AD 2000-13-01

Effective date September 1, 2000. The incorporation by reference of certain publications listed in the rule is approved by the Director of the Federal Register as of September 1, 2000.

The service information referenced in this AD may be obtained from Rolls-Royce Allison, P.O. Box 420, Indianapolis, IN 46206-0420; telephone: (888) 255-4766. This information may be examined at the Federal Aviation Administration (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.

John Tallarovic, Aerospace Engineer, Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 2300 East Devon Avenue, Des Plaines, IL 60018; telephone (847) 294-8180, fax (847) 294-7834.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) applicable to Allison Engine Company, Inc. AE 3007A and AE 3007C series turbofan engines was published in the Federal Register on August 5, 1999 (64 FR 42622). That action proposed to require the removal of certain turbine wheels from service before exceeding new, reduced cyclic life limits listed in Rolls-Royce Alert Service Bulletin (ASB) AE 3007A-A-72-105/AE 3007C-A-72-105, dated January 29, 1999.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

One commenter supports the proposed rule as written.

One commenter requests the addition of part numbers (P/N) to the compliance section. The commenter states that the way the NPRM is written, paragraphs (a)(2) and (b)(2) could be interpreted to mean that all stage 1 and stage 2 turbine wheels, respectively, should have lower lives. In fact, the life reduction is limited to a few part numbers. The addition of the affected part numbers would prevent confusion.

The FAA agrees. To eliminate confusion, paragraph (a)(2) of the compliance section of the final rule has been revised to specify P/Ns 23065891 and 23062373. Paragraph (b)(2) of the compliance section of the final rule has been revised to specify P/Ns 23065892 and 23063462.

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes described previously. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

There are approximately 325 engines of the affected design in the worldwide fleet. The FAA estimates that 260 engines installed on aircraft of U.S. registry will be affected by this AD, that it will take approximately 63 work hours per engine to accomplish the required actions, and that the average labor rate is $60 per work hour. The estimated cost of the lost cycles due to the reduction of the engine cycle life limit is $57,800 per engine. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $15,028,000. The manufacturer of the affected turbine wheels has advised the FAA that it may defray the cost of the reduced life limits, thus reducing the overall cost to operators.

This rule does not have federalism implications, as defined in Executive Order 13132, because it does 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. Accordingly, the FAA has not consulted with state authorities prior to publication of this rule.

For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action and is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

Accordingly, pursuant to 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. Section 39.13 is amended by adding the following new airworthiness directive: