[Federal Register Volume 63, Number 231 (Wednesday, December 2, 1998)]
[Proposed Rules]
[Pages 66500-66502]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-32048]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-ANE-02]
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 supersedure of an existing 
airworthiness directive (AD), applicable to Pratt & Whitney JT8D-200 
series turbofan engines, that currently requires periodic inspection of 
fan blades for locked rotors and foreign object damage (FOD), unlocking 
of shrouds if necessary, lubrication of fan blade shrouds, and 
dimensional restoration of the fan blade leading edge. In addition, 
that AD requires installation of improved design fan blades as 
terminating action for the inspections. This action would reduce the 
lubrication interval, and require removal of rotors that experience 
repeat lockups within 225 cycles in service. This proposal is prompted 
by reports of 7 fan blade failures since publication of the current AD. 
The actions specified by the proposed AD are intended to prevent fan 
blade failure, which can result in damage to the aircraft.

DATES: Comments must be received by February 1, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 96-ANE-02, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[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 fan blade failure, which can result in damage to the 
aircraft. 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: Peter White, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7128, 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 96-ANE-02.'' 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. 96-ANE-02, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    On November 7, 1996, the Federal Aviation Administration (FAA) 
issued airworthiness directive AD 96-23-15, Amendment 39-9821 (61 FR 
63706, December 2, 1996), applicable to Pratt & Whitney (PW) JT8D-200 
series turbofan

[[Page 66501]]

engines, to require periodic inspection of fan blades for locked rotors 
and foreign object damage (FOD), unlocking of shrouds if necessary, 
lubrication of fan blade shrouds, and dimensional restoration of the 
fan blade leading edge. In addition, that AD requires installation of 
improved design fan blades as terminating action for the inspections. 
That action was prompted by the introduction into service of improved 
design fan blades. That condition, if not corrected, could result in 
fan blade failure, which can result in damage to the aircraft.
    Since the issuance of that AD, the FAA has received reports of 7 
additional fan blade failures on engines that had been inspected in 
accordance with the current AD. The fan blades are failing as a result 
of high cycle fatigue. Contributing factors are foreign object damage 
(FOD), leading edge erosion, manufacturing discrepancies, and locked 
fan shrouds. These fan blade failures indicate that the currently 
mandated fleet management plan is insufficient.
    The FAA has reviewed and approved the technical contents of PW 
Alert Service Bulletin (ASB) No. A6241, Revision 2, dated June 29, 
1998, that reduces the lubrication interval, and requires removal of 
rotors that experience repeat lockups within 225 cycles in service 
(CIS).
    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 96-23-15 to reduce the lubrication 
interval, and require removal of rotors that experience repeat lockups 
within 225 cycles in service.
    There are approximately 2,650 engines of the affected design in the 
worldwide fleet. The FAA estimates that 960 engines installed on 
aircraft of U.S. registry would be affected by this proposed AD, that 
it would take no additional work hours to perform these inspections 
except at a shorter lubrication interval. Rework costs for the fan 
blades are $275 per blade, of which approximately $140 per blade is 
attributable to this AD action. With the manufacturer's rebate of $50 
per blade, the total cost to industry of reworking these blades is 
$2,750 per engine. The manufacturer estimates that it will take 19 work 
hours per engine to remove and reinstall the blades. Using labor costs 
of $60 per hour, the labor costs to remove and reinstall the blades are 
$1,140 per engine. Hence, the increased costs generated by this 
proposed AD on U.S. operators is estimated to be $3,890 per engine, or 
$3,734,400 to retrofit the remaining 960 engines.
    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 removing amendment 39-9821 (61 FR 
63706, December 2, 1998) and by adding a new airworthiness directive to 
read as follows:

Pratt & Whitney: Docket No. 96-ANE-02. Supersedes AD 96-23-15, 
Amendment 39-9821.

    Applicability: Pratt & Whitney (PW) Models JT8D-209, -217, -
217A, -217C, and -219 turbofan engines that have not incorporated PW 
Service Bulletin (SB) No. 6193, dated October 31, 1994, or with fan 
blade, Part Numbers (P/N's) 798821, 798821-001, 808121, 808121-001, 
809221, 811821, 851121, 851121-001, 5000021-02, 5000021-022, and 
5000021-032 installed. These engines are installed on but not 
limited to McDonnell Douglas MD-80 series aircraft.

    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 fan blade failure, which can result in damage to the 
aircraft, accomplish the following:
    (a) Inspect fan blades and shrouds, unlock fan blade shrouds, 
lubricate fan blade shrouds, restore leading edge dimensions, and 
modify or install improved design fan blades in accordance with the 
schedule and procedures described in Parts 1, 2, and 3 of the 
Accomplishment Instructions of PW Alert Service Bulletin (ASB) No. 
A6241, Revision 2, dated June 29, 1998.
    (b) Modification of fan blades to the improved design 
configuration or installation of improved design fan blades in 
accordance with Part 3 of the Accomplishment Instructions of PW ASB 
No. A6241, Revision 2, dated June 29, 1998, constitutes terminating 
action to the inspections and maintenance actions described in 
paragraph (a) of this AD.
    (c) For the purpose of this AD, the accomplishment effective 
date to be used for determination of compliance intervals, as 
required by Section 2 of PW ASB No. A6241, Revision 2, dated June 
29, 1998, is defined as the effective date of this AD.
    (d) For the purpose of this AD, ``repair'' as specified in Part 
3, Paragraph A.(1)(b) of the Accomplishment Instructions of PW ASB 
No. A6241, Revision 2, dated June 29, 1998 is defined as the 
refurbishment of fan blades in accordance with Part 3, Paragraph C 
of the Accomplishment Instructions of PW ASB No. A6241, Revision 2, 
dated June 29, 1998.
    (e) Alternative methods of compliance that have been approved 
for AD 95-12-19 are applicable for this AD and additional approval 
is not required.
    (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. The 
request should be forwarded 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 method of compliance with this AD, if any, may be 
obtained from the 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

[[Page 66502]]

a location where the requirements of this AD can be accomplished.

    Issued in Burlington, Massachusetts, on November 24, 1998.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 98-32048 Filed 12-1-98; 8:45 am]
BILLING CODE 4910-13-P