AD 99-27-16

This amendment adopts a new airworthiness directive (AD), applicable to CFE Company Model CFE738-1-1B turbofan engines. This AD requires, on certain engines identified by serial numbers: a one-time visual inspection of Stage 2 high pressure turbine (HPT) aft cooling plates for nicks, dents, and scratches, and if present, dimensional inspection of indentation depth; repair, if indentation is within acceptable limits, and, if necessary, replacement with serviceable parts. This AD also requires inspection for raised metal on the Stage 2 HPT rotor disk post aft surface that mates with the Stage 2 HPT aft cooling plate, and removal of the raised metal, if present. This amendment is prompted by reports of Stage 2 HPT aft cooling plates that were dented during the assembly of the cooling plate to the Stage 2 disk due to raised metal on the stage 2 HPT disk post aft mating surface. The actions specified by this AD are intended to prevent aft HPT cooling plate failure, which couldresult in an uncontained engine failure and damage to the airplane.

Final rule.

99-27-16 CFE Company: Amendment 39-11497. Docket 99-NE-39-AD. Issued December 29, 1999.
Applicability: CFE Model CFE738-1-1B turbofan engines, serial numbers (S/Ns) 105267 through 105339, inclusive. These engines are installed on but not limited to Dassault-Breguet Falcon 2000 series aircraft.
Note 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, therequest should include specific proposed actions to address it.
Compliance: Required as indicated, unless accomplished previously.
To prevent aft HPT cooling plate failure, which could result in an uncontained engine failure and damage to the airplane, accomplish the following: Inspections and Follow-On Actions
(a) At the next engine shop visit after the effective date of this AD where the HPT assembly is sufficiently disassembled to afford access to the Stage 2 HPT aft cooling plate, but not later than 4500 part cycles-since-new (CSN), accomplish the following in accordance with CFE Alert Service Bulletin (ASB) No. CFE738-A72-8031, Revision 1, dated June 23, 1999, as follows:
(1) Inspect the stage 2 HPT aft cooling plate for nicks, dents, and scratches on surface D in accordance with the requirements of ASB No. CFE738-A72-8031, paragraph 2.B.(1).
(2) Repair those stage 2 HPT aft cooling plates with indentation less than 0.003 inch deep in accordance with ASB No. CFE738-A72-8031. paragraph 2.B.(1).
(3) Remove from service prior to further flight those stage 2 HPT aft cooling plates that have nicks, dents, and/or scratches that exceed the acceptance limits in accordance with ASB No. CFE738-A72-8031 paragraph 2.B.(1), and replace with serviceable parts.
(4) Inspect the stage 2 HPT rotor disk post aft mating surface for raised metal, and remove raised metal if present in accordance with ASB No. CFE738-A72-8031, paragraph 2.B.(2). Alternative Methods of Compliance
(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Engine Certification Office (ECO). Operators shall submit their request through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO.
Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, ifany, may be obtained from the ECO. Ferry Flights
(c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the inspection requirements of this AD can be accomplished. Incorporation by Reference
(d) The actions required by this AD shall be done in accordance with the following CFE ASB:

Document No.
Revision
Pages
Date
CFE738-A72-8031
1
1
June 23, 1999

Original
2-5
May 17, 1999
Total pages: 5.

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from CFE Company, Data Distribution, MS 64-03/2101-201, P.O. , PO Box 29003 Phoenix, AZ 85038-9003; telephone (602) 365-2493, fax (602) 365-5577. Copies may be inspected 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.
(e) This amendment becomes effective on February 10, 2000.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain CFE Company Model CFE738-1-1B turbofan engines was published in the Federal Register on September 28, 1999 (64 FR 52259). That action proposed to require, on certain engines identified by serial numbers: a one-time visual inspection of Stage 2 high pressure turbine (HPT) aft cooling plates for nicks, dents, and scratches, and if present, dimensional inspection of indentation depth; repair, if indentation is within acceptable limits, and, if necessary, replacement with serviceable parts. This Ad also requires inspection for raised metal on the Stage 2 HPT rotor disk post aft surface that mates with the Stage 2 HPT aft cooling plate, and removal of the raised metal, if present. That action was prompted by reports of Stage 2 HPT aft cooling plates that were dented during the assembly of the cooling plate tothe Stage 2 disk due to raised metal on the stage 2 HPT disk post aft mating surface. That condition, if not corrected, could result in aft HPT cooling plate failure, which could result in an uncontained engine failure and damage to the airplane. No Comments Received
Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed. Economic Analysis
There are approximately 72 engines of the affected design in the worldwide fleet. The FAA estimates that 48 engines installed on aircraft of US registry will be affected by this AD, that it will take approximately 4 work hours per engine to accomplish the required inspection if the inspection does not take place during scheduled maintenance, and that the average labor rate is $60 per work hour.Required parts cost approximately $1,536 per engine. Based on these figures, the total cost impact of the AD on US operators is estimated to be $106,560. Regulatory Impact
The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order (EO) 13132.
For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under EO 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 thisaction and it 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. List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
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: 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. Section 39.13 is amended by adding the following new airworthiness directive: