05-21804. Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) for Pratt & Whitney (PW) JT9D series turbofan engines. That AD currently requires revisions to the Airworthiness Limitations Section (ALS) of the manufacturer's Instructions for Continued Airworthiness (ICA) to include required enhanced inspection of selected critical life-limited parts at each piece-part opportunity. This proposed AD would modify the JT9D series engines ALS sections of the manufacturer's manuals and an air carrier's approved continuous airworthiness maintenance program to incorporate additional inspection requirements. The mandatory inspections are needed to identify those critical rotating parts with conditions, which if allowed to continue in service, could result in uncontained failures. We are proposing this AD to prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane.

DATES:

We must receive any comments on this proposed AD by January 3, 2006.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD:

• By mail: Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 98-ANE-47-AD, 12 New England Executive Park, Burlington, MA 01803-5299.
• By fax: [phone].
• By e-mail: [e-mail].

You may examine the AD docket at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT:

Kevin Donovan, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone [phone], fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “AD Docket No. 98-ANE-47-AD” in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it; we will date-stamp your postcard and mail it back to you. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. If a person contacts us verbally, and that contact relates to a substantive part of this proposed AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

Examining the AD Docket

You may examine the AD Docket (including any comments and service information), by appointment, between 8 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.

Discussion

On April 12, 2002, we issued AD 2002-08-11, Amendment 39-12719 (67 FR 19663, April 23, 2002), to require revisions to the JT9D series engines ALS of the manufacturer's Instructions for Continued Airworthiness to include required enhanced inspection of selected critical life-limited parts at each piece-part opportunity.

New Inspection Procedures

Since we issued AD 2002-08-11, PW has added mandatory eddy current inspections (ECIs) for web cooling holes in high pressure turbine (HPT) stage 1 disks, installed in engine models JT9D-7R4, -7R4D1, -7R4E, -7R4E1 engines, and for HPT stage 2 disks installed in JT9D-7, -7A, -7H, -7AH, -7F, -7J, -20, and -20J engines. The mandatory inspections are needed to identify those critical rotating parts with conditions, which if allowed to continue in service, could result in uncontained failures.

FAA's Determination and Requirements of the Proposed AD

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would supersede AD 2002-08-11 to require:

• Adding ECIs for web cooling holes in HPT stage 1 disks installed in engine models JT9D-7R4, -7R4D1, -7R4E, -7R4E1 engines; and
• Adding ECIs for web cooling holes in HPT stage 2 disks installed in JT9D-7, -7A, -7H, -7AH, -7F, -7J, -20, and -20J engines; and
• Clarification of the inspections listed in the Inspection column of the Mandatory Inspections Table in this AD.

The proposed AD would incorporate the additional inspection requirements into the Airworthiness Limitations Section of the manufacturer's manuals and an air carrier's approved continuous airworthiness maintenance program.

Costs of Compliance

About 1,978 PW JT9D series turbofan engines of the affected design are in the worldwide fleet. We estimate that 837 of these engines are installed on U.S.-registered airplanes and would be affected by this proposed AD. We also estimate that about one work hour per engine is needed to perform the proposed actions, and that the average labor rate is $65 per work hour. Since this is an added inspection requirement that will be part of the normal maintenance cycle, no additional parts costs are involved. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $54,405.

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 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 summary of the costs to comply with this proposal and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 98-ANE-47-AD” in your request.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, 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 39-12719 (67 FR 19663, April 23, 2002), and by adding a new airworthiness directive to read as follows:

Pratt & Whitney: Docket No. 98-ANE-47-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by January 3, 2006.

Affected ADs

(b) This AD supersedes AD 2002-08-11, Amendment 39-12719.

Applicability

(c) This AD applies to Pratt & Whitney (PW) JT9D-3A, -7, -7A, -7H, -7AH, -7F, -7J, -20J, -59A, -70A, -7Q, -7Q3, -7R4D, -7R4D1, -7R4E, -7R4E1, -7R4E4, -7R4G2, and -7R4H1 series turbofan engines, installed on but not limited to Boeing 747 and 767 series, McDonnell Douglas DC-10 series, and Airbus Industrie A300 and A310 airplanes.

Unsafe Condition

(d) This AD results from the need to require enhanced inspection of selected critical life-limited parts of JT9D series turbofan engines. We are issuing this AD to prevent failure of critical life-limited rotating engine parts, which could result in an uncontained engine failure and damage to the airplane.

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.

