[Federal Register Volume 67, Number 182 (Thursday, September 19, 2002)]
[Proposed Rules]
[Pages 59027-59029]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-23776]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NE-30-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: The Federal Aviation Administration (FAA) proposes to adopt a 
new airworthiness directive (AD) that is applicable to Pratt & Whitney 
(PW) JT8D-200 series turbofan engines. This proposal would require 
initial and repetitive visual inspections, fluorescent magnetic 
particle inspections (FMPI), and fretting wear inspections of high 
pressure compressor (HPC) front hubs that have operated with PWA-110 
coating in the interface between the hub and the stage 8-9 spacer. This 
proposal is prompted by the discovery of cracked tierod holes found 
during routine engine overhauls. The actions specified by the proposed 
AD are intended to prevent a rupture of the HPC front hub

[[Page 59028]]

that could result in an uncontained engine failure and damage to the 
airplane.

DATES: Comments must be received by October 21, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 2001-NE-30-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location, by appointment, between 8:00 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. 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.
    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, by appointment, at the FAA, New England Region, Office of the 
Regional Counsel, 12 New England Executive Park, Burlington, MA.

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:

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 action 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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NE-30-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRM's

    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. 2001-NE-30-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.

Discussion

    The FAA has received reports of eighteen cracked PW JT8D-200 series 
HPC front hubs with PWA-110 coating in the interface between the hub 
and the stage 8-9 spacer. The cracks were discovered at engine 
overhauls after the engines had accumulated as few as 9,900 cycles-in-
service. The cracks initiated at the site of fretting wear between the 
interface of the stage 8-9 spacer and the HPC front hub. The results of 
metallurgical examination indicate that the cracks had begun to 
propagate due to low-cycle fatigue (LCF). Eventually these cracks could 
propagate to a critical crack length, causing a rupture of the HPC 
front hub, which could result in an uncontained engine failure and 
damage to the airplane. The FAA has reviewed the statistical evaluation 
of the crack data and has determined that HPC front hubs should be 
inspected using the intervals and procedures outlined in PW Alert 
Service Bulletin (ASB) JT8D A6430, dated September 5, 2002. This 
condition, if not corrected, could result in an uncontained engine 
failure and damage to the airplane.

Manufacturer's Service Information

    The FAA has reviewed and approved the technical contents of PW 
Alert Service Bulletin (ASB) JT8D A6430, dated September 5, 2002, that 
describes procedures for visual, FMPI, and fretting inspections of HPC 
front hubs and replacement of the hubs, if necessary.

FAA's Determination of an Unsafe Condition and Proposed Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other PW JT8D-200 series turbofan engines, this 
proposal would require initial and repetitive visual inspections, 
FMPI's, and fretting wear inspections of HPC front hubs that have 
operated with PWA-110 coating in the interface between the hub and the 
stage 8-9 spacer. The actions would be required to be done in 
accordance with the service bulletin described previously.

Economic Analysis

    There are approximately 2,648 PW JT8D-200 series turbofan engines 
of the affected design in the worldwide fleet. The FAA estimates that 
2,352 engines installed on airplanes of U.S. registry would be affected 
by this proposed AD. The FAA also estimates that it would take 
approximately 6 work hours per engine to perform the proposed 
inspection, and that the average labor rate is $60 per work hour. Based 
on these figures, the total cost of the initial inspection to U.S. 
operators is estimated to be $846,720.

Regulatory Analysis

    This proposed 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 proposed rule.
    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:

[[Page 59029]]

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 and Whitney: Docket No. 2001-NE-30-AD.

Applicability

    This airworthiness directive (AD) is applicable to Pratt & 
Whitney (PW) JT8D-209, -217, -217A, 217C, and -219 series turbofan 
engines that have high pressure compressor (HPC) front hubs 
installed that have operated with PWA-110 coating in the interface 
between the HPC front hub and the stage 8-9 spacer (PWA-110 coating 
applied to either the spacer or the hub) and were manufactured after 
June 1, 1988. These engines are installed on, but not limited to 
McDonnell Douglas MD-80 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 a rupture of the HPC front hub, that could result 
in an uncontained engine failure and damage to the airplane, do the 
following:

Inspect Hubs

    (a) Strip the protective coating, visually inspect for fretting 
wear, fluorescent magnetic particle inspect (FMPI), reidentify and 
replate HPC front hubs and the stage 8-9 spacers and replace if 
necessary in accordance with the accomplishment instructions of 
Pratt & Whitney Alert Service Bulletin (ASB) JT8D A6430, dated 
September 5, 2002, as follows:
    (1) For HPC front hubs with fewer than 17,000 total cycles-in-
service (CIS) on the effective date of this AD, inspect at the first 
shop visit after accumulating 9,000 total CIS or before accumulating 
18,000 total CIS, whichever occurs first.
    (2) For HPC front hubs with greater than or equal to 17,000 
total CIS but less than 19,000 total CIS on the effective date of 
this AD, inspect at the next shop visit, not to exceed 1,000 CIS 
from the effective date of this AD or 19,500 total CIS, whichever 
occurs first.
    (3) For HPC front hubs with greater than or equal to 19,000 
total CIS on the effective date of this AD, inspect within 500 CIS 
from the effective date of this AD.

Repetitive-Inspections

    (b) Thereafter, strip the protective coating, visually inspect 
for fretting wear, FMPI and replate HPC front hubs and replace if 
necessary in accordance with the accomplishment instructions of 
Pratt & Whitney Alert Service Bulletin (ASB) JT8D A6430, dated 
September 5, 2002, at intervals not to exceed 6,500 CIS since the 
last inspection

Optional Terminating Action

    (c) Installation of a Nickel-Cadmium plated HPC front hub that 
has never operated with PWA-110 coating in the interface between the 
HPC front hub and the stage 8-9 spacer and a Nickel-Cadmium or 
Electroless Nickel plated spacer is an optional terminating action 
for the inspections of paragraphs (a) and (b) of this AD.

Definitions

    (d) For the purposes of this AD, a shop visit is defined as an 
engine removal, where engine maintenance entails separation of pairs 
of major 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

    (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 (ECO). 
Operators must submit their requests 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

    (f) 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 airplane to a location where 
the requirements of this AD can be done.

    Issued in Burlington, Massachusetts, on September 10, 2002.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 02-23776 Filed 9-18-02; 8:45 am]
BILLING CODE 4910-13-P