlington, MA.
FOR FURTHER INFORMATION CONTACT: Chris 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 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 99-NE-32-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. 99-NE-32-AD, 12 New England Executive Park,
Burlington, MA 01803-5299.
Discussion
The Federal Aviation Administration (FAA) has received reports of
combustion chamber outer case (CCOC) cracks on Pratt & Whitney (PW)
JT8D-209, -217, -217A, -217C, and -219 series turbofan engines. In one
incident, a PW JT8D-219 engine installed on a McDonnell Douglas MD-80
series aircraft suffered an uncontained engine failure soon after
takeoff, sustaining substantial damage to the engine cowl with some
minor damage to the fuselage. The investigation revealed fatigue cracks
originating at the weld joining a drain boss to the combustion chamber
outer case (CCOC), which subsequently ruptured. This condition, if not
corrected, could result in CCOC cracks, which could result in an
uncontained engine failure and damage to the airplane.
Service Documents
The FAA has reviewed and approved the technical contents of: PW
Alert Service Bulletin (ASB) No. A6359, Revision 1, dated July 30,
1999, that describes procedures for fluorescent magnetic particle
inspections (FMPI) or fluorescent penetrant inspections (FPI) of
certain CCOC bosses for cracks, and a one-time boss material
verification of certain CCOCs identified by serial number (S/N); and PW
Service Bulletin (SB) No. 6291, dated July 9, 1997, that describes
procedures for replacement of CCOCs with welded-on bosses with
improved, one-piece CCOCs.
Proposed Actions
Since an unsafe condition has been identified that is likely to
exist or develop on other engines of this same type design, the
proposed AD would require initial and repetitive FMPI or FPI of the
certain CCOC bosses for cracks, and, if necessary, replacement with
serviceable parts. Also, this AD would require a one-time boss material
[[Page 51484]]
verification of certain CCOCs identified by S/N, and, if necessary,
replacement with serviceable parts. Finally, this AD would require
replacement of CCOCs with welded-on bosses with improved, one-piece
CCOCs. Installation of the one-piece CCOC would constitute terminating
action to the inspection requirements of this AD. The actions would be
required to be accomplished in accordance with the service documents
described previously.
Economic Analysis
There are approximately 2,624 engines of the affected design in the
worldwide fleet. The FAA estimates that 1,280 engines installed on
aircraft of U.S. registry would be affected by this proposed AD, that
it would take approximately 2.5 work hours per engine to accomplish the
proposed inspections and that the average labor rate is $60 per work
hour. Required parts would cost approximately $42,320 per engine. Based
on these figures, the total cost impact of the proposed AD on U.S.
operators is estimated to $54,361,600.
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 adding the following new
airworthiness directive:
Pratt & Whitney: Docket No. 99-NE-32-AD.
Applicability: Pratt & Whitney (PW) JT8D-209, -217, -217A, -
217C, and -219 series turbofan engines with combustion chamber outer
case (CCOC), part numbers (P/Ns) 5000238-01, 797707, 807684, and
815830 installed. These engines are installed on but not limited to
McDonnell Douglas MD-80 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 (e) 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 CCOC cracks, which could result in an uncontained
engine failure and damage to the airplane, accomplish the following:
Inspections
(a) Perform initial and repetitive fluorescent magnetic particle
inspections (FMPI) or fluorescent penetrant inspections (FPI) of
drain bosses and Ps4 bosses of the CCOC for cracks, and, if
necessary replace with serviceable parts, in accordance with the
procedures and intervals specified in paragraph 1.A. of the
Accomplishment Instructions of PW Alert Service Bulletin (ASB) No.
A6359, Revision 1, dated July 30, 1999.
(b) For CCOCs listed by serial number (S/N) in Table 3 of PW ASB
No. A6359, Revision 1, dated July 30, 1999, inspect for proper Ps4
and drain boss material, and replace, if necessary, with serviceable
parts, in accordance with the procedures and intervals specified in
paragraph 1.B. of the Accomplishment Instructions of PW ASB No.
A6359, Revision 1, dated July 30, 1999.
Terminating Action
(c) At the next part accessibility after the effective date of
this AD when the CCOC has accumulated cycles-in-service greater than
the initial inspection threshold specified in table 1 of PW ASB
A6359, Revision 1, dated July 30, 1999, replace the CCOC with a one-
piece machined CCOC assembly, part number (P/N) 815556, in
accordance with PW Service Bulletin (SB) No. 6291, dated July 9,
1997. Installation of an improved, one-piece CCOC, P/N 815556,
constitutes terminating action to the inspections required by this
AD.
Definition
(d) For the purpose of this AD, part accessibility is defined as
an engine disassembly in which the CCOC is removed from the engine.
(e) 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 request 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.
(f) 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 aircraft to a location where
the requirements of this AD can be accomplished.
Issued in Burlington, Massachusetts, on September 16, 1999.
Donald E. Plouffe,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 99-24788 Filed 9-22-99; 8:45 am]
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