[Federal Register Volume 64, Number 249 (Wednesday, December 29, 1999)]
[Rules and Regulations]
[Pages 72916-72918]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-33566]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-80-AD; Amendment 39-11482; AD 99-27-01]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, 
-217C, and -219 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 (PW) JT8D-209, -217, -217A, -217C, and -
219 series turbofan engines, that requires inspection of the 3rd stage 
and 4th stage low pressure turbine (LPT) blades for shroud notch wear 
and replacement of the blade if wear limits are exceeded. This 
amendment is prompted by a report of an uncontained blade failure. The 
actions specified by this AD are intended to prevent an uncontained 
blade failure that could result in damage to the airplane.

DATES: Effective February 2, 2000.

    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 2, 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 51484). That action 
proposed to require inspection of the 3rd stage and 4th stage low 
pressure turbine (LPT) blades for shroud notch wear and replacement of 
the blade if wear limits are exceeded in accordance with PW Service 
Bulletin (SB) No. 6224, Revision 2, dated August 27, 1998. That action 
was prompted by a report of an uncontained blade failure. That 
condition, if not corrected, could result in an uncontained blade 
failure that could result in 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 from one commenter.

From Earlier to Later

    One commenter wants to change the cyclic and hourly time limits 
from whichever occurs first to whichever occurs later. The commenter 
believes that the later of the cyclic or hourly limits provides an 
adequate level of safety. The Federal Aviation Administration (FAA) 
does not concur. The commenter does not provide the substantiating data 
required to support such a claim. The FAA recognizes that many 
operators manage their engine fleet safely with alternate inspection 
techniques and intervals. The FAA is prepared to grant alternative 
methods of compliance (AMOC) to those operators who submit a request 
with data substantiating that an acceptable level of safety is 
maintained using their program through the AMOC provisions of paragraph 
(d) of this final rule.

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 clarify this issue.

Economic Impact Understated

    The same commenter believes that the economic impact of the AD is 
understated as based upon the numbers presented in the economic 
analysis of the proposal. Specifically, the commenter believes that the 
cost effect of hardware removals after failing an inspection should be 
considered. The FAA concurs and has revised the

[[Page 72917]]

economic analysis to include an estimated cost of the hardware 
replacement. The addition of the costs of blade replacement and 
removals adds an additional $4, 720, 640 per year to the economic 
impact of the AD.

Request for Terminating Action

    Two commenters, including the manufacturer, request that the 
installation of stronger LPT flange bolts be viewed as terminating 
action for the inspections required by this AD. The commenters point to 
a similar terminating action for an inspection requirement for JT8D-1 
through -17AR engines, also intended to address a containment issue. 
The FAA does not concur. While installation of improved LPT bolts will 
provide some increase in containment capability, the improved bolts 
alone are not equivalent to the required inspections for preventing an 
uncontained blade failure in the JT8D-200 series engines. The 
containment issue for the JT8D-1 through -17AR engines was addressed 
through installation of improved bolts and a containment shield. At 
present, there is no similar containment shield available for the JT8D-
200 series engines. In addition, the installation of improved LPT bolts 
is already mandated by AD 99-22-14. The FAA has determined that for the 
JT8D-200 series engines, an uncontained LPT blade failure must be 
addressed through both the installation of improved LPT flange bolts 
and the inspections required by this AD.

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 2,631 engines of the affected design in the 
worldwide fleet. The FAA estimates that 1,279 engines installed on 
aircraft of US registry will be affected by this AD, that it will take 
approximately 1 work hour per engine per year to accomplish the 
required inspections, and that the average labor rate is $60 per work 
hour. Based on these figures, the cost impact for the required 
inspections is estimated to be $76,740 per year. It is estimated that 
10% of the blade sets will fail the inspection per year and require 
replacement. The average cost for a new blade set is $35,500. The new 
blades take approximately 23 work hours to install and the average 
labor rate is $60 per work hour. Based on these figures, the annual 
replacement cost impact of the AD on US operators per year is 
$4,720,640. Therefore the total annual cost impact of the AD on US 
operators is 4,797,380.

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 (EO) 13132.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under EO 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:

99-27-01 Pratt & Whitney: Amendment 39-11482. Docket 98-ANE-80-AD.

    Applicability: Pratt & Whitney (PW) JT8D-209, -217, -217A, -
217C, and -219 series turbofan engines, 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 (d) 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 an uncontained blade failure that could result in 
damage to the airplane, accomplish the following:

Inspection

    (a) For JT8D-209, -217, and -217A engines, perform the 3rd and 
4th stage low pressure turbine (LPT) blade torque inspections in 
accordance with the intervals and procedures described in PW Service 
Bulletin (SB) No. 6224, Revision 2, dated August 27, 1998, 
Accomplishment Instructions, Part 1, A(1) through B(3).
    (b) For JT8D-217C and -219 engines, perform the 4th stage LPT 
blade torque inspection in accordance with the intervals and 
procedures described in PW SB No. 6224, Revision 2, dated August 27, 
1998, Accomplishment Instructions, Part 2, C(1) through C(3).

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 SB No. 6224, 
Revision 2, dated August 27, 1998, refers to the publication date of 
the SB.

Alternative Methods of Compliance

    (d) 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.

Ferry Flights

    (e) 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

    (f) The actions required by this AD shall be done in accordance 
with Pratt & Whitney Service Bulletin No. 6224, Revision 2, dated 
August 27, 1998. This incorporation by

[[Page 72918]]

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.
    (g) This amendment becomes effective on February 2, 2000.

    Issued in Burlington, Massachusetts, on December 20, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 99-33566 Filed 12-28-99; 8:45 am]
BILLING CODE 4910-13-U