
[Federal Register Volume 78, Number 52 (Monday, March 18, 2013)]
[Proposed Rules]
[Pages 16620-16622]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-06118]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0072; Directorate Identifier 2013-NE-04-AD]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Division Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
Pratt & Whitney Division (PW) turbofan engine models PW4074, PW4074D, 
PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 with a certain 2nd-stage 
high-pressure turbine (HPT) air seal part number (P/N) installed. This 
proposed AD was prompted by discovery of cracks in the 2nd-stage HPT 
air seals. This proposed AD would require, for those air seals that 
meet certain cycles since new (CSN) criteria, inspection and removal 
from service of HPT air seals that fail inspection. We are proposing 
this AD to prevent failure of the 2nd-stage HPT air seal, which could 
lead to an uncontained engine failure and damage to the airplane.

DATES: We must receive comments on this proposed AD by May 17, 2013.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.

[[Page 16621]]

     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Pratt & 
Whitney, 400 Main St., East Hartford, CT 06108; phone: 860-565-8770; 
fax: 860-565-4503. You may view this service information at the FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA. For information on the availability of this material at 
the FAA, call 781-238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
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 Office (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Ian Dargin, Aerospace Engineer, Engine 
& Propeller Directorate, FAA, 12 New England Executive Park, 
Burlington, MA 01803; phone: 781-238-7178; fax: 781-238-7199; email: 
ian.dargin@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2013-0072; 
Directorate Identifier 2013-NE-04-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because 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 we 
receive about this proposed AD.

Discussion

    We propose to adopt a new AD for all PW turbofan engine models 
PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 with 
2nd-stage HPT air seal, P/N 54L041, installed. This proposed AD was 
prompted by cracks in 2nd-stage HPT air seals discovered during 
fluorescent-penetrant inspection (FPI). This proposed AD would require, 
for HPT air seals that meet certain CSN criteria, either on-wing eddy 
current inspection (ECI) or in-shop FPI, and removal from service of 
any HPT air seal that fails inspection. We are proposing this AD to 
prevent failure of the 2nd-stage HPT air seal. This condition, if not 
corrected, could lead to an uncontained engine failure, and damage to 
the airplane.

Relevant Service Information

    We reviewed PW Alert Service Bulletin (ASB) PW4G-112-A72-330, 
Revision 1, dated February 26, 2013. The ASB describes procedures for 
inspecting the integrity of 2nd-stage HPT air seals and criteria for 
their removal from service and replacement.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously.

Interim Action

    We consider this proposed AD interim action. PW has not determined 
the root cause of the cracks discovered in 2nd-stage HPT air seals.

Costs of Compliance

    We estimate that this AD will affect 83 engines installed on 
airplanes of U.S. registry. We also estimate that it would take about 5 
hours to perform the inspection required by this proposed AD. The costs 
of an ECI and an FPI are assumed to be equal. The average labor rate is 
$85 per hour. Based on these figures, we estimate the total cost of the 
AD to U.S. operators will be $35,275.

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 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 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 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),
    (3) Will not affect intrastate aviation in Alaska to the extent 
that it justifies making a regulatory distinction, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

Pratt & Whitney Division: Docket No. FAA-2013-0072; Directorate 
Identifier 2013-NE-04-AD.

(a) Comments Due Date

    We must receive comments by May 17, 2013.

[[Page 16622]]

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Pratt & Whitney Division (PW) turbofan 
engine models PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and 
PW4090-3 with 2nd-stage high-pressure turbine (HPT) air seal, part 
number 54L041, installed.

(d) Unsafe Condition

    This AD was prompted by discovery of cracks in the 2nd-stage HPT 
air seals. We are issuing this AD to prevent failure of the 2nd-
stage HPT air seal, which could lead to uncontained engine failure 
and damage to the airplane.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) For 2nd-stage HPT air seals that have 1,200 or fewer cycles 
since new (CSN) on the effective date of this AD, perform an on-wing 
eddy current inspection (ECI) or in-shop fluorescent-penetrant 
inspection (FPI) for cracks within 2,200 CSN.
    (2) For 2nd-stage HPT air seals that have more than 1,200 CSN on 
the effective date of this AD, perform an on-wing ECI or in-shop FPI 
for cracks within 1,000 cycles after the effective date of this AD.
    (3) Thereafter, reinspect with either an on-wing ECI or in-shop 
FPI every 1,200 cycles since last inspection.
    (4) If you find a crack, remove the air seal from service before 
further flight.
    (5) Use paragraph 7 of the Accomplishment Instructions of PW 
Alert Service Bulletin (ASB) PW4G-112-A72-330, Revision 1, dated 
February 26, 2013, to do the on-wing ECI, except the reporting 
requirement of that step.

(f) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
for this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(g) Related Information

    (1) For more information about this AD, contact Ian Dargin, 
Aerospace Engineer, Engine & Propeller Directorate, FAA, 12 New 
England Executive Park, Burlington, MA 01803; phone: 781-238-7178; 
fax: 781-238-7199; email: ian.dargin@faa.gov.
    (2) Refer to PW ASB PW4G-112-A72-330, Revision 1, dated February 
26, 2013, for related information.
    (3) For service information identified in this AD, contact Pratt 
& Whitney, 400 Main St., East Hartford, CT 06108; phone: 860-565-
8770; fax: 860-565-4503. You may view this service information at 
the FAA, Engine & Propeller Directorate, 12 New England Executive 
Park, Burlington, MA. For information on the availability of this 
material at the FAA, call 781-238-7125.

    Issued in Burlington, Massachusetts, on March 4, 2013.
Colleen M. D'Alessandro,
Assistant Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2013-06118 Filed 3-15-13; 8:45 am]
BILLING CODE 4910-13-P


