[Federal Register Volume 64, Number 244 (Tuesday, December 21, 1999)]
[Rules and Regulations]
[Pages 71280-71282]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-32506]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NE-32-AD; Amendment 39-11465; AD 99-26-06]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney JT8D-200 Series
Turbofan Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to Pratt & Whitney JT8D-200 series turbofan engines, that
requires 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 requires a one-time boss material
verification, and, if necessary, replacement with serviceable parts.
Finally, this AD requires replacement of CCOCs with welded-on bosses
with improved, one-piece CCOCs. Installation of the one-piece CCOC
constitutes terminating action to the inspection requirements of this
AD. This amendment is prompted by a report of an uncontained engine
failure caused by fatigue cracks originating at the weld joining the
drain boss to the CCOC. The actions specified by this AD are intended
to prevent CCOC cracks, which could result in an uncontained engine
failure and damage to the airplane.
DATES: Effective February 22, 2000.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 22, 2000.
ADDRESSES: The service information referenced in this AD may be
obtained from Pratt & Whitney, 400 Main St., East Hartford, CT 06108;
telephone (860) 565-8770, fax (860) 565-4503. This information may be
examined at the Federal Aviation Administration (FAA), New England
Region, Office of the Regional Counsel, 12 New England Executive Park,
Burlington, MA; or at the Office of the Federal Register, 800 North
Capitol Street, NW, suite 700, Washington, DC.
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: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to include an airworthiness
directive (AD) that is applicable to Pratt & Whitney (PW) JT8D-209, -
217, -217A, -217C, and -219 series turbofan engines was published in
the Federal Register on September 23, 1999 (64 FR 51483). That action
proposed to 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, that AD proposed to require a
one-time boss material verification, and, if necessary, replacement
with serviceable parts. Finally, that AD proposed to 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 the AD. That action was
prompted by a report of an uncontained engine failure caused by fatigue
cracks originating at the weld joining the drain boss to the CCOC. That
condition, if not corrected, could result in CCOC cracks, which could
result in an uncontained engine failure and damage to the airplane.
Comments Received
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Understated Financial Impact
One commenter states that the Federal Aviation Administration (FAA)
has understated the financial impact of the AD by not including the
ancillary costs of removing a cracked CCOC. The FAA does not concur.
The indirect costs associated with this AD are not directly related to
this rule, and, therefore, are not addressed in the economic analysis
for this rule. A full cost analysis for each AD, including such
indirect costs, is not necessary since the FAA has already performed a
cost benefit analysis when adopting the airworthiness requirements to
which these engines were originally certificated. A finding that an AD
is warranted means that the original design no longer achieves the
level of safety specified by those airworthiness requirements, and that
other required actions are necessary, such as inspections of existing
CCOCs and replacement with a one-piece CCOC. Because the original level
of safety was
[[Page 71281]]
already determined to be cost beneficial, these additional requirements
needed to return the engine to that level of safety do not add any
additional regulatory burden, and, therefore, a full cost analysis
would be redundant and unnecessary.
SB Publication Date vs. Effective Date of This AD
The same commenter expresses confusion as to how to compute the
compliance intervals of this AD; specifically, if the effective date of
the AD should be used vs. the publication date of the SB for a
compliance baseline. The FAA concurs. For the purpose of this AD, all
baseline compliance times should be calculated based upon the effective
date of this AD. The FAA has added an explanatory paragraph (c) to this
final rule to explicitly address this issue.
On-Wing Rejection of CCOC and Replacement of CCOC
The same commenter states that there is no clear direction as to
the time interval between an on-wing rejection and the subsequent
removal of the CCOC. The FAA concurs. After an on-wing rejection, the
CCOC must be removed prior to further flight. The FAA has added
explicit phrasing to each inspection paragraph of this final rule to
indicate that there is no operating interval between an on-wing
rejection and the subsequent removal of the CCOC.
Concurrence
One commenter supports the rule as proposed.
New Revision to Service Bulletin (SB)
Since publication of the NPRM, PW has issued Revision 2 to SB No.
6291, dated August 27, 1999. The original version of PW SB No. 6291,
dated May 20, 1997, Revision 1, dated July 9, 1997, or Revision 2,
dated August 27,1999, are all acceptable for performing the terminating
action of installing a one-piece machined CCOC assembly, part number
(P/N) 815556, as stated in paragraph (d) of this final rule.
Conclusion
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule as with the changes described
previously. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
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 will be affected by this proposed AD, that it
will 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 will cost approximately $42,320 per engine. Based
on these figures, the total cost impact of the AD on U.S. operators is
estimated to be $54,361,600.
Regulatory Impact
The regulations adopted herein will 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. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order (E.O.) 13132.
For the reasons discussed above, I certify that this action (1) is
not a ``significant regulatory action'' under E.O. 12866; (2) is not a
``significant rule'' under DOT Regulatory Policies and Procedures (44
FR 11034, February 26, 1979); and (3) 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 final
evaluation has been prepared for this action and it is contained in the
Rules Docket. A copy of it may be obtained from the Rules Docket at the
location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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:
99-26-06 Pratt & Whitney: Amendment 39-11465. Docket 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 (f) 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 prior to further flight,
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, if necessary, replace with serviceable
parts prior to further flight, 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.
Effective Date for Computing Compliance Intervals
(c) For the purpose of this AD, use the effective date of this
AD for computing compliance intervals whenever PW ASB No. A6359,
Revision 1, dated July 30, 1999, refers to the publication date of
the ASB.
Terminating Action
(d) 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
[[Page 71282]]
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
May 20, 1997, or Revision 1 dated July 9, 1997, or Revision 2, dated
August 27,1999. Installation of an improved, one-piece CCOC, P/N
815556, constitutes terminating action to the inspections required
by this AD.
Definition
(e) For the purpose of this AD, part accessibility is defined as
an engine disassembly in which the CCOC is removed from the engine.
Alternative Methods of Compliance
(f) 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.
(g) 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.
Incorporation by Reference
(h) The actions required by this AD shall be done in accordance
with PW ASB No. A6359, Revision 1, dated July 30, 1999, and PW SB
No. 6291, dated May 20, 1997, Revision 1, dated July 9, 1997, and
Revision 2, dated August 27,1999. This incorporation by reference
was approved by the Director of the Federal Register in accordance
with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from
Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone
(860) 565-8770, fax (860) 565-4503. Copies may be inspected at the
FAA, New England Region, Office of the Regional Counsel, 12 New
England Executive Park, Burlington, MA; or at the Office of the
Federal Register, 800 North Capitol Street, NW, suite 700,
Washington, DC.
(i) This amendment becomes effective on February 22, 2000.
Issued in Burlington, Massachusetts, on December 8, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 99-32506 Filed 12-20-99; 8:45 am]
BILLING CODE 4910-13-U
