
[Federal Register Volume 79, Number 247 (Wednesday, December 24, 2014)]
[Rules and Regulations]
[Pages 77384-77385]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-30283]


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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; 
Amendment 39-18017; AD 2014-23-01]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Division Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; correction.

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SUMMARY: The FAA is correcting an airworthiness directive (AD) that 
published in the Federal Register. That AD applies to all Pratt & 
Whitney Division (PW) PW4074, PW4074D, PW4077, PW4077D, PW4084D, 
PW4090, and PW4090-3 turbofan engine models with certain second-stage 
high-pressure turbine (HPT) air seals installed. The time required to 
perform the initial eddy current inspection (ECI) in the Compliance 
section is incorrect. This document corrects that error. In all other 
respects, the original document remains the same.

DATES: This final rule is effective on December 26, 2014. The effective 
date of AD 2014-23-01, Amendment 39-18017 (79 FR 69369, November 21, 
2014) remains December 26, 2014.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of September 
17, 2013 (78 FR 49111, August 13, 2013).

ADDRESSES: 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 AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (phone: 800-647-5527) is Document Management Facility, 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Jo-Ann Theriault, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-7105; 
fax: 781-238-7199; email: jo-ann.theriault@faa.gov.

SUPPLEMENTARY INFORMATION: AD 2014-23-01, Amendment 39-18017 (79 FR 
69369, November 21, 2014), requires initial and repetitive inspections 
for cracks in second-stage HPT air seals, the removal of the mating 
hardware if the second-stage HPT air seal is found with a through-
crack, and a mandatory terminating action for all PW PW4074, PW4074D, 
PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engine models 
with certain second-stage HPT air seals installed.
    As published, the time required to perform the initial ECI in the 
Compliance section is incorrect. AD 2014-23-01, paragraph (e)(2)(i), 
requires an initial ECI for cracks within 1,000 cycles-in-service after 
September 17, 2013, or before further flight, whichever occurs later. 
That compliance time is more restrictive than intended and will likely 
ground airplanes. The intent was to require an initial ECI for cracks 
before reaching 2,200 cycles since new, or within 1,000 cycles-in-
service after September 17, 2013, or before further flight, whichever 
occurs later.
    No other part of the preamble or regulatory information has been 
changed.
    The effective date of AD 2014-23-01 remains December 26, 2014.

Correction of Regulatory Text


Sec.  39.13  [Corrected]

0
2. The FAA amends Sec.  39.13 by removing Airworthiness Directive (AD) 
2013-15-09, Amendment 39-17525 (78 FR 49111, August 13, 2013), and 
adding the following new AD:

2014-23-01 Pratt & Whitney Division: Amendment 39-18017; Docket No. 
FAA-2013-0072; Directorate Identifier 2013-NE-04-AD.

[[Page 77385]]

(a) Effective Date

    This AD is effective December 26, 2014.

(b) Affected ADs

    This AD supersedes AD 2013-15-09, Amendment 39-17525 (78 FR 
49111, August 13, 2013).

(c) Applicability

    This AD applies to all Pratt & Whitney Division (PW) PW4074, 
PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan 
engine models with second-stage high-pressure turbine (HPT) air 
seal, part number (P/N) 54L041, 50L960, or 50L976, installed.

