Document ID: FAA-2010-0725-0003
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Pratt and Whitney PW4000 Series Turbofan Engines
Posted Date: 2010-08-04T04:00Z

[Federal Register: June 3, 2010 (Volume 75, Number 106)]
[Proposed Rules]               
[Page 31330-31332]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03jn10-20]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0384; Directorate Identifier 2010-NE-18-AD]
RIN 2120-AA64

 
Airworthiness Directives; Pratt & Whitney PW4000 Series Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Pratt & Whitney PW4000 series turbofan engines. This proposed AD 
would require a one-time visual inspection of the No. 3 bearing oil 
pressure tube, part number (P/N) 51J041-01, P/N 50J604-01, or P/N 
50J924-01. Tubes that are found cracked or repaired would be required 
to be removed from service. This proposed AD would also prohibit 
repaired tubes from being installed. This proposed AD results from one 
report of a repaired No. 3 bearing oil tube that caused an engine in-
flight shutdown, seven reports of repaired No. 3 bearing oil pressure 
tubes found cracked that led to unscheduled engine removals, and one 
report of a test cell event from a repaired tube that cracked. We are 
proposing this AD to prevent cracking of No. 3 bearing oil pressure 
tubes which could result in internal oil fire, failure of the high-
pressure turbine (HPT) disks, uncontained engine failure, and damage to 
the airplane.

DATES: We must receive any comments on this proposed AD by August 2, 
2010.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     Federal eRulemaking Portal: Go to http://
www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.

FOR FURTHER INFORMATION CONTACT: James Gray, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803;

[[Page 31331]]

e-mail: james.gray@faa.gov; telephone (781) 238-7742; fax (781) 238-
7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2010-0384; Directorate 
Identifier 2010-NE-18-AD'' in the subject line of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of the proposed AD. We will consider 
all comments received by the closing date and may amend the proposed AD 
in light 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 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, the name of the individual who 
sent the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78).

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office 
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 Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

Discussion

    In August 2009, we received a report of a Pratt & Whitney PW4000 
series turbofan engine failure during flight. Investigation revealed 
that the engine had an internal oil fire caused by a cracked No. 3 
bearing oil pressure tube, and that the tube was previously weld-
repaired. That fire led to failure of the high-pressure compressor rear 
shaft and damage to the HPT stages 1-2 air seal and HPT disks. Since 
2007, we have also received seven other reports of repaired No. 3 
bearing oil pressure tubes cracking, resulting in unscheduled engine 
removals. The operational interaction of the tube and diffuser case can 
cause wear. A weld-repaired tube can exhibit decreased capability and 
be more likely to crack than a tube that has not been repaired. Because 
of the type of environment these tubes operate in, tubes that are 
cracked or repaired, or if suspected that the tube was repaired, would 
be required to be removed from service. Operating the engines with 
cracked No. 3 bearing oil pressure tubes, if not corrected, could 
result in internal oil fire, failure of the HPT disks, uncontained 
engine failure, and damage to the airplane.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. We are proposing this AD, which would 
require:
     A one-time visual inspection of the No. 3 bearing oil 
pressure tube, P/N 51J041-01, P/N 50J604-01, or P/N 50J924-01; and
     Removal from service if found cracked or repaired, or if 
suspected that the tube was repaired; and
     A prohibition on installing repaired tubes.

Costs of Compliance

    We estimate that this proposed AD would affect 973 PW4000 series 
turbofan engines installed on airplanes of U.S. registry. We also 
estimate that it would take about 10 minutes per engine to perform the 
proposed one-time visual inspection when the tube has been removed, and 
that the average labor rate is $85 per work-hour. Required parts would 
cost about $9,154 per engine. Based on these figures, we estimate the 
total cost of the proposed AD to U.S. operators to be $8,923,383.

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 have 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 that the proposed AD:
    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); and
    3. Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 14 CFR part 39 as 
follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

    2. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Pratt & Whitney: Docket No. FAA-2010-0384; Directorate Identifier 
2010-NE-18-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by August 2, 
2010.

Affected ADs

    (b) None.

[[Page 31332]]

Applicability

    (c) This AD applies to the following Pratt & Whitney turbofan 
engines, with No. 3 bearing oil pressure tube, part number (P/N) 
51J041-01, P/N 50J604-01, or P/N 50J924-01, installed:

PW4000-94'' Engines

    (1) PW4000-94'' engines affected are PW4050, PW4052, PW4056, 
PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4152, PW4156, PW4156A, 
PW4158, PW4160, PW4460, PW4462, and PW4650, including models with 
any dash number suffix.

PW4000-100'' Engines

    (2) PW4000-100'' engines affected are PW4164, PW4168, PW4168A, 
PW4164C, PW4164C/B, PW4170, PW4168A-1D, PW4168-1D, PW4164-1D, 
PW4164C-1D, and PW4164C/B-1D, including models with any dash number 
suffix.

PW4000-112'' Engines

    (3) PW4000-112'' engines affected are PW4074, PW4074D, PW4077, 
PW4077D, PW4084, PW4084D, PW4090, PW4090-3, PW4090D, and PW4098, 
including models with any dash number suffix.
    (4) These engines are installed on, but not limited to, Airbus 
A300, A310, and A330 series, Boeing MD-11, 747, 767, and 777 series, 
airplanes.

Unsafe Condition

    (d) This AD results from one report of a repaired No. 3 bearing 
oil pressure tube that cracked and caused an engine in-flight 
shutdown, one report of a test cell event, and eight reports since 
2007, of repaired No. 3 bearing oil pressure tubes found cracked 
that led to unscheduled engine removals. We are issuing this AD to 
prevent cracking of No. 3 bearing oil pressure tubes which could 
result in internal oil fire, failure of the high-pressure turbine 
disks, uncontained engine failure, and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed the next time the No. 3 bearing oil pressure tube is 
removed from the engine after the effective date of this AD, unless 
the actions have already been done.

One-Time Visual Inspection of the No. 3 Bearing Oil Pressure Tube

    (f) Perform a one-time visual inspection of the exterior of the 
No. 3 bearing oil pressure tube for cracks and evidence of being 
repaired.
    (1) Remove the tube from service if any cracks are found.
    (2) Remove the tube from service if found repaired, or if 
suspected that the tube was repaired.
    (g) After the effective date of this AD, do not install any 
repaired No. 3 bearing oil pressure tube into any engine.
    (h) Guidance on the No. 3 bearing oil pressure tube visual 
inspection can be found in:
    (1) Pratt & Whitney Clean, Inspect, Repair Manual PN 51A357, 72-
41-20 for PW4000-94'' and PW4000-100'' series engines; or
    (2) Pratt & Whitney Clean, Inspect, Repair Manual PN 51A750, 72-
41-20 for PW4000-112'' series engines.

Alternative Methods of Compliance

    (i) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD, if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (j) Contact James Gray, Aerospace Engineer, Engine Certification 
Office, FAA, Engine and Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: james.gray@faa.gov; 
telephone (781) 238-7742; fax (781) 238-7199, for more information 
about this AD.
    (k) Contact Pratt & Whitney, 400 Main St., East Hartford, CT 
06108, telephone (860) 565-7700; fax (860) 565-1605, for a copy of 
the repair manuals referenced in paragraphs (h)(1) and (h)(2) of 
this AD.

    Issued in Burlington, Massachusetts, on May 27, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2010-13314 Filed 6-2-10; 8:45 am]
BILLING CODE 4910-13-P