AD 2002-21-17

[Federal Register Volume 67, Number 207 (Friday, October 25, 2002)]
[Rules and Regulations]
[Pages 65495-65497]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 02-27183]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NE-11-AD; Amendment 39-12924; AD 2002-21-17]
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) that 
is applicable to certain Pratt & Whitney (PW) JT8D-200 series turbofan 
engines. This amendment requires the installation of stops on the fan 
exit guide vane case. This amendment is prompted by reports of the 
flange between the fan duct case and the fan exit guide vane case 
separating due to a fan blade fracture event. The actions specified by 
this AD are intended to prevent the flange between the fan duct case 
and the fan exit guide vane case from separating due to a fan blade 
failure. Separations of that flange could result in damage to the 
airplane.

DATES: Effective November 29, 2002. The incorporation by reference of 
certain publications listed in the regulations is approved by the 
Director of the Federal Register as of November 29, 2002.

ADDRESSES: The service information referenced in this AD 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, by appointment, 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,

[[Page 65496]]

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 AD that is 
applicable to Pratt & Whitney (PW) JT8D-200 series turbofan engines was 
published in the Federal Register on July 10, 2002 (67 FR 45680). That 
action proposed to require the installation of stops on the fan exit 
guide vane case in accordance with Pratt & Whitney (PW) service 
bulletin No. 6100, Revision 2, dated December 9, 1998.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Exemption of Stops for Improved Fan Blade Incorporations

    One commenter states that the fan exit guide vane case stops should 
not be required for engines that incorporate the improved fan blades 
required by AD 99-10-11. The commenter states that the installation of 
the improved fan blades prevents fan blade failures which cause fan 
case failures; therefore, the stops should not be required once the 
improved fan blades are incorporated.
    The FAA does not agree. It is true that the fan blade modification 
mandated by AD 99-10-11 greatly improves the durability of the fan 
blades. However, the modifications cannot guarantee that a fan blade 
will never be released for any cause. Further, airworthiness standards 
for engines require that the design and construction of engines be such 
that failure of the most critical fan blade does not lead to an unsafe 
condition. Separation of the fan exit guide vane case from the fan duct 
assembly can lead to a number of unsafe conditions that hazard the 
aircraft. The intent of this AD is to return the engine to the level of 
safety prescribed by the airworthiness standards in the Code of Federal 
Regulations.

Change Definition of Shop Visit

    Two commenters state that the definition of shop visit should be 
changed to exclude line-maintenance type shop visits.
    The FAA agrees. The shop visit definition has been changed in this 
final rule.

Increased Operational Costs

    One commenter states that the installation of the stops will add 
additional weight that will increase the operational costs associated 
with increased annual fuel requirements and therefore this AD should 
not be issued.
    The FAA does not agree. While the annual fuel burn requirements may 
increase due to additional weight, the FAA has determined that this 
potential cost increase is outweighed by the increase in safety that 
will result from the lower risk of aircraft damage after the 
installation of the stops.

Applicability Clarification

    One commenter states that the applicability section needs 
clarification to indicate which case and duct part numbers the stops 
must be installed on.
    The FAA agrees. The applicability has been changed to state the 
part numbers for the cases and the ducts that will require the 
installation of the stops in the AD.

Allow Additional Options for Rubber Strips

    One commenter states that the AD should allow additional options 
for rubber strips on the forward ID of each stop to prevent vibration 
instead of using silicone and allow bolt hole clocking options for the 
stops. The commenter states that the silicone is cumbersome to apply 
and difficult to remove, and the clocking options are requested to 
prevent interference with brackets or case repairs.
    The FAA does not agree. The FAA is not familiar with the details of 
the design changes being requested, however, we will evaluate them as 
an alternate method of compliance if submitted in accordance with 
paragraph (d) of this AD.

Previous SB Compliance To Constitute AD Compliance

    One commenter requests that compliance with the previous SB's PW 
ASB 6100, Original and Revision 1, constitute compliance with the AD. 
Many of the commenter's engines have already complied to the earlier 
SB's.
    The FAA agrees. Credit for compliance to earlier revisions of PW 
ASB 6100 has been added to this final rule.

Agreement With Proposal as Written

    The National Transportation Safety Board agrees with the proposal 
as written.
    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 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 1,346 PW JT8D-200 series engines of the 
affected design in the worldwide fleet. The FAA estimates that 821 
engines installed on airplanes of U.S. registry would be affected by 
this AD. The FAA also estimates that it would take approximately 1.5 
work hours per engine to perform the actions, and that the average 
labor rate is $60 per work hour. Required parts would cost 
approximately $5,200 per engine. Based on these figures, the total cost 
of the AD to U.S. operators is estimated to be $4,343,090.

Regulatory Analysis

    This final rule does not have federalism implications, as defined 
in Executive Order 13132, because it would 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. Accordingly, 
the FAA has not consulted with state authorities prior to publication 
of this final rule.
    For the reasons discussed above, I certify that this action (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) 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 
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, 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:


[[Page 65497]]


    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
to read as follows:

2002-21-17 Pratt & Whitney: Amendment 39-12924. Docket No. 2002-NE-
11-AD.

    Applicability: This airworthiness directive (AD) is applicable 
to Pratt & Whitney (PW) JT8D-209, -217, -217A, -217C, and -219 
series turbofan engines that do not incorporate the fan exit guide 
vane case, part number (P/N) 805919 or 815377, and the improved 
durability and impact resistant fan duct assembly, P/N 805918-01. 
These engines are installed on, but not limited to McDonnell Douglas 
MD-80 and series airplanes.

    Note 1: This 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: Compliance with this AD is required as indicated, 
unless already done.
    To prevent the flange between the fan duct and the fan exit 
guide vane from separating due to a fan blade failure, which could 
result in damage to the airplane, do the following:

Installation of Hardware

    (a) At the next shop visit after the effective date of this AD, 
install stops on the fan exit guide vane case in accordance with 
paragraphs 2.A. through 2.C.(1) of the Accomplishment Instructions 
of Pratt & Whitney (PW) service bulletin (SB) No. 6100, Revision 2, 
dated December 9, 1998.
    (b) Engines that have had stops installed using PW SB No. 6100, 
Revision 1 dated April 9, 1992, or original issue dated November 9, 
1992, are considered to be in compliance with paragraph (a) of this 
AD.

Definitions

    (c) For the purposes of this AD, a shop visit is defined as an 
engine removal, where engine maintenance entails separation of pairs 
of major mating engine flanges or the removal of a disk, hub, or 
spool at a maintenance facility regardless of other planned 
maintenance except as follows:
    (1) Engine removal for the purpose of performing field 
maintenance type activities at a maintenance facility in lieu of 
performing them on-wing is not a shop visit.
    (2) Separation of flanges of the combustion chamber and turbine 
fan duct assembly (split flanges) for the purpose of accessing non-
rotating accessory hardware is not a shop visit.
    (3) Separation of flanges for the purpose of shipment without 
subsequent internal maintenance is not a shop visit.

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 (ECO). 
Operators must submit their request through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, 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.

Special Flight Permits

    (e) Special flight permits may be issued in accordance with 
Sec. Sec.  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 done.

Documents That Have Been Incorporated By Reference

    (f) The installations must be done in accordance with Pratt & 
Whitney (PW) Service Bulletin No. 6100, Revision 2, dated December 
9, 1998. 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) 565-6600, 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.

Effective Date

    (g) This amendment becomes effective on November 29, 2002.

    Issued in Burlington, Massachusetts, on October 18, 2002.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 02-27183 Filed 10-24-02; 8:45 am]
BILLING CODE 4910-13-P