(f) Within the next 180 days after the effective date of this AD, revise the manufacturer's Instructions for Continued Airworthiness Airworthiness Limitations Section (ALS), and for air carrier operations revise the approved continuous airworthiness maintenance program by adding the following:

“MANDATORY INSPECTIONS

(1) Perform inspections of the following parts at each piece-part opportunity in accordance with the instructions provided in the applicable manual provisions:

Engine model	Engine manual part number (P/N)	Part nomenclature	Inspect per manual section	Inspection/check
7/7A/7AH/7F, 7H/7J/20/20J	* 646028 (or the equivalent customized versions, 770407 and 770408)	All Fan Hubs	72-31-04	Inspection-02.
		All HPC Stage 5—15 Disks and Rear Compressor Drive Turbine Shafts	72-35-00	Inspection-03.
		All HPT Stage 1—2 Disks and Hubs	72-51-00	Inspection-03.
		All HPT Stage 2 Disk Web Cooling Holes	71-51-02	Inspection-05.
		All LPT Stage 3—6 Disks and Hubs	72-52-00	Inspection-03.
59A/70A	754459	All Fan Hubs	72-31-00	Check-00.
		All HPC Stage 5—15 Disks and Rear Compressor Drive Turbine Shafts	72-35-00	Check-00.
		All HPT Stage 1—2 Disks and Hubs	72-51-00	Check-03.
		All HPT Stage 1 Disk Web Cooling Holes	72-51-02	Check-03.
		All LPT Stage 3—6 Disks and Hubs	72-52-00	Check-03.
7Q/7Q3	777210	All Fan Hubs	72-31-00	Inspection-03.
		All HPC Stage 5—15 Disks and Rear Compressor Drive Turbine Shafts	72-35-00	Inspection-03.
		All HPT Stage 1—2 Disks and Hubs	72-51-00	Inspection-03.
		All HPT Stage 1 Disk Web Cooling Holes	72-51-06	Inspection-03.
		All LPT Stage 3—6 Disks and Hubs	72-52-00	Inspection-03.
7R4	785058, 785059, and 789328	All Fan Hubs	72-31-00	Inspection/Check-03.
		All HPC Stage 5—15 Disks and Rear Compressor Drive Turbine Shafts	72-35-00	Inspection/Check 03.
		All HPT Stage 1—2 Disks and Hubs	72-51-00	Inspection/Check-03.
		All LPT Stage 3—6 Disks and Hubs	72-52-00	Inspection/Check-03.
7R4D/D1/E/E1	785058 and 785059	All HPT Stage 1 Disk Web Cooling Holes	72-51-06	Inspection/Check-02.
* P/N 770407 and 770408 are customized versions of P/N 646028 engine manual.

(2) For the purposes of these mandatory inspections, piece-part opportunity means:

(i) The part is considered completely disassembled when done in accordance with the disassembly instructions in the manufacturer's engine manual; and

(ii) The part has accumulated more than 100 cycles-in-service since the last piece-part opportunity inspection, provided that the part was not damaged or related to the cause for its removal from the engine.”

Alternative Methods of Compliance

(g) You must perform these mandatory inspections using the ALS of the Instructions for Continued Airworthiness and the applicable Engine Manual unless you receive approval to use an alternative method of compliance under paragraph (h) of this AD. Section 43.16 of the Federal Aviation Regulations (14 CFR 43.16) may not be used to approve alternative methods of compliance or adjustments to the times in which these inspections must be performed.

(h) 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.

Maintaining Records of the Mandatory Inspections

(i) You have met the requirements of this AD when you change the manufacturer's Instructions for Continued Airworthiness ALS specified in paragraph (f) of this AD, and, for air carriers operating under part 121 of the Federal Aviation Regulations (14 CFR part 121), when you modify your continuous airworthiness maintenance plan to reflect those changes. You do not need to record each piece-part inspection as compliance to this AD but you must maintain records of those inspections according to the regulations governing your operation. For air carriers operating under part 121, you may use either the system established to comply with section 121.369 or an alternative accepted by your principal maintenance inspector if that alternative:

(1) Includes a method for preserving and retrieving the records of the inspections resulting from this AD; and

(2) Meets the requirements of section 121.369(c); and

(3) Maintains the records either indefinitely or until the work is repeated.

(j) These record keeping requirements apply only to the records used to document the mandatory inspections required as a result of revising the ALS of the Instructions for Continued Airworthiness as specified in paragraph (f) of this AD, and do not alter or amend the record keeping requirements for any other AD or regulatory requirement.

Issued in Burlington, Massachusetts, on October 27, 2005.

Peter A. White,

Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service.