AD 2007-17-21

[Federal Register Volume 72, Number 164 (Friday, August 24, 2007)]
[Rules and Regulations]
[Pages 48549-48551]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E7-16665]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-23742; Directorate Identifier 2005-NE-53-AD; 
Amendment 39-15180; AD 2007-17-21]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney (PW) JT9D-7R4 Series 
Turbofan Engines

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

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for PW 
JT9D-7R4 series turbofan engines. This AD requires removing reduced 
cooling flow 2nd stage high pressure turbine (HPT) vane assemblies, 
part numbers (P/Ns) 797282, 796972, 800082, 800072, 803182, 803282, and 
822582, installed in 2nd stage HPT vane cluster assemblies P/Ns 797592, 
797372, 799872, 799782, and 822572. It also requires a visual and a 
fluorescent penetrant inspection (FPI) of the 2nd stage HPT air seal 
assembly, P/N 815097. This AD results from a report of an uncontained 
failure of the 2nd stage HPT air seal assembly, caused by the air seal 
assembly brace disengaging from the air seal, due to insufficient 
cooling air flow. We are issuing this AD to prevent uncontained failure 
of the 2nd stage HPT air seal assembly, leading to engine in-flight 
shutdown and damage to the airplane.

DATES: This AD becomes effective September 28, 2007. The Director of 
the Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of September 28, 2007.

ADDRESSES: You can get the service information identified in this AD 
from Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone 
(860) 565-8770; fax (860) 565-4503.
    You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> 
or at the 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: Mark Riley, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; telephone (781) 238-7758, 
fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed AD. The proposed AD applies to PW JT9D-7R4E1, -7R4E4, -
7R4G2, and -7R4H1 turbofan engines. We published the proposed AD in the 
Federal Register on February 2, 2007 (72 FR 4964). That action proposed 
to require removal of reduced cooling flow 2nd stage HPT vane 
assemblies. It also proposed to require a visual and an FPI of the 2nd 
stage HPT air seal assembly.

Examining the AD Docket

    You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>; 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 the NPRM, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Operations office (telephone (800) 647-5527) is provided in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

Comments

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

Revise the Cost Impact

    FEDEX requests that we revise the estimated cost impact to 
implement the AD because they believe that the actual cost of 
modification (according to PW Alert Service Bulletin (ASB) JT9D-7R4-
A72-596, dated September 15, 2005) for one set of HPT 2nd stage vane 
assemblies will be approximately $23,000, instead of $5,400 projected 
by the proposed AD. We do not agree. We

[[Page 48550]]

provided the estimated material cost of $5,400 per engine from the 
engine manufacturer in the Costs of Compliance section in the proposed 
AD. Parts included new 2nd stage HPT vane covers, part number (P/N) 
822734, and rivets, P/N ST1219-213, that are required to modify the 2nd 
stage HPT vane cluster assemblies, as specified in ASB JT9D-7R4-A72-
596, dated September 15, 2005. However, based on latest pricing 
information in the PW spare parts price catalog, we increased the 
estimated material cost to $6,700. We also estimate that it will take 
about 65.5 work-hours per engine to perform the actions, and that the 
average labor rate is $80 per work-hour. Based on these figures, we 
estimate the total cost of the AD to be $11,940 per engine.

Revise the Applicability Section

    Boeing Company asks that we revise paragraph (c) of the AD to 
remove the reference to the Boeing model 747-200B, -200C, -200F, and -
300 airplanes. Boeing states that the JT9D-7R4E1, -7R4E4, and -7R4H1 
are not used on any model Boeing 747 and the description implies that 
these engines may be installed on the Boeing 747 airplane. We partially 
agree. We removed the letter designations for the 747-200 series 
airplanes. However, we do not agree that the airplane listing in 
paragraph (c) implies that the JT9D-7R4E1, -7R4E4, and -7R4H1 engines 
may be installed on the Boeing 747. The airplane references in 
paragraph (c) are informative only. The Type Certificate Data Sheet for 
an airplane specifies the engines that are installed on the airplane, 
not the applicability paragraph of an AD.
    PW asks that we revise the Applicability section to clarify the 
affected engine models. They also request that we add the following 
aircraft to the list of airplanes that can have these engines 
installed: Boeing 767-200, Airbus A300-600, and A310-300.
    We partially agree and revised the Applicability section of the AD 
to add Boeing 767-200, and Airbus A300-600 and A310-300 airplane models 
to paragraph (c) of the AD. We do not agree that we need to clarify the 
engine models with Pratt & Whitney internal model designation. We 
specify the affected engines by the model designations specified in the 
Type Certificate Data Sheet for the engine.

