Airworthiness Directives; Pratt & Whitney (PW) JT9D-7R4 Series Turbofan Engines, 63510-63512 [E7-22005]

Download as PDF 63510 Federal Register / Vol. 72, No. 217 / Friday, November 9, 2007 / Proposed Rules Affected ADs (b) This AD supersedes AD 2007–02–17, Amendment 39–14894. alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19. Applicability (c) This AD applies to Rolls-Royce Deutschland Ltd & Co KG (RRD) Dart 528, 529, 532, 535, 542, and 552 series turboprop engines. These engines are installed on, but not limited to, Hawker Siddeley, Argosy AW.650, Fairchild Hiller F–27, F–27A, F– 27B, F–27F, F–27G, F–27J, FH–227, FH– 227B, FH–227C, FH–227D, FH–227E, Fokker F.27 all marks; British Aircraft Corporation Viscount 744, 745D and 810; and Gulfstream G–159 airplanes. Related Information (h) LBA airworthiness directive D–2005– 197, dated June 30, 2005, also addresses the subject of this AD. (i) Contact Jason Yang, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; telephone (781) 238–7747, fax (781) 238–7199; e-mail: jason.yang@faa.gov, for more information about this AD. Unsafe Condition (d) This AD results from us including an incorrect engine model and omitting an engine model from the applicability of the existing AD. We are issuing this AD to prevent HPT disk failure, which can result in an uncontained engine failure and damage to the airplane. Issued in Burlington, Massachusetts, on November 2, 2007. Peter A. White, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. E7–22003 Filed 11–8–07; 8:45 am] BILLING CODE 4910–13–P sroberts on PROD1PC70 with PROPOSALS Compliance (e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done. DEPARTMENT OF TRANSPORTATION Intermediate Pressure Turbine (IPT) Disk and High Pressure Turbine (HPT)/IPT Disk Seal Arm Inspections (f) Within 60 days after the effective date of the AD, do either of the following: (1) Perform a dimensional inspection of the IPT disk and repair or replace the IPT disk, if necessary using paragraph 3 of the Accomplishment Instructions of RRD service bulletin (SB) Da72–538, dated June 10, 2005; or (2) Perform an ultrasonic inspection of the disk seal arm contact between the HPT and the IPT using paragraph 3 of the Accomplishment Instructions of RRD SB Da72–536, Revision 1, dated August 25, 2003. (i) For RRD Dart 528, 529, 532, 535, 542 series turboprop engines if wear is outside allowable limits, before June 30, 2007, perform a dimensional inspection and repair or replace the IPT disk, if necessary. Use paragraph 3 of the Accomplishment Instructions of RRD SB Da72–538, dated June 10, 2005. (ii) For RRD Dart 552 series turboprop engines if wear is outside allowable limits, before April 30, 2008, perform a dimensional inspection and repair or replace the IPT disk, if necessary. Use paragraph 3 of the Accomplishment Instructions of RRD SB Da72–538, dated June 10, 2005. (iii) If wear is within allowable limits, perform a dimensional inspection of the IPT disk at the next engine shop visit or at next overhaul, whichever occurs first and repair or replace the IPT disk, if necessary. Use paragraph 3 of the Accomplishment Instructions of RRD SB Da72–538, dated June 10, 2005. [Docket No. FAA–2006–23742; Directorate Identifier 2005–NE–53–AD] Alternative Methods of Compliance (g) The Manager, Engine Certification Office, has the authority to approve VerDate Aug<31>2005 17:12 Nov 08, 2007 Jkt 214001 Federal Aviation Administration 14 CFR Part 39 RIN 2120–AA64 Airworthiness Directives; Pratt & Whitney (PW) JT9D–7R4 Series Turbofan Engines Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of proposed rulemaking (NPRM). AGENCY: SUMMARY: The FAA proposes to supersede an existing airworthiness directive (AD) for PW JT9D–7R4 series turbofan engines. That AD currently requires removing certain reduced cooling flow 2nd stage high pressure turbine (HPT) vane assemblies installed in certain 2nd stage HPT vane cluster assemblies. It also requires a visual and a fluorescent penetrant inspection (FPI) of the 2nd stage HPT air seal assembly, P/N 815097. This proposed AD would require a visual and fluorescent penetrant inspection (FPI) of all part number (P/N) 2nd stage HPT air seal assemblies that were used with reduced cooling flow 2nd stage HPT vane assemblies. This proposed AD results from the manufacturer identifying additional P/N air seal assemblies that are affected by the unsafe condition. We are proposing 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. PO 00000 Frm 00008 Fmt 4702 Sfmt 4702 We must receive any comments on this proposed AD by January 8, 2008. 