[Federal Register Volume 72, Number 37 (Monday, February 26, 2007)]
[Rules and Regulations]
[Pages 8263-8265]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-3017]


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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; 
Amendment 39-14959; AD 2007-04-26]
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: Final rule.

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[[Page 8264]]

SUMMARY: The FAA is superseding 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 AD requires 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) parts. This proposed AD also applies to 
engines reassembled with a PMA HPC exit inner and or outer brush seal 
packs. This AD results from a request to include PMA HPC exit inner and 
outer brush seal packs and to include the engines with PMA parts 
already installed, in the AD. We are issuing this AD to prevent 
uncontained engine failure, damage to the airplane, and injury to 
passengers.

DATES: This AD becomes effective April 2, 2007.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in Room PL-401 on the plaza level of the Nassif 
Building, 400 Seventh Street, SW., Washington, DC.

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; e-mail: 
[email protected].

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed AD. The proposed AD applies to Pratt & Whitney PW4077D, 
PW4084D, PW4090, and PW4090-3 turbofan engines that were reassembled 
with previously used HPC exit brush seal packs and new or refurbished 
HPC exit diffuser air seal lands. We published the proposed AD in the 
Federal Register on November 20, 2006 (71 FR 67073). That action 
proposed to require replacing the HPC exit inner and outer brush seal 
packs with new brush seal packs, using either OEM parts, or FAA-
approved PMA parts. That action also proposed to apply to engines 
reassembled with a PMA HPC exit inner and or outer brush seal packs.

Examining the AD Docket

    You may examine the docket that contains the AD, any comments 
received, and any final disposition in person at the Docket Management 
Facility 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.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Add Part Numbers in the AD Applicability

    One commenter, All Nippon Airways, requests that we add Pratt & 
Whitney and PMA part numbers in the AD applicability to avoid confusion 
as to what parts are to be removed and replaced.
    We do not agree. We adequately identified the parts requiring 
replacement, as well as the unsafe condition, in the proposed AD. Pratt 
& Whitney part numbers can be found in Alert Service Bulletin No. PW4G-
112-A72-280, Revision 2, dated January 12, 2007, which we refer to as 
additional information. We did not change the AD.

Request To Allow Installing an HPC Exit Brush Seal Assembly

    One commenter, Pratt & Whitney, requests that we also allow 
installing an HPC exit brush seal assembly, in lieu of installing an 
HPC exit brush seal pack, to comply with the AD.
    We agree. Compliance with the AD can be achieved by installing 
either an HPC exit brush seal pack or an HPC exit brush seal assembly. 
Although installing an HPC exit brush seal assembly may be more costly 
for operators, it may be more convenient. We changed the AD compliance 
to allow for either replacement.

Used Part Prohibition

    For clarification, we added a used part prohibition paragraph in 
the compliance section. It states that engine reassembly with used OEM 
or used FAA-approved PMA HPC exit inner and outer brush seal packs with 
OEM or FAA-approved PMA new HPC exit inner and outer brush seal lands, 
is prohibited.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

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

[[Page 8265]]

    (3) 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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. 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.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration 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 removing Amendment 39-14729 (71 FR 
49335, August 23, 2006), and by adding a new airworthiness directive, 
Amendment 39-14959, to read as follows:

2007-04-26 Pratt & Whitney: Amendment 39-14959. Docket No. FAA-2006-
24034; Directorate Identifier 2006-NE-05-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective April 2, 
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) high pressure 
compressor (HPC) exit inner brush seal pack; and
    (2) Reassembled with a new or refurbished OEM or PMA 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 supersedure results from a request to include PMA 
HPC exit inner and outer brush seal packs and to include the engines 
with PMA parts already installed, in the AD. This AD action is 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. 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 new HPC exit inner and outer brush seal 
packs, or an OEM or FAA-approved PMA new HPC exit brush seal 
assembly, 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.

Used Part Prohibition

    (h) Engine reassembly with used OEM or used FAA-approved PMA HPC 
exit inner and outer brush seal packs with OEM or FAA-approved PMA 
new HPC exit inner and outer brush seal lands, is prohibited.
    (i) 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 January 12, 2007, and in the 
engine overhaul manual.

Alternative Methods of Compliance

    (j) 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

    (k) Pratt & Whitney Alert Service Bulletin No. PW4G-112-A72-280, 
Revision 2, dated January 12, 2007, also pertains to the subject of 
this AD.
    (l) 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; e-mail: [email protected] 
for more information about this AD.

    Issued in Burlington, Massachusetts, on February 16, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E7-3017 Filed 2-23-07; 8:45 am]
BILLING CODE 4910-13-P