03-30073. Airworthiness Directives; Pratt & Whitney JT9D-3A, -7, -7A, -7F, -7H, -7AH, and -7J Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for Pratt & Whitney (PW) JT9D-3A, -7, -7A, -7F, -7H, -7AH, and -7J turbofan engines, with gearbox pressure tube, part number (P/N) 697896, and No. 4 bearing front pressure manifold, P/N 670663, installed. This AD requires a one-time visual inspection of the gearbox pressure tube and No. 4 bearing front pressure manifold and the attaching clamp assemblies for correct positioning and for wear and damage, and replacement if necessary. This AD is prompted by a report of a failed gearbox pressure tube that resulted in an engine fire. We are issuing this AD to prevent engine fires caused by failed gearbox pressure tubes or failed No. 4 bearing front pressure manifolds.

DATES:

This AD becomes effective December 18, 2003.

We must receive any comments on this AD by February 2, 2004.

ADDRESSES:

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

• By mail: The Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-NE-52-AD, 12 New England Executive Park, Burlington, MA 01803-5299.
• By fax: [phone].
• By e-mail: [e-mail].

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

FOR FURTHER INFORMATION CONTACT:

Keith Lardie, Aerospace Engineer, Aircraft Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

In June of 2003, we became aware that a PW JT9D-7 series turbofan engine gearbox pressure tube failed and caused an engine fire. Investigation revealed that several clamp assemblies that secure the No. 4 bearing front pressure manifold were broken, including some that were missing clamp rubber cushions. Without the clamp rubber cushions, the No. 4 bearing front pressure manifold moved freely due to engine vibration, causing the gearbox pressure tube to fracture, and caused an oil-fed engine fire. A similar failure was reported in 1996, but did not result in a fire.

FAA's Determination and Requirements of This AD

The unsafe condition described previously is likely to exist or develop on other PW JT9D-3A, -7, -7A, -7F, -7H, -7AH, and -7J turbofan engines of the same type design. We are issuing this AD to prevent an engine fire caused by a failed gearbox pressure tube. This AD requires a one-time visual inspection of the gearbox pressure tube, P/N 697896, the No. 4 bearing front pressure manifold, P/N 670663, and the attaching clamp assemblies, P/Ns ST1594-06, ST1594-08, and ST1594-10, for correct positioning, for wear and damage, and replacement if necessary.

FAA's Determination of the Effective Date

Since an unsafe condition exists that requires the immediate adoption of this AD, we have found that notice and opportunity for public comment before issuing this AD are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Changes to 14 CFR Part 39—Effect on the AD

On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 47998, July 22, 2002), which governs our AD system. This regulation now includes material that relates to special flight permits, alternative methods of compliance, and altered products. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include “AD Docket No. 2003-NE-52-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 rule that might suggest a need to modify it. If a person contacts us verbally, and that contact relates to a substantive part of this 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 AD in light of those comments.

We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications with you. You can get more information about plain language at http://www.faa.gov/​language and http://www.plainlanguage.gov.

Examining the AD Docket

You may examine the AD Docket (including any comments and service information), by appointment, between 8:00 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.

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 the 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. 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 by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2003-NE-52-AD” in your request.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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 adding the following new airworthiness directive:

2003-24-12 Pratt & Whitney: Amendment 39-13381. Docket No. 2003-NE-52-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective December 18, 2003.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Pratt & Whitney (PW) JT9D-3A -7, -7A, -7F, -7H, -7AH, and -7J turbofan engines, with gearbox pressure tube, part number (P/N) 697896, and No. 4 bearing front pressure manifold, P/N 670663, installed. These engines are installed on, but not limited to, Boeing 747-100, -200B, -200C, and -200F airplanes.

Unsafe Condition

(d) This AD is prompted by a report of a failed gearbox pressure tube that resulted in an engine fire. We are issuing this AD to prevent engine fires caused by failed gearbox pressure tubes or failed No. 4 bearing front pressure manifolds.

Compliance

(e) You are responsible for having the actions required by this AD performed within 250 hours-in-service or at the next shop visit, whichever occurs first, after the effective date of this AD, unless the actions have already been done.

One-Time Visual Inspection of Clamp Assemblies

(f) Visually inspect the clamp assemblies, P/Ns ST1594-06, ST1594-08, and ST1594-10, that attach the gearbox pressure tube and the No. 4 bearing front pressure manifold to the engine. Replace clamp assemblies before further flight that are rejected by any of the following rejection criteria:

(1) Droop in the No. 4 bearing front pressure manifold.

(2) Cracks, wear, or distortion in clamp metal.

(3) Clamp cushions that are worn, compacted, cracked, coming apart in chunks, deteriorated, or missing. A reddish powder found around the clamp is an indication of deterioration.

One-Time Visual Inspection of Gearbox Pressure Tube and No. 4 Bearing Front Pressure Manifold

(g) Clean any debris and oil from the outer surface of the gearbox pressure tube and No. 4 bearing front pressure manifold and visually inspect the tube and manifold. Repair or replace the affected tube or manifold before further flight if it is rejected by any of the following rejection criteria:

(1) Nicks, chafing, scratches, and or pitting 0.003 inch or greater in depth.

(2) Dents within 0.25 inch of the ferrules or will not permit free passage of a ball having a diameter slightly greater than 80% of the tube or manifold tubing inner diameter.

(3) Corrosion that is unable to be removed by a light polishing.

(4) Tube or manifold is leaking oil.

Gearbox Pressure Tube, No. 4 Bearing Front Pressure Manifold, and Clamp Assembly Positioning

(h) If the gearbox pressure tube, No. 4 bearing front pressure manifold, or clamp assemblies are not properly positioned, then correctly position them before further flight, as shown in the following Figure 1 of this AD.

(i) Information on general inspection of these parts can be found in the Boeing 747 Aircraft Maintenance Manual, section 72-00-00, and in PW Standard Practices Manual, P/N 585005.

Reporting Requirements

(j) Report within 30 calendar days of the inspection, the results that equal or exceed the reject criteria to: Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone [phone]; fax [phone]. Reporting requirements have been approved by the Office of Management and Budget control number 2120-0056.

Alternative Methods of Compliance

(k) 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.

Material Incorporated by Reference

(l) None.

Related Information

(m) None.

Issued in Burlington, Massachusetts, on November 25, 2003.

Jay J. Pardee,

Manager, Engine and Propeller Directorate, Aircraft Certification Service.