[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]
BILLING CODE 4910-13-P