Document ID: FAA-2010-0514-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Pratt and Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines
Posted Date: 2010-05-19T04:00Z

[Federal Register: May 19, 2010 (Volume 75, Number 96)]
[Proposed Rules]               
[Page 27972-27973]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19my10-18]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0514; Directorate Identifier 2010-NE-02-AD]
RIN 2120-AA64

 
Airworthiness Directives; Pratt & Whitney JT8D-9, -9A, -11, -15, 
-17, and -17R Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Pratt & Whitney (PW) JT8D-9, -9A, -11, -15, -17, and -17R turbofan 
engines. This proposed AD would require overhauling fan blade leading 
edges at the first shop visit after 4,000 cycles-in-service (CIS) since 
the last total fan blade overhaul was performed. This proposed AD 
results from reports of failed fan blades. We are proposing this AD to 
prevent high-cycle fatigue cracking at the blade root, which could 
result in uncontained failures of first stage fan blades and damage to 
the airplane.

DATES: We must receive any comments on this proposed AD by July 19, 
2010.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     Federal eRulemaking Portal: Go to http://
www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.
    Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108; 
telephone (860) 565-7700; fax (860) 565-1605, for a copy of the service 
information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: James Gray, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
james.gray@faa.gov; telephone (781) 238-7742; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2010-0514; Directorate 
Identifier 2010-NE-02-AD'' in the subject line of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of the proposed AD. We will consider 
all comments received by the closing date and may amend the proposed AD 
in light of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, the name of the individual who 
sent the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78).

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

Discussion

    We have received reports of 16 first stage fan blade root 
fractures, two of which resulted in penetration of the cowl and minor 
damage to the fuselage. Engineering investigation has determined that 
increased vibratory stress in the root and airfoil from eroded and 
blunt leading edges caused the fan blade failures. The primary cause of 
leading edge erosion is the operating environment, particularly rain 
and sand. The aerodynamic performance of the blade is diminished and 
vibratory stress in the airfoil and root is increased. This condition, 
if not corrected, could result in uncontained failures of first stage 
fan blades and damage to the airplane.

Relevant Service Information

    We have reviewed and approved the technical contents of PW JT8D 
Maintenance Advisory Notice MAN-JT8D-2-06, dated November 20, 2006, 
that describes procedures for overhauling the first stage fan blades at 
every shop visit where pairs of major mating flanges are separated.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. We are proposing this AD, which would require 
overhauling the total set of stage 1 fan blades at:
     The first shop visit after 4,000 CIS since the last total 
stage 1 fan blade overhaul or
     The next shop visit after the effective date of this 
proposed AD if the CIS since the last total stage 1 fan blade overhaul 
is unknown and
     Thereafter, at the next shop visit after 4,000 CIS since 
the last total stage fan blade overhaul.
    The proposed AD would require you to use the service information 
described previously to perform these actions.

Costs of Compliance

    We estimate that this proposed AD would affect 1,527 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 63 work-hours per engine to perform the proposed actions, 
and that the average labor rate is $85 per work-hour. There would be no 
required parts. Based on these figures, we estimate the total cost of 
the proposed AD to U.S. operators to be $8,177,085.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more

[[Page 27973]]

detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed AD:
    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. Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Pratt & Whitney: Docket No. FAA-2010-0514; Directorate Identifier 
2010-NE-02-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by July 19, 
2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Pratt & Whitney (PW) JT8D-9, -9A, -11, -
15, -17, and -17R turbofan engines. These engines are installed on, 
but not limited to, Boeing 727 series, Boeing 737-200 series and 
McDonnell Douglas DC-9 airplanes.

Unsafe Condition

    (d) This AD results from reports of failed fan blades. We are 
issuing this AD to prevent high-cycle fatigue cracking at the blade 
root, which could result in uncontained failures of first stage fan 
blades and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Initial Overhaul

    (f) For engines where the cycles-in-service (CIS) since last 
overhaul are known, overhaul the total set of stage 1 fan blades at 
the first shop visit after 4,000 CIS since the last total stage 1 
fan blade overhaul, or the next shop visit after the effective date 
of this AD, whichever occurs later. Guidance on performing a fan 
blade overhaul can be found in Pratt & Whitney JT8D Maintenance 
Advisory Notice, MAN-JT8D-2-06 and the Engine Manual Chapter/Section 
72-33-21, Inspection 00.
    (g) For engines where the CIS since last overhaul are unknown, 
overhaul the total set of stage 1 fan blades at the next shop visit 
after the effective date of this AD. Guidance on performing a fan 
blade overhaul can be found in Pratt & Whitney JT8D Maintenance 
Advisory Notice, MAN-JT8D-2-06 and the Engine Manual Chapter/Section 
72-33-21, Inspection 00.

Repetitive Overhaul

    (h) Thereafter, overhaul the total set of stage 1 fan blades at 
the first shop visit after 4,000 CIS since the last total stage 1 
fan blade overhaul. Guidance on performing a fan blade overhaul can 
be found in Pratt & Whitney JT8D Maintenance Advisory Notice, MAN-
JT8D-2-06 and the Engine Manual Chapter/Section 72-33-21, Inspection 
00.

Definitions

    (i) For the purpose of this AD, a shop visit is the induction of 
an engine into the shop for maintenance involving the separation of 
pairs of major mating engine flanges, except that the separation of 
engine flanges solely for the purposes of transporting the engine 
without subsequent engine maintenance does not constitute an engine 
shop visit.

Alternative Methods of Compliance

    (j) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (k) Contact James Gray, Aerospace Engineer, Engine Certification 
Office, FAA, Engine & Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: james.gray@faa.gov; 
telephone (781) 238-7742; fax (781) 238-7199, for more information 
about this AD.
    (l) Pratt & Whitney JT8D Maintenance Advisory Notice MAN-JT8D-2-
06, dated November 20, 2006, pertains to the subject of this AD. 
Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108; 
telephone (860) 565-7700; fax (860) 565-1605, for a copy of this 
service information.

    Issued in Burlington, Massachusetts, on May 13, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2010-11999 Filed 5-18-10; 8:45 am]
BILLING CODE 4910-13-P