Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

[Federal Register Volume 77, Number 57 (Friday, March 23, 2012)]
[Rules and Regulations]
[Pages 16921-16923]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-6996]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-1194; Directorate Identifier 2011-NE-36-AD; 
Amendment 39-16999; AD 2012-06-18]
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 PW4050, PW4052, PW4056, PW4060, PW4060A, PW4060C, 
PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, PW4460, 
PW4462, and PW4650 turbofan engines, including models with any dash 
number suffix. This AD was prompted by reports of five engine in-flight 
shutdowns and seven unplanned engine removals. This AD requires 
inspections, cleaning, and engine modifications to address coking in 
the No. 4 bearing compartment and in the oil pressure and scavenge 
tubes. We are issuing this AD to prevent an engine fire, a fractured 
fan drive shaft, and damage to the airplane.

DATES: This AD is effective April 27, 2012.

ADDRESSES: 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 review copies of the referenced 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 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: James Gray, Aerospace Engineer, Engine 
& Propeller Directorate, FAA, 12 New England Executive Park, 
Burlington, MA 01803; phone: 781-238-7742; fax: 781-238-7199; email: 
[email protected].

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM published in the Federal Register on November 23, 2011 (76 FR 
72353). That NPRM proposed to require inspections, cleaning, and engine 
modifications to address coking in the No. 4 bearing compartment and 
oil pressure and scavenge tubes.

[[Page 16922]]

Comments

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

Request To Not Call Out Specific Instructions

    Delta Airlines requested that we do not call out specific 
instructions to inspect, clean, and install the modifications, because 
operators have developed their own maintenance practices that are 
adequate, but may not align 100% with the Service Bulletin (SB) 
instructions.
    We agree. We changed the AD to not incorporate by reference the 
SBs, and to list them only as related information, without calling out 
any specific revision numbers of them.

Request To Recognize Compliance by Accomplishing SBs Before the 
Effective Date of the AD

    Federal Express, United Parcel Service, and United Airlines 
requested that we recognize that their compliance by accomplishing 
earlier versions of Pratt & Whitney SB No. PW4ENG 72-472 and SB No. 
PW4ENG 79-76 before the effective date of the AD is terminating action 
to the AD. The commenters stated that many engines have already had the 
modifications accomplished but to earlier versions of the SBs.
    We agree. Because we no longer incorporate the SBs by reference, if 
the requirements of the AD have already been done either by the current 
revision or an earlier revision of SB No. PW4ENG 72-472, SB No. PW4ENG 
79-76, and Alert SB No. A72-436, or other methods, techniques, or 
practices acceptable to the Administrator, then no further action is 
required. We have also changed the applicability to limit the AD to 
only those engines that have not already made the modifications.

Update to the List of Affected Engine Models

    Since we issued the NPRM (76 FR 72353, November 23, 2011), we 
determined that we need to update the list of affected engine models, 
to reflect the models listed in the title block of the type certificate 
data sheet. Engine models PW4060C, PW4062, PW4062A, PW4650, and PW4160 
have been added in this AD. The affected engine models in operation, as 
listed in the NPRM, have not changed in this AD.

Conclusion

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

Costs of Compliance

    We estimate that this AD will affect 44 turbofan engines installed 
on airplanes of U.S. registry. We estimate that it will take 8 work-
hours per engine to perform an inspection and cleaning of the No. 4 
bearing compartment; 7 work-hours per engine to perform the 
modification to stop buildup of coking in the No. 4 bearing 
compartment; and 33.7 work-hours per engine to perform the rerouting of 
the No. 4 bearing pressure and scavenge tubes. The average labor rate 
is $85 per work-hour. Required parts will cost about $69,322 per 
engine. Based on these figures, we estimate the total cost of the AD to 
U.S. operators to be $3,232,306.

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, 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):

2012-06-18 Pratt & Whitney Division: Amendment 39-16999; Docket No. 
FAA-2011-1194; Directorate Identifier 2011-NE-36-AD.

