[Federal Register Volume 71, Number 223 (Monday, November 20, 2006)]
[Proposed Rules]
[Pages 67073-67075]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-19536]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24034; Directorate Identifier 2006-NE-05-AD]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney PW4077D, PW4084D, 
PW4090, and PW4090-3 Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for Pratt & Whitney PW4077D, PW4084D, PW4090, and 
PW4090-3 turbofan engines that were reassembled with previously used 
high pressure compressor (HPC) exit brush seal packs and new or 
refurbished HPC exit diffuser air seal lands. That AD currently 
requires replacing the HPC exit inner and outer brush seal packs with 
new brush seal packs, or replacing the HPC exit brush seal assembly 
with a new HPC exit brush seal assembly. This proposed AD would require 
replacing the HPC exit inner and outer brush seal packs with new brush 
seal packs, using either original equipment manufactured (OEM) parts, 
or FAA-approved part manufacturer approval (PMA) equivalent parts. This 
proposed AD would also apply to engines reassembled with a PMA 
equivalent HPC exit inner and/or outer brush seal packs. This proposed 
AD results from a request to include PMA equivalent HPC exit inner and 
outer brush seal packs and to include the engines with PMA equivalent 
parts already installed, in the AD. We are proposing this AD to prevent 
uncontained engine failure, damage to the airplane, and injury to 
passengers.

DATES: We must receive any comments on this proposed AD by January 19, 
2007.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108; 
telephone (860) 565-8770; fax (860) 565-4503 for the service 
information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Antonio Cancelliere, Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803-5213; 
telephone (781) 238-7751; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments regarding this proposal. Send your

[[Page 67074]]

comments to an address listed under ADDRESSES. Include ``Docket No. 
FAA-2006-24034; Directorate Identifier 2006-NE-05-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://dms.dot.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 
DMS Web site, anyone can find and read the comments in any of our 
dockets, including 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) or you 
may visit http://dms.dot.gov.

Examining the AD Docket

    You may examine the docket that contains the proposal, any comments 
received and any final disposition in person at the DMS Docket Office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Office (telephone (800) 647-5227) is located on 
the plaza level of the Department of Transportation Nassif Building at 
the street address stated in ADDRESSES. Comments will be available in 
the AD docket shortly after the DMS receives them.

Discussion

    On August 14, 2006, the FAA issued AD 2006-17-08, Amendment 39-
14729 (71 FR 49335, August 23, 2006). That AD requires replacing the 
HPC exit inner and outer brush seal packs with new brush seal packs, or 
replacing the HPC exit brush seal assembly with a new HPC exit brush 
seal assembly. That AD was the result of a report of oil leaking into 
the high pressure turbine (HPT) interstage cavity and igniting, leading 
to an engine case penetration and engine in-flight shutdown. That 
condition, if not corrected, could result in uncontained engine 
failure, damage to the airplane, and injury to passengers.

Actions Since AD 2006-17-08 Was Issued

    Since AD 2006-17-08 was issued, an air carrier requested the use of 
PMA equivalent parts to be included in the AD. We agree. The proposed 
AD now also applies to engines reassembled with PMA equivalent HPC exit 
inner and/or outer brush seal packs installed, and allows installation 
of PMA equivalent HPC exit inner and outer brush seal packs for 
compliance to the requirements of the AD.
    Also since AD 2006-17-08 was issued, we determined that the 
requirement in paragraph (g) of that AD, of replacing the HPC exit 
brush seal assembly with a new HPC exit brush seal assembly, is an 
option for the operators to demonstrate compliance to this proposed AD. 
Replacing the HPC exit inner and outer brush seal packs instead, is 
expected to be more economical for operators.

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. For that reason, we are proposing this AD, 
which would require replacing the OEM or PMA equivalent HPC exit inner 
and outer brush seal packs, with OEM or PMA equivalent new brush seal 
packs. Instructions on replacing these parts can be found in Pratt & 
Whitney Service Bulletin No. PW4G-112-A72-280, Revision 2, or Engine 
Overhaul Manual.

Interim Action

    These actions are interim actions and we may take further 
rulemaking actions in the future.

Costs of Compliance

    We estimate that this proposed AD would affect 76 Pratt & Whitney 
PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engines installed on 
airplanes of U.S. registry. We also estimate that it would take about 9 
work-hours per engine to perform the proposed parts replacement, and 
that the average labor rate is $80 per work-hour. Required parts would 
cost about $99,990 per engine. Based on these figures, we estimate the 
total cost of the proposed AD to U.S. operators to be $7,653,950.

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 
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); 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. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

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 removing Amendment 39-14729 (71 FR 
49335, August 23, 2006) and by adding a new airworthiness directive, 
Amendment 39-XXXXX, to read as follows:


[[Page 67075]]


Pratt & Whitney: Docket No. FAA-2006-24034; Directorate Identifier 
2006-NE-05-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 19, 
2007.

Affected ADs

    (b) This AD supersedes AD 2006-17-08, Amendment 39-14729.

Applicability

    (c) This AD applies to Pratt & Whitney PW4077D, PW4084D, PW4090, 
and PW4090-3 turbofan engines that were:
    (1) Reassembled with a previously used original equipment 
manufacturer (OEM) or part manufacturer approval (PMA) equivalent 
high pressure compressor (HPC) exit inner brush seal pack; and
    (2) Reassembled with a new or refurbished OEM or PMA equivalent 
HPC exit diffuser air seal inner land.
    (d) These engines are installed on, but not limited to, Boeing 
777 airplanes.

Unsafe Condition

    (e) This AD results from a request to include PMA equivalent HPC 
exit inner and outer brush seal packs and to include the engines 
with PMA equivalent parts already installed, in the AD. We are 
issuing this AD to prevent uncontained engine failure, damage to the 
airplane, and injury to passengers.

Compliance

    (f) You are responsible for having the actions required by this 
AD performed at the following compliance times, unless the actions 
have already been done.
    (g) Replace the HPC exit inner and outer brush seal packs with 
OEM or FAA-approved PMA equivalent new HPC exit inner and outer 
brush seal packs as follows:
    (1) By 3,000 cycles-in-service (CIS) since a used HPC exit inner 
brush seal pack and a new or refurbished HPC exit diffuser air seal 
land were installed in the engine, or by March 31, 2007, whichever 
occurs later; however
    (2) If on March 31, 2007, the used HPC exit inner brush seal 
pack coupled with a new or refurbished HPC exit diffuser air seal 
inner land assembly has not accumulated 3,000 CIS, then by 3,000 
CIS, or December 31, 2008, whichever occurs first.
    (h) Information on replacing HPC exit inner and outer brush seal 
packs can be found in the Pratt & Whitney Alert Service Bulletin No. 
PW4G-112-A72-280, Revision 2, dated October 2, 2006, and in the 
engine overhaul manual.

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) Pratt & Whitney Alert Service Bulletin No. PW4G-112-A72-280, 
Revision 2, dated October 2, 2006, also pertains to the subject of 
this AD.

    Issued in Burlington, Massachusetts, on November 14, 2006.
Mark Rumizen,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E6-19536 Filed 11-17-06; 8:45 am]
BILLING CODE 4910-13-P