(d) Unsafe Condition

    This AD was prompted by additional reports of cracking in the 
second-stage HPT air seal. We are issuing this AD to prevent failure 
of the second-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) At the next piece-part exposure after the effective date of 
this AD, do the following:
    (i) Remove from service second-stage HPT air seals, P/Ns 50L960, 
50L976, and 54L041.
    (ii) Perform a fluorescent-penetrant inspection (FPI) of the 
second-stage HPT air seal, P/N 54L041, for a through-crack in the 
front forward fillet radius.
    (iii) If a through-crack in the front forward fillet radius is 
found, remove the first-stage HPT hub, second-stage HPT hub, and 
second-stage HPT blade retaining plate from service. Do not 
reinstall the first-stage HPT hub, second-stage HPT hub, or second-
stage HPT blade retaining plate into any engine.
    (2) For engines with second-stage HPT air seals, P/N 54L041, 
installed, perform initial and repetitive inspections for cracks on-
wing until the part is removed from the engine as follows:
    (i) Perform an initial eddy current inspection (ECI) for cracks 
before reaching 2,200 cycles since new, within 1,000 cycles-in-
service after September 17, 2013, or before further flight, 
whichever occurs later.
    (ii) Thereafter, repeat the ECI every 1,200 cycles since last 
inspection, or fewer, depending on the results of the inspection.
    (iii) Use section 4.0 of the appendix of PW Alert Service 
Bulletin (ASB) No. PW4G-112-A72-330, Revision 2, dated July 11, 
2013, to perform the inspection and use paragraph 8 of the 
Accomplishment Instructions of PW ASB No. PW4G-112-A72-330, Revision 
2, dated July 11, 2013, to disposition the results of the 
inspection.

(f) Installation Prohibition

    (1) After the effective date of this AD, do not install any 
second-stage HPT air seal, P/N 54L041, P/N 50L960, or P/N 50L976, 
into any engine.
    (2) After the effective date of this AD, do not install any 
spare first-stage HPT hub, second-stage HPT hub, or second-stage HPT 
blade retaining plate that was previously mated in service to a 
second-stage HPT air seal, P/N 54L041, that was found to have a 
through-crack in the front forward fillet radius, into any engine.

(g) Definitions

    For the purpose of this AD:
    (1) Piece-part exposure is when the second-stage HPT air seal is 
removed from the engine and fully disassembled.
    (2) A through-crack is a crack that has propagated through the 
thickness of the part and can be seen on both the inner diameter and 
outer diameter of the front forward fillet radius.

(h) Credit for Previous Actions

    (1) If you performed an ECI of the second-stage HPT air seal 
before the effective date of this AD, using PW ASB No. PW4G-112-A72-
330, Revision 1, dated February 14, 2013, or an earlier version, you 
have met the requirements of paragraph (e)(2)(i) of this AD.
    (2) If you performed an in-shop FPI of the second-stage HPT air 
seal before the effective date of this AD, you have met the 
requirements of paragraph (e)(2)(i) of this AD.

(i) 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. You may email your request to: ANE-AD-AMOC@faa.gov.

(j) Related Information

    (1) For more information about this AD, contact Jo-Ann 
Theriault, Aerospace Engineer, Engine Certification Office, FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA 01803; phone: 781-238-7105; fax: 781-238-7199; email: 
jo-ann.theriault@faa.gov.
    (2) PW Service Bulletin (SB) No. PW4G-112-72-332, Revision 3, 
dated June 25, 2014, which is not incorporated by reference in this 
AD, can be obtained from PW, using the contact information in 
paragraph (k)(3) of this AD. This SB provides guidance on how to 
replace the second-stage HPT air seal with an air seal that is more 
resistant to low cycle fatigue cracks.

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (3) The following service information was approved for IBR on 
September 17, 2013 (78 FR 49111, August 13, 2013).
    (i) Pratt & Whitney (PW) Alert Service Bulletin No. PW4G-112-
A72-330, Revision 2, dated July 11, 2013.
    (ii) Reserved.
    (4) For PW service information identified in this AD, contact 
Pratt & Whitney Division, 400 Main St., East Hartford, CT 06108; 
phone: 860-565-8770; fax: 860-565-4503.
    (5) You may view this service information at 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.
    (6) You may view this service information at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to: 
http://www.archives.gov/federal-register/cfr/ibr-locations.html.


    Issued in Burlington, Massachusetts, on December 22, 2014.
Colleen M. D'Alessandro,
Assistant Directorate Manager, Engine and Propeller Directorate, 
Aircraft Certification Service.
[FR Doc. 2014-30283 Filed 12-23-14; 8:45 am]
BILLING CODE 4910-13-P