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. 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: Mark Riley, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: mark.riley@faa.gov; telephone (781) 238–7758, fax (781) 238–7199. SUPPLEMENTARY INFORMATION: DATES: Comments Invited We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA– 2006–23742; Directorate Identifier 2005–NE–53–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). E:\FR\FM\09NOP1.SGM 09NOP1 Federal Register / Vol. 72, No. 217 / Friday, November 9, 2007 / Proposed Rules 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 The FAA proposes to amend 14 CFR part 39 by superseding AD 2007–17–21, Amendment 39–15180 (72 FR 48549, August 24, 2007). That AD requires removing reduced cooling flow 2nd stage HPT vane assemblies. It also requires a visual and an FPI of the 2nd stage HPT air seal assembly. That AD resulted 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. That condition, if not corrected, could result in uncontained failure of the 2nd stage HPT air seal assembly, leading to engine in-flight shutdown and damage to the airplane. Actions Since AD 2007–17–21 Was Issued Since we issued that AD, we determined that we need to expand the applicability of the AD to include all 2nd stage HPT air seal assemblies that were used with 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. sroberts on PROD1PC70 with PROPOSALS Relevant Service Information We have reviewed and approved the technical contents of Pratt & Whitney Alert Service Bulletin JT9D–7R4–A72– 596, dated September 15, 2005, that describes procedures for modifying the reduced cooling flow 2nd stage HPT vane assemblies. 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 at the next HPT module exposure: VerDate Aug<31>2005 17:12 Nov 08, 2007 Jkt 214001 • Removing the reduced cooling flow 2nd stage HPT vane assemblies. • Visual and fluorescent penetrant inspections of the 2nd stage HPT air seal assemblies that have operated in an engine with reduced cooling flow 2nd stage HPT vane assemblies. Costs of Compliance Because this proposed AD is superseding an existing AD to remove the seal assembly P/N, this proposed AD would not add any additional costs beyond the costs included in the original AD. 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. See the ADDRESSES section for a location to examine the regulatory evaluation. PO 00000 Frm 00009 Fmt 4702 Sfmt 4702 63511 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. § 39.13 [Amended] 2. The FAA amends § 39.13 by removing Amendment 39–15180 (72 FR 48549, August 24, 2007), and by adding a new airworthiness directive to read as follows: Pratt & Whitney (PW): Docket No. FAA– 2006–23742; Directorate Identifier 2005– NE–53–AD. Comments Due Date (a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by January 8, 2008. Affected ADs (b) This AD supersedes AD 2007–17–21, Amendment 39–15180. 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 the manufacturer identifying additional part numbers (P/N) air seal assemblies that are affected by the unsafe condition. We are issuing this AD to prevent uncontained failure of the 2nd stage high pressure turbine (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 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. The E:\FR\FM\09NOP1.SGM 09NOP1 63512 Federal Register / Vol. 72, No. 217 / Friday, November 9, 2007 / Proposed Rules JT9D–7R4 engine manual, Section 72–51–22, Inspection/Check–01, paragraphs 1.D.(1), 1.D.(4), and 1.D.