Revise Paragraph (f) of the Compliance Section

    PW asks that we revise paragraph (f) of the Compliance section to 
delete the specific lenticular seal part number reference, as there are 
other lenticular seal part numbers in the field that will also require 
visual and FPI inspections at the next HPT module exposure. We 
partially agree. The specific lenticular seal part number should be 
removed from paragraph (f) of the Compliance section of the AD because 
there are other lenticular seal part numbers in the field that will 
also require inspections. However, to prevent further delay in 
addressing the unsafe condition, we are issuing this AD with the 
specific lenticular seal part number listed. Removal of the part number 
will expand the number of parts requiring inspection and we must give 
the public an opportunity to comment on this change before we can 
incorporate it. We will supersede this AD to remove the lenticular seal 
part number.

List Required Lenticular Seal Inspections

    PW asks that we revise paragraph (f) of the Compliance section to 
list all of the specific inspections required for the lenticular seal. 
We agree and listed each inspection procedure in the PW engine manual 
required for the lenticular seal. We also changed the paragraph to (g).

Revise Paragraph (g) of the Compliance Section

    PW also asks that we revise paragraph (g) of the Compliance section 
to reference the associated 2nd stage HPT vane cluster assemblies 
(higher level assembly) that have reduced cooling flow 2nd stage HPT 
vane assemblies installed, because airlines may not recognize 
individual 2nd stage vane assemblies. We agree. We revised paragraph 
(g) of the Compliance section to state the following: ``At the next HPT 
module exposure, remove reduced cooling flow 2nd stage HPT vane 
assemblies, P/Ns 797282, 796972, 800082, 800072, 803182, 803282, and 
822582, installed in 2nd stage HPT vane cluster assemblies, P/Ns 
797592, 797372, 799872, 799782, and 822572.'' We also designated the 
paragraph as (f).

Correct Errors and Remove Duplicate P/N Reference

    Boeing Company asks that we correct typographical errors for the 
engine designations in paragraph (c) in the Applicability section. 
Boeing states that the JT9D-74R4E1, -74R4E4, -74R4G2, and -74R4H1 
should be JT9D-7R4E1, -7R4E4, -7R4G2, and -7R4H1, respectively.
    Boeing also asks that we revise paragraph (g) in the Compliance 
section to remove a duplicate reference to part number 803182. We agree 
and corrected the Applicability section and the duplicate P/N reference 
in paragraph (g).

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 proposed AD would affect 85 PW JT9D-7R4 
series turbofan engines installed on airplanes U.S. registry. We also 
estimate that it will take about 65.5 work-hours per engine to perform 
the actions, and that the average labor rate is $80 per work-hour. 
Required parts will cost about $6,700 per engine. Based on these 
figures, we estimate the total cost of the AD to U.S. operators to be 
$1,014,900.

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 48551]]

    (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 adding the following new airworthiness 
directive:

2007-17-21 Pratt & Whitney: Amendment 39-15180. Docket No. FAA-2006-
23742; Directorate Identifier 2005-NE-53-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective 
September 28, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Pratt & Whitney (PW) JT9D-7R4G2, -7R4E1, 
-7R4E4, and -7R4H1 series turbofan engines. These engines are 
installed on, but not limited to, Boeing 747-200, -300, 767-200, and 
Airbus A300-600 and A310-300 series airplanes.

Unsafe Condition

    (d) This AD results from a report of an uncontained failure of 
the 2nd stage high pressure turbine (HPT) air seal assembly, caused 
by the air seal assembly brace disengaging from the air seal, due to 
insufficient cooling air flow. We are issuing this AD to prevent 
uncontained failure of the 2nd stage HPT air seal assembly, leading 
to engine in-flight shutdown and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed at the next HPT module exposure after the effective 
date of this AD, unless the actions have already been done.
    (f) At the next HPT module exposure, remove reduced cooling flow 
2nd stage HPT vane assemblies part numbers (P/Ns): 797282, 796972, 
800082, 800072, 803182, 803282, and 822582, installed in 2nd stage 
HPT vane cluster assemblies: P/Ns 797592, 797372, 799872, 799782, 
and 822572.
    (g) For 2nd stage HPT air seals that have operated in an engine 
with reduced cooling flow HPT vane assemblies, at the next HPT 
module exposure do the following:
    (1) Perform a onetime visual inspection of the 2nd stage HPT air 
seal assembly, P/N 815097, using instructions in JT9D-7R4 engine 
manual, Section 72-51-22, Inspection/Check-01, paragraphs 1.D.(1), 
1.D.(4), and 1.D.(6).
    (2) Perform a fluorescent penetrant inspection (FPI) of the 2nd 
stage HPT air seal assembly for cracks, using instructions in JT9D-
7R4 engine manual, Section 71-51-00, Inspection/Check-03.

Definition

    (h) For the purpose of this AD, an HPT module exposure is 
defined as removing the 1st stage HPT rotor or the 2nd stage HPT 
rotor from the HPT case.

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 JT9D-7R4-A72-596, 
dated September 15, 2005, contains information for modifying the 
reduced cooling flow 2nd stage HPT vane assemblies.

    Issued in Burlington, Massachusetts, on August 17, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E7-16665 Filed 8-23-07; 8:45 am]
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