(a) Effective Date

    This AD is effective April 27, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Pratt & Whitney PW4050, PW4052, PW4056, 
PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4152, PW4156, PW4156A, 
PW4158, PW4160, PW4460, PW4462, and PW4650 turbofan engines, 
including models with any dash number suffix, that have not 
incorporated Pratt & Whitney Alert Service Bulletin (ASB) No. 
PW4ENG-A72-436; Service Bulletin (SB) No. PW4ENG-79-76; and SB No. 
PW4ENG-72-472.

(d) Unsafe Condition

    This AD was prompted by reports of five engine in-flight 
shutdowns and seven unplanned engine removals due to clogging of No. 
4 bearing compartment oil pressure and scavenge tubes. We are 
issuing this AD to prevent an engine fire, a fractured fan drive 
shaft, and damage to the airplane.

(e) Compliance

    (1) If you have incorporated Pratt & Whitney ASB No. PW4ENG-A72-
436; SB No. PW4ENG-79-76; and SB No. PW4ENG-72-472, then no further 
action is required.
    (2) Comply with this AD within the compliance times specified, 
unless already done.

[[Page 16923]]

(f) Inspection and Cleaning of No. 4 Bearing Compartment for Coking

    (1) Within 1,000 cycles-in-service (CIS) after the effective 
date of this AD, inspect and clean the No. 4 bearing compartment.
    (2) Thereafter, within every additional 1,000 CIS, re-inspect 
and clean the No. 4 bearing compartment.

(g) Modification To Stop Buildup of Coking in the No. 4 Bearing 
Compartment, and Rerouting of the No. 4 Bearing Pressure and Scavenge 
Tubes

    At the next engine shop visit, but not to exceed 5 years after 
the effective date of this AD, do the following:
    (1) Replace the No. 4 bearing packing transfer tube assembly;
    (2) Replace the No. 4 bearing internal scavenge tube assembly;
    (3) Remove the No. 4 bearing shield, and the No. 4 bearing 
shield option; and
    (4) Install the new No. 4 bearing shield options.
    (5) Modify the turbine exhaust case to relocate the No. 4 
bearing pressure and scavenge tube ports to below the engine 
centerline;
    (6) Replace the internal No. 4 bearing pressure and scavenge 
tubes;
    (7) Modify or replace the turbine case cooling brackets to 
support the new No. 4 bearing pressure and scavenge tubes;
    (8) Replace the turbine case manifolds as necessary; and
    (9) Install the new brackets and clamps to support the new 
routing configuration.

(h) Terminating Action to the Repetitive Inspections and Cleaning

    Performing the modifications specified in paragraphs (g)(1) 
through (g)(9) of this AD is terminating action for the repetitive 
inspections and cleanings specified in paragraph (f)(2) of this AD.

(i) Definition of Shop Visit

    For the purpose of this AD, a shop visit is when the engine is 
inducted into the shop for any maintenance involving the separation 
of pairs of major mating engine flanges (lettered flanges). However, 
the separation of engine flanges solely for the purposes of 
transporting the engine without subsequent engine maintenance is not 
an engine shop visit.

(j) Alternative Methods of Compliance (AMOCs)

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

(k) Related Information

    (1) For more information about this AD, contact James Gray, 
Aerospace Engineer, Engine & Propeller Directorate, FAA, 12 New 
England Executive Park, Burlington, MA 01803; phone: 781-238-7742; 
fax: 781-238-7199; email: [email protected].
    (2) Pratt & Whitney ASB No. PW4ENG-A72-436; SB No. PW4ENG-79-76; 
and SB No. PW4ENG-72-472, pertain to the subject of this AD.
    (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. For information on the availability of this 
material at the FAA, call 781-238-7125.

(l) Material Incorporated by Reference

    None.

    Issued in Burlington. Massachusetts, on March 19, 2012.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-6996 Filed 3-22-12; 8:45 am]
BILLING CODE 4910-13-P

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