AD 2003-24-12

This AD becomes effective December 18, 2003.

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

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: (781) 238-7055.

• By e-mail: 9-ane-adcomment@faa.gov.

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.

Keith Lardie, Aerospace Engineer, Aircraft Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park; telephone (781) 238-7189; fax (781) 238-7199.

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.

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.

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.

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.

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.

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.

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.

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:

1. The authority citation for part 39 continues to read as follows:

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.