[Federal Register Volume 61, Number 161 (Monday, August 19, 1996)]
[Rules and Regulations]
[Pages 42781-42782]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-21033]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-ANE-19; Amendment 39-9714; AD 96-15-06]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT8D-200 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule, request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 96-15-06 that was sent previously 
to all known U.S. owners and operators of Pratt & Whitney (PW) JT8D-200 
series turbofan engines by individual letters. This AD requires, prior 
to further flight, removal from service all affected fan hubs, 
identified by serial number, and replacement with serviceable parts. 
This amendment is prompted by a report of an accident involving an 
uncontained failure of a stage 1 fan hub. The actions specified by this 
AD are intended to prevent the initiation and propagation of a fatigue 
crack, fracture of the fan hub, uncontained engine failure, and damage 
to the aircraft.

DATES: Effective September 3, 1996, to all persons except those persons 
to whom it was made immediately effective by priority letter AD 96-15-
06, issued on July 16, 1996, which contained the requirements of this 
amendment.
    Comments for inclusion in the Rules Docket must be received on or 
before October 18, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 96-ANE-19, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be 
submitted to the Rules Docket by using the following Internet address: 
``[email protected]''. All comments must contain the 
Docket No. in the subject line of the comment.

FOR FURTHER INFORMATION CONTACT: Robert E. Guyotte, Manager, Engine 
Certification Branch, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (617) 238-
7142, fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: On July 16, 1996, the Federal Aviation 
Administration (FAA) issued priority letter airworthiness directive 
(AD) 96-15-06, applicable to Pratt & Whitney (PW) JT8D-200 series 
engines, which requires, prior to further flight, removal from service 
all affected fan hubs, identified by serial number, and replacement 
with serviceable parts. That action was prompted by a report of an 
accident involving an uncontained failure of a stage 1 fan hub. A fan 
hub failure poses a serious threat to safety of flight due to the 
possibility of high energy engine fragments penetrating the aircraft 
fuselage. The reported fan hub failure resulted from a fatigue crack 
that originated in a tie bolt hole. The fatigue crack initiated from 
mechanical surface damage produced during machining of the tie bolt 
holes, and propagated in a low cycle fatigue mode due to normal engine 
start-stop cycles. The manufacturing records indicate that a surface 
anomaly was observed in a tie bolt hole during the Blue Etch Anodize 
inspection which was determined to be acceptable. The manufacturing 
records indicate that six other hubs with similar anomalies in the tie 
bolt holes were installed on engines in revenue service. The FAA has 
determined that all hubs that exhibited surface anomalies during 
inspection of the type observed on the accident hub are not acceptable 
and must be removed from service, and replaced with a serviceable part 
prior to further flight. This condition, if not corrected, could result 
in the initiation and propagation of a fatigue crack, fracture of the 
fan hub, uncontained engine failure, and damage to the aircraft.
    The FAA is continuing the investigation and based on investigative 
findings, further rulemaking action may be required.
    Since the unsafe condition described is likely to exist or develop 
on other engines of the same type design, the FAA issued priority 
letter AD 96-15-06 to prevent fracture of the fan hub, uncontained 
engine failure, and damage to the aircraft. The AD requires, prior to 
further flight, removal from service all affected fan hubs, Part Number 
(P/N) 5000501-01, identified by any of the following Serial Numbers: 
T50693, T50823, T50827, R32926, R32960, P66756, and replacement with 
serviceable parts. The FAA determined this compliance time based on the 
potential severity of the aircraft hazard in the event of a fan hub 
failure, in conjunction with evidence of tie bolt hole surface 
anomalies during manufacturing inspection.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual letters 
issued on July 16, 1996, to all known U.S. owners and operators of PW 
JT8D-200 series turbofan engines. These conditions still exist, and the 
AD is hereby published in the Federal Register as an amendment to 
Section 39.13 of part 39 of the Federal Aviation Regulations (14 CFR 
part 39) to make it effective to all persons.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD 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

[[Page 42782]]

statement is made: ``Comments to Docket Number 96-ANE-19.'' The 
postcard will be date stamped and returned to the commenter.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, 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, 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 USC 106(g), 40113, 44701.


Sec. 39.13   [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

96-15-06 Pratt & Whitney: Amendment 39-9714. Docket 96-ANE-19.

    Applicability: Pratt & Whitney (PW) JT8D-200 series turbofan 
engines incorporating affected first stage fan hubs, Part Number (P/
N) 5000501-01, identified by any of the following Serial Numbers: 
T50693, T50823, T50827, R32926, R32960, P66756.
    These engines are installed on but not limited to McDonnell 
Douglas MD-80 series aircraft

    Note: 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 (b) 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 the initiation and propagation of a fatigue crack, 
fracture of the fan hub, uncontained engine failure, and damage to 
the aircraft, accomplish the following:
    (a) Prior to further flight, remove from service all affected 
first stage fan hubs, P/N 5000501-01, identified by Serial Numbers 
listed in the applicability paragraph of this AD, and replace with 
serviceable parts.
    (b) An alternative method of compliance or adjustment of 
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: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Engine Certification Office.

    (c) This amendment becomes effective September 3, 1996, to all 
persons except those persons to whom it was made immediately 
effective by priority letter AD 96-15-06, issued July 16, 1996, 
which contained the requirements of this amendment.

    Issued in Burlington, Massachusetts, on August 7, 1996.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 96-21033 Filed 8-16-96; 8:45 am]
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