Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

[Federal Register Volume 80, Number 207 (Tuesday, October 27, 2015)]
[Rules and Regulations]
[Pages 65614-65616]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-27184]


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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; 
Amendment 39-18307; AD 2015-22-03]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Division Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting 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 including models with a ``-3'' suffix with a 
low-pressure turbine (LPT) 4th stage inner air seal (IAS), part number 
(P/N) 51N038, installed. This AD was prompted by the discovery, during 
routine overhaul of the LPT, of cracks in the barrel section of the LPT 
4th stage IAS. This AD requires removal of the LPT 4th stage IAS, P/N 
51N038, according to a prescribed schedule. 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.

DATES: This AD is effective December 1, 2015.

ADDRESSES: 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. 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 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: 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: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to all 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 including models with a ``-
3'' suffix with an LPT 4th stage IAS, P/N 51N038, installed. The NPRM 
published in the Federal Register on June 1, 2015 (80 FR 30963). The 
NPRM was prompted by nine occasions of discovering, during routine 
overhaul of the LPT, cracks in the barrel section of the LPT 4th stage 
IAS. The NPRM proposed to require removal of the LPT 4th stage IAS, P/N 
51N038, according to a prescribed schedule. 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.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Support for the NPRM (80 FR 30963, June 1, 2015)

    The Boeing Company expressed support for the NPRM.

Request To Change Definitions

    United Airlines and Delta Airlines requested that the Definitions 
paragraph be changed. United Airlines requested we change the 
definition of LPT overhaul from ``maintenance which involves 
disassembly of the LPT rotor module'' to ``when the LPT module is 
disassembled sufficiently to gain access

[[Page 65615]]

to the LPT 4th stage rotor assembly (disk/blade/seal).'' Delta Airlines 
requested we change the definition of an LPT overhaul to ``when all 
disks in the rotor are removed from the engine and the blades are 
removed.''
    We agree that the definition of an LPT overhaul should be 
clarified. We changed the definition of an LPT overhaul to ``An LPT 
overhaul is defined as when all disks in the rotor are removed from the 
engine and the blades are removed.''

Request To Change Applicability

    Delta Airlines requested changing the applicability to include 
models with any dash number suffix.
    We agree with the intent of this request. We changed the Summary, 
Discussion, and Applicability sections by adding ``. . . including 
models with a ``-3'' suffix . . .'' following the listed engine models 
as required.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously. We determined that these 
changes will not increase the economic burden on any operator or 
increase the scope of this AD.

Costs of Compliance

    We estimate that this AD affects 72 engines installed on airplanes 
of U.S. registry. We also estimate that 9 of the engines will require 
replacement parts during shop visit, the pro-rated cost of these parts 
cost will be $23,805 per engine, and compliance with this AD will 
require about 49 hours of labor per engine. The average labor rate is 
$85 per hour. We also estimate that 63 of the engines will require 
replacement parts during LPT overhaul, the pro-rated replacement parts 
cost for these parts is $43,545 per engine, and that these 63 engines 
will 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 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

    This AD will not have federalism implications under Executive Order 
13132. This AD will 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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under 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.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 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):

2015-22-03 Pratt & Whitney Division: Amendment 39-18307; Docket No. 
FAA-2015-0787; Directorate Identifier 2015-NE-10-AD.

(a) Effective Date

    This AD is effective December 1, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to:
    (1) All Pratt & Whitney Division 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 including models with a ``-3'' 
suffix 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 LPT 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.

(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 when all disks in the rotor 
are removed from the engine and the blades are removed.
    (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: [email protected].

[[Page 65616]]

(i) Related Information

    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: 
[email protected].

(j) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on October 21, 2015.
Colleen M. D'Alessandro,
Directorate Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2015-27184 Filed 10-26-15; 8:45 am]
BILLING CODE 4910-13-P

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