(6) contains instructions for the visual inspection. (2) Perform a fluorescent penetrant inspection (FPI) of the 2nd stage HPT air seal assembly for cracks. The JT9D–7R4 engine manual, Section 72–51–00, Inspection/ Check–03, contains instructions for the FPI. Definition (h) For the purpose of this AD, we define an HPT module exposure 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. (k) Contact Mark Riley, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: mark.riley@faa.gov; telephone (781) 238–7758, fax (781) 238–7199, for more information about this AD. Issued in Burlington, Massachusetts, on November 2, 2007. Peter A. White, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. E7–22005 Filed 11–8–07; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2007–0175; Directorate Identifier 2007–NM–184–AD] RIN 2120–AA64 Airworthiness Directives; Boeing Model 757 Airplanes Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of proposed rulemaking (NPRM). sroberts on PROD1PC70 with PROPOSALS AGENCY: SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 757 airplanes. This proposed AD would require changing the wiring of the fuel boost pump and doing other specified actions. This proposed AD results from reports of short circuits in an electrical connector at the wing-to-body electrical VerDate Aug<31>2005 17:12 Nov 08, 2007 Jkt 214001 disconnect panel. We are proposing this AD to prevent a short circuit of the electrical connector for the fuel boost pump, which could cause the instruments for fuel, flap, slat, and aileron systems to malfunction and create a potential ignition source inside the fuel tanks. A potential ignition source inside the fuel tank in combination with flammable fuel vapors could result in a fuel tank explosion and consequent loss of the airplane. DATES: We must receive comments on this proposed AD by December 24, 2007. ADDRESSES: You may send comments by any of the following methods: • Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments. • Fax: 202–493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue, SE., Washington, DC 20590. • Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124–2207. 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 proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Philip Sheridan, Aerospace Engineer, Systems and Equipment Branch, ANM– 130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057–3356; telephone (425) 917–6441; fax (425) 917–6590. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include ‘‘Docket No. PO 00000 Frm 00010 Fmt 4702 Sfmt 4702 FAA–2007–0175; Directorate Identifier 2007–NM–184–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because 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 we receive about this proposed AD. Discussion We have received reports indicating that short circuits occurred in an electrical connector at the wing-to-body electrical disconnect panel, on three Boeing Model 757 airplanes. The airplanes had accumulated between 27,040 and 50,735 total flight hours. On two of the airplanes, the short circuit damaged the fuel quantity indicating system (FQIS) wiring. Wires for some of the fuel boost pumps for the main tank use the same electrical connectors as wires for the FQIS and densitometer circuits. Contamination in these electrical circuits could cause a short circuit from the fuel boost pump wiring to the FQIS and densitometer wiring. A short circuit can put a high-energy electrical transient into the fuel tanks that can act as a potential ignition source. The high-energy electrical transients could also cause the instruments for the fuel, flap, slat, and aileron systems to malfunction. A potential ignition source inside the fuel tank in combination with flammable fuel vapors, if not corrected, could result in a fuel tank explosion and consequent loss of the airplane. Relevant Service Information We have reviewed Boeing Special Attention Service Bulletin 757–28– 0095, dated June 18, 2007, for Model 757–200, –200PF, and –200CB series airplanes; and Boeing Special Attention Service Bulletin 757–28–0096, dated June 18, 2007, for Model 757–300 series airplanes. The service bulletins describe procedures for changing the wiring of the fuel boost pump and doing other specified actions. The other specified actions include doing functional tests of the affected airplane systems. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. E:\FR\FM\09NOP1.SGM 09NOP1

