AD 2004-04-09

This AD becomes effective April 5, 2004. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of April 5, 2004.

You can get the service information identified in this AD from Pratt & Whitney Canada, 1000 Marie-Victorin, Longueuil, Quebec, Canada J4G1A1, telephone (800) 268-8000; fax (450) 647-2888.

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. You may examine the service information, by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-7178; fax (781) 238-7199.

The FAA proposed to amend 14 CFR Part 39 with a proposed airworthiness directive (AD). The proposed AD applies to PWC JT15D-1, -1A, and -1B turbofan engines with certain impellers part number (P/N) 3020365. We published the proposed AD in the Federal Register on November 13, 2003 (68 FR 64295). That action proposed to require a one-time borescope inspection of the rear face of certain impellers for evidence of a machined groove or step, and repair or replacement of the impeller if a groove or step is found.

We provided the public the opportunity to participate in the development of this AD. We received no comments on the proposal or on the determination of the cost to the public.

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

On July 10, 2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's AD system. That regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. The material previously was included in each individual AD. Since the material is included in 14 CFR part 39, we will not include it in future AD actions.

There are about 1,300 PWC JT15D-1, -1A, and -1B turbofan engines of the affected design in the worldwide fleet. We estimate that 740 of the PWC engines installed on airplanes of U.S. registry are affected by this AD. We also estimate that it will take about 2 work hours per engine to perform the inspection at a hot section inspection interval, and 30 work hours per engine to replace impellers found with a groove or a step in the rear face at shop visit. The average labor rate is $65 per work hour. Required parts will cost about $55,427 per engine. Based on these figures, we estimate that for impellers inspected at hot section inspections, the total labor cost of the AD to U.S. operators is $96,200. On the basis of 100 percent replacement, the total labor cost of the AD to U.S. operators is estimated to be $1,443,000 and the parts replacement cost is estimated to be $41,015,980 for a total replacement cost of $42,555,180.

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 this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866;

(2) Is not a “significant rule” under 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-41-AD” in your request.

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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 (AD):