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[Federal Register Volume 80, Number 104 (Monday, June 1, 2015)]
[Proposed Rules]
[Pages 30963-30965]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-12663]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-0787; Directorate Identifier 2015-NE-10-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) PW4164, PW4168, PW4168A, PW4164C, 
PW4164C/B, PW4164-1D, PW4168-1D, PW4168A-1D, PW4170, PW4164C-1D, 
PW4164C/B-1D, PW4050, PW4052, PW4056, PW4060, PW4060A, PW4060C, PW4062, 
PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, PW4460, PW4462, and 
PW4650 turbofan engines with a low-pressure turbine (LPT) 4th stage 
inner air seal (IAS), P/N 51N038, installed. This proposed AD was 
prompted by the discovery, during routine overhaul of the LPT, of 
cracks in the barrel section of the 4th stage IAS. This proposed AD 
would require removal of the LPT 4th stage IAS, P/N 51N038, according 
to a prescribed schedule. We are proposing this AD to prevent failure 
of the LPT 4th stage IAS, which could lead to an uncontained IAS 
release, damage to the engine, and damage to the airplane.

DATES: We must receive comments on this proposed AD by July 31, 2015.

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.
     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 proposed AD, contact 
Pratt & Whitney Division, 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 by searching for and locating Docket No. FAA-2015-
0787; 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: Katheryn Malatek, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-7747; 
fax: 781-238-7199; email: katheryn.malatek@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-2015-0787; 
Directorate Identifier 2015-NE-10-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 PW4164, PW4168, PW4168A, 
PW4164C, PW4164C/B, PW4164-1D, PW4168-1D, PW4168A-1D, PW4170,

[[Page 30964]]

PW4164C-1D, PW4164C/B-1D, PW4050, PW4052, PW4056, PW4060, PW4060A, 
PW4060C, PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, 
PW4460, PW4462, and PW4650 turbofan engines with an LPT 4th IAS, P/N 
51N038, installed. This proposed AD was prompted by 9 occasions of 
discovering, during routine overhaul of the LPT, cracks in the barrel 
section of the 4th stage IAS. This condition, if not corrected, could 
result in uncontained IAS release, damage to the engine, and damage to 
the aircraft. This proposed AD would require removal of the 4th stage 
IAS, P/N 51N038, according to a prescribed schedule. We are proposing 
this AD to prevent failure of the LPT 4th stage IAS, which could lead 
to an uncontained IAS release, damage to the engine, and damage to the 
airplane.

Related Service Information

    We reviewed PW Alert Service Bulletin (ASB) No. PW4G-100-A72-254, 
dated December 12, 2014. The ASB describes procedures and timetables 
for removing the LPT 4th stage IAS. This service information is 
reasonably available; see ADDRESSES for ways to access this service 
information.

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 removal of the LPT 4th stage IAS, P/
N 51N038, according to a prescribed schedule.

Differences Between This Proposed AD and the Service Information

    PW ASB No. PW4G-100-A72-254, dated December 12, 2014, applies to 
certain PW4000 engine models. This proposed AD applies to the 7 engine 
models listed in the ASB, plus 4 additional PW4000 engine models 
certificated for use in the U.S. for which the affected LPT 4th IAS, P/
N 51N038, is eligible for installation. These 11 engine models are 
listed in paragraph (c)(1) of this AD.
    We further expanded the applicability to cover 16 additional engine 
models, listed in paragraph (c)(2) of this AD, which are prohibited 
from installing P/N 51N038, if that part was ever installed on any 
engine listed in paragraph (c)(1) of this AD. The unsafe condition 
described in paragraph (d) of this AD could exist in the part if it was 
ever operated in any engine listed in paragraph (c)(1) of this AD.

Costs of Compliance

    We estimate that this proposed AD affects 72 engines installed on 
airplanes of U.S. registry. We also estimate that 9 of the engines 
would require replacement parts during shop visit, and that for these 
engines the pro-rated replacement parts cost would be $23,805 per 
engine, and compliance with this proposed AD would require about 49 
hours of labor per engine. The average labor rate is $85 per hour. We 
also estimate that 63 of the engines would require replacement parts 
during LPT overhaul, that the prorated replacement parts cost for these 
63 engines would be $43,545 per engine, and that compliance with this 
proposed AD for these 63 engines would require 0 additional hours of 
labor per engine since the parts are already exposed during LPT 
overhaul. Based on these figures, we estimate the cost of this proposed 
AD on U.S. operators to be $2,995,065.

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-2015-0787; Directorate 
Identifier 2015-NE-10-AD.

(a) Comments Due Date

    We must receive comments by July 31, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to:
    (1) All Pratt & Whitney Division (PW) PW4164, PW4168, PW4168A, 
PW4164C, PW4164C/B, PW4164-1D, PW4168-1D, PW4168A-1D, PW4170, 
PW4164C-1D, and PW4164C/B-1D turbofan engines with a low-pressure 
turbine (LPT) 4th stage inner air seal (IAS), part number (P/N) 
51N038, installed.
    (2) All PW4050, PW4052, PW4056, PW4060, PW4060A, PW4060C, 
PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, PW4460, 
PW4462, and PW4650 turbofan engines with an LPT 4th stage IAS, P/N 
51N038, installed.

(d) Unsafe Condition

    This AD was prompted by the discovery, during routine overhaul 
of the LPT, of cracks in the barrel section of the 4th stage IAS 
which could, if not corrected, result in uncontained IAS release, 
damage to the engine, and damage to the aircraft. We are issuing 
this AD to prevent failure of the LPT 4th stage IAS, which could 
lead to an uncontained IAS release, damage to the engine, and damage 
to the airplane.

[[Page 30965]]

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done. For the engines listed in paragraph (c)(1) of 
this AD:
    (1) At each LPT overhaul after the effective date of this AD 
remove from service the LPT 4th stage IAS, P/N 51N038.
    (2) At each engine shop visit after the effective date of this 
AD, remove from service the LPT 4th stage IAS, P/N 51N038, if it has 
more than 10,900 cycles since new.

(f) Installation prohibition

    (1) Do not install any LPT 4th stage IAS, P/N 51N038, with more 
than 0 flight cycles on any engine listed in paragraph (c)(1) of 
this AD.
    (2) Do not install on any engine listed in paragraphs (c)(2) of 
this AD, any LPT 4th stage IAS, P/N 51N038, which was previously 
installed on any engine listed in paragraph (c)(1) of this AD.

(g) Definitions

    For the purposes of this AD:
    (1) An LPT overhaul is defined as maintenance which involves 
disassembly of the LPT rotor module.
    (2) An ``engine shop visit'' is the induction of an engine into 
the shop for maintenance involving the separation of pairs of major 
mating engine flanges (lettered flanges). The separation of engine 
flanges solely for the purpose of transportation without subsequent 
engine maintenance does not constitute an engine shop visit.

(h) 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.

(i) Related Information

    (1) For more information about this AD, contact Katheryn 
Malatek, Aerospace Engineer, Engine Certification Office, FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA 01803; phone: 781-238-7747; fax: 781-238-7199; email: 
katheryn.malatek@faa.gov.
    (2) PW Alert Service Bulletin No. PW4G-100-A72-254, dated 
December 12, 2014, can be obtained from PW using the contact 
information in paragraph (i)(3) of this AD.
    (3) For 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.
    (4) 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 May 13, 2015.
Colleen M. D'Alessandro,
Assistant Directorate Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2015-12663 Filed 5-29-15; 8:45 am]
 BILLING CODE 4910-13-P
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