Agencies

[Federal Register Volume 72, Number 217 (Friday, November 9, 2007)]
[Proposed Rules]
[Pages 63510-63512]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-22005]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-23742; Directorate Identifier 2005-NE-53-AD]
RIN 2120-AA64


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

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

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for PW JT9D-7R4 series turbofan engines. That AD 
currently requires removing certain reduced cooling flow 2nd stage high 
pressure turbine (HPT) vane assemblies installed in certain 2nd stage 
HPT vane cluster assemblies. It also requires a visual and a 
fluorescent penetrant inspection (FPI) of the 2nd stage HPT air seal 
assembly, P/N 815097. This proposed AD would require a visual and 
fluorescent penetrant inspection (FPI) of all part number (P/N) 2nd 
stage HPT air seal assemblies that were used with reduced cooling flow 
2nd stage HPT vane assemblies. This proposed AD results from the 
manufacturer identifying additional P/N air seal assemblies that are 
affected by the unsafe condition. We are proposing 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: We must receive any comments on this proposed AD by January 8, 
2008.

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.
    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: Mark Riley, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
mark.riley@faa.gov; telephone (781) 238-7758, 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 comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2006-23742; 
Directorate Identifier 2005-NE-53-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).

[[Page 63511]]

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

    The FAA proposes to amend 14 CFR part 39 by superseding AD 2007-17-
21, Amendment 39-15180 (72 FR 48549, August 24, 2007). That AD requires 
removing reduced cooling flow 2nd stage HPT vane assemblies. It also 
requires a visual and an FPI of the 2nd stage HPT air seal assembly. 
That AD resulted 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. 
That condition, if not corrected, could result in uncontained failure 
of the 2nd stage HPT air seal assembly, leading to engine in-flight 
shutdown and damage to the airplane.

Actions Since AD 2007-17-21 Was Issued

    Since we issued that AD, we determined that we need to expand the 
applicability of the AD to include all 2nd stage HPT air seal 
assemblies that were used with 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.

Relevant Service Information

    We have reviewed and approved the technical contents of Pratt & 
Whitney Alert Service Bulletin JT9D-7R4-A72-596, dated September 15, 
2005, that describes procedures for modifying the reduced cooling flow 
2nd stage HPT vane assemblies.

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 at the next HPT module exposure:
     Removing the reduced cooling flow 2nd stage HPT vane 
assemblies.
     Visual and fluorescent penetrant inspections of the 2nd 
stage HPT air seal assemblies that have operated in an engine with 
reduced cooling flow 2nd stage HPT vane assemblies.

Costs of Compliance

    Because this proposed AD is superseding an existing AD to remove 
the seal assembly P/N, this proposed AD would not add any additional 
costs beyond the costs included in the original AD.

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. 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 39-15180 (72 FR 
48549, August 24, 2007), and by adding a new airworthiness directive to 
read as follows:

Pratt & Whitney (PW): Docket No. FAA-2006-23742; Directorate 
Identifier 2005-NE-53-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 8, 
2008.

Affected ADs

    (b) This AD supersedes AD 2007-17-21, Amendment 39-15180.

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 the manufacturer identifying additional 
part numbers (P/N) air seal assemblies that are affected by the 
unsafe condition. We are issuing this AD to prevent uncontained 
failure of the 2nd stage high pressure turbine (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 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. The

[[Page 63512]]

JT9D-7R4 engine manual, Section 72-51-22, Inspection/Check-01, 
paragraphs 1.D.(1), 1.D.(4), and 1.D.(6) contains instructions for 
the visual inspection.
    (2) Perform a fluorescent penetrant inspection (FPI) of the 2nd 
stage HPT air seal assembly for cracks. The JT9D-7R4 engine manual, 
Section 72-51-00, Inspection/Check-03, contains instructions for the 
FPI.

Definition

    (h) For the purpose of this AD, we define an HPT module exposure 
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.
    (k) Contact Mark Riley, Aerospace Engineer, Engine Certification 
Office, FAA, Engine and Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: mark.riley@faa.gov; 
telephone (781) 238-7758, fax (781) 238-7199, for more information 
about this AD.

    Issued in Burlington, Massachusetts, on November 2, 2007.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E7-22005 Filed 11-8-07; 8:45 am]
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