E9-18941. Airworthiness Directives; Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, and -17 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 JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, and -17 turbofan engines with 2nd stage fan blades, part number (P/N) 433802, 645902, 759902, 695932, 678102, or 746402 installed. That AD currently requires initial and repetitive ultrasonic inspection (UI) and fluorescent penetrant inspection (FPI) of those P/N 2nd stage fan blades. This proposed AD would replace the required FPI with eddy current inspection (ECI) on all affected 2nd stage fan blades and would maintain the requirement of ultrasonic inspection (UI) of the blade root attachment on some of the affected 2nd stage fan blades. This proposed AD would also introduce an optional terminating action to the repetitive blade inspections for certain engine models. This proposed AD results from reports of 10 fractures of 2nd stage fan blades since AD 87-14-01R1 became effective. We are proposing this AD to prevent uncontained failure of 2nd stage fan blades, which could result in damage to the airplane.

DATES:

We must receive any comments on this proposed AD by October 6, 2009.

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: [phone].

FOR FURTHER INFORMATION CONTACT:

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

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-2009-0317; Directorate Identifier 79-ANE-18” 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).

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 [phone]) 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 87-14-01 R1, Amendment 39-6359 (54 FR 43954, October 30, 1989). That AD requires initial and repetitive UI and FPI of P/N 433802, 645902, 759902, 695932, 678102, and 746402 2nd stage fan blades. That AD was the result of reports of on-going fractures of 2nd stage fan blades since 1980. That condition, if not corrected, could result in uncontained failure of 2nd stage fan blades, which could result in damage to the airplane.

Actions Since AD 87-14-01 R1 Was Issued

Since AD 87-14-01 R1 was issued, Pratt & Whitney has developed and published an ECI procedure for inspecting the 2nd stage fan blade pin-root holes. We have reviewed this procedure and determined that mandating this ECI procedure will result in an increased level of safety for the affected engines.

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, for 2nd stage fan blades P/Ns 678102 and 746402, an ECI of the blade pin-root holes for cracks, and for 2nd stage fan blades P/Ns 433802, 645902, 759902, and 695932, an ECI of the blade pin-root holes and UI the blade root attachment for cracks. This proposed AD would also eliminate the JT8D-1, -1A, and -1B engines from the applicability, because those engine models have either been converted to other affected engine models included in the proposed AD or retired from service.

Costs of Compliance

We estimate that this proposed AD would affect 1,380 engines installed on airplanes of U.S. registry. We also estimate that it would take about 25 work-hours per engine to perform one inspection cycle, and that the average labor rate is $80 per work-hour. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $2,760,000.

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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-6359 (54 FR 43954, October 30, 1989) and by adding a new airworthiness directive to read as follows:

Pratt & Whitney: Docket No. FAA-2009-0317; Directorate Identifier 79-ANE-18.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by October 6, 2009.

Affected ADs

(b) This AD supersedes AD 87-14-01 R1, Amendment 39-6359.

Applicability

(c) This AD applies to Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, and -17 turbofan engines, with 2nd stage fan blades, part number (P/N) 433802, 645902, 759902, 695932, 678102, or 746402, installed. These engines are installed on, but not limited to, Boeing 727, 737, and McDonnell Douglas DC-9 series airplanes.

Unsafe Condition

(d) This AD results from reports of 10 fractures of 2nd stage fan blades since AD 87-14-01R1 became effective. We are issuing this AD to prevent uncontained failure of 2nd stage fan blades, which could result in 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.

2nd Stage Fan Blade Inspections

(f) For 2nd stage fan blades, P/N 678102 and P/N 746402, perform an eddy current inspection (ECI) of the blade pin-root holes for cracks, and for 2nd stage fan blades, P/Ns 433802, 645902, 759902, and 695932, perform an ECI of the blade pin-root holes and perform an ultrasonic inspection (UI) of the blade root attachment for cracks, as follows:

(1) Perform an inspection at the first disassembly of the 2nd stage fan rotor from the low-pressure (LP) compressor after accumulation of 3,000 cycles-in-service (CIS) since the last inspection of the blade root attachment, not to exceed 10,000 CIS since last inspection.

(2) If the 2nd stage fan blades were new at their last installation onto the 2nd stage fan disk, inspect at the first disassembly of the 2nd stage fan rotor from the LP compressor after accumulating 3,000 cycles-since-new (CSN), not to exceed 10,000 CSN.

(3) Thereafter, inspect the 2nd stage fan blades at each disassembly of the 2nd stage fan rotor from the LP compressor after accumulating 3,000 CIS, not to exceed 10,000 CIS since the last inspection.

(4) Guidance on performing ECIs and UIs of the 2nd stage fan blade pin-root holes and blade root attachments can be found in Pratt & Whitney Maintenance Advisory Notice MAN-JT8D-1-08.

(5) Remove from service before further flight any 2nd stage fan blades that are found cracked.

Optional Terminating Action

(g) For JT8D-9, -9A, -11, -15, and -17 engines, as optional terminating action to the repetitive inspections required by this AD, replace the affected 2nd stage fan blades with redesigned 2nd stage fan blades using Pratt & Whitney Service Bulletin No. 5866, Revision 2, dated October 20, 1998.

Alternative Methods of Compliance

(h) The Manager, Engine Certification Office, FAA, 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

(i) Contact Kevin Dickert, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone], fax [phone], for more information about this AD.

(j) Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone [phone]; fax [phone], for a copy of the service information referenced in this AD.

Issued in Burlington, Massachusetts, on August 3, 2009.

Francis A. Favara,

Manager, Engine and Propeller Directorate, Aircraft Certification Service.